Elevated levels of arsenic have been detected in an established Frankton residential subdivision.
The levels are below the national environmental standard for recreational activities and parks (80mg of arsenic per kg of soil) but some are above the standard for residential land (20mg/kg).
Queenstown Lakes District Council said today it had been working with the Medical Officer of Health and the developer of the subdivision, Remarkables Park Ltd (RPL), to establish the extent of the issue and to provide advice to the community.
Residents and property owners were advised by letter today and have been invited to a community information session in Frankton tomorrow.
General Manager Planning and Infrastructure Tony Avery said the information came to light after RPL performed tests as part of routine preparations for the next stage of its development.
RPL also sampled a small number of sites in the adjacent developed residential area. The results were shared with QLDC, which informed Public Health South and the Otago Regional Council.
QLDC then commissioned a further set of samples to be taken on road reserves in the vicinity. These also showed arsenic levels that were lower than the level permitted for recreational activities (80mg/kg, which is the closest category of the standards relating to roadside reserves) but often higher than the permitted maximum of 20mg/kg on land used for residential purposes.
Contractors engaged by RPL brought in soil from elsewhere in the 1990s when the subdivision was being developed to establish the roads and berms, but it was not used within the sections that were built on. The source of the imported material is not known.
The Medical Officer of Health, Dr Derek Bell, said the level of arsenic on a property would need to be established to understand the degree of personal exposure and any personal health effects.
“Exposure would be dependent on the amount of soil ingested through gardening activities and from eating home-grown produce and the duration of that exposure,” he said.
Eating soil was most commonly associated with small children.
“The health of people with no exposure or limited exposure is unlikely to be affected.”
Dr Bell said the environmental standards were very precautionary and assume that a significant proportion of a person’s diet came from home-grown produce over a lifetime.
“Generally, at the levels of arsenic observed so far, health effects would not be expected,” he said.
He advised anyone with health concerns to consult their general practitioner.
Brian Fitzpatrick, the Development Manager at RPL, said that when the subdivision was developed in the early 1990s, the company complied fully with all regulations and there were no requirements to test the soils.
The National Environmental Standard soil guidelines were introduced in 2012.
