New Zealand's environment watchdog has found glaring gaps in the way we manage the tens of thousands of chemicals in use across the country - with just a fraction being routinely monitored.
In his latest report, Parliamentary Commissioner for the Environment Simon Upton has called for all government agencies dealing with chemicals to adopt a common plan to manage them.
Upton also wanted to see better data and monitoring, after finding some clear gaps in oversight.
While roughly 30,000 have been approved for use in the country, fewer than 200 are routinely tracked as part of environment reporting or through resource consent monitoring.
Governing the use of chemicals here largely fell to four main regulators – the Environmental Protection Agency (EPA), Medsafe, WorkSafe NZ and the Ministry for Primary Industries.
The EPA remained the key agency responsible for managing environmental risks from chemicals, and assessed applications to use new ones here.
Yet only about 3500 substances have ever been the subject of individual approvals requiring specific environmental risk assessments, with most approved as a group.
There remained no formal risk assessment for weighing up the risks, costs, benefits and effectiveness of individual substances, simply because of the sheer size of the task.
Currently, evidence relating to individual substances weren't evaluated by the EPA unless the chemicals had to be formally reassessed – something that happened in only a handful of cases each year.
"On paper, there is a robust system in place to assess risks when a chemical is introduced to the country," Upton said.
"But many chemicals that have been in use for decades have not been subject to close scrutiny."
Much of the science on their environmental impact had changed, he said, and rules about how a chemical could be used shouldn't be static.
"We need to be able to adapt as new information comes to light," he said.
"Restrictions should be based on the latest science and informed by New Zealand-specific data on use and impact."
While not all chemicals posed a high level of concern, Upton said there was much we didn't know about those reaching our environment. That included how much was used, where they were used, and what effects they were having.
Although there had been a few studies aimed at establishing baseline levels of emerging contaminants, these hadn't been conducted for each ecosystem - or with sufficient regularity.
"Finding out after chemicals have caused irrevocable impacts on the environment is too late."
A common framework for all agencies involved with chemicals - developed with Māori, and focused on those presenting the biggest risk - could help manage their impact.
To gauge the scale of a chemical's use here, he recommended collecting and sharing data throughout its lifecycle – something that'd require importers, manufacturers and sellers to up their reporting.
"If we know what is being used and the regional distribution of that use, we can then organise our environmental monitoring to match the scale of chemical use," he said.
"While we cannot test every ecosystem for every chemical in New Zealand, we can do more to target those of highest potential risk to the environment."
New Zealand also needed to do a better job of setting limits for acceptable concentrations of chemicals in the environment - and monitoring whether these levels were being exceeded, he said.
"In a perfect world, if chemicals are used in the way they are approved to be used – taking into account their likely environmental fate – then what we see and find in the environment should be at acceptable levels," he said.
"But theory rarely matches reality."
Associate Environment Minister Phil Twyford said Upton's report raised "some important issues which need to be addressed" and the Government would give it serious consideration.
Experts have also welcomed it.
"Right now, New Zealand relies on international literature for guidance on toxicity for a range of chemical contaminants in our environment," GNS Science environmental chemistry team leader Dr Magali Moreau said.
"Better local data and reporting will support our understanding and management of emerging chemical contaminants, particularly where international literature is not available, and compounds could then be prioritised for research."
Massey University environmental chemist Dr Nick Kim said the report offered, for the first time in New Zealand's history, a "rational way forward".
"To properly manage the environmental risks posed by chemical use, we need to think more widely."
Kim noted that chemicals themselves varied widely – from naturally-occurring heavy metals to synthetic pesticides, and from relatively non-toxic to highly toxic.
"We know that some otherwise safe chemicals – when released on mass – can compromise or destroy entire ecosystems."
As Upton's report acknowledged, Kim said tracking everything was impossible.
"The best we can do, even with a sizeable budget, is monitor for a tiny target subset of the chemicals that are in use, in some places, some of the time," he said.
"That raises the very real problem that in focusing on managing the subset of things that we do know a lot about, we may miss the significance of larger events that are going on right under our noses."
But having a common framework among agencies, he said, would go a long way in addressing current gaps.
"I hope this report serves to catalyse that shift."
EPA chief executive Dr Allan Freeth said the agency also supported that concept.
"For some time, we have been signalling a growing concern about the need to better understand the lasting impact of chemicals and their pathways into the environment," he said.
"This report aligns with our strategic efforts to take a long-term approach to regulation, and gives voice to issues we know matter to all New Zealanders."