The level of distrust in science and experts is getting worse in New Zealand, the Environmental Protection Authority says.

Photo: AFP

The Environmental Protection Authority lays most of the blame with the "unmoderated milieu of the internet" and this makes it difficult for the authority to explain decisions.

Authority chief executive Allan Freeth said there was a growing trend of science denial in New Zealand, consistent with a global distrust in authority figures and institutions.

"Particularly with the rise of social media, I think that has led to a rise of growing cynicism and suspicion about science. In this case it's about science - but in other cases it can be about any issue that authority figures talk about."

Dr Freeth said the speed at which some myths spread online meant agencies like the EPA simply did not have the tools to be able to deal with them.

He said that could be problematic when the public needed to understand why the organisation had made a decision.

"New Zealanders either have to understand the science or they have to be able to have trust in us as an organisation, but it really helps if they understand the science or they are prepared to listen to the scientific evidence.

"So when there's a view that no matter what we say it's not going to be taken or believed then our effectiveness as a regulator is impacted."

Crank theories

Environment Minister David Parker said in some cases crank theories had to be called out as just that. But he said it was important that everyone could air their views.

"In order to maintain public confidence in those sorts of decisions you have to run public processes that enable critics to have their say, but then civil society, once those processes have been run and independent people have made their proper decision, the rest of us have to respect those decisions."

The former environment minister, National's Nick Smith, said the EPA raised a fair point.

"I think there is a sort of an undercurrent in New Zealand, whether it comes to issues of 1080, genetic modification and on the opposite environment end around climate change, of wanting to rubbish the mainstream science.

"I think it is just so crucial for New Zealand, which prides itself on its clean green brand that we make those decisions on the basis of the very best science."

In the EPA's report it labelled science deniers as being opposed to, among other things, fluoride, 1080, vaccinations, genetic modification and glyphosate.

Former Green Party MP Steffan Browning has long campaigned against the use of glyphosate.

The chemical has been used by farmers for more than 40 years, but its safety was cast in doubt when a World Health Organization agency concluded in 2015 that it probably causes cancer.

Mr Browning said the EPA was defending its decision to continue allow glyphosate's use in New Zealand and was trying to tar detractors as anti-science.

"That is not the situation. It is identified as a probable carcinogen, it's an endocrine disruptor, it's a neurotoxin.

"To put those concerned about glyphosate, the effects on our children, the effects on our community, as some sort of science deniers is very irresponsible on the part of the EPA."

He said while there were some extreme views out there, it was patronising and anti-science to label people who questioned the EPA's decisions as science deniers.