this woman runs a shop in sulawesi, indonesia. she says that customers come day and night for the mercury she supplies. >> in one week we sell one tank, each tank is 34 kilos. so in a month we can sell more than 120 kilos. >> reporter: five years ago she started selling mercury illegally. she was arrested but not jailed. instead, the police put her in touch with a legal supplier. they now do business together. it's an example of how the local authorities are complicit in this deadly trade. >> ( translated ): this was made in spain, previously there was some from america. >> reporter: when asked about mercury's health affects on her community, she shrugs. >> ( translated ): what can i do? i'm here to make a living also. we need it others need it which means all of us here need each other. mercury supports this chain. >> reporter: the end of that chain is often china or india. some of it ends up in local markets, like this gold shop in borneo. gold from artisinal mines makes up only ten to fifteen percent of the four ton global gold