Public Health Assessment of potential hazards in private drinking water wells in the industrial park of Casares (Málaga)

Abstract

This study intends to show the applicability of the Public Health Assessment (PHA) methodology used by the Agency for Toxic Substances and Disease Registry (ATSDR, USA), as a public health tool for prioritizing and systematizing the risk management process related to human exposure to chemicals. Specifically, the potential risk factors that could affect the private drinking water wells in the industrial park of Casares (Málaga) (PIC) have been assessed. The PIC is located close to the Urban Solid waste treatment plant of the Costa del Sol and a sealed landfill. Detailed analysis of the geomorphologic characteristics, climatic conditions, and economical activities – present and past- of the area made it possible to identify potential exposure pathways, and the most probable chemical hazards that could affect private drinking water wells in the area. ATSDR’s methodology was complemented by the implementation of models for the assessment of groundwater contamination (SIG Models), and by a search in international databases for chemical identification. As a result of the present study, two different aquifers were identified as suppliers of the 4 private drinking water wells of the PIC, which entailed a differential analysis of potential risk factors. Landfill and livestock activities in the area seem to be the most relevant sources of hazards in the identification of the exposure pathway, whereas agricultural activity could be ruled out. There is need to increase the frequency of quality control procedures and long-term monitoring of the groundwater to characterize possible faecal contamination and the level of exposure to heavy metals (As, Pb, Hg), as well as to volatile organic compounds (tetrachloroethane, and vinyl chloride). The significant levels of total coliforms found in all the wells indicate that possible leachates from neighbouring municipal sewage systems also have to be investigated.