A Sydney council has agreed to trial a new weed-killer after workers walked off the job in response to safety concerns over using Roundup.
A Sydney council has announced it will trial a new weed killer after more than 500 workers walked off the job due to concerns over the use of the glyphosate-based Roundup, which has been linked to cancer.
The union which represents council workers says outdoor staff at Blacktown City Council last month refused to continue using glyphosate weed killers, including Roundup, due to safety concerns.
The United Services Union claims the "dispute escalated" on Wednesday after management ordered six staff to either use the product or be forced into alternative jobs, resulting in a number of employees stopping work.
Blacktown City Council sought an urgent hearing in the Industrial Relations Commissions on Thursday morning after garbage bins weren't collected and some outdoor services were disrupted due to the industrial action.
In a statement, the council said it was guided by Australia's pesticides authority which states that glyphosate is safe for humans, animals and the environment and notes no regulatory agency in the world considers it to be a carcinogen.
The council on Thursday afternoon announced the commission had endorsed an agreement between it and the union that will see workers return to their jobs so long as the council implements a trial of a "viable alternate weed control product".
The trial will see just one of the council's crews using the alternate product while others continue to use a glyphosate-based product, the council said in a statement.
"Council is continually monitoring the situation and will act according to the recommendations of the regulator and on the findings that result from the trial," Blacktown Mayor Stephen Bali said in a statement.
"We have agreed to trial viable alternatives. What is important for everyone to understand is that council will not place employees or members of the public at risk."
Bayer, which bought Roundup maker Monsanto for $US63 billion ($A90 billion) in 2018, says Roundup's active ingredient glyphosate is safe for human use and not carcinogenic.
But the company faces lawsuits by more than 13,400 plaintiffs in the US and globally and a series of Roundup jury verdicts against Bayer have prompted its share price to plummet.
Among the Australian plaintiffs is Victorian gardener Michael Ogalirolo, 54, who regularly used the herbicide between 1997 and 2018 and has developed non-Hodgkins lymphoma.
Mr Ogalirolo filed a writ in the Victorian Supreme Court in June alleging Monsanto Australia failed to warn its Roundup products were dangerous to human health.