Six other cities in Russia, Kazakhstan, and Kyrgyzstan made the "Dirty 30" list by the New York-based Blacksmith Institute, an independent environmental group.
The authors of the lists say these sites are putting millions of people at risk. They say simple engineering projects could make many of the places safe, but that money and political will are often lacking
One of the top 10 is Dzerzhinsk, a significant center of Russian chemical manufacturing for decades, including chemical weapons. According to official figures, almost 300,000 tons of chemical waste were improperly disposed of in and around the western Russian city until 1998.
The Blacksmith institute says drinking water supplies in the city of Nizhny Novgorod and adjoining villages are now heavily contaminated with pollutants because of the pollution at Dzerzhinsk.
Scant Clean-up
The institute's Meredith Block tells RFE/RL that a number of other sites across the former Soviet Union pose similar threats to human health. "These are places where you had a lot of industrial activities but no regulations," she says. "The proper technology had not been implemented at the time these factories were running and since a lot of them have been closed down and operations have ceased there has been little effort made to actually clean up the legacy contamination left over in these sites."
Blacksmith's top 10 list also includes the Siberian city of Norilsk, which hosts the largest heavy-metal smelting complex in the world; Ukraine's Chornobyl nuclear power plant, where the world's worst nuclear disaster took place in 1986; and Azerbaijan's industrial center of Sumgayit.
Two cities in both India and China, as well as one each in Peru and Zambia, complete the top 10 list.
The 'Dirty 30'
Another feature of the institute's annual report is the "Dirty 30," a more comprehensive group of polluted locations.
Ust-Kamenogorsk (Ost Kamensk in Russian), the capital of Kazakhstan's East Kazakhstan region, is one of them.
The report says extensive industrial operations for over 50 years under poor environmental standards have led to widespread pollution and hazardous waste deposits.
Zhalipbai Dostai, a professor of geography and an environmental activist in Almaty, tells RFE/RL that air pollution remains at a very high level, although industrial production has been somewhat reduced in Ust-Kamenogorsk in recent years.
"Nonferrous metals, ferrous metals, all those industries are concentrated in Ost-Kamensk," he says. "It affects the air, soil, water. The air is contaminated with heavy metals and other sorts of metals. The major problem is the concentration of industrial facilities."In neighboring Kyrgyzstan, the town of Maily-Suu in the Jalal-Abad region was home to a former Soviet uranium-ore mining and processing complex. What remains now are nearly 2 million cubic meters of radioactive mining waste.
A synthetics plant in Sumgayit (Turan)