Emerging public and occupational health hazard?
Scientists have learnt that a little known mineral distributed within rock in the Auckland region has the potential to cause mesothelioma if it is disturbed during construction excavation.
The NZ Medical Journal reports the mineral, erionite, is likely to have been present in the vast amounts of rock excavated in major civil works such as the recent Waterview Tunnel and the current City Rail Link project. (Safeguard)
Erionite is now classified by the IARC as a Class 1 carcinogen and is likely to be more potent than asbestos.
However, there are as yet no occupational exposure limits for airborne erionite mineral fibres.
A number of useful areas of research suggested are to:
- establish the source occurrence of erionite in the Auckland region;
- establish the degree to which erionite dust is transported in the air;
- understand the exposure to erionite dust in the construction workers most at risk;
- establish testing regimes and occupational exposure limits;
- establish appropriate management of the risk posted by erionite in major Auckland construction projects.
Some of the deaths due to mesothelioma previously assumed to have been caused by exposure to asbestos could have had erionite as a contributing factor (as noted in report).