WARNING: Graphic images

AUSTRALIA’S top-tier cancer body has called for an independent review of the world’s most well-known herbicide which has been linked to non-Hodgkin’s lymphoma.

An active ingredient in the popular weed-killing product Roundup called glyphosate — a chemical that has not been reviewed in more than two decades — Cancer Council is concerned.

Roundup is the most widely used herbicide on the planet and is popular among domestic gardeners and farmers in Australia. It was patented by agrochemical company Monsanto four decades ago and is now part of pharmaceutical giant Bayer.

More than 500 glyphosate products are sold in Australia today.

In 2015, the flagship weed killer had come under increased scrutiny following the World Health Organisation’s determination that glyphosate, is “probably carcinogenic to humans”.

“We are concerned that this issue’s not being taken seriously enough in Australia, particularly by the agricultural industry,” Cancer Council Australia CEO Dr Sanchia Aranda told the ABC’s Four Corners. “The IARC report is independent and does suggest that there is absolutely a reason for concern.”

Roundup was marketed to farmers and home gardeners across the world as safe and effective.

“It is the safest herbicide that’s ever been developed,” said Bayer vice-president Scott Partridge.

Bayer recently bought Monsanto for $63 billion.

But this hasn’t been the case with thousands of lawsuits yet to go to trial.

Recently a former school Californian ground keeper claimed Monsanto’s ‘cancer-causing’ weedkiller destroyed his life.

A jury ordered Monsanto to pay Dewayne Lee Johnson $US289 million ($A410 million) after it unanimously found that the company’s Ranger Pro and Roundup products presented a “substantial danger” to consumers, and that Monsanto knew or should have known of potential risks and failed to warn consumers like Mr Johnson.

According to the ABC, the trial blew the lid on a decades long campaign by Monsanto to protect its flagship product.

A trove of company documents, known as the Monsanto Papers, reveals a history of the company ghostwriting articles in support of glyphosate, attempts to undermine the IARC finding, and internal concerns about the safety of Roundup.

In one email from 2003, Monsanto’s lead toxicologist warns the company cannot say that Roundup is not a carcinogen because they have not done the necessary tests, the publication reported.

“For the last 20 or 30 years, Monsanto has engaged in a systematic and deliberate campaign to attack any science that says their product is not safe and to attack any scientist that has the courage to say something,” said Brent Wisner, a lawyer on the legal team which won the landmark case.

“They have a corporate culture that has zero interest in safety. It has only an interest in maintaining the ability of them to sell this product.”

Monsanto said the documents revealed in court were “cherrypicked” and insisted more than 800 studies and reviews showed glyphosate was safe.

The company is challenging the jury verdict.

In America, more than 9,000 people are now suing, claiming Monsanto’s Roundup products led to their cancer.

Australia’s regulator, the Australian Pesticides and Veterinary Medicines Authority (APVMA), has not formally reviewed glyphosate since 1995.

The regulator did a scientific evaluation of the IARC report and decided there was no reason to formally review glyphosate.

“Glyphosate remains safe to use in the Australian environment,” APVMA chief executive Dr Chris Parker told the ABC.

Concerns have been raised about the regulator’s independence because it is primarily funded by the chemical companies it regulates.

“Governments have an obligation to fund these kinds of agencies with public money so that transparency and independence can be assured,” Dr Aranda said.

The APVMA insists it acts independently of industry.

“Our decisions are our decisions, they’re not able to be influenced by politicians or industry,” Dr Parker said.

Watch The Monsanto Papers, tonight on Four Corners at 8.30pm on ABC TV and iView.