Laborer heating aqua regia -- a mixture of 5% pure nitric acid and 75% pure hydrochloric acid -- a mixture that will dissolve gold. Without any resiratory protection workers inhale acid fumes, chlorine and sulphur dioxide gas all day as they swirl computer chips removed from circuit boards in acid to collect tiny amounts of gold. The sludges from the process are dumped directly into the river. Guiyu, China. December 2001. Copyright Basel Action Network.