An assessment of endocrine activity in Australian rivers using chemical and in vitro analyses

Studies on endocrine disruption in Australia havemainly focused on wastewater effluents. Limited knowledgeexists regarding the relative contribution of different potentialsources of endocrine active compounds (EACs) to the aquaticenvironment (e.g., pesticide run-off, animal farming operations,urban stormwater, industrial inputs). In this study, 73river sites across mainland Australia were sampled quarterlyfor 1 year. Concentrations of 14 known EACs includingnatural and synthetic hormones and industrial compoundswere quantified by chemical analysis. EACs were detectedin 88 % of samples (250 of 285) with limits of quantification(LOQ) ranging from 0.05 to 20 ng/l. Bisphenol A (BPA; LOQ=20 ng/l) was the most frequently detected EAC (66 %) andits predicted no-effect concentration (PNEC) was exceeded 24times. The most common hormone was estrone, detected in28 % of samples (LOQ=1 ng/l), and the PNEC was alsoexceeded 24 times. 17α-Ethinylestradiol (LOQ=0.05 ng/l)was detected in 10 % of samples at concentrations rangingfrom 0.05 to 0.17 ng/l. It was detected in many sampleswith no wastewater influence, and the PNEC wasexceeded 13 times. In parallel to the chemical analysis,endocrine activity was assessed using a battery ofCALUX bioassays. Estrogenic activity was detected in19 % (53 of 285) of samples (LOQ=0.1 ng/l 17β-estradiol equivalent; EEQ). Seven samples exhibitedestrogenic activity (1–6.5 ng/l EEQ) greater than the PNECfor 17β-estradiol. Anti-progestagenic activity was detected in16 % of samples (LOQ=8 ng/l mifepristone equivalents;MifEQ), but the causative compounds are unknown. Withseveral compounds and endocrine activity exceeding PNECvalues, there is potential risk to the Australian freshwaterecosystems.