A rapid method for simultaneous determination of arsenic, cadmium and lead in drinking water by inductively coupled plasma mass spectrometry
Joshua Rey P. Torres
Natural Sciences Research Institute, UP Diliman
Ma. Krystell G. Banaag
National Institute of Geological Sciences, UP Diliman
Irene B. Rodriguez
Institute of Chemistry, UP Diliman
The raw water source of drinking water in most areas in the Philippines is typically river water and in some cases groundwater. These sources are prone to elevated levels of metals and metalloids that may cause exposure of the general population when the treatment of the water is inadequate. This work presents a method optimized for the determination of arsenic (As), cadmium (Cd) and lead (Pb) in drinking water using inductively coupled plasma-mass spectrometry (ICP-MS) as the element-selective detector. This was applied in the determination of these elements in the water supply in Metro Manila, Philippines. The method detection limits were 0.095 μg L-1, 0.043 μg L-1, and 0.114 μg L-1 for total As, Cd and Pb, respectively. The method was validated using National Institute of Standards and Technology (NIST) 1643e certified reference material for trace elements in water and determined values were 60.4 ± 0.5 μg L-1, 6.7 ± 0.1 μg L-1, and 19.6 ± 0.5 μg L-1 for As, Cd and Pb, respectively. These determined values were in good agreement with the certified values in the reference material. Analysis of actual drinking water samples showed that most samples did not exceed the limit of the Philippine drinking water standard for the elements.