A mass estimate of perfluoroalkyl substance (PFAS) release from
Australian wastewater treatment plants
Chemosphere 208 (2018) 975e983
C. Gallen a, *, G. Eaglesham a, D. Drage b, T. Hue Nguyen a, J.F. Mueller a
4. Conclusions
PFAS were ubiquitously detected in Australian wastewater and
biosolids samples. At 11 of 14WWTPs, effluent PFAS concentrations
exceeded concentrations in the influent by an average of almost 10
times, a likely result of the degradation of precursor chemicals
during the treatment process. To date, there have been no studies
investigating the identities of PFAS-precursors present in Australian
WWTPs. For three of the nine studied PFAS, only a relatively
small proportion (an average of 1% or less of the total loads discharged
from the participating WWTPs) are removed to the biosolids,
with the majority of the load released in the effluent. As PFAS
chain length increased, the proportion of PFAS loads contained
within the biosolids increased. PFAS concentrations were shown to
vary widely between individual WWTPs, suggesting that WWTPs
may be a useful means to identify PFAS-use ‘hotspots’ as well as
cost effectively assessing changes in PFAS use, human exposure and
environmental release over time. While many known point sources
of PFAS such as airports are under scrutiny and undertaking
remediation, WWTPs remain ongoing and largely unregulated
sources. Despite the successful elimination of most PFOS and PFOA
products from large-scale use, the use of other PFAS-containing
products appears to be continuing in Australia. The resistance to
degradation processes together with typically long service lives of
the products that contain PFAS, means that the management of
PFAS in Australian waste will be ongoing, potentially for decades.