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In South America, Argentina and Chile are affected. There are also many locations in the United States where the groundwater contains arsenic concentrations in excess of the [[United States Environmental Protection Agency|Environmental Protection Agency]] standard of 10 parts per billion adopted in 2001. According to a recent film funded by the US [[Superfund]], {{cite web |url=http://www.youtube.com/watch?v=hi5DfRy01vE |title=In Small Doses |format= |work= |accessdate=}}, millions of private wells have unknown arsenic levels, and in some areas of the US, over 20% of wells may contain levels that are not safe.