It seems a lot of Australian homeowners are turning to carcinogenic herbicides to keep their pools the right shade of blue.

Authorities are considering placing a ban on the use of herbicides which have a key ingredient called simazine which is of particular risk to children.

There are almost 1 million swimming pools in Australia. In a sun-soaked land they provide fun for children and relief from the heat.

Dr Alison Bleaney is a GP in Tasmania and for a long time has had concerns about the use of chemicals in swimming pools.

"The concern is that children are more susceptible to the effects of chemicals in their bodies than adults are, just by the fact that they're smaller, their systems are not capable of detoxifying nasty chemicals the way an adult is," she said.

"We know that the trizines, atrazines, simazines, are immune modifiers, they modify our immune systems, they affect our hormone systems in extremely small levels.