Brian Rudman: Secrecy over preschool soil-testing led only to over-reaction

You can't fault Auckland City Council for checking for contaminants in the soils of certain preschools. But why did they ruin all the good work by banning the news media from the public meetings where the results were unveiled?

Perhaps if the parents were being advised their kids were at risk of their arms and legs falling off, I could appreciate the need for a little privacy. But why have highly paid bureaucrats lurking about, accusing journalists of eavesdropping through keyholes, when the news being announced was basically good.

Sure, testing soil at two Freemans Bay preschools had revealed elevated levels of potentially cancer-causing polycyclic aromatic hydrocarbons (PAHs). But the risk to the health of children who were current - or past - pupils is, given current knowledge, minuscule. Council health adviser, environment health specialist Dr Tim Sprott says the kids are 10 times more likely to contract cancer from breathing Auckland's polluted air than they are from ingesting or breathing in any playcentre PAHs.

All the secrecy did was encourage speculation and over-reaction. Such as that of the mother of a 13-month-old daughter, who has linked her baby suddenly erupting in red blisters and developing a temperature of nearly 40C on Tuesday with the soil contamination.

Once the council had tested the soils and discovered it contained higher levels of benzo-a-pyrene (BAP), the PAH involved, than recommended by Environment Ministry guidelines, it had to act conservatively and arrange to have it replaced.

But the episode does raise again the vexed question of how far we go, as a community, to try to protect ourselves from the risks of living in the modern world.

To return to Dr Sprott's example, pollution levels in Auckland air will probably be responsible over a lifetime for an extra 30 cases of cancer per million people. One of the major pollutants in the air is the same chemical as found in the playschool soils. The airborne culprits come mainly from internal combustion engines, whereas the city council assumes the playcentre BAP comes from soil brought on to the site from the old Beaumont St gasworks.

BAP, it seems, is everywhere, a product of the burning of organic material. One can absorb it from smoked, grilled, barbecued or burned foods, from second-hand tobacco smoke and even roasted coffee, cereals and vegetable oils. And, to raise a specifically Auckland source, volcanic eruptions. Of course if the local volcanic field got suddenly restless, I suspect avoiding excess BAPs will be the least of our worries.

Still, raising the risk of volcanic eruption does put the present scare into some sort of perspective. With death by car and shark attack.

The last time we fretted about our soil was back in November 2004 when Environment Minister Marian Hobbs got us all a-twitter with her demand that we prepare a Domesday Book recording the history of every bit of soil in Auckland. She was hot on the trail of any traces of DDT and other toxic nasties left over from former market garden activity, and wanted to identify the hot spots. The Auckland Regional Council got into the act with a report saying up to 6000ha of the region was ex-horticultural and thus suspect. Various councils then followed through with plans to label suspect lands unclean.

Eventually, a certain degree of sanity was restored, and Auckland's soils were left to lie unchecked. Early in 2005, Auckland City and the ARC did endeavour to embark on a pilot study and wrote to 100 owners of sites identified as potential pesticide hot-spots - sites of old glasshouses or spray sheds - asking for permission to test. Less than 10 per cent agreed and the project was abandoned because there were too few properties for a scientifically valid trial.

The reluctance to participate was hardly surprising. The sting was that if a property proved to be contaminated, the owner had to reveal the fact on the property's "warrant of fitness" type LIM report.

Returning to the preschools, it was good of Auckland City to single their soil out for priority testing, but it is curious it shows no interest in testing the soil of adjacent properties, which presumably share the same BAP-polluted fill. Mind you, if I was the property owner, nor would I.