Many environmental toxics have made their way into the environment through industrial processes or human carelessness. Of the more than 77,000 chemicals produced in North America, many are now found in water, air, and even food, with a variety of harmful effects.
A 2009 study detected mercury contamination in 291 streams across the U.S., with over two-thirds of the fish sampled exceeding the U.S. EPA level of concern for fish-eating mammals (U.S. Department of the Interior). The mercury primarily comes from coal-fired power plants and other industrial sites as air pollution; it is then deposited into watersheds through rain or snow.
More than just an environmental issue, environmental toxins are also a public health issue. Mercury, for example, affects brain development, and can cause cerebral palsy, convulsions, visual problems and abnormal reflexes in human fetuses. Most Americans have over 100 different industrial chemicals in their bodies, many of which can cause long-term health effects even at low doses of exposure (Cone). Short- and long-term effects of environmental toxics include cancer, neurological disorders, reproductive disorders, allergies, fatigue, and headaches.
The toxins most prevalent in our air, water, and food include the following (NativeVillage.org):
PCBs (polychlorinated biphenyls) — carcinogenic industrial chemicals. While they are now banned in the U.S., PCBs are very persistent and still present in the environment.
Pesticides — a majority of which are known to be carcinogenic. Pesticide residues have been detected in 50 to 95 percent of U.S. foods.
Phthalates — bisphenyl-A (BPA) being one — which cause endocrine system damage. They can leach into food from plastic wrap, plastic bottles, and other containers.
Dioxins — which are formed by burning waste and fuels. They can cause cancer and a number of other health risks.
Heavy metals — like arsenic, mercury, lead, aluminum, and cadmium — which accumulate in soft tissues of the body. They lead to a wide range of serious health issues, including brain damage, immune suppression, and infertility.
Chlorine — which can cause a number of health problems.
Use of toxic materials on campus is a serious concern in schooling for sustainability. Twenty-five percent of the cleaning products used in schools are toxic. An average custodian uses 23 gallons of cleaning products a year. Custodians and teachers experience some of the highest rates of occupational asthma. Of the 48 pesticides most commonly used on campuses, the EPA classifies 22 as possible or probable carcinogens.
A sustainable society protects its most vulnerable members. Schools with the most health problems are often in the poorest neighborhoods, making reduction of toxics on campus a matter of environmental justice.
References cited in this article may be found in "References" in the Resources page of our website.