Toxic Chemicals in Our Environment
Indoor air pollution
Indoor air pollution can
affect you at home, work, or even places you visit. It is a common source of
respiratory diseases, including
asthma, allergies, and lung cancer. It can be worse in
winter, when windows are shut tight and less fresh air can circulate.
See
tips for reducing indoor air pollution, such as not allowing anyone to smoke
in your home.
Cigarette smoke
One of the most common and toxic indoor air pollutants is
cigarette smoke. Experts believe about 90% of lung cancers
are caused by cigarette smoke.1 Smoking, or even
inhaling
secondhand smoke, increases your risk of
heart attack and
stroke.
Tobacco smoke contains many chemicals, some of which are known to cause cancer. If you are a
nonsmoker and household members or coworkers will not stop smoking around you,
ask that they smoke only in well-ventilated or isolated areas. Never smoke
around children or allow them to be exposed to cigarette smoke, especially if
they have asthma or allergies.
Exposure to cigarette
smoke causes wheezing, coughing, and extra mucus (phlegm) in many children.
Secondhand smoke also can cause fluid to build up in the inner ear, which can
cause
ear infections. Lower respiratory infections, such as
pneumonia and
bronchitis, are also risks. Sometimes these types of
infections become serious enough to require a hospital stay, especially when
they develop in babies and young children.2
Babies who are exposed to secondhand smoke are at increased risk for
sudden infant death syndrome (SIDS).3
Cigarette smoke may cause asthma in children.3 Also, children with
asthma who are exposed to cigarette smoke have more attacks and more severe
symptoms than other children with asthma.3
See information on the
increased impact of environmental illnesses on children. For example, in recent years, the number of children with
asthma has more than doubled, and environmental causes are suspected.
Woodstoves and gas ranges
Woodstoves that are not properly maintained and vented
can give off tiny particles (particulates) and gases, including
carbon monoxide, nitrogen, and
hydrocarbons. Children in homes heated with woodstoves are at increased risk
for respiratory problems. Gas ranges, particularly when they are not
well-vented or when they are used as a source of heat, may produce nitrogen
dioxide, which can cause respiratory problems. Consider changing to an electric
stove.
If your gas stove has a persistent yellow flame, it may be
improperly adjusted. Ask your gas company to adjust the burners so the flame
tips are blue. If you're planning to buy a new gas range or stove, consider one
that does not use a pilot light.
If you use a woodstove, make sure
the stove doors fit tightly. Burn only aged or cured wood that is completely dry.
Never burn pressure-treated wood because it is treated with chemicals.
Have chimneys, flues, and furnaces inspected each year.
For
more information, see the topic
Carbon Monoxide Poisoning.
Building materials
Exposure to building materials, products used for home
improvement, and textiles can cause health problems. For example,
particleboard, insulation, carpet adhesives, and other household products emit
formaldehyde, which can cause nausea, respiratory problems, dry or inflamed
skin, and eye irritation. Newly built homes and the confined spaces of mobile
homes can be a particular problem. Using environmentally safe products—such as
paint that contains a low level of or no
volatile organic compounds (VOCs)—can reduce the
chemical load on your body.
Sick building syndrome and building-related asthma
Experts coined the term "sick building syndrome" to
describe acute symptoms that occur only during time spent in a particular
building and that cannot be explained by any specific illness or cause.
Symptoms include headache, dry cough, dry or itchy skin, dizziness, nausea,
difficulty concentrating, fatigue, sensitivity to odors, and irritation of the
eyes, nose, or throat. Typically the symptoms improve after you leave the
building.
Poor ventilation that restricts fresh air flow inside
can be a cause of sick building syndrome. Carpet, adhesives, upholstery,
manufactured wood, pesticides, and cleaning fluids can give off
volatile organic compounds (VOCs), including
formaldehyde. High concentrations of VOCs can cause cancer. Unvented gas and
kerosene space heaters, woodstoves, fireplaces, and gas stoves can produce
carbon monoxide and nitrogen dioxide.
Outdoor sources of
chemicals can also cause sick building syndrome. Pollutants from cars and
trucks and exhaust from plumbing vents and building machinery can enter a
building through vents.
Building-related asthma is
the term used when symptoms of a diagnosed illness can be linked directly to
airborne contaminants within a building. Symptoms include cough, chest
tightness, and wheezing. Leaving the building may not immediately improve the
symptoms.
Bacteria, molds, viruses, and other biological contaminants
Bacteria and molds can breed in stagnant water
that builds up in humidifiers, drain pans, and ducts, or where water collects
on carpet, ceiling tiles, and insulation. Humidifier fever is an illness caused
by
toxins from microorganisms that grow not only in large heating
and cooling systems in buildings but also in home systems
and humidifiers. Legionella pneumophila is an indoor
bacterium that can cause
Legionnaires' disease.
Some viruses can survive on household surfaces, such as counters or floors, or they can get spread through the air when an infected person sneezes or coughs. You can help control viruses by:
- Cleaning household surfaces with a disinfectant.
- Having adequate ventilation in your house.
- Having anyone with a viral infection, such as a cold or the flu, cough or sneeze into the bend of the elbow or into a tissue.
Pet dander
, pollen,
dust mites, molds, and rat and mouse urine are
allergens that can cause asthma,
allergic rhinitis, and other lung problems. Symptoms
of illness caused by biological contaminants include sneezing, watery eyes,
shortness of breath, lethargy, dizziness, and digestive problems.
Exposure early in
life to indoor allergens such as molds may increase the risk of allergies or asthma.4Allergies to molds can also make asthma attacks worse
or cause other breathing problems.
Keep your home clean and as free from dust as possible to
help reduce allergens. There are many ways to
control dust and dust mites in your home, such as
washing bedding in hot water to kill dust mites and eliminating furnishings,
such as drapes, that collect dust. Also, there are many steps you can take
to control
animal dander and other pet allergens.
Exhaust fans that vent to the outdoors and are installed in kitchens and
bathrooms can help get rid of moisture that allows microorganisms, including
molds, to grow. When modern building materials get wet, they provide an ideal
place for the growth of molds, which can make asthma attacks worse and
may cause other respiratory symptoms. Ventilating attic and crawl spaces and
keeping humidity levels below 50% can help prevent moisture buildup in building
materials. There are other ways to
control indoor molds, such as preventing leakage,
removing wet materials, storing fireplace wood outside the home, and using a
dehumidifier during humid weather.
Keep humidifiers clean and
refill them daily with fresh water. Frequently clean evaporation trays in air
conditioners, dehumidifiers, and refrigerators. Water-damaged carpets and
building materials can also have molds and bacteria in them. It is difficult to
get rid of bacteria or molds. So, if possible, replace or remove water-damaged
items from your home.
You can also:
- Remove carpets and replace them with
hardwood or tile floor.
- Have sofas with covers that can be removed
and washed.
- Use blinds instead of drapes, because they collect less
dust.
- Have air filters in some rooms, especially in the
bedroom.
For more information, see:
-
Allergies: Avoiding Indoor Triggers.
Household products
Many of the products you use to clean your home or use
for hobbies and home improvement projects contain potentially hazardous
chemicals. Some can be toxic and in sufficient doses can cause eye and
respiratory problems, headaches, dizziness, visual problems, and memory
impairment. One of the most important ways you can protect yourself is by
following the instructions on the label. When you use cleaning or other products,
be sure to open windows or use an exhaust fan to provide good ventilation.
Never mix household chemicals, such as chlorine bleach and ammonia. Some mixtures can
create toxic fumes that can be fatal.
It's better to use
environmentally safe products. Vinegar, lemon juice,
boric acid, or baking soda can be used instead of store-bought household
cleaners. And they are less damaging to you and to the environment.
Be especially careful with products containing methylene chloride,
including paint strippers, adhesive removers, and aerosol spray paints. If you
use products that contain this chemical, make sure you have adequate
ventilation or use them outdoors, if possible. Also, wear gloves to avoid skin
contact. But whenever you can, use environmentally safe products
instead.
Avoid exposure to benzene, which can cause cancer.
Benzene is found in tobacco smoke, stored fuels, paint supplies, and vehicle
exhaust. Also, try to limit your exposure to newly dry-cleaned
clothing or furnishings. Dry-cleaned goods may emit perchloroethylene (also known
as tetrachloroethylene) and trichloroethylene. These chemicals may cause skin
rashes, headaches, and dizziness5. If your clothes emit a strong odor when you pick them up from
the cleaners, they may not have been dried properly and can release more of
this chemical. After removing the protective plastic from the clothes, hang
them outside, if possible. Consider finding a dry cleaner that uses less toxic
chemicals.
Asbestos
Asbestos is an insulating material commonly used from the
1950s to 1970s for soundproofing and to cover floors and ceilings, water pipes,
and heating ducts. When it becomes crumbly or frayed, asbestos fibers can be released
into the air. Breathing asbestos fibers may cause
lung cancer, asbestosis (scarring of the lung tissue), or
mesothelioma.
Radon
Radon is a colorless, odorless radioactive gas that can
enter your home through cracks in concrete walls and floors and through floor
drains. The most common source of radon is uranium that normally exists in the
soil or rock on which homes are built. Problems show up when the concentration of
radon builds up in a home or building. Both old or new homes can have problems
with radon even if they don't have a basement.
Exposure to radon
gas is the second leading cause of lung cancer. (Tobacco smoke is the leading
cause.) The risk of
radon-associated lung cancer is
much higher for smokers than nonsmokers.6
You cannot smell or see radon. But it's
easy to test for it with a do-it-yourself kit available in hardware stores or
through the U.S. Environmental Protection Agency (EPA). For more information,
see the topic
Radon.
Treatment for indoor air pollution
How you react to indoor air pollutants
depends on your age, health, and how sensitive you are to certain chemicals or
biological pollutants, such as bacteria or molds. Treatment can be as simple as removing
and limiting your exposure to
toxic chemicals in your home. In some cases, serious
illnesses—such as cancer, heart disease, and respiratory disease—can develop
after long-term and repeated exposures. With such long-term exposures,
treatment may be extensive, depending on the type of illness.
Outdoor air pollution
Polluted air comes from many
sources, such as factories, cars, buses, trucks, and power plants. And there
are other sources that you may not think of, such as dry cleaners, wildfires,
and dust. Dirty air is a threat to your health. And it also damages crops,
trees, water, and animals.
There are at least six major components of air
pollution:
-
Ozone. Ozone is a gas
that exists at ground level as well as miles above the earth. It's made by a
chemical reaction between nitrogen oxides and
volatile organic compounds (VOCs) in the presence of
heat and sunlight. "Good" ozone occurs naturally about 10 to 30 miles above the
earth's surface. There, in the stratosphere, it forms a layer that protects the earth's surface from
the sun's harmful rays. At ground level, "bad" ozone (smog) exists. Exhaust
from vehicles, industrial emissions, gasoline vapors, and chemical solvents are
major sources of nitrogen oxides and VOCs. Add sunlight and hot weather to the
mix, and harmful concentrations of ozone may develop. Because of the heat
factor, ground-level ozone is a summertime air pollutant that can be dangerous,
especially for people with respiratory illnesses. Problems include:
- Irritation of the lungs that causes
inflammation much like a sunburn.
- Coughing, wheezing, and pain when
taking a deep breath, and breathing problems while
exercising.
- Permanent lung damage from repeated
exposure.
- Aggravated
asthma, increased susceptibility to
pneumonia and
bronchitis, and reduced lung capacity.
-
Particulates.
Particulates include dust, dirt, soot, smoke, and liquid droplets found in the
air. They come from many sources, such as vehicles, factories, construction
sites, unpaved roads, and burning wood. Other particulates are formed when
gases from burning fuels react with water vapor and sunlight. This can result
from the combustion of fuels in motor vehicles and from industrial and power
plants. Particulates in the air you breathe can cause:
- Aggravated asthma.
- Chronic
bronchitis.
- Coughing
and difficult or painful breathing.
- Reduced lung function.
- Eye, nose, and
throat irritation.
-
Carbon monoxide. In
cities with lots of traffic, most of the carbon monoxide put into the air
comes from vehicle exhaust. It also comes from manufacturing processes, wood
burning, and forest fires. Indoor sources include cigarettes and space heaters.
Carbon monoxide reduces the body's ability to deliver
oxygen to tissues and organs, such as the heart and brain. It is especially
dangerous for people who have heart problems. Carbon monoxide can be fatal to
those exposed to extremely high levels. Every year
carbon monoxide poisoning is a leading cause of
deaths from toxic chemicals. People with carbon monoxide poisoning may have:
-
Nitrogen dioxide. When
mixed with other particles in the air, nitrogen dioxide can often be seen as a
reddish brown layer over many urban areas. Sources are fuels burned by
vehicles, electric utilities, and industrial plants. Nitrogen dioxide is one of
the nitrogen oxides, a group of highly reactive gases that contain various
amounts of nitrogen and oxygen. Nitrogen oxides cause many problems,
including:
- Respiratory problems associated with
ground-level ozone.
- Acid rain, which is made when nitrogen
oxides and sulfur dioxide react with other substances in the air and form
acids. The acids then fall to earth as rain, snow, dry particles, or fog.
- Toxic chemicals. Nitrogen oxides mix with common organic chemicals
and even ozone to create toxic chemicals that can cause biological
mutations.
- Visibility impairment. Nitrogen dioxide and nitrate
particles block light transmission and reduce visibility in urban areas.
-
Sulfur dioxide. These
gases are formed when fuels containing sulfur are burned. Examples are when coal and
oil burn, when gasoline is extracted from oil, or when metals are
extracted from ore. Sulfur dioxide is
put into the air when fossil fuel is burned, such as by coal-fired power plants.
Other sources are industries that create products from metallic ore, coal, and
crude oil or those that burn coal or oil, such as petroleum refineries or metal
processing facilities. Sulfur dioxide causes:
- Health problems for people with asthma
and heart conditions.
- Acid rain.
- Damage to forests and
crops.
- Damage to fish in streams and lakes.
-
Lead. Leaded gasoline
used to be the main source of lead in the air. But because leaded fuels have
been phased out, the main sources of lead emissions are metals-processing
facilities, especially lead smelters. Lead may cause serious health problems,
including:
- Damage to kidneys, liver, brain, nerves,
and other organs. Lead may also cause
osteoporosis and reproductive problems. Excessive
exposure can cause seizures, intellectual disability, behavioral disorders, memory problems, and mood
changes. Low levels of lead cause brain and nerve damage in young children and
fetuses, which can lead to learning problems and low IQ.
- High blood pressure and increases in heart disease.
- Anemia.
For more information, see the topics
Carbon Monoxide Poisoning and
Lead Poisoning.
Pesticides
Exposure to pesticides may come from
residual agricultural pesticides in foods; from household or workplace
products used to control rodents, insects, and termites; and from disinfectants
and fungicides. The most likely ways you are exposed are small quantities of
pesticides in the foods you eat and by direct contact with surfaces (such as
plants, soils, or structures) where pesticides have been used.
If
not used properly, both workplace and household pesticides can be dangerous.
Exposure to high levels of some pesticides can cause headaches, dizziness,
muscle twitching, nausea, weakness, and tingling sensations. Some experts
believe that some pesticides may cause cancer or damage to the liver and
central nervous system.7, 8 Pesticide exposure during
pregnancy has been associated with
miscarriage, fetal death, and early childhood cancers
such as
acute lymphoblastic leukemia (ALL). Indoor use of
pesticides increases children's risk of brain tumors, ALL, and birth defects.
Children can be poisoned by stored pesticides, so these should always be kept
out of reach. For agricultural workers, exposure to pesticides has been
linked with an increased risk of
non-Hodgkin's lymphoma.9
See
tips for reducing pesticide exposure in your home, such as reducing your use
of lawn and garden pesticides and limiting your exposure to moth
repellents.
Mercury in fish
For most people, the level of
mercury absorbed by eating fish and shellfish is not a health concern. But in a
fetus or young child, this can damage the brain and
nerves (nervous system). Because of the mercury found in fish,
the U.S. Food and Drug Administration (FDA) and the U.S. Environmental Protection Agency
(EPA) advise women who may become pregnant, pregnant women, nursing mothers,
and young children to avoid eating fish high in mercury and to eat limited
amounts of fish and shellfish that are lower in mercury.10 For more information, see the topic
Avoiding Mercury in Fish.
Chemicals from plastics and other
products
Some people are concerned about
bisphenol A (BPA). This is a chemical found in some types of plastic (polycarbonate)
bottles. A study has shown that people with high levels of BPA in their urine have a greater risk for heart disease.11 And a group of experts concluded that bisphenol A may have some effect on
the behavior, brain, and prostate gland of a developing baby (fetus) or young child.12, 13 If
you are concerned about BPA, don't use bottles marked with the number 7 or the
letters "PC" near the recycle symbol. You can use glass or BPA-free plastic
bottles instead.
In the past, a group of substances called polychlorinated biphenyls (PCBs) were used in electrical equipment, plastics, and dyes. Although they are no longer made in the U.S., they remain in the environment. Exposure to PCBs has been linked to health problems, especially mental functions such as memory and attention in children.14 The U.S. Environmental Protection Agency (EPA) provides information about PCBs at http://www.epa.gov/epawaste/hazard/tsd/pcbs/index.htm.
Chemicals called phthalates
may cause problems with the reproductive organs of infants and young
children, especially boys. Phthalates can be found in some plastic items (such as some medical
devices) and in products such as powders, lotions, and shampoos.15, 16