This Top Ten list was compiled by the Technical Advisory Board of the Blacksmith Institute, an environmental NGO based in New York. The criteria used in ranking the include the size of the affected population, the severity of the toxins involved, and reliable evidence of health problems associated with the pollution.
Forty factories that manufacture industrial and agricultural chemicals release 70-120,000 tons of detergents and pesticides into the air every year. Untreated sewage and mercury-contaminated sludge are dumped arbitrarily.
Severe air and water pollution from the coal, steel, and tar industries.
One of the largest lead production bases in China with average lead concentrations in the air and soils 8.5 to 10 times national health standards.
Twelve chromite ore mines dump untreated water into the river, and over 30 million tons of waste rock have been dumped in the valley's riverbanks, which has resulted in severe water contamination.
There are over 1,00 industries covering over a thousand acres in the region that has contaminated local produce.
La Oroya, Peru
Lead, copper, zinc, and sulfur dioxide from mining have contaminative the town.
A major Russian chemical manufacturing center, which produced Sarin and other deadly poisons during the cold war. Between 1930-1998, nearly 300,000 tons of chemical waste were improperly disposed of.
An industrial city in Siberia founded in 1935 as a slave labor camp, Norilsk is home of the world's largest heavy metals smelting complex and is plagued by severe air pollution.
The world's worst nuclear disaster took place on April 26, 1986. The 19-mile exclusion zone around the plant remains uninhabitable.
The country's second largest city is severely contaminated with lead from the mining industry.