World's 10 Worst Toxic Pollution Problems [Slide Show]
Mercury, lead, chromium and other toxic compounds, used in many industrial processes, rob years of healthy life from millions each year. Simple fixes could go far in solving the issue
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World's 10 Worst Toxic Pollution Problems [Slide Show]
- ARSENIC AND WELL WATER: The world's worst toxic problems are not confined solely to industrial pursuits. Arsenic leaching into groundwater afflicts some 750,000 people, largely in south Asia. Here a child in Nepal drinks from a well containing water contaminated with arsenic, which can lead to abnormal heart beat, blood vessel damage and cancer, among other ill effects. Courtesy of the Blacksmith Institute
- LEAD–ACID BATTERIES: These rechargeable batteries that help start most cars and trucks are composed of lead plates and sulfuric acid in a plastic case. Used batteries can be easily and cheaply recycled—but are also classified as "toxic waste" by the Basel Convention on hazardous waste and its disposal. The lead plates collect a layer of very fine lead oxide that is often simply shaken off, freeing it to be inhaled or otherwise absorbed into the body. Here a boy melts the recovered lead from a battery in an open container. Courtesy of the Blacksmith Institute
- CARCINOGENIC CHROMIUM: Turning hides into leather in much of the world requires chromium, which in its hexavalent chemical form is a potent carcinogen. Clusters of such tanneries in countries such as Bangladesh produce vast quantities of toxic waste—200 separate tanneries in Hazaribagh combine to produce daily 7.7 million liters of wastewater and 88 million tons of solid waste, like the chromium sludge pictured here. Courtesy of the Blacksmith Institute
- PESTICIDE PROBLEM: Modern agriculture relies on pesticides, requiring the application of some two million metric tons annually on fields. Health effects in humans range from skin irritation, like that pictured here, to cancer. In addition, stockpiles of old, outdated pesticides such as DDT linger. An estimated six to nine million metric tons of such pesticides persist, often improperly stored. Illiteracy compounds the problem. "Even if we put some information on the pesticide containers themselves, [most users] will not understand," says physicist Stephan Robinson of Green Cross Switzerland. "Container management in pesticides is very important. Give to a farmer a new container of pesticides only if he gives you back the empty container," so he cannot use it for food storage. Courtesy of the Blacksmith Institute
- INDUSTRIAL WASTEWATER: Concentrating wastewater in industrial parks allows for shared environmental controls—except, too often, such technology is not employed, like the wastewater from an industrial park flowing in an open drain (pictured). Lead from battery manufacture, smelting, leaded glass production as well as from pigments, paints, ceramics, glazes and e-waste all too often ends up in the environment as a result, where it causes development disorders in children, among other harmful health effects. For example, the Malir River in Karachi, Pakistan, boasts lead levels of 2,170 parts per billion, or 100 times higher than the health standard for irrigation water. Courtesy of the Blacksmith Institute
- ELEMENTAL MERCURY: The "quicksilver" pictured here in a miner's hand is used to bond to gold in a slurry. The gold–mercury amalgam is then heated, usually in the open air, exposing miners, their children and the world to vaporized mercury—a potent neurotoxic element that causes developmental disorders and affects the central nervous system. Courtesy of the Blacksmith Institute
