Analysis of Inorganic Arsenic (As(III) and Total As) and Some Physicochemical Parameters in Groundwater Samples from Selected Areas in Bulacan, Batangas, and Laguna, Philippines
Numerous cases of arsenic (As) poisoning from contaminated groundwater have been reported worldwide including the Philippines. The maximum contamination limit has been set by World Health Organization (WHO) for arsenic in drinking water at 10 ppb. This study determined the As(III) and total As content of groundwater samples in selected sites of Bulacan, Batangas, and Laguna by differential pulse anodic stripping voltammetry (DPASV). The pH, temperature, conductivity, total solids, turbidity,
... salinity of the groundwater samples were also determined during sample collection. Groundwater samples from Laguna were naturally warm, with collection temperatures exceeding 30 oC, compared to water samples from Batangas and Bulacan ((T = 27 to 29.5 ˚C). The pH and turbidity of all samples were found to comply with the limits based on acceptability set by the WHO and the Philippine National Standards for Drinking Water (PNSDW). However, some samples had total dissolved solids and salinity beyond the limits set by the WHO and PNSDW guidelines. Moreover, some of the samples tested contained arsenite As(III), the more toxic form of arsenic, above 10 ppb whereas only one water sample tested had less than 10 ppb total arsenic content.