The World's Worst Pollution Problems, 2011

Updated February 12, 2020 | Infoplease Staff

According to the Blacksmith Institute, "this report gives an overview of the range of pollution threats humans face throughout the world." Each problem listed below exists in more than one location around the world, so they are truly global issues.

  1. Artisanal Gold Mining: Mercury Pollution
    Artisanal mining uses rudimentary methods to extract and process minerals and metals on a small scale. Artisanal miners frequently use toxic materials, including mercury, in their attempts to recover metals and gems. These toxic materials can be released into the environment, posing large health risks to the miners, their families and surrounding communities. Estimated world population at risk: 3,506,600.
  2. Industrial Estates: Lead Pollution
    Industrial Estates are planned, zoned areas that are set aside for a variety of industries, offices, and production.Unfortunately, in many low- and middle-income countries, industrial estates have little to no waste
    treatment and disposal infrastructure, and they are often located near populated areas. In the case of an industrial estate that has no pollution control mechanisms, lead, which is often a main contaminant caused by industrial estates, can be released into surrounding air, soil, water, and food. Estimated world population at risk: 2,981,200.
  3. Agricultural Production: Pesticide Pollution
    A major factor in agriculture over the last decades is the use of pesticides that protect crops from insects and pests that may be harmful to crop quality and yields. Many chemical pesticides, particularly those containing chlorinated compounds, are often persistent in the environment and can be toxic to humans. Estimated world population at risk: 2,245,000.
  4. Lead Smelting: Lead Pollution
    Lead processing and smelting plants work with both primary and secondary lead. Primary lead is mined, separated from ore, and refined into various products, whereas secondary lead is recovered from used objects - such as used lead-acid batteries - for reuse in other products. Smelting is a key process in lead product production, and involves heating lead
    ore or recovered lead with chemical reducing agents. Both secondary and primary smelting processes can be responsible for releasing large amounts of lead contamination into the surrounding environment. Estimated world population at risk:1,988,800.
  5. Tannery Operations: Chromium Pollution
    The processing of leather creates not only potentially toxic wastewater, but also large amounts of solid waste that contain chromium such as: hide scraps, skins, and excess fats. Toxins from this waste can leach into nearby soil and water, placing nearby residents at risk of contamination. Estimated world population at risk:1,848,100.
  6. Mining and Ore Processing: Mercury Pollution
    Elemental mercury occurs naturally in the earth and is a liquid metal. Most mercury forms in a sulfide ore called cinnabar. Separating mercury from cinnabar can release mercury vapor, which is highly toxic, into the atmosphere. Waste rock and tailings from mercury mining, and other extraction processes where mercury is uncovered, can still contain small or large amounts of the toxic substance. Mercury that is not processed or claimed during mining and ore processing can make its way into the environment if the mining waste is not stored properly. Estimated world population at risk:1,591,700.
  7. Mining and Ore Processing: Lead Pollution
    Mining can be an extremely destructive practice that often has very negative impacts on the surrounding environment. Because the material that is mined for is surrounded by other ore and rock, mining creates large amounts of mineral waste in the form of waste rock and tailings containing lead which can contaminate water and soil. Estimated world population at risk:1,239,500.
  8. Lead-Acid Battery Recycling: Lead Pollution
    The most common example of a lead acid battery is a car battery. When these batteries can no longer hold a charge, they have to be disposed of, but scavenging them and opening them up to extract the lead has become a cottage industry in the developing world. The lead is valuable, but it also puts everyone near it at severe risk for lead poisoning. Estimated world population at risk: 967,800.
  9. Naturally Occurring Arsenic in Ground Water: Arsenic Pollution
    Arsenic is known to be a dangerous toxin that can lead to death when large amounts are ingested. Small amounts of arsenic exposure over long periods of time can also lead to numerous health problems, including abnormal heart beat, damage to blood vessels and a decrease of red and white blood cells, nausea and vomiting, and clearly visible irritations
    of the skin. Estimated world population at risk: 750,700.
  10. Pesticide Manufacturing and Storage: Pesticide Pollution
    Pesticides are widely used in agricultural processes throughout the world in order to protect crops from pests, fungus, and bacteria, but many of these materials have been found to pose such a health hazard that they have been banned. However, many of these products continue to be produced, used, and stored. Some of the more noxious, banned pesticides that can still be found in high quantities in storage facilities are carbamates, persistent organic pollutants, organophosphates, and organochlorines—which include DDT and chlordane. Estimated world population at risk: 735,400.
Source: the Blacksmith Institute, 2011. Web:

Sources +