Recalcitrant Pollutants

Recalcitrant pollutants are substances that persist in the environment for long periods of time before being degraded by natural occurring microorganisms, says Professor Joseph W. Lengele in "Biology of the Prokaryotes." These pollutants can last for hundreds of years in the environment, causing wildlife intoxication and soil pollution. Recalcitrant pollutants include DDT (dichloro-diphenyl-trichloroethane), dichloropropane, dibromo-3-chloropropane and polyethylene.

DDT

• DDT is an insecticide first synthesized in 1874. Its use was cancelled in the United States in 1972 due to potential health effects on population and wildlife, reports the National Pesticide Information Center. DDT is highly persistent (recalcitrant) in the environment. The soil half-life for DDT is between two and 15 years. In an aquatic environment, the half-life of DDT can reach 150 years.

Halopropanes

• Halopropanes, such as dichloropropane, trichloropropane and dibromo-3-chloropropane, are chemical substances found in pesticides, paints and varnishes, according to the University of Groningen in the Netherlands. The half-life of dichloropropane ranges from six months to two years. Dibromo-3-chloropropane is no longer manufactured or used agriculturally in the United States due to its high toxicity and half-life of 141 years in water, according to the Office of Environmental Health Hazard Assessment of California.

Polyethylene

• According to the African Journal of Biotechnology, polyethylene is a waxy, translucent and light plastic widely used in industrial and household settings. Many plastic bags are made with polyethylene. If dumped in the environment, a plastic bag can take up to 1,000 years to degrade completely, according to Times Online. Plastic bags can be lethal to wildlife when the animals mistake the bags for food.