Dangerous Water Pollutants

Clean water is one of life's necessities. Without clean water, people cannot thrive. Unfortunately, chemicals, bacteria and viruses may enter the water supply through processes such as rain runoff. Though some water contaminants may not cause imminent danger, other pollutants endanger lives by contributing to illness and a degradation of the food supply.

Chemical Pesticides

• The Food and Agriculture Organization of the United Nations defines pesticides as chemicals used to control insects, fungi, nematodes and rodents. Pesticides are used not only by farmers but also by homeowners and pest control specialists. Unfortunately, many of these chemicals make their way into the water supply. Ingestion of pesticides may cause cancer, birth defects and immune system suppression. Waters polluted with pesticides also influences aquatic animal and human food supply. Animals may die, mutate, develop cancer or fail to reproduce.

Coliform Bacteria

• Coliform bacteria naturally occurs in humans, animals and the environment, according to the Environmental Protection Agency. The EPA measures these bacteria to determine if dangerous forms of bacteria, such as fecal coliform and E. coli, have polluted water. The source of contamination from these dangerous bacteria is human and animal waste.

  E. coli pollutants may cause infections that exhibit symptoms of diarrhea, stomach cramps and nausea. These symptoms may be more dangerous or deadly in at-risk populations such as the very young, the elderly and those with depressed immune systems. Other microbes that pollute the water supply include Legionella, Cryptosporidium and Giardia lamblia.

Viruses

• The EPA currently regulates enteroviruses that may enter the drinking water supply. Enteroviruses are viruses such as polioviruses, coxsackieviruses and echoviruses that live in an infected human or animal's intestine. These life-threatening viruses may cause everything from a minor stomachache to meningitis in humans. Viruses typically pollute water supply through fecal contamination.

Nutrient Pollution

• Though extra nutrients in the water supply may sound advantageous, nutrients such as nitrogen and phosphorous may contribute to the proliferation of algae and seagrass.

  Excess algae and seagrass mean less oxygen in the water. This results in the death of animals that depend on that oxygen: including fish, shrimp and crabs. Factories and sewage treatment plants are examples of facilities that contribute directly to nutrient pollution. Indirectly, the rain runoff from fertilizers, septic tanks and other material rich in nitrogen and phosphorous contribute to pollution.