1 January 2004 Problem Chemicals in the Australian and New Zealand Environment

Over recent decades scientists have become increasingly aware that some man-made chemicals released into the environment that at first appear safe can, in fact, have negative effects on people and wildlife via hitherto unknown biological mechanisms.

Fred Leusch, a PhD student in the Animal and Food Sciences Division at Lincoln University, is studying the effects these chemicals (called endocrine disrupters – EDCs) may be having on the New Zealand and Australian environments.

EDCs can come from a range of industrial, agricultural and municipal sources and include chemicals like certain pesticides, surfactants, active ingredients of the contraceptive pill, and components used in packaging.

Increasing urbanisation and the use of these chemicals could result in EDCs accumulating in waterways.

Mr Leusch said he hoped to provide a clearer picture of the current situation and find out whether there are EDCs in local sewage water or not.

“Several studies overseas have reported that fish living downstream of sewage treatment outfalls can exhibit significant sexual abnormalities (such as feminisation of male fish and decreased fertility), which have been linked to EDCs in treated sewage water.

“My preliminary results showed that there is both good and bad news for Australia and New Zealand,” said Mr Leusch.

“The bad news is that untreated wastewater does contain EDCs at levels that could affect wildlife. The good news is that almost all seem to be removed by secondary wastewater treatment, so that the final secondary-treated effluent is, generally, clean of EDCs.”

Dr Louis Tremblay of Landcare Research, Lincoln, who is co-supervisor of Mr Leusch’s research, said that it is important that these sorts of studies are carried out in this part of the world.

“As the world’s population and its wastes increase scientists need to continue to develop new methods to ensure that the environment is kept free from compounds in sewage and waste water that could harm either wildlife or humans,” he said.

Mr Leusch is carrying out his work in conjunction with staff from Manaaki Whenua Landcare Research NZ Ltd, CENTOX and Griffith University in Australia.

Janette Busch, Technical Writer, Lincoln University, Canterbury, New Zealand