It also cited a 2018 study by the independent National Cancer Institute that followed over 50,000 pesticide applicators for more than 20 years and found no association between glyphosate-based herbicides and cancer.
But the group Gene Ethics said the US case was a"litmus test"for thousands of other US plaintiffs with similar cancer claims.
Roundup products and their active ingredient,glyphosate,have been used safely and successfully for over four decades worldwide.
Bayer
Gene Ethics director Bob Phelps said the amount of glyphosate-based herbicides sprayed in Australia had exploded.
"Warnings are rarely given when Roundup is sprayed in public places and workers usually wear minimal personal protective gear,assuming the product is as safe as Monsanto and Bayer claim,"he said.
The Australian-listed agribusiness Nufarm launched a strong defence of glyphosate on Tuesday,a challenging day for the company that saw its stock price plummet 23.9 per cent to $4.23,wiping more than half a billion dollars off its market capitalisation.
The stock price slumped after Nufarm released a half year result that disappointed investors,cut its earnings guidance and outlined challenges in the second half of the financial year. But the the US legal development concerning glyphosate could also have been a factor in the stock sell-off.
While Nufarm does not manufacture glyphosate,it buys it from manufacturers and uses it as the active ingredient in herbicides it sells.
Nufarm managing director Greg Hunt said glyphosate was subject to stringent regulatory controls.
"Glyphosate is the most widely used herbicide in the world,and farmers rely on it to protect the health of their crops. It's been used for 40 years and there is a large body of scientific studies that supported this safe product when used in accordance with label recommendations,"he said.
"We will continue to monitor this case,however,decisions relating to the continued use of glyphosate are ultimately a matter for the regulators,"he said.
The Australian Pesticides and Veterinary Medicines Authority said glyphosate products registered with the APVMA were"safe and effective if used according to the label directions".
President of the Victorian Farmers Federation David Jochinke said glyphosate was an important herbicide in Australian agriculture that enabled environmental benefits,but that it should be used carefully.
“The chemical itself is quite important,however,we do encourage everyone to use it in an appropriate manner with the right equipment.”
Mr Jochinke said the VFF kept a watchful eye on all rulings and that the judgment highlighted “no-one should be complacent when they’re using any chemicals”.
National Farmers Federation president Fiona Simson said glyphosate was used in Australian farming systems as part of a"toolkit"of measures to control invasive and noxious weeds and to enable farmers to grow productive food crops.
"It is used broadly because science has established that it is safe to use,"she said.