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Analysis of Waikato river water samples for selected endocrine disrupting chemicals and hormonal activity

TR 2013/55
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Report: TR 2013/55

Author: LA Tremblay (Cawthron Institue) and GL Northcott (Northcott Research Consultants Ltd)

About this report

Endocrine disrupting chemicals (EDCs) are a class of contaminants. They are of significant concern, due to their potential to disrupt endocrine functions in wildlife and human populations.  

Two significant sources of EDCs are from urban wastewater treatment plants and dairy farming waste. Potential sources of EDCs to the Waikato River include wasterwater discharge from a number of wastewater treatment plants along its length and the prevalence of intensive dairy farming in the region.


The Waikato Regional Council contracted Cawthron Institute to assess the endocrine disruption potential of eight water samples collected from the Waikato River between Taupo and Tuakau. The concentration of selected EDCs and the total endocrine activity was assessed using trace chemical analysis and bioassay methods.

Read or download the survey report

Analysis of Waikato river water samples for selected endocrine disrupting chemicals and hormonal activity [PDF, 784 KB]