New Zealand officials are wrong to underplay the risks from firefighting foam that's contaminated water supplies to an undetermined extent, an American public health expert says.
Photo: 123RF
Environment Ministry chief executive Vicky Robertson spoke to Morning Report yesterday on behalf of the government group managing the contamination at the Ōhakea and Woodbourne air bases.
She said the government had first learned of the contamination in October last year and decided to do more testing to find out the extent of the contamination
It was the first time government officials agreed to an interview on the topic.
The Defence Force previously admitted chemicals used in firefighting foam before 2003 had leached into nearby soil and water at the Ōhakea and Woodbourne bases.
The contamination was discovered in June 2015, but the first that nearby households knew of it was December 2017 when the seven households found to have been contaminated beyond drinking water safety guidelines - set in April 2017 - were informed.
Ms Robertson denied the Ministry's decision to withhold the information from people who could have been affected was wrong.
"What we're balancing here is going out to having a public statement about contamination, to actually going and finding out where the contamination is hitting and who is affected and giving people a bit more certainty about how it affects them," she said.
"We weren't wrong, we really wanted to focus on those families that we knew were above the drinking water standard."
But American public health expert Howard Freed said that continually minimising the risks was a pattern of behaviour "doomed to fail" New Zealanders.
Dr Freed was director of New York State's Department of Health's Center for Environmental Health from 2008 to 2012 while that state grappled - and is still grappling - with the impacts of foam contamination on water supplies.
He said there were essentially two schools of thought in health risk management policy.
"One, which categorises some of the government agencies but not all, is what I will call a minimising approach and that is a concern to not worry the public unnecessarily and to wait for conclusive proof of harm before acting to protect the public," he said.
"The other side of the argument is what's called the precautionary principle which essentially holds that regulators and other decision makers responsible for public health should act to protect the public when there is evidence of harm and not wait for conclusive proof, especially when conclusive proof is unlikely to become available in the foreseeable future."
The New Zealand government appeared to be taking the minimisation approach, he said.
"Something I did notice is that the New Zealand authorities were saying there is no conclusive evidence of harm.
"Another way to say the same thing is there is evidence of harm - there is - it's just not 'conclusive' in their professional opinion."
The science existed but the key was in how the risk to the public was interpreted, he said.
"If the risks are minimised as a general rule, then sooner or later that is a government policy that is doomed to fail the people because the actual risks - we know - of some of these chemicals is quite severe, we just don't know which chemicals."
The most prudent public policy would be to warn the public.
"The New Zealand authorities were quite clear that there are no acute health effects. That means that if you drink a glass of water you're not going to keel over, that's an acute health effect.
"The question is about chronic drinking of the water and chronic health effects such as the development of cancer and liver problems.
"These PFAS they are chlorine-saturated chemicals, and they bioaccumulate, which means they will be concentrated in the body."