Dusty Shelf Beckons Study

Picture by Dan McMullin

Study On Household Dust Adds Nothing To Relocation Cause

The Issue: Slight Risk Claimed
Cape Breton Post Editorial
Wednesday, April 7, 2003

Perhaps like Muhammad Ali in his 1974 Rumble in the Jungle against the heavily favoured heavyweight boxing champion George Foremen, the Sierra Club and its intrepid band of dissenters are playing Rope-a-Dope on the Muggah Creek cleanup. They're pretending to be beaten, lulling their tiring opponent into inattention and over-confidence before bouncing off the ropes with a flurry of decisive blows.

But judging from the latest counterpunch, the results of a study on household dust, this loosely constituted, unofficial opposition party to the cleanup bureaucracy is running low on energy and effective ammunition.

The dust study, largely a volunteer labour overseen by University of Calgary community health science professor Timothy Lambert, concludes that there is "a low but significant health risk from exposure to lead and arsenic in the soil and house dust" in the three Sydney neighbourhoods where household samples were taken. The study is under the auspices of the People's Health Com mission, a brainchild of the environmental lobby organization, Sierra Club of Canada.

If Lambert's study sounds less than the smoking gun that would be required now to shift public and political perception from where it has congealed on questions such as residential relocation, he sounds even less convincing when he describes how the conclusion of risk was reached. "The doorway concentrations are 10 times higher than inside the homes, and based on that we sort of gave a prediction of the health risk of a one to 15 per cent chance of a child's likelihood of having elevated blood lead, and probably arsenic as well."

Lambert says his conclusion that there's a slightly elevated risk of health effects from tracking contaminated dirt into homes is consistent with findings of the blood and urine tests on 372 people, mostly children and pregnant women, conducted in 2001. That study by the provincial Department of Health and the Cape Breton District Health Authority concluded that "this community is not at increased risk from lead in soil. On the community level, arsenic exposure is also low."

Lambert achieves his consistency by arguing that the risk threshold used in that 1991 study, 10 micrograms of lead per decal itre of blood, is too high by a factor of two. Setting a threshold of five decalitres, we see a slight risk to some children in the 1991 data.

But any such numbers can be disputed in scientific and policy circles, and the numbers adopted are always defended as ultra-conservative, so as not to exclude any possible risk. In any case, even allowing Lambert his stricter standard, his conclusions fall short of the dramatic and add nothing significant to the Sierra Club's adopted cause large-scale relocation of residents from around the tar ponds and the coke ovens site.

The dust swab results appear to belong to the urban environment problem. The dust study is consistent with others including the still unreleased Sydney Urban Area Statistical Report, an extensive three-kilometre soil testing exercise which indicate that no neighbourhood of Sydney is more contaminated than another, and that the contamination is more or less consistent with what one would find in any urban environment, especially one with a long industrial history.

Lambert's study looks pointless because, unfortunately, we've learned to read such things in adversarial terms. One supposes its original purpose must have been to advance the Sierra Club agenda, and it has turned out to be not very useful in that regard.

Still, there's a cautionary note here that conscientious parents in particular can't ignore. A community truly committed to improving its health would read things like the dust study for what they might usefully say about lowering the risks to children even when the official view remains that there is no recognized risk. The polarity of cleanup politics works against this attitude but in the end it should be the one that prevails.