The five worst environmental threats to children's health.

According to a 1997 report from the Natural Resources Defense Council (NRDC), growing evidence points to a link between pollution and childhood illnesses. In the last 50 years, more than 75,000 chemicals have been developed and introduced into the environment. The overall incidence of childhood cancer increased 10 percent between 1973 and 1994. In the 1980s, asthma rates tripled. While the NRDC report does not establish a direct link between exposure to chemicals and the increase in children's illnesses, it does point out growing scientific evidence of such a link.

The five worst environmental threats to children's health are

* lead,

* air pollution,

* pesticides,

* environmental tobacco smoke, and

* drinking-water contamination.

In the United States, these five threats affect more children than any others.

Children are at greater risk from these exposures than are adults. Because children breathe more air, drink more water, and consume more food relative to their body weight than do adults, they receive higher doses of contaminants present in air, food, and water. Also, children are more susceptible because of the immaturity of their biochemical and physiological functions. Organs that are not fully developed are vulnerable to injury.

Lead

Though banned from gasoline and paint, lead remains a significant risk to children. Lead affects virtually every system in the body and is particularly harmful to the developing brain and nervous systems of fetuses and young children. Exposure to low levels of lead can decrease IQ, cause reading and learning disabilities, reduce attention span, and cause behavioral problems. These effects persist until adulthood and may be irreversible. The primary sources of exposure are lead in old paint in homes, lead in dusts and soil from paint chips, industrial emissions, and lead in drinking water from pipes. In the United States, 900,000 children under six years of age are estimated to have blood lead levels higher than the "level of concern" set by the Centers for Disease Control and Prevention. Lead poisoning, however, is entirely preventable. Parents can have their children tested for lead poisoning by a physician and have their homes evaluated for lead-based paint and plumbing hazards. During repainting or remodeling projects, care should be taken not to create lead dust.

Air Pollution

Common air pollutants such as ozone, particulate matter, nitrogen oxides, and sulfur dioxides are associated with increased respiratory illnesses and symptoms, aggravation of asthma, and decreases in lung function in children. One recent study found an association between particulate air pollution and an increased risk of infant mortality. In 1995, about 18 million children under 10 years of age lived in areas with air quality that did not meet federal standards. The major sources of air pollution include motor vehicles; consumer products; and stationary point sources such as coal-burning power plants, refineries, industrial facilities, incinerators, and metal smelters.

Pesticides

Pesticides have been associated with the development of certain cancers in children, including leukemia, sarcomas, and brain tumors. Many classes of pesticides have been shown to adversely affect the developing nervous system of experimental animals. Parental exposure to pesticides has been linked with birth defects in children. New studies suggest that pesticides may compromise the immune system of infants and children. Children are exposed to pesticides at home, at school, in playgrounds and parks, in food, and in water. The U.S. Department of Agriculture recently found pesticides in 65 percent of nearly 7,000 fruit and vegetable samples tested (65 different pesticides were detected). Eighty-five percent of households stored at least one pesticide, and 47 percent of homes with children under five years of age store pesticides within reach of the children.

Environmental Tobacco Smoke

Environmental tobacco smoke (ETS) contains more than 40 substances that are known to cause cancer in human beings or animals. Annually, ETS is responsible for an estimated 150,000 to 300,000 lower-respiratory tract infections such as pneumonia and bronchitis in children under 18 months of age, resulting in 7,500 to 15,000 hospitalizations each year. ETS worsens asthma in 200,000 to one million children each year. ETS also has been found to induce asthma in children and to increase the risk of sudden infant death syndrome. Forty percent of children under 11 years of age live in homes with at least one smoker. Eight million children under five years of age are exposed to cigarette smoke in the home, and more than one million children become regular smokers themselves each year.

Drinking-Water Contamination

Between 1994 and 1995, 45 million Americans drank water from systems that fell short of the standards set by the Safe Drinking Water Act. Children are at particular risk from drinking-water contaminants, not only because they consume two and a half times more water than adults relative to their body weight, but also because federal standards for pollutants are based on anticipated effects on adults. Many americans consume tap water containing microorganisms, trihalomethanes, arsenic, radon, lead, and pesticides. The quality of bottled water is not necessarily any better.

Children of Color

As a group, children of color are at greatest risk from environmental threats. More African-American and Hispanic children than white children have unacceptable levels of lead in their blood. More African-American and Hispanic children suffer from asthma and are therefore especially vulnerable to the effects of air pollution. Children of farm workers are more likely to be exposed to pesticides because they may accompany their parents to work in the fields and live in housing exposed to pesticide drift from nearby fields.

Recommendations

Steps that parents can take to reduce their children's exposure to environmental toxins include

* testing drinking water,

* running water for 30 seconds when a faucet has been unused for several hours (to reduce lead exposure),

* checking air pollution levels and limiting children's outdoor exercise when smog levels are high,

* buying organically grown food,

* eliminating the use of pesticides around the home,

* working with school boards to reduce use of pesticides around schools, and

* avoiding smoking and smokers.

Also, measures can be undertaken at all levels of government ranging from the federal to the community. The most effective ways to decrease children's exposure are to

* set quantifiable exposure reduction targets and measure progress toward these goals;

* increase the public's right to know about children's exposure to environmental hazards, thereby giving manufacturers an incentive to develop safer products;

* revise existing federal regulatory standards (and state regulations where applicable) to adequately reflect children's differential exposure and susceptibility;

* improve risk assessment to take into account children's unique vulnerabilities;

* expand scientific research on children's environmental health; and

* evaluate community efforts to protect children from environmental threats.

Other Hazards

In the last 50 years, more than 75,000 new chemicals have been introduced into the environment. Besides the five worst environmental threats discussed above, there are other hazards - such as the accumulation of PCBs in fish. Evidence also is emerging about newly identified threats (e.g., endocrine disrupters, which alter hormone functions).

(Source: "Our Children at Risk," National Resources Defense Council, World Wide Web. For a web site address, see the Environmental Health-'Net section on page 48.)