The request follows a Ministry of Health study on lead poisoning of East Otago drinking water sources.
The report, which was published at the end of March, states that stronger control of drinking water is required, as well as a revision of plumbing requirements for lead in taps and pipe fittings.
The East Otago contamination, where lead levels tested as high as almost 40 times the acceptable limit for drinking water, is still being investigated, but household taps and pipe fittings containing lead are widely used throughout this country.
University of Canterbury director of environmental science Sally Gaw said there should be no lead in taps for drinking water, and it was important the review into plumbing standards is done.
“Lead is a neurotoxin, it’s not great at all for young children or babies to be drinking water that contains lead. [Only] a very low level of exposure to lead is considered to be safe – if at all,” professor Gaw said.
The heavy metal is also used in brass alloys. In 2018, the Master Plumbers Association called for the government to prohibit the selling of plumbing materials containing unsafe amounts of lead.
The organisation had five New Zealand-supplied taps checked in a laboratory and discovered that one of them leached lead at levels that were 70% higher than either New Zealand or Australian requirements.
Master Plumbers chief executive Greg Wallace said at the time that the issue was a latent threat, and that Australian study showed that 8 percent of a group of suburban houses had plumbing that was leaching lead into water at unacceptable levels.
“The drinking standard for New Zealand is far too high, we’re double the allowable level compared to Europe, Sweden and even China. So that needs to be reduced for a start, Wallace told Morning Report.
“The problem for New Zealanders, is there’s no way to identify this product – in Australia they have a system called Watermark… we’re calling for third party verification, we think the standards in New Zealand are not being policed, and the only way to police those standards is to have some sort of third party verification for products being sold.”
Professor Gaw believes that New Zealand’s ageing water supply system is a source of vulnerability.
She also supported a call for laboratories that examine drinking water to disclose any unnecessary exposure to the director-general of health, which was another recommendation in the East Otago lead contamination report.
She believes that the increased attention would assist in detecting complications as test reports are submitted to various agencies: “I believe that
is a great move forwards that would hopefully prevent things from being lost.”
A World Health Organisation fact sheet on lead said the metal had caused significant public health problems in many parts of the world, and “there is no level of exposure to lead that is known to be without harmful effects.”
Young children are especially vulnerable to exposure, which can cause “profound and permanent” health problems.
Lead exposure has been linked to irreversible brain development problems, behavioural disorders, difficulty learning, anger and violence, and kidney problems.
The US banned lead in new tapware in 1986, and Australian authorities are also considering drinking water exposure from plumbing fittings
A new national agency, Taumata Arowai, will regulate drinking water from July.
Taumata Arowai was founded in the wake of the Havelock North water contamination connected to the death of four people, and the poisoning of at least 5000 people, after which led to a government inquiry that found systemic failings in the regulatory framework for drinking water.