The Inside Story to Indoor Air Quality
The Inside Story to Indoor Air
Quality
Air Pollution Sources in the Home
Introduction
Indoor Air Quality in Your Home
What If You Live in an Apartment?
Improving the Air Quality in Your Home
A Look at Source-Specific Controls
Radon
Environmental Tobacco Smoke
Biological Contaminants
Stoves, Heaters, Fireplaces, and Chimneys
Household Products
Formaldehyde
Pesticides
Asbestos
Lead
Reference Guide to Major Indoor Air Pollutants
in the Home
When Building a New Home
Do You Suspect Your Office Has an Indoor Air Problem?
Where to Go for Additional Information
Glossary
AIR POLLUTION SOURCES IN THE HOME
1. Moisture
2. Pressed Wood Furniture
3. Humidifier
4. Moth Repellents
5. Dry-Cleaned Goods
6. House Dust Mites
7. Personal Care Products
8. Air Freshener
9. Stored Fuels
10. Car Exhaust
11. Paint Supplies
12. Paneling
13. Wood Stove
14. Tobacco Smoke
15. Carpets
16. Pressed Wood Sub flooring
17. Drapes
18. Fireplace
19. Household Chemicals
20. Asbestos Floor Tiles
21. Pressed Wood Cabinets
22. Unvented Gas Stove
23. Asbestos Pipe Wrap
24. Radon
25. Unvented Clothes Dryer
26. Pesticides
27. Stored Hobby Products
28. Lead-Based Paint
INDOOR AIR QUALITY CONCERNS
All of us face a variety of risks to our
health as we go
about our day to day lives. Driving in cars,
flying in planes,
engaging in recreational activities, and being
exposed to
environmental pollutants all pose varying degrees
of risk. Some
risks are simply unavoidable. Some we choose to
accept because to
do otherwise would restrict our ability to lead
our lives the way
we want. And some are risks we might decide to
avoid if we had
the opportunity to make informed choices. Indoor
air pollution
is one risk that you can do something about.
In the last several years, a growing body
of scientific
evidence has indicated that the air within homes
and other
buildings can be more seriously polluted than
the outdoor air in
even the largest and most industrialized cities.
Other research
indicates that people spend approximately 90 percent
of their
time indoors. Thus, for many people, the risks
to health may be
greater due to exposure to air pollution indoors
than outdoors.
In addition, people who may be exposed to
indoor air
pollutants for the longest periods of time are
often those most
susceptible to the effects of indoor air pollution.
Such groups
include the young, the elderly, and the chronically
ill,
especially those suffering from respiratory or
cardiovascular
disease.
WHY A BOOKLET ON INDOOR AIR?
While pollutant levels from individual
sources may not pose
a significant health risk by themselves, most
homes have more
than one source that contributes to indoor air
pollution. There
can be a serious risk from the cumulative effects
of these
sources. Fortunately, there are steps that most
people can take
both to reduce the risk from existing sources
and to prevent new
problems from occurring. This booklet was prepared
by the U.S.
Environmental Protection Agency (EPA) and the
U.S. Consumer
Product Safety Commission (CPSC) to help you decide
whether to
take actions that can reduce the level of indoor
air pollution in
your own home.
Because so many Americans spend a lot of
time in offices
with mechanical heating, cooling, and ventilation
systems, there
is also a short section on the causes of poor
air quality in
offices and what you can do if you suspect that
your office may
have a problem. A glossary and a list of organizations
where you
can get additional information are listed at the
back of this
booklet.
WHAT CAUSES INDOOR AIR PROBLEMS?
Indoor pollution sources that release
gases or particles
into the air are the primary cause of indoor air
quality problems
in homes. Inadequate ventilation can increase
indoor pollutant
levels by not bringing in enough outdoor air to
dilute emissions
from indoor sources and by not carrying indoor
air pollutants out
of the home. High temperature and humidity levels
can also
increase concentrations of some pollutants.
Pollutant Sources
There are many sources of indoor air pollution
in any home.
These include combustion sources such as oil,
gas, kerosene,
coal, wood, and tobacco products; building materials
and
furnishings as diverse as deteriorated, asbestos
containing
insulation, wet or damp carpet, and cabinetry
or furniture made
of certain pressed wood products; products for
household cleaning
and maintenance, personal care, or hobbies; central
heating and
cooling systems and humidification devices; and
outdoor sources
such as radon, pesticides, and outdoor air pollution.
The relative importance of any single source
depends on how
much of a given pollutant it emits and how hazardous
those
emissions are. In some cases, factors such as
how old the source
is and whether it is properly maintained are significant.
For
example, an improperly adjusted gas stove can
emit significantly
more carbon monoxide than one that is properly
adjusted.
Some sources, such as building materials,
furnishings, and
household products like air fresheners, release
pollutants more
or less continuously. Other sources, related to
activities
carried out in the home, release pollutants intermittently.
These
include smoking, the use of unvented or malfunctioning
stoves,
furnaces, or space heaters, the use of solvents
in cleaning and
hobby activities, the use of paint strippers in
redecorating
activities, and the use of cleaning products and
pesticides in
housekeeping. High pollutant concentrations can
remain in the air
for long periods after some of these activities.
Amount of Ventilation
If too little outdoor air enters a home,
pollutants can
accumulate o levels that can pose health and comfort
problems.
Unless they are built with special mechanical
means of
ventilation, homes that are designed and constructed
to minimize
the amount of outdoor air that can leak into and
out of the home
may have higher pollutant levels than other homes.
However,
because some weather conditions can drastically
reduce the amount
of outdoor air that enters a home, pollutants
can build up even
in homes that are normally considered leaky.
HOW DOES OUTDOOR AIR ENTER A HOUSE?
Outdoor air enters and leaves a house by:
infiltration,
natural ventilation, and mechanical ventilation.
In a process
known as infiltration, outdoor air flows into
the house through
openings, joints, and cracks in walls, floors,
and ceilings, and
around windows and doors. In natural ventilation,
air moves
through opened windows and doors. Air movement
associated with
infiltration and natural ventilation is caused
by air temperature
differences between indoors and outdoors and by
wind. Finally,
there are a number of mechanical ventilation devices,
from
outdoor vented fans that intermittently remove
air from a single
room, such as bathrooms and kitchen, to air handling
systems that
use fans and duct work to continuously remove
indoor air and
distribute filtered and conditioned outdoor air
to strategic
points throughout the house. The rate at which
outdoor air
replaces indoor air is described as the air exchange
rate. When
there is little infiltration, natural ventilation,
or mechanical
ventilation, the air exchange rate is low and
pollutant levels
can increase.
WHAT IF YOU LIVE IN AN APARTMENT?
Apartments can have the same indoor air problems
as single family
homes because many of the pollution sources, such
as the interior
building materials, furnishings, and household
products, are
similar. Indoor air problems similar to those
in offices are
caused by such sources as contaminated ventilation
systems,
improperly placed outdoor air intakes, or maintenance
activities.
Solutions to air quality problems in apartments,
as in homes and
offices, involve such actions as: eliminating
or controlling the
sources of pollution, increasing ventilation,
and installing air
cleaning devices. Often a resident can take the
appropriate
action to improve the indoor air quality by removing
a source,
altering an activity, unblocking an air supply
vent, or opening a
window to temporarily increase the ventilation;
in other cases,
however, only the building owner or manager is
in a position to
remedy the problem. (See the section What to
Do If You Suspect
a Problem on page 30.) You can encourage building
management to
follow guidance in EPA and NIOSH s Building Air
Quality: A Guide
for Building Owners and Facility Managers. It
is available for
$24 from the Superintendent of Documents, P.O.
Box 371954,
Pittsburgh, PA 152507954; stock # 055000003904.
INDOOR AIR AND YOUR HEALTH
Health effects from indoor air pollutants may
be experienced soon
after exposure or, possibly, years later.
Immediate effects may show up after a single
exposure or repeated
exposures. These include irritation of the eyes,
nose, and
throat, headaches, dizziness, and fatigue. Such
immediate effects
are usually short term and treatable. Sometimes
the treatment is
simply eliminating the person s exposure to the
source of the
pollution, if it can be identified. Symptoms of
some diseases,
including asthma, hypersensitivity pneumonitis,
and humidifier
fever, may also show up soon after exposure to
some indoor air
pollutants.
The likelihood of immediate reactions to indoor
air pollutants
depends on several factors. Age and preexisting
medical
conditions are two important influences. In other
cases, whether
a person reacts to a pollutant depends on individual
sensitivity,
which varies tremendously from person to person.
Some people can
become sensitized to biological pollutants after
repeated
exposures, and it appears that some people can
become sensitized
to chemical pollutants as well.
Certain immediate effects are similar
to those from colds or
other viral diseases, so it is often difficult
to determine if
the symptoms are a result of exposure to indoor
air pollution.
For this reason, it is important to pay attention
to the time and
place the symptoms occur. If the symptoms fade
or go away when a
person is away from the home and return when the
person returns,
an effort should be made to identify indoor air
sources that may
be possible causes. Some effects may be made worse
by an
inadequate supply of outdoor air or from the heating,
cooling, or
humidity conditions prevalent in the home.
Other health effects may show up either years
after exposure has
occurred or only after long or repeated periods
of exposure.
These effects, which include some respiratory
diseases, heart
disease, and cancer, can be severely debilitating
or fatal. It is
prudent to try to improve the indoor air quality
in your home
even if symptoms are not noticeable. More information
on
potential health effects from particular indoor
air pollutants is
provided in the section, A Look at Source Specific
Controls.
While pollutants commonly found in indoor air
are responsible for
many harmful effects, there is considerable uncertainty
about
what concentrations or periods of exposure are
necessary to
produce specific health problems. People also
react very
differently to exposure to indoor air pollutants.
Further
research is needed to better understand which
health effects
occur after exposure to the average pollutant
concentrations
found in homes and which occur from the higher
concentrations
that occur for short periods of time.
The health effects associated with some indoor
air pollutants are
summarized in the chart in the middle of this
booklet titled
Reference Guide to Major Indoor Air Pollutants
in the Home.
IDENTIFYING AIR QUALITY PROBLEMS
Some health effects can be useful indicators
of an indoor air
quality problem, especially if they appear after
a person moves
to a new residence, remodels or refurnishes a
home, or treats a
home with pesticides. If you think that you have
symptoms that
may be related to your home environment, discuss
the with your
doctor or your local health department to see
if they could be
caused by indoor air pollution. You may also want
to consult a
board certified allergist or an occupational medicine
specialist
for answers to your questions.
Another way to judge whether your home
has or could develop
indoor air problems is to identify potential sources
of indoor
air pollution. Although the presence of such sources
(see
illustration at the beginning of this booklet)
does not
necessarily mean that you have an indoor air quality
problem,
being aware of the type and number of potential
sources is an
important step toward assessing the air quality
in your home.
A third way to decide whether your home may
have poor indoor air
quality is to look at your lifestyle and activities.
Human
activities can be significant sources of indoor
air pollution.
Finally, look for signs of problems with the ventilation
in your
home. Signs that can indicate your home may not
have enough
ventilation include moisture condensation on windows
or walls,
smelly or stuffy air, dirty central heating and
air cooling
equipment, and areas where books, shoes, or other
items become
moldy. To detect odors in your home, step outside
for a few
minutes, and then upon reentering your home, note
whether odors
are noticeable.
MEASURING POLLUTANT LEVELS
The federal government recommends that you
measure the level of
radon in your home. Without measurements there
is no way to tell
whether radon is present because it is a colorless,
odorless,
radioactive gas. Inexpensive devices are available
for measuring
radon. EPA provides guidance as to risks associated
with
different levels of exposure and when the public
should consider
corrective action. There are specific mitigation
techniques that
have proven effective in reducing levels of radon
in the home.
(See Radon section on p. 11 of this booklet
for additional
information about testing and controlling radon
in homes.)
For pollutants other than radon, measurements
are most
appropriate when there are either health symptoms
or signs of
poor ventilation and specific sources or pollutants
have been
identified as possible causes of indoor air quality
problems.
Testing for many pollutants can be expensive.
Before monitoring
your home for pollutants besides radon, consult
your state or
local health department or professionals who have
experience in
solving indoor air quality problems in nonindustrial
buildings.
WEATHERIZING YOUR HOME
The federal government recommends that homes
be weatherized in
order to reduce the amount of energy needed for
heating and
cooling. While weatherization is underway, however,
steps should
also be taken to minimize pollution from sources
inside the home.
(See Improving the Air Quality in Your Home
for recommended
actions.) In addition, residents should be alert
to the emergence
of signs of inadequate ventilation, such as stuffy
air, moisture
condensation on cold surfaces, or mold and mildew
growth.
Additional weatherization measures should not
be undertaken until
these problems have been corrected.
Weatherization generally does not cause indoor
air problems by
adding new pollutants to the air. (There are a
few exceptions,
such as caulking, that can sometimes emit pollutants.)
However,
measures such as installing storm windows, weather
stripping,
caulking, and blown in wall insulation can reduce
the amount of
outdoor air infiltrating into a home. Consequently,
after
weatherization, concentrations of indoor air pollutants
from
sources inside the home can increase.
THREE BASIC STRATEGIES
Source Control
Usually the most effective way to improve indoor
air quality is
to eliminate individual sources of pollution or
to reduce their
emissions. Some sources, like those that contain
asbestos, can be
sealed or enclosed; others, like gas stoves, can
be adjusted to
decrease the amount of emissions. In many cases,
source control
is also a more cost efficient approach to protecting
indoor air
quality than increasing ventilation because increasing
ventilation can increase energy costs. Specific
sources of indoor
air pollution in your home are listed later in
this section.
Ventilation Improvements
Another approach to lowering the concentrations
of indoor air
pollutants in your home is to increase the amount
of outdoor air
coming indoors. Most home heating and cooling
systems, including
forced air heating systems, do not mechanically
bring fresh air
into the house. Opening windows and doors, operating
window or
attic fans, when the weather permits, or running
a window air
conditioner with the vent control open increases
the outdoor
ventilation rate. Local bathroom or kitchen fans
that exhaust
outdoors remove contaminants directly from the
room where the fan
is located and also increase the outdoor air ventilation
rate.
It is particularly important to take as
many of these steps
as possible while you are involved in short-term
activities that
can generate high levels of pollutants for example,
painting,
paint stripping, heating with kerosene heaters,
cooking, or
engaging in maintenance and hobby activities such
as welding,
soldering, or sanding. You might also choose to
do some of these
activities outdoors, if you can and if weather
permits.
Advanced designs of new homes are starting
to feature mechanical
systems that bring outdoor air into the home.
Some of these
designs include energy efficient heat recovery
ventilators (also
known as air-to-air heat exchangers). For more
information about
air-to-air heat exchangers, contact the Conservation
and
Renewable Energy Inquiry and Referral Service
(CAREIRS), PO Box
3048, Merrifield, VA 22116; (800) 5232929.
Air Cleaners
There are many types and sizes of air cleaners
on the market,
ranging from relatively inexpensive tabletop models
to
sophisticated and expensive whole house systems.
Some air
cleaners are highly effective at particle removal,
while others,
including most tabletop models, are much less
so. Air cleaners
are generally not designed to remove gaseous pollutants.
The effectiveness of an air cleaner depends
on how well it
collects pollutants from indoor air (expressed
as a percentage
efficiency rate) and how much air it draws through
the cleaning
or filtering element (expressed in cubic feet
per minute). A very
efficient collector with a low air circulation
rate will not be
effective, nor will a cleaner with a high air
circulation rate
but a less efficient collector. The long term
performance of any
air cleaner depends on maintaining it according
to the
manufacturer s directions.
Another important factor in determining
the effectiveness of
an air cleaner is the strength of the pollutant
source. Tabletop
air cleaners, in particular, may not remove satisfactory
amounts
of pollutants from strong nearby sources. People
with a
sensitivity to particular sources may find that
air cleaners are
helpful only in conjunction with concerted efforts
to remove the
source.
Over the past few years, there has been
some publicity
suggesting that house plants have been shown to
reduce levels of
some chemicals in laboratory experiments. There
is currently no
evidence, however, that a reasonable number of
houseplants remove
significant quantities of pollutants in homes
and offices.
Indoor houseplants should not be over watered
because overly damp
soil may promote the growth of microorganisms
which can affect
allergic individuals.
At present, EPA does not recommend using
air cleaners to
reduce levels of radon and its decay products.
The effectiveness
of these devices is uncertain because they only
partially remove
the radon decay products and do not diminish the
amount of radon
entering the home. EPA plans to do additional
research on whether
air cleaners are, or could become, a reliable
means of reducing
the health risk from radon. EPA s booklet, Residential
Air
Cleaning Devices, provides further information
on air cleaning
devices to reduce indoor air pollutants
For most indoor air quality problems in the
home, source control
is the most effective solution. This section takes
a source by
source look at the most common indoor air pollutants,
their
potential health effects, and ways to reduce levels
in the home.
(For a summary of the points made in this section,
see the chart
in the middle of this booklet titled Reference
Guide to Major
Indoor Air Pollutants in the Home. )
RADON
The most common source of indoor radon is uranium
in the soil or
rock on which homes are built. As uranium naturally
breaks down,
it releases radon gas which is a colorless, odorless,
radioactive
gas. Radon gas enters homes through dirt floors,
cracks in
concrete walls and floors, floor drains, and sumps.
When radon
become strapped in buildings and concentrations
build up indoors,
exposure to radon becomes a concern.
Any home may have a radon problem. This
means new and old
homes, well sealed and drafty homes, and homes
with or without
basements.
Sometimes radon enters the home through well
water. In a small
number of homes, the building materials can give
off radon, too.
However, building materials rarely cause radon
problems by
themselves.
Health Effects of Radon
The predominant health effect associated with
exposure to
elevated levels of radon is lung cancer. Research
suggests that
swallowing water with high radon levels may pose
risks, too,
although these are believed to be much lower than
those from
breathing air containing radon. Major health organizations
(like
the Centers for Disease Control and Prevention,
the American Lung
Association (ALA), and the American Medical Association)
agree
with estimates that radon causes thousands of
preventable lung
cancer deaths each year. EPA estimates that radon
causes about
14,000 deaths per year in the United States however,
this number
could range from 7,000 to 30,000 deaths per year.
If you smoke
and your home has high radon levels, your risk
of lung cancer is
especially high.
Reducing Exposure to Radon in Homes
Measure levels of radon in your home.
You can t see radon, but it s not hard to find
out if you have a
radon problem in your home. Testing is easy and
should only take
a little of your time.
There are many kinds of inexpensive, do-it-yourself
radon
test kits you can get through the mail and in
hardware stores and
other retail outlets. Make sure you buy a test
kit that has
passed EPA s testing program or is state certified.
These kits
will usually display the phrase Meets EPA Requirements.
If you
prefer, or if you are buying or selling a home,
you can hire a
trained contractor to do the testing for you.
The EPA Radon
Measurement Proficiency (RMP) Program evaluates
testing
contractors. A contractor who has met EPA s requirements
will
carry a special RMP identification card. EPA
provides a list of
companies and individual contractors to state
radon offices. You
can call your state radon office to obtain a list
of qualified
contractors in your area (call 800-SOS-RADON for
a list of state
radon offices).
Refer to the EPA guidelines on how to test
and interpret your
test results.
You can learn more about radon through EPA
s publications, A
Citizen s Guide to Radon: The Guide to Protecting
Yourself and
Your Family From Radon and Home Buyer s and Seller
s Guide to
Radon, which are available from state radon offices.
Learn about radon reduction methods.
Ways to reduce radon in your home are discussed
in EPA s Consumer
s Guide to Radon Reduction. You can get a copy
from your state
radon office. There are simple solutions to radon
problems in
homes. Thousands of homeowners have already fixed
radon
problems. Lowering high radon levels requires
technical
knowledge and special skills. You should use
a contractor who is
trained to fix radon problems.
The EPA Radon Contractor Proficiency (RCP)
Program tests
these contractors. EPA provides a list of RCP
contractors to
state radon offices. A contractor who is listed
by EPA will
carry a special RCP identification card. A trained
RCP
contractor can study the problem in your home
and help you pick
the correct treatment method. Check with your
state radon office
for names of qualified or state certified radon
reduction
contractors in your area.
Stop smoking and discourage smoking in your
home.
Scientific evidence indicates that smoking
combined with radon is
an especially serious health risk. Stop smoking
and lower your
radon level to reduce lung cancer risk.
Treat radon contaminated well water.
While radon in water is not a problem in homes
served by most
public water supplies, it has been found in well
water. If
you've tested the air in your home and found a
radon problem, and
you have a well, contact a lab certified to measure
radiation in
water to have your water tested. Radon problems
in water can be
readily fixed. Call your state radon office or
the EPA Drinking
Water Hotline (8004264791) for more information.
ENVIRONMENTAL TOBACCO SMOKE
Environmental tobacco smoke (ETS) is the mixture
of smoke that
comes from the burning end of a cigarette, pipe,
or cigar, and
smoke exhaled by the smoker. It is a complex mixture
of over
4,000 compounds, more than 40 of which are known
to cause cancer
in humans or animals and many of which are strong
irritants.
ETS is often referred to as secondhand smoke
and exposure to
ETS is often called passive smoking.
Health Effects of Environmental Tobacco Smoke
In 1992, EPA completed a major assessment of
the respiratory
health risks of ETS (Respiratory Health Effects
of Passive
Smoking: Lung Cancer and Other Disorders EPA/600/690/006F).
The
report concludes that exposure to ETS is responsible
for
approximately 3,000 lung cancer deaths each year
in non-smoking
adults and impairs the respiratory health of hundreds
of
thousands of children.
Infants and young children whose parents
smoke in their
presence are at increased risk of lower respiratory
tract
infections (pneumonia and bronchitis) and are
more likely to have
symptoms of respiratory irritation like cough,
excess phlegm, and
wheeze. EPA estimates that passive smoking annually
causes
between 150,000 and 300,000 lower respiratory
tract infections in
infants and children under 18 months of age, resulting
in between
7,500 and 15,000 hospitalizations each year.
These children may
also have a buildup of fluid in the middle ear,
which can lead to
ear infections. Older children who have been
exposed to
secondhand smoke may have slightly reduced lung
function.
Asthmatic children are especially at risk.
EPA estimates that
exposure to secondhand smoke increases the number
of episodes and
severity of symptoms in hundreds of thousands
of asthmatic
children, and may cause thousands of non-asthmatic
children to
develop the disease each year. EPA estimates
that between
200,000 and 1,000,000 asthmatic children have
their condition
made worse by exposure to secondhand smoke each
year.
Exposure to secondhand smoke causes eye, nose,
and throat
irritation. It may affect the cardiovascular
system and some
studies have linked exposure to secondhand smoke
with the onset
of chest pain. For publications about ETS, contact
EPA s Indoor
Air Quality Information Clearinghouse (IAQ-INFO),
8004384318.
Reducing Exposure to Environmental Tobacco
Smoke
Don t smoke at home or permit others to do
so. Ask smokers to
smoke outdoors.
The 1986 Surgeon General s report concluded
that physical
separation of smokers and nonsmokers in a common
air space, such
as different rooms within the same house, may
reduce but will not
eliminate nonsmokers exposure to environmental
tobacco smoke.
If smoking indoors cannot be avoided, increase
ventilation in
the area where smoking takes place.
Open windows or use exhaust fans. Ventilation,
a common method
of reducing exposure to indoor air pollutants,
also will reduce
but not eliminate exposure to environmental tobacco
smoke.
Because smoking produces such large amounts of
pollutants,
natural or mechanical ventilation techniques do
not remove them
from the air in your home as quickly as they build
up. In
addition, the large increases in ventilation it
takes to
significantly reduce exposure to environmental
tobacco smoke can
also increase energy costs substantially. Consequently,
the most
effective way to reduce exposure to environmental
tobacco smoke
in the home is to eliminate smoking there.
Do not smoke if children are present, particularly
infants and
toddlers.
Children are particularly susceptible to the
effects of passive
smoking. Do not allow baby sitters or others
who work in your
home to smoke indoors. Discourage others from
smoking around
children. Find out about the smoking policies
of the day care
center providers, schools, and other care givers
for your
children. The policy should protect children
from exposure to
ETS.
BIOLOGICAL CONTAMINANTS
Biological contaminants include bacteria, molds,
mildew, viruses,
animal dander and cat saliva, house dust mites,
cockroaches, and
pollen. There are many sources of these pollutants.
Pollens
originate from plants; viruses are transmitted
by people and
animals; bacteria are carried by people, animals,
and soil and
plant debris; and household pets are sources of
saliva and animal
dander. The protein in urine from rats and mice
is a potent
allergen. When it dries, it can become airborne.
Contaminated
central air handling systems can become breeding
grounds for
mold, mildew, and other sources of biological
contaminants and
can then distribute these contaminants through
the home.
By controlling the relative humidity level
in a home, the
growth of some sources of biologicals can be minimized.
A
relative humidity of 3050 percent is generally
recommended for
homes. Standing water, water-damaged materials,
or wet surfaces
also serve as a breeding ground for molds, mildews,
bacteria, and
insects. House dust mites, the source of one of
the most powerful
biological allergens, grow in damp, warm environments.
Health Effects From Biological Contaminants
Some biological contaminants trigger allergic
reactions,
including hypersensitivity pneumonitis, allergic
rhinitis, and
some types of asthma. Infectious illnesses, such
as influenza,
measles, and chicken pox are transmitted through
the air. Molds
and mildews release disease causing toxins. Symptoms
of health
problems caused by biological pollutants include
sneezing, watery
eyes, coughing, shortness of breath, dizziness,
lethargy, fever,
and digestive problems.
Allergic reactions occur only after repeated
exposure to a
specific biological allergen. However, that reaction
may occur
immediately upon re-exposure or after multiple
exposures over
time. As a result, people who have noticed only
mild allergic
reactions, or no reactions at all, may suddenly
find themselves
very sensitive to particular allergens.
Some diseases, like humidifier fever, are associated
with
exposure to toxins from microorganisms that can
grow in large
building ventilation systems. However, these diseases
can also be
traced to microorganisms that grow in home heating
and cooling
systems and humidifiers. Children, elderly people,
and people
with breathing problems, allergies, and lung diseases
are
particularly susceptible to disease causing biological
agents in
the indoor air.
Reducing Exposure to Biological Contaminants
Install and use exhaust fans that are vented
to the outdoors in
kitchens and bathrooms and vent clothes dryers
outdoors.
These actions can eliminate much of the moisture
that builds up
from everyday activities. There are exhaust fans
on the market
that produce little noise, an important consideration
for some
people. Another benefit to using kitchen and
bathroom exhaust
fans is that they can reduce levels of organic
pollutants that
vaporize from hot water used in showers and dishwashers.
Ventilate the attic and crawl spaces to prevent
moisture
buildup.
Keeping humidity levels in these areas below
50 percent can
prevent water condensation on building materials.
If using cool mist or ultrasonic humidifiers,
clean appliances
according to manufacturer s instructions and refill
with fresh
water daily.
Because these humidifiers can become breeding
grounds for
biological contaminants, they have the potential
for causing
diseases such as hypersensitivity pneumonitis
and humidifier
fever. Evaporation trays in air conditioners,
dehumidifiers, and
refrigerators should also be cleaned frequently.
Thoroughly clean and dry water-damaged carpets
and building
materials (within 24 hours if possible) or consider
removal and
replacement.
Water-damaged carpets and building materials
can harbor mold and
bacteria. It is very difficult to completely rid
such materials
of biological contaminants.
Keep the house clean. House dust mites, pollens,
animal dander,
and other allergy causing agents can be reduced,
although not
eliminated, through regular cleaning.
People who are allergic to these pollutants
should use allergen
proof mattress encasements, wash bedding in hot
(130 F) water,
and avoid room furnishings that accumulate dust,
especially if
they cannot be washed in hot water. Allergic individuals
should
also leave the house while it is being vacuumed
because vacuuming
can actually increase airborne levels of mite
allergens and other
biological contaminants. Using central vacuum
systems that are
vented to the outdoors or vacuums with high efficiency
filters
may also be of help.
Take steps to minimize biological pollutants
in basements.
Clean and disinfect the basement floor drain
regularly. Do not
finish a basement below ground level unless all
water leaks are
patched and outdoor ventilation and adequate heat
to prevent
condensation are provided. Operate a dehumidifier
in the basement
if needed to keep relative humidity levels between
30 50 percent.
To learn more about biological pollutants,
read Biological
Pollutants in Your Home issued by the U.S. Consumer
Product
Safety Commission and the American Lung Association.
For contact
information, see the section, Where to Go For
Additional
Information.
STOVES, HEATERS, FIREPLACES, AND CHIMNEYS
In addition to environmental tobacco smoke,
other sources of
combustion products are unvented kerosene and
gas space heaters,
wood stoves, fireplaces, and gas stoves. The major
pollutants
released are carbon monoxide, nitrogen dioxide,
and particles.
Unvented kerosene heaters may also generate acid
aerosols.
Combustion gases and particles also come
from chimneys and
flues that are improperly installed or maintained
and cracked
furnace heat exchangers. Pollutants from fireplaces
and wood
stoves with no dedicated outdoor air supply can
be back drafted
from the chimney into the living space, particularly
in
weatherized homes.
Health Effects of Combustion Products
Carbon monoxide is a colorless, odorless gas
that interferes with
the delivery of oxygen throughout the body. At
high
concentrations it can cause unconsciousness and
death. Lower
concentrations can cause a range of symptoms from
headaches,
dizziness, weakness, nausea, confusion, and disorientation,
to
fatigue in healthy people and episodes of increased
chest pain in
people with chronic heart disease. The symptoms
of carbon
monoxide poisoning are sometimes confused with
the flu or food
poisoning. Fetuses, infants, elderly people,
and people with
anemia or with a history of heart or respiratory
disease can be
especially sensitive to carbon monoxide exposures.
Nitrogen dioxide is a colorless, odorless
gas that irritates
the mucous membranes in the eye, nose, and throat
and causes
shortness of breath after exposure to high concentrations.
There
is evidence that high concentrations or continued
exposure to low
levels of nitrogen dioxide increases the risk
of respiratory
infection; there is also evidence from animal
studies that
repeated exposures to elevated nitrogen dioxide
levels may lead,
or contribute, to the development of lung disease
such as
emphysema. People at particular risk from exposure
to nitrogen
dioxide include children and individuals with
asthma and other
respiratory diseases.
Particles, released when fuels are incompletely
burned, can lodge
in the lungs and irritate or damage lung tissue.
A number of
pollutants, including radon and benzo(a)pyrene,
both of which can
cause cancer, attach to small particles that are
inhaled and then
carried deep into the lung.
Reducing Exposure to Combustion Products in
Homes
Take special precautions when operating fuel
burning unvented
space heaters.
Consider potential effects of indoor air pollution
if you use an
unvented kerosene or gas space heater. Follow
the manufacturer s
directions, especially instructions on the proper
fuel and
keeping the heater properly adjusted. A persistent
yellow tipped
flame is generally an indicator of maladjustment
and increased
pollutant emissions. While a space heater is in
use, open a door
from the room where the heater is located to the
rest of the
house and open a window slightly.
Install and use exhaust fans over gas cooking
stoves and ranges
and keep the burners properly adjusted.
Using a stove hood with a fan vented to
the outdoors greatly
reduces exposure to pollutants during cooking.
Improper
adjustment, often indicated by a persistent yellow
tipped flame,
causes increased pollutant emissions. Ask your
gas company to
adjust the burner so that the flame tip is blue.
If you purchase
a new gas stove or range, consider buying one
with pilotless
ignition because it does not have a pilot light
that burns
continuously. Never use a gas stove to heat your
home. Always
make certain the flue in your gas fireplace is
open when the
fireplace is in use.
Keep wood stove emissions to a minimum. Choose
properly sized
new stoves that are certified as meeting EPA emission
standards.
Make certain that doors in old wood stoves
are tight fitting. Use
aged or cured (dried) wood only and follow the
manufacturer s
directions for starting, stoking, and putting
out the fire in
wood stoves. Chemicals are used to pressure treat
wood; such wood
should never be burned indoors. (Because some
old gaskets in wood
stove doors contain asbestos, when replacing gaskets
refer to the
instructions in the CPSC, ALA, and EPA booklet,
Asbestos in Your
Home, to avoid creating an asbestos problem. New
gaskets are made
of fiberglass.)
Have central air handling systems, including
furnaces, flues,
and chimneys, inspected annually and promptly
repair cracks or
damaged parts.
Blocked, leaking, or damaged chimneys or flues
release harmful
combustion gases and particles and even fatal
concentrations of
carbon monoxide. Strictly follow all service and
maintenance
procedures recommended by the manufacturer, including
those that
tell you how frequently to change the filter.
If manufacturer s
instructions are not readily available, change
filters once every
month or two during periods of use. Proper maintenance
is
important even for new furnaces because they can
also corrode and
leak combustion gases, including carbon monoxide.
Read the
booklet What You Should Know About Combustion
Appliances and
Indoor Air Pollution to learn more about combustion
pollutants.
The booklet is available by contacting CPSC, EPA
s IAQ INFO
Clearinghouse, or your local ALA. (See Where
to Go for
Additional Information for contact information.)
HOUSEHOLD PRODUCTS
Organic chemicals are widely used as ingredients
in household
products. Paints, varnishes, and wax all contain
organic
solvents, as do many cleaning, disinfecting, cosmetic,
decreasing, and hobby products. Fuels are made
up of organic
chemicals. All of these products can release organic
compounds
while you are using them, and, to some degree,
when they are
stored.
EPA s Total Exposure Assessment Methodology
(TEAM) studies
found levels of about a dozen common organic pollutants
to be 2
to 5 times higher inside homes than outside, regardless
of
whether the homes were located in rural or highly
industrial
areas. Additional TEAM studies indicate that while
people are
using products containing organic chemicals, they
can expose
themselves and others to very high pollutant levels,
and elevated
concentrations can persist in the air long after
the activity is
completed.
Health Effects of Household Chemicals
The ability of organic chemicals to cause health
effects varies
greatly from those that are highly toxic, to
those with no
known health effect. As with other pollutants,
the extent and
nature of the health effect will depend on many
factors including
level of exposure and length of time exposed.
Eye and
respiratory tract irritation, headaches, dizziness,
visual
disorders, and memory impairment are among the
immediate symptoms
that some people have experienced soon after exposure
to some
organics. At present, not much is known about
what health effects
occur from the levels of organics usually found
in homes. Many
organic compounds are known to cause cancer in
animals; some are
suspected of causing, or are known to cause, cancer
in humans.
Reducing Exposure to Household Chemicals
Follow label instructions carefully.
Potentially hazardous products often have warnings
aimed at
reducing exposure of the user. For example, if
a label says to
use the product in a well ventilated area, go
outdoors or in
areas equipped with an exhaust fan to use it.
Otherwise, open up
windows to provide the maximum amount of outdoor
air possible.
Throw away partially full containers of old
or unneeded
chemicals safely.
Because gases can leak even from closed containers,
this single
step could help lower concentrations of organic
chemicals in your
home. (Be sure that materials you decide to keep
are stored not
only in a well ventilated area but are also safely
out of reach
of children.) Do not simply toss these unwanted
products in the
garbage can. Find out if your local government
or any
organization in your community sponsors special
days for the
collection of toxic household wastes. If such
days are available,
use them to dispose of the unwanted containers
safely. If no such
collection days are available, think about organizing
one.
Buy limited quantities.
If you use products only occasionally or seasonally,
such as
paints, paint strippers, and kerosene for space
heaters or
gasoline for lawn mowers, buy only as much as
you will use right
away.
Keep exposure to emissions from products containing
methylene
chloride to a minimum.
Consumer products that contain methylene chloride
include paint
strippers, adhesive removers, and aerosol spray
paints. Methylene
chloride is known to cause cancer in animals.
Also, methylene
chloride is converted to carbon monoxide in the
body and can
cause symptoms associated with exposure to carbon
monoxide.
Carefully read the labels containing health hazard
information
and cautions on the proper use of these products.
Use products
that contain methylene chloride outdoors when
possible; use
indoors only if the area is well ventilated.
Keep exposure to benzene to a minimum.
Benzene is a known human carcinogen. The main
indoor sources of
this chemical are environmental tobacco smoke,
stored fuels and
paint supplies, and automobile emissions in attached
garages.
Actions that will reduce benzene exposure include
eliminating
smoking within the home, providing for maximum
ventilation during
painting, and discarding paint supplies and special
fuels that
will not be used immediately.
Keep exposure to perchloroethylene emissions
from newly dry
cleaned materials to a minimum.
Perchloroethylene is the chemical most widely
used in dry
cleaning. In laboratory studies, it has been shown
to cause
cancer in animals. Recent studies indicate that
people breathe
low levels of this chemical both in homes where
dry cleaned goods
are stored and as they wear dry cleaned clothing.
Dry cleaners
recapture the perchloroethylene during the dry
cleaning process
so they can save money by re using it, and
they remove more of
the chemical during the pressing and finishing
processes. Some
dry cleaners, however, do not remove as much perchloroethylene
as
possible all of the time. Taking steps to minimize
your exposure
to this chemical is prudent. If dry cleaned goods
have a strong
chemical odor when you pick them up, do not accept
them until
they have been properly dried. If goods with a
chemical odor are
returned to you on subsequent visits, try a different
dry
cleaner.
FORMALDEHYDE
Formaldehyde is an important chemical used
widely by industry to
manufacture building materials and numerous household
products.
It is also a byproduct of combustion and certain
other natural
processes. Thus, it may be present in substantial
concentrations
both indoors and outdoors.
Sources of formaldehyde in the home include
building
materials, smoking, household products, and the
use of unvented,
fuel burning appliances, like gas stoves or kerosene
space
heaters. Formaldehyde, by itself or in combination
with other
chemicals, serves a number of purposes in manufactured
products.
For example, it is used to add permanent press
qualities to
clothing and draperies, as a component of glues
and adhesives,
and as a preservative in some paints and coating
products.
In homes, the most significant sources of formaldehyde
are likely
to be pressed wood products made using adhesives
that contain
ureaformaldehyde (UF) resins. Pressed wood products
made for
indoor use include: particle board (used as sub
flooring and
shelving and in cabinetry and furniture); hardwood
plywood
paneling (used for decorative wall covering and
used in cabinets
and furniture); and medium density fiberboard
(used for drawer
fronts, cabinets, and furniture tops). Medium
density fiberboard
contains a higher resin to wood ratio than any
other UF pressed
wood product and is generally recognized as being
the highest
formaldehyde emitting pressed wood product.
Other pressed wood products, such as softwood
plywood and flake
or oriented strand board, are produced for exterior
construction
use and contain the dark, or red/black colored
phenolformaldehyde
(PF) resin. Although formaldehyde is present in
both types of
resins, pressed woods that contain PF resin generally
emit
formaldehyde at considerably lower rates than
those containing UF
resin.
Since 1985, the Department of Housing and Urban
Development (HUD)
has permitted only the use of plywood and particle
board that
conform to specified formaldehyde emission limits
in the
construction of prefabricated and mobile homes.
In the past, some
of these homes had elevated levels of formaldehyde
because of the
large amount of high emitting pressed wood products
used in their
construction and because of their relatively small
interior
space.
The rate at which products like pressed wood
or textiles release
formaldehyde can change. Formaldehyde emissions
will generally
decrease as products age. When the products are
new, high indoor
temperatures or humidity can cause increased release
of
formaldehyde from these products.
During the 1970s, many homeowners had ureaformaldehyde
foam
insulation (UFFI) installed in the wall cavities
of their homes
as an energy conservation measure. However, many
of these homes
were found to have relatively high indoor concentrations
of
formaldehyde soon after the UFFI installation.
Few homes are now
being insulated with this product. Studies
(continued on page 23)
show that formaldehyde emissions from UFFI
decline with time;
therefore, homes in which UFFI was installed many
years ago are
unlikely to have high levels of formaldehyde now.
Health Effects of Formaldehyde
Formaldehyde, a colorless, pungent smelling
gas, can cause watery
eyes, burning sensations in the eyes and throat,
nausea, and
difficulty in breathing in some humans exposed
at elevated levels
(above 0.1 parts per million). High concentrations
may trigger
attacks in people with asthma. There is evidence
that some people
can develop a sensitivity to formaldehyde. It
has also been shown
to cause cancer in animals and may cause cancer
in humans.
Reducing Exposure to Formaldehyde in Homes
Ask about the formaldehyde content of pressed
wood products,
including building materials, cabinetry, and furniture
before you
purchase them.
If you experience adverse reactions to formaldehyde,
you may want
to avoid the use of pressed wood products and
other formaldehyde
emitting goods. Even if you do not experience
such reactions, you
may wish to reduce your exposure as much as possible
by
purchasing exterior grade products, which emit
less formaldehyde.
For further information on formaldehyde and consumer
products,
call the EPA Toxic Substance Control Act (TSCA)
assistance line
(2025541404).
Some studies suggest that coating pressed
wood products with
polyurethane may reduce formaldehyde emissions
for some period of
time. To be effective, any such coating must cover
all surfaces
and edges and remain intact. Increase the ventilation
and
carefully follow the manufacturer s instructions
while applying
these coatings. (If you are sensitive to formaldehyde,
check the
label contents before purchasing coating products
to avoid buying
products that contain formaldehyde, as they will
emit the
chemical for a short time after application.)
Maintain moderate temperature and humidity
levels and provide
adequate ventilation.
The rate at which formaldehyde is released
is accelerated by heat
and may also depend somewhat on the humidity level.
Therefore,
the use of dehumidifiers and air conditioning
to control humidity
and to maintain a moderate temperature can help
reduce
formaldehyde emissions. (Drain and clean dehumidifier
collection
trays frequently so that they do not become a
breeding ground for
microorganisms.) Increasing the rate of ventilation
in your home
will also help in reducing formaldehyde levels.
PESTICIDES
According to a recent survey, 75 percent
of U.S. households
used at least one pesticide product indoors during
the past year.
Products used most often are insecticides and
disinfectants.
Another study suggests that 80 90 percent of most
people s
exposure to pesticides occurs indoors and that
measurable
levels of up to a dozen pesticides have been found
in the air
inside homes. The amount of pesticides found in
homes appears to
be greater than can be explained by recent pesticide
use in those
households; other possible sources include contaminated
soil or
dust that floats or is tracked in from outside,
stored pesticide
containers, and household surfaces that collect
and then release
the pesticides. Pesticides used in and around
the home include
products to control insects (insecticides), termites
(termiticides), rodents (rodenticides), fungi
(fungicides), and
microbes (disinfectants). They are sold as sprays,
liquids,
sticks, powders, crystals, balls, and foggers.
In 1990, the American Association of Poison
Control Centers
reported that some 79,000 children were involved
in common
household pesticide poisonings or exposures.
In households with
children under five years old, almost one half
stored at least
one pesticide product within reach of children.
EPA registers pesticides for use and requires
manufacturers to
put information on the label about when and how
to use the
pesticide. It is important to remember that the
"cide" in
pesticides means to kill. These products can
be dangerous if
not used properly.
In addition to the active ingredient, pesticides
are also made up
of ingredients that are used to carry the active
agent. These
carrier agents are called "inerts" in
pesticides because they are
not toxic to the targeted pest; nevertheless,
some inerts are
capable of causing health problems.
Health Effects From Pesticides
Both the active and inert ingredients in pesticides
can be
organic compounds; therefore, both could add to
the levels of
airborne organics inside homes. Both types of
ingredients can
case the effects discussed in this booklet under
Household
Products. However, as with other household products,
there is
insufficient understanding at present about what
pesticide
concentrations are necessary to produce these
effects.
Exposure to high levels of cyclodiene
pesticides, commonly
associated with misapplication, has produced various
symptoms,
including headaches, dizziness, muscle twitching,
weakness,
tingling sensations, and nausea. In addition,
EPA is concerned
that cyclodienes might cause long term damage
to the liver and
the central nervous system, as well as an increased
risk of
cancer.
There is no further sale or commercial use
permitted for the
following cyclodiene or related pesticides: chlordane,
aldrin,
dieldrin, and heptachlor. The only exception
is the use of
heptachlor by utility companies to control fire
ants in
underground cable boxes.
Reducing Exposure to Pesticides in Homes
Read the label and follow the directions.
It is illegal to use
any pesticide in any manner inconsistent with
the directions on
its label.
Unless you have had special training and are
certified, never use
a pesticide that is restricted to use by state
certified pest
control operators. Such pesticides are simply
too dangerous for
application by a non certified person. Use only
the pesticides
approved for use by the general public and then
only in
recommended amounts; increasing the amount does
not offer more
protection against pests and can be harmful to
you and your
plants and pets.
Ventilate the area well after pesticide use.
Mix or dilute pesticides outdoors or in a well
ventilated area
and only in the amounts that will be immediately
needed. If
possible, take plants and pets outside when applying
pesticides
to them.
Use nonchemical methods of pest control when
possible.
Since pesticides can be found far from the
site of their original
application, it is prudent to reduce the use of
chemical
pesticides outdoors as well as indoors. Depending
on the site and
pest to be controlled, one or more of the following
steps can be
effective: use of biological pesticides, such
as Bacillus
thuringiensis, for the control of gypsy moths;
selection of
disease resistant plants; and frequent washing
of indoor plants
and pets. Termite damage can be reduced or prevented
by making
certain that wooden building materials do not
come into direct
contact with the soil and by storing firewood
away from the home.
By appropriately fertilizing, watering, and aerating
lawns, the
need for chemical pesticide treatments of lawns
can be
dramatically reduced.
If you decide to use a pest control company,
choose one
carefully.
Ask for an inspection of your home and get
a written control
program for evaluation before you sign a contract.
The control
program should list specific names of pests to
be controlled and
chemicals to be used; it should also reflect any
of your safety
concerns. Insist on a proven record of competence
and customer
satisfaction.
Dispose of unwanted pesticides safely.
If you have unused or partially used pesticide
containers you
want to get rid of, dispose of them according
to the directions
on the label or on special household hazardous
waste collection
days. If there are no such collection days in
your community,
work with others to organize them.
Keep exposure to moth repellents to a minimum.
One pesticide often found in the home is paradichlorobenzene,
a
commonly used active ingredient in moth repellents.
This chemical
is known to cause cancer in animals, but substantial
scientific
uncertainty exists over the effects, if any, of
long term human
exposure to paradichlorobenzene. EPA requires
that products
containing paradichlorobenzene bear warnings such
as avoid
breathing vapors to warn users of potential short
term toxic
effects. Where possible, paradichlorobenzene,
and items to be
protected against moths, should be placed in trunks
or other
containers that can be stored in areas that are
separately
ventilated from the home, such as attics and detached
garages.
Paradichlorobenzene is also the key active ingredient
in many air
fresheners (in fact, some labels for moth repellents
recommend
that these same products be used as air fresheners
or
deodorants). Proper ventilation and basic household
cleanliness
will go a long way toward preventing unpleasant
odors.
Call the National Pesticide Telecommunications
Network (NPTN).
EPA sponsors the NPTN (800-858-PEST) to answer
your questions
about pesticides and to provide selected EPA publications
on
pesticides.
ASBESTOS
Asbestos is a mineral fiber that has been used
commonly in a
variety of building construction materials for
insulation and as
a fire retardant. EPA and CPSC have banned several
asbestos
products. Manufacturers have also voluntarily
limited uses of
asbestos. Today, asbestos is most commonly found
in older homes,
in pipe and furnace insulation materials, asbestos
shingles, mill
board, textured paints and other coating materials,
and floor
tiles.
Elevated concentrations of airborne asbestos
can occur after
asbestos containing materials are disturbed by
cutting, sanding
or other remodeling activities. Improper attempts
to remove these
materials can release asbestos fibers into the
air in homes,
increasing asbestos levels and endangering people
living in those
homes.
Health Effects of Asbestos
The most dangerous asbestos fibers are too
small to be visible.
After they are inhaled, they can remain and accumulate
in the
lungs. Asbestos can cause lung cancer, mesothelioma
(a cancer of
the chest and abdominal linings), and asbestosis
(irreversible
lung scarring that can be fatal). Symptoms of
these diseases do
not show up until many years after exposure began.
Most people
with asbestos related diseases were exposed to
elevated
concentrations on the job; some developed disease
from exposure
to clothing and equipment brought home from job
sites.
Reducing Exposure to Asbestos in Homes
Learn how asbestos problems are created in
homes. Read the
booklet, Asbestos in Your Home, issued by CPSC,
the ALA, and EPA.
To contact these organizations, see the section,
Where to Go For
More Information.
If you think your home may have asbestos,
don t panic!
Usually it is best to leave asbestos material
that is in good
condition alone. Generally, material in good
condition will not
release asbestos fiber. There is no danger unless
fibers are
released and inhaled into the lungs.
Do not cut, rip, or sand asbestos containing
materials.
Leave undamaged materials alone and, to the
extent possible,
prevent them from being damaged, disturbed, or
touched.
Periodically inspect for damage or deterioration.
Discard damaged
or worn asbestos gloves, stove top pads, or
ironing board
covers. Check with local health, environmental,
or other
appropriate officials to find out about proper
handling and
disposal procedures.
If asbestos material is more than slightly
damaged, or if
you are going to make changes in your home that
might disturb it,
repair or removal by a professional is needed.
Before you have
your house remodeled, find out whether asbestos
materials are
present.
When you need to remove or clean up asbestos,
use a
professionally trained contractor.
Select a contractor only after careful discussion
of the problems
in your home and the steps the contractor will
take to clean up
or remove them. Consider the option of sealing
off the materials
instead of removing them.
Call EPA s TSCA assistance line (2025541404)
to find out
whether your state has a training and certification
program for
asbestos removal contractors and for information
on EPA s
asbestos programs.
LEAD
Lead has long been recognized as a harmful
environmental
pollutant. In late 1991, the Secretary of the
Department of
Health and Human Services called lead the number
one
environmental threat to the health of children
in the United
States. There are many ways in which humans are
exposed to lead:
through air, drinking water, food, contaminated
soil,
deteriorating paint, and dust. Airborne lead enters
the body when
an individual breathes or swallows lead particles
or dust once it
has settled. Before it was known how harmful lead
could be, it
was used in paint, gasoline, water pipes, and
many other
products.
Old lead based paint is the most significant
source of lead
exposure in the U.S. today. Harmful exposures
to lead can be
created when lead based paint is improperly removed
from surfaces
by dry scraping, sanding, or open flame burning.
High
concentrations of airborne lead particles in homes
can also
result from lead dust from outdoor sources, including
contaminated soil tracked inside, and use of lead
in certain
indoor activities such as soldering and stained
glass making.
Health Effects of Exposure to Lead
Lead affects practically all systems within
the body. At high
levels it can cause convulsions, coma, and even
death. Lower
levels of lead can adversely affect the brain,
central nervous
system, blood cells, and kidneys.
The effects of lead exposure on fetuses
and young children
can be severe. They include delays in physical
and mental
development, lower IQ levels, shortened attention
spans, and
increased behavioral problems. Fetuses, infants,
and children
are more vulnerable to lead exposure than adults
since lead is
more easily absorbed into growing bodies, and
the tissues of
small children are more sensitive to the damaging
effects of
lead. Children may have higher exposures since
they are more
likely to get lead dust on their hands and then
put their fingers
or other lead contaminated objects into their
mouths.
Get your child tested for lead exposure. To
find out where to do
this, call your doctor or local health clinic.
For more
information on health effects, get a copy of the
Centers for
Disease Control s, Preventing Lead Poisoning in
Young Children
(October 1991).
Ways to Reduce Exposure to Lead
Keep areas where children play as dust free
and clean as
possible.
Mop floors and wipe window ledges and chewable
surfaces such as
cribs with a solution of powdered automatic dishwasher
detergent
in warm water. (Dishwasher detergents are recommended
because of
their high content of phosphate.) Most multipurpose
cleaners
will not remove lead in ordinary dust. Wash toys
and stuffed
animals regularly. Make sure that children wash
their hands
before meals, nap time, and bedtime.
Reduce the risk from lead based paint.
Most homes built before 1960 contain heavily
leaded paint. Some
homes built as recently as 1978 may also contain
lead paint. This
paint could be on window frames, walls, the outside
of homes, or
other surfaces. Do not burn painted wood since
it may contain
lead.
Leave lead based paint undisturbed if it is
in good condition do
not sand or burn off paint that may contain lead.
Lead paint in good condition is usually not
a problem except in
places where painted surfaces rub against each
other and create
dust (for example, opening a window).
Do not remove lead paint yourself.
Individuals have been poisoned by scraping
or sanding lead paint
because these activities generate large amounts
of lead dust.
Consult your state health or housing department
for suggestions
on which private laboratories or public agencies
may be able to
help test your home for lead in paint. Home test
kits cannot
detect small amounts of lead under some conditions.
Hire a
person with special training for correcting lead
paint problems
to remove lead based paint. Occupants, especially
children and
pregnant women, should leave the building until
all work is
finished and cleanup is done.
For additional information dealing with
lead based paint
abatement contact the Department of Housing and
Urban Development
for the following two documents: Comprehensive
and Workable Plan
for the Abatement of Lead Based Paint in Privately
Owned Housing:
Report to Congress (December 7, 1990) and Lead
Based Paint:
Interim Guidelines for Hazard Identification and
Abatement in
Public and Indian Housing (September 1990).
Do not bring lead dust into the home.
If you work in construction, demolition, painting,
with
batteries, in a radiator repair shop or lead factory,
or your
hobby involves lead, you may unknowingly bring
lead into your
home on your hands or clothes. You may also be
tracking in lead
from soil around your home. Soil very close to
homes may be
contaminated from lead paint on the outside of
the building.
Soil by roads and highways may be contaminated
from years of
exhaust fumes from cars and trucks that used leaded
gas. Use door
mats to wipe your feet before entering the home.
If you work with
lead in your job or a hobby, change your clothes
before you go
home and wash these clothes separately. Encourage
your children
to play in sand and grassy areas instead of dirt
which sticks to
fingers and toys. Try to keep your children from
eating dirt,
and make sure they wash their hands when they
come inside.
Find out about lead in drinking water.
Most well and city water does not usually contain
lead. Water
usually picks up lead inside the home from household
plumbing
that is made with lead materials. The only way
to know if there
is lead in drinking water is to have it tested.
Contact the
local health department or the water supplier
to find out how to
get the water tested. Send for the EPA pamphlet,
Lead and Your
Drinking Water, for more information about what
you can do if you
have lead in your drinking water. Call EPA s
Safe Drinking Water
Hotline (8004264791) for more information.
Eat right.
A child who gets enough iron and calcium will
absorb less lead.
Foods rich in iron include eggs, red meats, and
beans. Dairy
products are high in calcium. Do not store food
or liquid in
lead crystal glassware or imported or old pottery.
If you reuse
old plastic bags to store or carry food, keep
the printing on the
outside of the bag.
You can get a brochure, Lead Poisoning
and Your Children,
and more information by calling the National Lead
Information
Center, 800-LEAD-FYI.
Building a new home provides the opportunity
for preventing
indoor air problems. However, it can result in
exposure to
higher levels of indoor air contaminants if
careful attention
is not given to potential pollution sources and
the air exchange
rate.
Express your concerns about indoor air
quality to your
architect or builder and enlist his or her cooperation
in taking
measures to provide good indoor air quality. Talk
both about
purchasing building materials and furnishings
that are low
emitting and about providing an adequate amount
of ventilation.
The American Society of Heating, Refrigerating,
and Air
Conditioning Engineers recommends a ventilation
rate of 0.35 ach
(air changes per hour) for new homes, and some
new homes are
built to even tighter specifications. Particular
care should be
given in such homes to preventing the buildup
of indoor air
pollutants to high levels.
Here are a few important actions that can make
a difference:
Use radon resistant construction techniques.
Obtain a copy of the EPA booklet, Radon Resistant
Construction
Techniques for Residential Construction, from
your state radon
office or health agency, your state homebuilders
association, or
your EPA regional office.
Choose building materials and furnishings
that will keep indoor
air pollution to a minimum.
There are many actions a homeowner can take
to select products
that will prevent indoor air problems from occurring
a couple of
them are mentioned here. First, use exterior grade
pressed wood
products made with phenolformaldehyde resin in
floors, cabinetry,
and wall surfaces. Or, as an alternative, consider
using solid
wood products. Secondly, if you plan to install
wall to wall
carpet on concrete in contact with the ground,
especially
concrete in basements, make sure that an effective
moisture
barrier is installed prior to installing the carpet.
Do not
permanently adhere carpet to concrete with adhesives
so that the
carpet can be removed if it becomes wet.
_Provide proper drainage and seal foundations
in new
construction.
Air that enters the home through the foundation
can contain more
moisture than is generated from all occupant activities.
Become familiar with mechanical ventilation
systems and consider
installing one.
Advanced designs of new homes are starting
to feature mechanical
systems that bring outdoor air into the home.
Some of these
designs include energy efficient heat recovery
ventilators (also
known as air to air heat exchangers).
Ensure that combustion appliances, including
furnaces,
fireplaces, wood stoves, and heaters, are properly
vented and
receive enough supply air.
Combustion gases, including carbon monoxide,
and particles can be
back drafted from the chimney or flue into the
living space if
the combustion appliance is not properly vented
or does not
receive enough supply air. Back drafting can
be a particular
problem in weatherized or tightly constructed
homes. Installing
a dedicated outdoor air supply for the combustion
appliance can
help prevent back drafting.
Indoor air quality problems are not limited
to homes. In fact,
many office buildings have significant air pollution
sources.
Some of these buildings may be inadequately ventilated.
For
example, mechanical ventilation systems may not
be designed or
operated to provide adequate amounts of outdoor
air. Finally,
people generally have less control over the indoor
environment in
their offices than they do in their homes. As
a result, there
has been an increase in the incidence of reported
health
problems.
HEALTH EFFECTS
A number of well identified illnesses, such
as Legionnaire s
disease, asthma, hypersensitivity pneumonitis,
and humidifier
fever, have been directly traced to specific building
problems.
These are called building related illnesses.
Most of these
diseases can be treated nevertheless, some pose
serious risks.
Sometimes, however, building occupants
experience symptoms
that do not fit the pattern of any particular
illness and are
difficult to trace to any specific source. This
phenomenon has
been labeled sick building syndrome. People may
complain of one
or more of the following symptoms: dry or burning
mucous
membranes in the nose, eyes, and throat; sneezing;
stuffy or
runny nose; fatigue or lethargy; headache; dizziness;
nausea;
irritability an forgetfulness. Poor lighting,
noise, vibration,
thermal discomfort, and psychological stress may
also cause, or
contribute to, these symptoms.
There is no single manner in which these health
problems appear.
In some cases, problems begin as workers enter
their offices and
diminish as workers leave; other times, symptoms
continue until
the illness is treated. Sometimes there are outbreaks
of illness
among many workers in a single building; in other
cases, health
symptoms show up only in individual workers.
In the opinion of some World Health Organization
experts, up to
30 percent of new or remodeled commercial buildings
may have
unusually high rates of health and comfort complaints
from
occupants that may potentially be related to indoor
air quality.
WHAT CAUSES PROBLEMS?
Three major reasons for poor indoor air quality
in office
buildings are the presence of indoor air pollution
sources;
poorly designed, maintained, or operated ventilation
systems; and
uses of the building that were unanticipated or
poorly planned
for when the building was designed or renovated.
Sources of Office Air Pollution
As with homes, the most important factor influencing
indoor air
quality is the presence of pollutant sources.
Commonly found
office pollutants and their sources include environmental
tobacco
smoke; asbestos from insulating and fire retardant
building
supplies; formaldehyde from pressed wood products;
other organics
from building materials, carpet, and other office
furnishings,
cleaning materials and activities, rest room air
fresheners,
paints, adhesives, copying machines, and photography
and print
shops; biological contaminants from dirty ventilation
systems or
water damaged walls, ceilings, and carpets; and
pesticides from
pest management practices.
Ventilation Systems
Mechanical ventilation systems in large buildings
are designed
and operated not only to heat and cool the air,
but also to draw
in and circulate outdoor air. If they are poorly
designed,
operated, or maintained, however, ventilation
systems can
contribute to indoor air problems in several ways.
For example, problems arise when, in an
effort to save
energy, ventilation systems are not used to bring
in adequate
amounts of outdoor air. Inadequate ventilation
also occurs if the
air supply and return vents within each room are
blocked or
placed in such a way that outdoor air does not
actually reach the
breathing zone of building occupants. Improperly
located outdoor
air intake vents can also bring in air contaminated
with
automobile and truck exhaust, boiler emissions,
fumes from
dumpsters, or air vented from rest rooms. Finally,
ventilation
systems can be a source of indoor pollution themselves
by
spreading biological contaminants that have multiplied
in cooling
towers, humidifiers, dehumidifiers, air conditioners,
or the
inside surfaces of ventilation duct work.
Use of the Building
Indoor air pollutants can be circulated from
portions of the
building used for specialized purposes, such as
restaurants,
print shops, and dry cleaning stores, into offices
in the same
building. Carbon monoxide and other components
of automobile
exhaust can be drawn from underground parking
garages through
stairwells and elevator shafts into office spaces.
In addition, buildings originally designed
for one purpose
may end up being converted to use as office space.
If not
properly modified during building renovations,
the room
partitions and ventilation system can contribute
to indoor air
quality problems by restricting air recirculation
or by providing
an inadequate supply of outdoor air.
WHAT TO DO IF YOU SUSPECT A PROBLEM
If you or others at your office are experiencing
health or
comfort problems that you suspect may be caused
by indoor air
pollution, you can do the following:
Talk with other workers, your supervisor,
and union
representatives to see if the problems are being
experienced by
others and urge that a record of reported health
complaints be
kept by management, if one has not already been
established.
Talk with your own physician and report your
problems to the
company physician, nurse, or health and safety
officer.
Call your state or local health department
or air pollution
control agency to talk over the symptoms and possible
causes.
Encourage building management to obtain a
copy of Building Air
Quality: A Guide for Building Owners and Facility
Managers.
Building Air Quality (BAQ) is simply written,
yet provides
comprehensive information for identifying, correcting,
and
preventing indoor air quality problems. BAQ also
provides
supporting information such as when and how to
select outside
technical assistance, how to communicate with
others regarding
indoor air issues, and where to find additional
sources of
information. BAQ is available for $24 from U.S.
GPO,
Superintendent of Documents, P.O. Box 371954,
Pittsburgh, PA
152507954; stock #055000003904.
Frequently, indoor air quality problems in
large commercial
buildings cannot be effectively identified or
remedied without a
comprehensive building investigation. These investigations
may
start with written questionnaires and telephone
consultations in
which building investigators assess the history
of occupant
symptoms and building operation procedures. In
some cases, these
inquiries may quickly uncover the problem and
on site visits are
unnecessary.
More often, however, investigators will need
to come to the
building to conduct personal interviews with occupants,
to look
for possible sources of the problems, and to inspect
the design
and operation of the ventilation system and other
building
features. Because taking measurements of pollutants
at the very
low levels often found in office buildings is
expensive and may
not yield information readily useful in identifying
problem
sources, investigators may not take many measurements.
The
process of solving indoor air quality problems
that result in
health and comfort complaints can be a slow one,
involving
several trial solutions before successful remedial
actions are
identified.
If a professional company is hired to conduct
a building
investigation, select a company on the basis of
its experience in
identifying and solving indoor air quality problems
in
nonindustrial buildings.
Work with others to establish a smoking policy
that eliminates
involuntary nonsmoker exposure to environmental
tobacco smoke.
Call the National Institute for Occupational
Safety and Health
(NIOSH) for information on obtaining a health
hazard evaluation
of your office (800-35-N-EACH), or contact the
Occupational
Safety and Health Administration, (202) 2198151.
Federal Information Services
Federal agencies with indoor air quality information
may be
contacted as follows:
U.S. Environmental Protection Agency (EPA)
Public Information Center
401 M St., SW
Washington, DC 20460
(202) 260-7751
Indoor Air Quality Information Clearinghouse
(IAQ INFO)
P.O. Box 37133
Washington, DC 200137133
(800) 438-4318
(301) 585-9020
Operates Monday to Friday from 9 to 5 Eastern
Standard Time
(EST). Distributes EPA publications, answers questions
on the
phone, and makes referrals to other nonprofit
and governmental
organizations.
National Radon Hotline
(800) SOS-RADON
Information recording operates 24 hours a day.
National Lead Information Center
(800) LEAD-FYI
Operates 24 hours a day, seven days a week.
Callers may order an
information package. To speak to an information
specialist, call
(800)4245323. Operates Monday to Friday from
8:30 to 5 EST.
National Pesticides Telecommunications Network
National toll free number: (800) 858-PEST
In Texas: (806) 7433091
Operates Monday to Friday from 8 to 6 Central
Standard Time.
Provides information about pesticides to the general
public and
the medical, veterinary, and professional communities.
RCRA/Super fund Hotline
National toll free number: (800) 4249346
In Washington, DC area: (703) 4129810
Operates Monday to Friday from 8:30 to 7:30
EST. Provides
information on regulations under both the Resources
Conservation
and Recovery Act (including solid and hazardous
waste issues) and
the Superfund law.
Safe Drinking Water Hotline
(800) 4264791
Operates Monday to Friday from 8:30 to 5 EST.
Provides
information on regulations under the Safe Drinking
Water Act,
lead and radon in drinking water, filter information,
and a
list of state drinking water offices.
TSCA Assistance Information Service
(202) 5541404
Operates Monday to Friday from 8:30 to 5 EST.
Provides
information on regulations under the Toxic Substances
Control Act
and on EPA's asbestos program.
U.S. Consumer Product Safety Commission (CPSC)
Washington, DC 202070001
Product Safety Hotline: (800) 638-CPSC
Teletypewriter for the hearing impaired (outside
Maryland): (800)
638-8270; Maryland only: (800) 492-8104. Recorded
information is
available 24 hours a day when calling from a touch
tone phone.
Operators are on duty Monday to Friday from 10:30
to 4 EST to
take complaints about unsafe consumer products.
U.S. Department of Housing and Urban Development
Office of Energy and the Environment
Washington, DC 20410
HUD USER National toll free number: (800) 245-2691
In Washington, DC area: (301) 251-5154.
U.S. Department of Energy
Office of Conservation and Renewable Energy
1000 Independence Ave., SW
Washington, DC 20585
Conservation and Renewable Energy Inquiry and
Referral Service
(CAREIRS)
PO Box 3048, Merrifield, VA 22116; (800) 523-2929.
Operates Monday to Friday from 9 to 5 EST.
Provides consumer
information on conservation and renewable energy
in residences.
U.S. Public Health Service
Division of Federal Occupational Health
Office of Environmental Hygiene, Region III, Room
1310
3535 Market St., Philadelphia, PA 19104
(215) 596-1888; fax: 215-596-5024
Provides indoor air quality consultative services
to federal
agency managers.
Centers for Disease Control and Prevention
Lead Poisoning Prevention Branch
4770 Buford Highway, NE (F42), Atlanta, GA 30341-3724
(800) 488-7330
Office on Smoking and Health
Centers for Disease Control and Prevention
U.S. Department of Health and Human Services
4770 Buford Highway, NE (K50), Atlanta, GA
30341-3724
(404) 488-5701
Occupational Safety and Health Administration
Office of Information and Consumer Affairs
Room N-3647
200 Constitution Avenue, NW, Washington, DC 20210
(202) 219-8151
Bonneville Power Administration
Portland, OR 97208
General Services Administration
18th and F Streets, NW, Washington, DC 20405
Tennesee Valley Authority
Industrial Hygiene Branch
Multipurpose Building (1B), Muscle Shoals,
AL 35660
State and Local Organizations
Your questions or concerns about indoor air
problems can
frequently be answered by the government agencies
in your state
or local government. Responsibilities or indoor
air quality
issues are usually divided among many different
agencies. Calling
or writing the agencies responsible for health
or air quality
control is the best way to start getting information
from your
state or local government. To obtain state agency
contacts, write
or call EPA s IAQ Information Clearinghouse, (800)
4384318.
CPSC REGIONAL OFFICES
Eastern Regional Center
6 World Trade Center
Vesey Street, 3rd Floor Room 350
New York, NY 10048-0950
(212) 466-1612
Central Regional Center
230 South Dearborn Street Room 2944
Chicago, IL 60604-1601
(312) 353-8260
Western Regional Center
600 Harrison Street Room 245
San Francisco, CA 94107
(415) 744-2966
States in Region
Connecticut, District of Columbia, Delaware, Florida,
Massachusetts, Maryland, Maine, North Carolina,
New Hampshire,
New York, Pennsylvania, South Carolina, Rhode
Island, Virginia,
Vermont, West Virginia
Alabama, Georgia, Iowa, Illinois, Indiana,
Kansas, Kentucky,
Michigan, Minnesota, Missouri, Mississippi, North
Dakota,
Nebraska, Ohio, South Dakota, Tennessee, Wisconsin
Alaska, Arkansas, Arizona, California, Colorado,
Hawaii, Idaho,
Louisiana, Montana, New Mexico, Nevada, Oklahoma,
Oregon, Texas,
Utah, Washington, Wyoming
EPA REGIONAL OFFICES
Address inquiries to the Indoor Air Coordinators
in the EPA
regional offices at the following addresses:
Region 1
EPA
John F. Kennedy Federal Building
Boston, MA 02203
617-565-4502
Region 2
EPA (2AWM-RAD)
26 Federal Plaza
New York, NY 10278
212-264-4418
Region 3
EPA
841 Chestnut Building
Philadelphia, PA 19107
215-595-8322
215-597-4084 (radon)
Region 4
EPA
345 Courtland Street NE
Atlanta, GA 30365
404-347-2864
Region 5
EPA AT-18L
77 W. Jackson Blvd.
Chicago, IL 60604
312-353-2205
Region 6
EPA
First Interstate Bank Tower
1445 Ross Avenue
Dallas, TX 75202
214-655-7223
Region 7
EPA ARTX / ARBR-RAID
726 Minnesota Avenue
Kansas City, KS 66101
913-551-7222
Region 8
EPA 999 18th Street, Suite 500
Denver, CO 80202-2466
303-293-1709
The following organizations have information
discussed in this
booklet. EPA s IAQ Information Clearinghouse,
(800)438-4318, can
provide the names of a variety of organizations
that have
information on all of the issues discussed in
this publication.
American Association of Poison Control Centers
3800 Reservoir Rd., NW
Washington, DC 20007
American Society of Heating, Refrigerating,
and Air-Conditioning
(ASHRAE)
1791 Tullie Circle NE
Atlanta, GA 30329
World Health Organization
Publications Center
49 Sheridan Avenue
Albany, NY 12210
Your local American Lung Association (ALA)
1740 Broadway
New York, NY 10019
(800) LUNG-USA
GLOSSARY
Acid aerosol
Acidic liquid or solid particles that are small
enough to become
airborne. High concentrations of acid aerosols
can be irritating
to the lungs and have been associated with some
respiratory
diseases, such as asthma.
Animal dander
Tiny scales of animal skin.
Allergen
A substance capable of causing an allergic reaction
because of an
individual s sensitivity to that substance.
Allergic rhinitis
Inflammation of the mucous membranes in the nose
that is caused
by an allergic reaction.
Building-related illness
A discrete, identifiable disease or illness that
can be traced to
a specific pollutant or source within a building.
(Contrast with
Sick building syndrome ).
Chemical sensitization
Evidence suggests that some people may develop
health problems
characterized by effects such as dizziness, eye
and throat
irritation, chest tightness, and nasal congestion
that appear
whenever they are exposed to certain chemicals.
People may react
to even trace amounts of chemicals to which they
have become
sensitized.
Environmental tobacco smoke
Mixture of smoke from the burning end of a cigarette,
pipe, or
cigar and smoke exhaled by the smoker (also secondhand
smoke or
passive smoking).
Fungi
Any of a group of parasitic lower plants that
lack chlorophyll,
including molds and mildews.
Humidifier fever
A respiratory illness caused by exposure to toxins
from
microorganisms found in wet or moist areas in
humidifiers and air
conditioners. Also called air conditioner or
ventilation fever.
Hypersensitivity pneumonitis
A group of respiratory diseases that cause inflammation
of the
lung (specifically granulomatous cells). Most
forms of
hypersensitivity pneumon-itis are caused by the
inhalation of
organic dusts, including molds.
Organic compounds
Chemicals that contain carbon. Volatile organic
compounds
vaporize at room temperature and pressure. They
are found in
many indoor sources, including many common household
products and
building materials.
Picocurie
A unit for measuring radioactivity, often expressed
as picocuries
per liter of air.
Pressed wood products
A group of materials used in building and furniture
construction
that are made from wood veneers, particles, or
fibers bonded
together with an adhesive under heat and pressure.
Radon and radon decay products
Radon is a radioactive gas formed in the decay
of uranium. The
radon decay products (also called radon daughters
or progeny) can
be breathed into the lung where they continue
to release
radiation as they further decay.
Sick building syndrome
Term that refers to a set of symptoms that affect
some number of
building occupants during the time they spend
in the building and
diminish or go away during periods when they leave
the building.
Cannot be traced to specific pollutants or sources
within the
building. (Contrast with Building related illness
).
Ventilation rate
The rate at which indoor air enters and leaves
a building.
Expressed in one of two ways: the number of changes
of outdoor
air per unit of time (air changes per hour, or
ach ) or the rate
at which a volume of outdoor air enters per unit
of time (cubic
feet per minute, or cfm )
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