Pollution is the introduction of harmful contaminants into air, water or soil. These contaminants can have dire effects on entire ecosystems, making life more difficult for humans, plants and animals. Children and the elderly are particularly susceptible to the health effects from these toxins. In many cases, exposure to pollution has a cumulative effect on the body (see References 1).
Air pollution consists of solid particles and gases. Many pollutants are carcinogens. People who breathe in these poisons are at a higher risk for asthma and reproductive-system damage. According the the U.S. Environmental Protection Agency, birth defects can also be caused by air pollution. (see References 1) A 1995 study found a link between air pollution and increased deaths from cardiovascular and respiratory problems (see References 2). Humans are not the only living creatures affected by toxic air pollutants. Some toxins, like mercury, settle onto plants and into water sources that are then consumed by animals. The health effects of these poisons are then magnified up the food chain. Animals that are are at the top of the food chain end up with the largest concentrations of toxins in their bodies. (see References 2)
Water is a necessity of life. People and animals need clean drinking water. Farmers need water to irrigate crops. People enjoy using lakes and rivers for recreation. Unfortunately, this precious resource is easily contaminated by agricultural runoff, mining activities, waste treatment plants and improperly disposed-of industrial waste. The U.S. Environmental Protection Agency monitors 80 different contaminants that may affect drinking water. Microbial contaminants include bacteria and viruses. Most people can fight off the microbial contaminants, however, people with compromised immune systems can get dangerously ill. Contaminants like solvents, pesticides, radium and arsenic are more sinister. This type of pollution can cause long-term health problems for people. Wildlife can also die from exposure. (See References 3)
Litter is unsightly and dangerous. It often consists of plastic, metal or glass — materials that do not break down easily in the environment. People, especially children, can be seriously injured by a broken bottle or a rusty piece of discarded metal. Medical and sanitary wastes are biohazards that can make people sick. Litter also destroys the beauty of parks and beaches, making people avoid these areas. Litter is deadly to wildlife, especially marine animals. Street litter washes into storm drains, into our waterways and ultimately ends up in the ocean. Some of this litter washes back up onto beaches. Some stays in the water, where it can kill wildlife. Entanglement causes animals to die slowly. Birds are particularly susceptible to entanglement as they collect material for their nests. A curious animal that ingests litter can die of starvation or malnutrition if the foreign object blocks the animal's intestinal tract. Litter can also smother and damage seabeds. Toxic substances from litter also accumulates in fish, exposing the people and animals further up the food chain to these pollutants.
Soil contamination consists of either liquid or solid particles mixed with soil. The contaminants may be physically attached to the soil particles or they may be in the spaces between the soil particles. Contamination results when hazardous substances are spilled or buried in the soil. It can also occur when pollutants settle on the soil, such as chemicals or waste from an industrial smokestack. Plants grown in contaminated soil take up the hazardous substances through their roots. Humans or animals that ingest these plants may get sick. People and animals can also inhale soil contaminants through dust that is present in the air or absorb these hazardous chemicals through their skin. (See References 4) A 20-year study published in the "American Journal of Epidemiology" found that people exposed to dioxin in soil experienced a higher rate of diabetes as well as cardiovascular and endocrine problems over the course of the study (see References 5).
- U.S. Environmental Protection Agency; About Air Toxics
- "The Lancet"; Particulate Air Pollution and Acute Health Effects; A. Seaton, et al.; January 1995
- U.S. Environmental Protection Agency; What Are the Health Effects of Contaminants in Drinking Water
- U.S. Environmental Protection Agency: Marine Litter — Trash That Kills; November 2001
- U.S. Environmental Protection Agency: Soil Contamination
- "American Journal of Epidemiology, Vol. 153, No. 11"; Health Effects of Dioxin Exposure; Pier Alberto Bertazzi, et al.; 2000
Based in the Midwest, Bethany Wieman has been writing articles about gardening, DIY, finance, travel and sustainability for more than 10 years. She was featured in the book "The Complete Guide to Growing Vegetables, Flowers, and Herbs from Containers." Wieman's professional background is in marketing, working with such brands as Swiss Army, Timberland and Callaway Golf. She holds a Bachelor of Arts in English.
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