Toxic coal tar delays works at city site | Auckland News | Local News in Auckland

Children with low resistance to infections may have been inhaling carcinogenic coal tar particles as they make their way down Grafton Rd to the refuge of the Child Cancer Foundation.

Many walk the short distance from Starship Hospital with Nasal drips in place to take time out and have a meal, watch a DVD or talk to others.

Child Cancer office manager Paula Elder is upset Auckland Transport hasn't advised the foundation that the $1.1m upgrade of Grafton Rd has been delayed by coal tar contamination at the site.

"We knew nothing about any contamination or [potential] health risk."

Mrs Elder is concerned if coal tar is present, anyone inhaling it could be in danger. "We would expect to be told and would get advice from a health professional. If there was a chance human health was being compromised we wouldn't send families down this way."

Auckland Transport says a new resource consent is being sought to remove the toxic waste to an approved facility and admits there's a risk to the health of road workers who touch it.

Sharon Hunter, Auckland Transport's communications manager, confirms residents and nearby workers were not advised of the contamination: "The site is fenced off, restricting public access and therefore there is a low risk," she says.

Dust clouds from road works were blowing around buildings when The Aucklander visited on Friday. But Ms Hunter says that dust was from concrete.

Asphalt containing more than 150mg/kg of coal tar is deemed hazardous waste in Europe. Yet it can be found in quantities of up to 7000mg in New Zealand. A 2009 New Zealand Transport Agency report says most streets built before 1970 - and which haven't been reconstructed - are likely to contain coal tar below the surface.

It says there's potential for exposure to humans and the environment and the "lid is already off Pandora's box" in Europe. The cost of dealing with the contamination here would add millions of dollars to road rebuilding projects.

A US study, published by Environmental Health Sciences in 2009, found coal tar-laden dust could be ingested by hand-to-mouth contact. The dust could be carried indoors on shoes or inhaled while working or playing outside.

Green Party toxicology spokesperson Catherine Delahunty says New Zealand has a number of toxic legacies and coal tar is one.

"Protecting Grafton Rd residents should have been the number one priority when this was detected. Auckland Transport should have informed residents and introduced a dust management strategy including putting up solid barriers and watering down any dust."

She says it is impossible to prove a person could get cancer from breathing in the dust, but Polycyclic aromatic hydrocarbon (PAHs) found in coal tar are a known carcinogenic and taking a precautionary approach was vital.

University of Auckland senior lecturer in organic and medicinal chemistry, David Barker, says coal tar is banned in several countries and its dust can be carcinogenic if inhaled in large quantities. "Historical studies show that chimney sweeps or those who work in the manufacture of asphalt are the ones who may get cancer," he adds.

However he says it is also used in some skin care products which over decades of monitoring have shown no harm to users.

Pesticide Action Network's Dr Meriel Watts says coal tar is a serious problem few New Zealanders were aware of. "Residents should definitely be informed and yes, the dust is likely to contain hazardous contaminates and it should be contained."

Ms Hunter says the source is either historical use of coal tar as a waterproofing material in the pavement, or contaminated waste when Grafton Rd was originally built.

"In the past, waste material from the production of coal gas was used as a fill under roads and as a levelling material. At the time, little consideration was given to its toxicity."

Coal tar binders were widely used for roads in New Zealand until the 1970s, and the 2009 NZTA report says a "large proportion" of older city streets still contain the carcinogen.

It estimates 50 per cent of Christchurch's streets are affected. Ms Delahunty said the problem "will be an emerging issue during the rebuild".

She says she is negotiating with Environment Minister Nick Smith to develop guidelines to address the issue.

"Despite the cost, we have to face up to the legacy of what we've done in the past. Until we develop non-toxic ways of disposing of these chemicals we have to contain them in a safe environment."

The Grafton Rd contamination didn't show up in design-phase tests. The upgrade, including resurfacing, channel reconstruction and new footpath, was due to be finished by the end of February, but is now expected to take until mid-March.

Ms Hunter says there will be additional costs but exact figures depend on the resource consent.

She confirms risks to the public and the environment, but says the upgrade requires a council-approved management plan to control stormwater discharge and handling procedures.

Martin Fine, who works on Grafton Rd, told The Aucklander he and his colleagues sometimes stand outside during break times. He is concerned about breathing in the "waste".

"We were contacted by Auckland Transport and advised the roadworks would take longer, but had no idea about any health issues. We'll have to take steps to advise staff. We need to stop and assess the right information so people know what's going on."

Footnote: Following publication of this story in The Aucklander Ms Hunter wrote to us to say people have now been advised of the contamination. She said a letter was sent on Tuesday "as part of a regular update" provided to those living in the proximity of Auckland Transport's major projects.

The letter does not advise residents about exactly what coal tar contamination is but Ms Hunter said the site is safe and sealed.

The letter says: "The process to manage the material coupled with recent bad weather, has delayed work on the site and further updates will be provided in due course."

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