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Glyphosate safety could be put under the microscope again.
The Environmental Law Initiative (ELI) is pushing for a review of the herbicide, saying new evidence shows it is detrimental to the environment and human health, and pointing out that the Environmental Protection Authority (EPA) last reviewed it in the 1970s.
Director for research and legal at ELI Matt Hall said the organisation has submitted a form detailing grounds for reassessment to the EPA under section 62 of the Hazardous Substances and New Organism (HSNO) Act.
An Official Information Act request the group submitted to the EPA in November last year showed there are 90 approved substances containing glyphosate in New Zealand. The ELI has submitted a list of 83 substances it wants reviewed, Hall said.
The submission is the first step in the process towards a reassessment, he said.
New evidence shows glyphosate and co-formulants have significant effects on aquatic and terrestrial ecosystems, impact the human nervous and endocrine systems, and are probable human carcinogens, he said.
“We will likely request the EPA investigate the key issue of glyphosate co-formulants, which have been shown to be potentially more toxic than glyphosate,” he said.
Manager of hazardous substances and new organisms at the EPA Dr Chris Hill said if significant new information related to the effects of a substance becomes available, a decision-making committee may decide there are grounds for reassessment.
“While glyphosate has not been subject to a reassessment, the EPA continually reviews the information available on the substance, both within New Zealand and globally,” Hill said.
Glyphosate was approved for use before the HSNO Act came into force in 1996. Following the Act coming into force, a number of glyphosate-containing substances were moved into the HSNO framework during the “transfer” process in 2004, the EPA said.
Professor of Toxicology at the University of Canterbury Ian Shaw said he agrees that there is new evidence and glyphosate needs to be reviewed.
“I’d like the scientific evidence to be looked at in a risk/benefit context,” he said.
“We need to perhaps adjust the way we use it.
“I don’t necessarily think a review is going to lead to anything terrible. We need to look at the new data. We need to look at the different ways glyphosate is now being used. When it was originally licensed in the 1970s the use pattern was very different and the amount used was smaller,” Shaw said.
There are people lobbying from all directions and the only way to break that conjecture is to look at the data, he said.
“What makes me anxious is when the economic benefits are brought in, because there’s no question that glyphosate has a huge economic benefit for farmers, but that’s not what we’re talking about here. We’re talking about impact on the environment and the health of consumers,” Shaw said.
Canterbury arable farmer Hamish Marr, who completed a Nuffield scholarship that focused on glyphosate, said by using glyphosate farmers minimise cultivation and allow for environmentally friendly techniques such as direct drilling and minimum tillage.
Without glyphosate, cultivation doubles because growers have to control weeds, often through ploughing, he said.
Less tilling leaves soils in better condition and keeps carbon and nitrogen in the soil, he said.
Because NZ predominantly focuses on pastoral farming, exposure to glyphosate is less than in Europe or North America, he said.
Alternative chemical options are more toxic, he said
Marr said if arable farmers stop using glyphosate, or if all growers adopt organic practices, the world’s farmers will simply not be able to grow enough food to feed the world’s population.
The EPA is stretched in its efforts to review and release new, more effective and more integrated pest management-friendly chemistry, and unnecessary chemical reviews such as this hold up the EPA and hinder it in efforts to do its core tasks, he said.
