You don't have to be a scientist to understand arsenic will kill you. Even at low levels, this element can cause cancer, if you ingest it for a long time. Unfortunately, naturally-occurring arsenic has tainted drinking water wells in many countries. In Bangladesh, an estimated 43,000 people die every year from drinking arsenic-laced water in what the World Health Organization describes as the "largest mass poisoning in history."
Closer to home, the desire of two companies to keep selling an arsenic-based weed-killer have apparently stymied the federal government's effort to protect public health. The non-profit Center for Public Integrity reported that a single member of Congress, U.S. Rep. Mike Simpson, R-Idaho, inserted language in a bill that delayed the EPA's plan to impose stricter limits on how much arsenic is allowed in drinking water. CPI's David Heath reported that Simpson had been lobbied by Drexel Chemical and Luxembourg-Pamol, two companies that manufacture a pesticide that would be banned once the EPA rules became final.
It's exactly that kind of political meddling in science that President Obama vowed to stop when he came into office. The CPI report shows how EPA still cannot keep up with industry, which introduces hundreds of new chemicals, with unknown health consequences, every year.
The searchable map of drinking water contamination accompanying the report makes Minnesota look like the arsenic capital of the nation. Yet it's only the result of better data: only Minnesota and Texas provided data for test results of private wells, in addition to community wells. The Minnesota Department of Health's map of arsenic-tainted wells is below: