Lack of employment and income opportunities are pushing large contingents of people to frontier areas and new economic activities, such as gold mining, in the Amazonian region. The number of independent gold miners exceeded 200,000 by 1990. The mining process generates very dangerous and poisonous mercury pollution (mercury is used to separate the gold from other materials), and destroys aquatic and forest habitats. The local population whose diet depends on fish are now threatened by mercury poisoning, as are the miners themselves. –United Nations Research Institute for Social Development Read the text, then use the drop-down menus to complete the statements. People have turned to gold mining because of a lack of opportunities. The is dangerous because it generates mercury .