Last week the Australian government cancelled the registration of all products containing chlorthal dimethyl, a weedkiller commonly known as dacthal.
No phase out period applies. The cancellation is immediate, due to the risks it poses to human health – primarily unborn babies.
In Australia it is used in twelve herbicide products. All have been cancelled as of October 10 2024.
Dacthal was found to inhibit two thyroid hormones in rat pups whose mother had been exposed while pregnant.
Decreases in these two hormones are associated with risks to unborn children including low birth weight and impaired brain development, IQ and motor skills.
Of particular concern was the effects occurred at much lower levels than previously thought. The decreases in T3 and T4 occurred in rat pups exposed to levels of dacthal ten times lower than the safe threshold for their mothers. This means pregnant rats exposed to dacthal at those levels had no adverse effects, but their unborn babies did.
The changes in regulation are based on the potential harms if unborn babies are exposed via their mothers.
[Ed: And how many other products are yet to be tested on female rats, let alone those that are pregnant?]
Source: An immediate ban has been issued for the herbicide dacthal. What are the health risks?
Where are the warnings because unless in the public arena some supplies may be still being used people tend to have these sorts of things around for years