Chemical Risk Assessment in the Potable Water Reclamation System in Beaufort West, South Africa Identified contaminants of emerging concern affecting human health

Water reclamation can be one of the solutions when trying to solve the global water shortage. In the dry region Beaufort West, South Africa is a water reclamation plant supplying the inhabitants with drinking water, treated from wastewater. It is, however, important to evaluate the risks connected to this technology. The aim of this study was to conduct a chemical risk assessment in order to identify the potential risks in the Beaufort West water reclamation system that may lead to adverse human health effects from identified contaminants of emerging concern, and to suggest countermeasures to reduce the most severe risks. After identifying probabilities and consequences for the hazards and contaminants through interviews and sampling, a risk matrix was established and two increased risks identified. Both the risks were related to a high exposure of the hormone EE2, commonly used in contraceptives. One risk was connected to a long-term consumption of the final water and the other to unintentional ingestion during children’s prohibited bathing in a brine channel. No increased risks related to EE2 in case of possible technical failures were found. Neither was any risk connected to any other of the analysed contaminants found. Possible countermeasures were suggested to decrease the risks of exposure from EE2 and by performing a Multi-Criteria Decision Analysis was a Granulated Activated Carbon process recommended to be implemented. This study has shown that the Beaufort West direct potable water reclamation system results in very low risks of exposure from a large number of chemical contaminants. However, more research about hormones, degradation products and possible treatment technologies are needed. Further risk assessments should also be performed in this water reclamation system that include more contaminants as well as microbiological risks.