From Ecos magazine, 6 November 2013:
Every day, Australians flush relatively small – but significant – amounts of chemicals down the drain, many excreted from their own bodies.
These micropollutants – from the diverse medicines, personal hygiene products, household cleaning agents, dietary supplements and other chemical products we now use routinely – make their way to wastewater treatment plants. From there, most are released into our waterways, with potentially devastating consequences for the aquatic fauna exposed to them.
‘Micropollutants is a term which is commonly used for contaminants that occur in the environment at very low concentrations, so here we are talking about micrograms per litre, or even nanograms per litre of water,’ said environmental chemist Dr Rai Kookana, senior principal research scientist at CSIRO Land and Water.
‘The interesting thing is that even at these low concentrations, they have the potential to impact on the health and wellbeing of the exposed organisms.’
The most well-known class of micropollutants is the endocrine-disrupting chemicals (EDCs). These either mimic hormones or interact with receptors for those hormones. The resultant effects include intersex conditions, such as male fish developing female reproductive organs, or producing egg yolk proteins normally only found in females; and changes in reproductive behaviour.
The most notorious of the endocrine disrupting chemicals is DDT. It was first used as a pesticide from the 1930s but was eventually banned from agricultural use after it was found to affect, among other things, female reproductive tract development.
However, DDT was just the tip of the iceberg. Other endocrine-disrupting chemicals are still in widespread use, such as bisphenol A, found in plastics; and polybrominated diphenyl ethers, flame retardants used in the plastic cases of electronic equipment. Read more.