PFAS are chemical compounds considered to be very widely distributed throughout the environment. However, the results from the recent Queensland Ambient Monitoring Program (2019-2020) showed that this is not necessarily the case in QLD, and elevated PFAS were linked to urban areas (Baddiley et al. 2020). The Ambient Program found PFAS concentrations in water were highly variable over a period of twelve months, and that PFAS burdens in biota was a good indicator of the contamination present in the waterway of estuarine environments. As the program had focussed on estuarine systems, an opportunistic study was undertaken in 2021 on fish and other biota from 31 freshwater sites across the urbanised areas of Southeast Queensland (SEQ). Eight of the sites that had some of the highest concentrations of PFOS were selected for a more detailed study.
The potential for PFOS to bioaccumulate in aquatic biota where water concentrations below the Draft ANZG Default Water Quality Guideline Value (DGV) has been acknowledged in the draft PFOS DGV technical brief. The further monitoring at the eight contaminated sites was undertaken to understand the concentrations of PFOS that lead to bioaccumulation in freshwater ecosystems in SEQ. The monitoring consisted of an initial biota survey, sampling of PFAS in water every two months for a year and a final biota survey. Here we present the results of the opportunistic and follow-up monitoring programs and compare the results against the current guidelines for the protection of aquatic ecosystems to assess how well they protect mammalian and avian consumers of aquatic biota from the risks posed by PFOS.