Trumped by traditional hazards: EDC exposure from recycled wastewater compared to other water related risks in developed and developing nations

Israel is the global leader in wastewater reuse making it the ideal test case to investigate human exposure to contaminants via recycled wastewater pathways. Studies around the world have revealed that wastewater frequently contains endocrine disrupting chemicals (EDCs) that are not completely removed by traditional treatment. As these compounds can harm ecological and human health, it was initially hypothesized that residual EDCs were contributing to reproductive problems in Israel's population. The fate of EDCs from wastewater effluent in Israel and the Palestinian West Bank's shared water basins was assessed over a two year period, and the associated health risks and economic costs of competing wastewater treatment options evaluated. Results from this analysis can inform both developed and developing nations since Israel highly treats and reuses most of its wastewater while only a small percent of sewage undergoes any treatment in the Palestinian territories. EDCs in the region's aquatic environment were measured at concentrations consistent with global averages. According to modeling results, human exposure to bisphenol A via recycled wastewater is likely small compared to ingestion through food. While a potential health risk was identified from bisphenol A in recycled wastewater, it was most pronounced in extreme exposure situations and when reproductive capacity was already compromised. In the West Bank, a costeffectiveness analysis determined that the marginal improvement in removal rates of estrogens from building tertiary versus secondary level wastewater treatment facilities would not justify the added cost to the Palestinian Authority. Secondary treatment of sewage removed EDCs sufficiently, and the money saved by not investing in tertiary treatment could be better used to provide more essential sanitation services. Tertiary treatment produces other important environmental benefits in which countries like Israel may wish to invest, but it yields only marginally better EDC removal, so developed countries aiming to reduce overall EDC exposure should target sources other than treated wastewater. These findings suggest that EDCs from treated wastewater merit continued research, and demonstrate the importance of environmental cooperation in regions with bifurcated development. However, as EDCs are not the biggest risk to human health in developed or developing nations at this time, they should not be the primary driver for policy governing wastewater management.