Arsenic levels can be "standard" or "safe".
Stöhrer
G
G
D001151:Arsenic / Q000032:analysis* / Q000633:toxicity*; D020261:Arsenic Poisoning; D002295:Carcinoma, Transitional Cell / Q000139:chemically induced / Q000209:etiology; D004326:Drinking; D006801:Humans; D015203:Reproducibility of Results; D018570:Risk Assessment; D014481:United States; D014571:Urologic Neoplasms / Q000139:chemically induced / Q000209:etiology; D014867:Water / Q000737:chemistry / Q000592:standards; D014881:Water Supply / Q000592:standards*
D014867:Water; D001151:Arsenic