Contamination by arsenic and other trace elements in tube-well water and its risk assessment to humans in Hanoi, Vietnam
Concentrations of As and other trace elements and their association were examined in groundwater (n=25) and human hair (n=59) collected at Gia Lam District and Thanh Tri District, suburban areas of Hanoi, Vietnam, in September 2001. Concentrations of As in the groundwater ranged from < 0.10 to 330 mu g/l, with about 40% of these exceeding WHO drinking water guideline of 10 mu g/l. Also, 76% and 12% of groundwater samples had higher concentrations of Mn and Ba than WHO drinking water guidelines, respectively. Arsenic concentrations in hair of residents in Gia Lam and Thanh Tri Districts (range 0.088-2.77 mu g/g dry wt.) were lower than those in other As-contaminated areas of the world, but were higher than those of people in noncontaminated areas. Concentrations of As and Mn in hair of some individuals from the Gia Lam and Thanh Tri Districts exceeded the level associated with their toxicity and, therefore, a potential health risk of As and Mn is a concern for the peop...