In order to maximize gold extraction, mercury is often used to amalgamate with the metal. The gold is then produced by boiling away the mercury from the amalgam, a process which is hazardous owing to the toxicity of mercury vapor. Mercury is effective in extracting very small gold particles, but should be reclaimed in an effective and safe process. With the price of gold at record levels. the small-scale mining sector, much of it illegal and unregulated, is expanding worldwide faster than at anytime in history and, with it, the health threats posed by mercury. This global gold rush began in Brazil in the late 1970s, before sweeping South America, Asia, and Africa, with an estimated 15 to 20 million prospectors now active in more than 60 countries. Poverty driven miners rely on inexpensive, outdated, polluting technologies and chemicals because it is what they can afford. Mercury can vaporize and exposure to concentrations above o.1 mg/m3 can be harmful. At this level, humans cannot detect the Mercury and can be exposed until harmed.