Toxins 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.
One of the most common and toxic indoor air pollutants is
cigarette smoke. Experts believe more than 87% of lung cancers are caused by
cigarette smoke.2 Smoking, or even inhaling
secondhand smoke, increases your risk of
heart attack and
stroke.3
Tobacco smoke is a mixture of more than 4,700 compounds. Smoke
from the smoldering end of a cigarette contains more cancer-causing chemicals
than the smoke exhaled by a smoker.4 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 hospitalization, especially when
they develop in babies and young children.5
Babies who are exposed to secondhand smoke are at increased risk
for
sudden infant death syndrome (SIDS).6
Cigarette smoke may cause thousands of children each year to
develop asthma.6 Also, children with asthma who are
exposed to cigarette smoke have more attacks and more severe symptoms than
other children with asthma.6
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 gases, including
carbon monoxide, nitrogen, particulates, 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 doors fit tightly. Only use
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.
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, copy machines, 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, in contrast, 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, molds, and viruses 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 in large heating
and cooling systems in buildings, but they can also be found in home systems
and humidifiers. Legionella pneumophila is an indoor
bacterium that can cause
Legionnaires' disease.
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.
Although studies so far have been inconclusive, evidence is
accumulating that exposure to indoor allergens such as molds early in life can
result in a persistent allergic reaction.7Allergies to molds can also make asthma attacks worse
or cause asthmalike symptoms.
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. Similarly, 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 environment 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 wetted 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:
Controlling indoor allergens.
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 using cleaning or other products, make sure to
open windows or use an exhaust fan to provide good ventilation. Never mix
household chemicals, such as chlorine 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
inside garages. Also, try to limit your exposure to newly dry-cleaned clothing
or furnishings. Dry-cleaned goods emit perchloroethylene (also known as
tetrachloroethylene) and trichloroethylene. These chemicals cause skin rashes,
headaches, and dizziness8, 9 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 is an insulating material commonly used from the 1950s
to 1970s for soundproofing and to cover floors and ceilings, water pipes, and
heating ducts. If it is in good condition, it's generally not a health risk,
but 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 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 arise when concentrations of radon
build 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 12 times higher for
smokers than nonsmokers.10
You cannot smell or see radon, but it's easy to test for 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. Treatment can be as simple as removing and
limiting your exposure to
toxins 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 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 protective layer 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 wood burning. 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.
- Coughing
and difficult or painful breathing.
- Chronic
bronchitis.
- Decreased lung function.
- Eye, nose, and
throat irritation.
- Carbon monoxide. In
cities with lots of traffic, most of the carbon monoxide released 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
toxin-related deaths. People with carbon monoxide poisoning may develop:
- 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 several problems,
including:
- Respiratory problems associated with
ground-level ozone.
- Acid rain, which is created 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 coal and
oil burning, the process of extracting gasoline from oil, or when metals are
extracted from ore. Each year more than 13 million tons of sulfur dioxide are
emitted into the air by electric utilities, especially those that burn coal.
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, mental retardation, 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 or 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.11 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
associated with an increased risk of
non-Hodgkin's lymphoma.12
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 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.13 For more information, see the topic
Avoiding Mercury in Fish.