Free talk and new research into risks of hormone-like chemicals in our waterways

Published 22 March 2004

A free public talk on the environmental and health risks associated with hormone-like chemicals entering our waterways from treated sewerage will be given at Southern Cross University (SCU) this Tuesday, March 23, by an expert on the subject.

Dr Lukas van Zwieten, a scientist from the Wollongbar Agriculture Institute, will speak from 12noon to 1pm on the hazards to marine life and humans associated with a class of compounds known as endocrine disrupting chemicals (or EDCs), which are not removed in the usual treatment of human sewage and animal feedlot effluent.

Dr van Zwieten is also involved a new joint research project at Southern Cross University to investigate whether various ‘ecotechnologies’, such as reed beds and sand filters, are more effective at reducing EDCs than conventional sewage treatment.

He, and Dr Leigh Davison and Dr Keith Bolton from SCU’s Centre for Ecotechnology, will supervise Masters student and chemist from the NSW Department of Agriculture, Tony Tyler, in the two-year project.

“Efforts to purify effluents from domestic and industrial sources have traditionally focused on removal of solids, oxygen-consuming substances, nutrients and toxicants,” Dr van Zwieten said.

“Attention has recently been drawn to a new and ubiquitous class of pollutants, referred to collectively as endocrine disrupting chemicals (EDCs),” he said.

“Among the most common of these are antibiotics, synthetic hormones, many pesticides (including DDT) and some household chemicals. Research indicates that exposure to even minute amounts of these substances can pose a threat to the healthy development of human and other organisms at certain critical stages of their life cycles.

“Disturbingly, conventional wastewater treatment technologies may not be particularly effective at removing these chemicals from effluent streams.”

The chemicals can enter people’s drinking water when a town’s water supply comes from downstream in the same river where treated sewerage is pumped.

These chemicals act like the female oestrogen hormones, and can have a feminising effect on the biota (animal and plant life) in aquatic ecosystems. For instance, male fish become female fish, Dr Davison said.

Developing foetuses in pregnant women could be especially at risk. For example, US research showed daughters of pregnant women given synthetic oestrogen in the 1950s were born with malformed reproductive organs and were infertile.

Dr Davison said the research project would use their pilot-scale reed bed and sand filter systems at the South Lismore Sewage Treatment Plant and at a piggery near Casino.

Dr Lukas van Zwieten’s talk ‘Endocrine Disrupting Chemicals: why are they a problem and how can we detect them?’ will be presented on Tuesday, 23 March, from 12 noon 1pm, in SCU Lecture Hall U 231 (U Block).

For further information contact Dr Leigh Davison, Head of the Centre for Ecotechnology at SCU, Ph: 6620 3847.

Media contact: SCU Media Liaison Sara Crowe Ph: 6620 3144 or Brigid Veale 6659 3006.

PIC CAPTION: L-R Dr Leigh Davison, Director of SCU's Centre for Ecotechnology, and Dr Lukas van Zwieten, from Wollongbar Agriculture Institute.