Bulletin #49 - Pesticide in pools far above safe limit     


Pesticide in pools far above safe limit

Matthew Denholm | May 18, 2009

Article from:  The Australian

PESTICIDE regulators will consider banning or restricting the use of a controversial chemical in swimming pool treatments after concerns were raised about potential harmful impacts on children who swim regularly.

Australia's pesticides regulator told The Australian it would review the use of the herbicide simazine, a common ingredient in swimming pool anti-algae treatments and suburban weed killers.

The Australian Pesticides and Veterinary Medicines Authority revealed it would consider imposing restrictions on its use, including in pools, while the review was being conducted.

The action follows concerns raised within the APVMA community consultation committee that children who regularly swam in pools treated with simazine might be receiving doses far exceeding the acceptable daily intake (ADI).

"We could be looking at a scenario where children could be exposed to five or six times the ADI for simazine over several months each year," said Anthony Amis, the committee's environmental representative.

Mr Amis made several calculations, which were presented to the APVMA, based on recommended dosages of popular anti-algae treatments, official figures relating to skin exposure and the rate at which children swallow water while swimming.

"Simazine levels in pools, I worked out, could be as high as 30 parts per billion immediately after the second treatment, meaning that a child of six years of age weighing 20kg would only need 45 minutes of swimming to breach the ADI," Mr Amis said.

"A child of three years weighing 10kg would need only 20 minutes in such a pool to breach the ADI."

The results showed the pool water far exceeded the ADI for simazine of .005 micrograms per kilogram and in some cases was 1.5 times the Australian drinking water guideline health limit.

Research showed children ingested 50ml of pool water per hour of swimming. "If this level of simazine was recorded in a domestic water supply, the public would be outraged ... yet the Australian Government is allowing young children to swim in pools treated at this level (30ppb)," said Mr Amis, a Melbourne-based researcher with Friends of the Earth.

After being alerted to Mr Amis's concerns, the APVMA and federal Agriculture Minister Tony Burke's department confirmed a review of simazine would be conducted later this year.

In a response endorsed by the APVMA, the department's general manager of food and product safety, Richard Souness, said: "The review ... will include the impacts of simazine use in swimming pools and will, therefore, consider public health impacts, such as the impacts on children.

"The scoping exercise (for the review) will also determine whether restrictions should be placed on current uses of simazine, including its use in swimming pools, while the review is being conducted."

Concern over cancer links led to the US banning simazine for use in swimming pools in 1994, but Mr Souness said these concerns were no longer current.

Children exceeding the ADI were unlikely to suffer health impacts, since it was based on a lifetime of exposure, and there was no evidence of "adverse effects".

A separate review is also under way by the Office of Chemical Safety to determine whether triazine herbicides, including simazine, can harm human hormonal systems.

A state-commissioned report revealed that the herbicides remain in the environment for up to three times longer in cool-climate regions.

The report, revealed in The Australian last month, concluded that because of triazine chemicals' longer half-life in cool conditions, ability to leach into soils and widespread use, they represented "the most significant environmental risk for water quality".

            
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