killer@ (New throughout, adds background on weed killer, details on Brazil agriculture)
SAO PAULO, Aug 8 (Reuters) - Brazil-based agrochemical companies plan to appeal a ruling suspending the use of best-selling weed killer glyphosate in one of the world's largest grain producing nations, an industry spokeswoman said on Wednesday.
Glyphosate, an herbicide widely sprayed on soybeans, corn and other crops that have been genetically modified to tolerate it, was suspended in Brazil by a court ruling last week pending a government reevaluation of its toxicity.
Silvia Fagnani, executive director of a pesticide industry group known as Sindiveg, said the appeal in Brazil would be filed by next week. She said Brazilian health agency Anvisa, as well as the Agriculture Ministry, were also going to file separate appeals against the decision to suspend glyphosate and another two chemicals used in agriculture.
Anvisa, which started reevaluating glyphosate, insecticide abamectin and fungicide thiram in 2008, did not immediately reply to a request for comment. The ministry confirmed the intention to file an appeal in statement sent to Reuters.
The agrochemicals toxicity reevaluation started when new evidence surfaced that glyphosate and the other two chemicals included in the ruling "could pose danger or risk to human health," court filings said referring to the Anvisa process.
Monsanto, now owned by Bayer AG, is the biggest seller of glyphosate products in Brazil.
But a federal judge in Brasilia ruled last week that new products containing that chemical, as well as abamectin and thiram, could not be registered in the country pending the Anvisa reevaluation.
Existing registrations would have to be suspended within the next 30 days, until the government reevaluates their toxicity, the ruling said.
Fagnani said glyphosate is safe and authorized in many countries. She said sale and commercial use should continue in Brazil until the Agriculture Ministry, responsible for registration of agrochemicals, publishes any decision otherwise.
The World Health Organization in 2015 classified glyphosate as "probably carcinogenic to humans."
A qualified majority of EU member states agreed to re-authorize glyphosate late last year.
Last month, a federal judge in the United States ruled that hundreds of lawsuits against Monsanto by cancer survivors or families of those who died could proceed to trial.
"All of the system of direct planting is based on glyphosate, and it will be a gigantic environment setback (to suspend it)," Brazilian Agriculture Minister Blairo Maggi said.
(Reporting by Ana Mano; Editing by Lisa Shumaker and David Gregorio)