Soil tests point to an identifiable pollution source
Comprehensive approach to community comtamination still nowhere to be seen
By Timothy Lambert
The two pairs of graphs represent results of extensive soil testing for lead and arsenic
in areas well removed from the tar ponds and coke ovens site (top graphs) and in
Sydney neighbourhoods closest to the sites (bottom graphs). Besides illustrating the
much higher frequency of high-concentration samples close to the former steel
industry sites, correlation between the distributions of lead and arsenic (illustrated by the similarities in the bottom graphs) suggests a common source, according to
expert Timothy Lambert.
The editorial in the Cape Breton Post entitled "soil picture mostly murky" has done just that, created a very murky picture by contrasting two very different communities with the communities surrounding the Sydney tar ponds. Furthermore, the editorial confuses the difference between the Canadian guidelines for lead and those of the US EPA.
The Canadian guideline for lead is 140 ppm and is health risk based. The US EPA guideline of 400 ppm is a hazard guideline "which would result in adverse human health". The number was based on cost-benefit analysis. The EPA also says it recommends action below the guideline if children under 6 will be playing in the area.
Thus the Canadian and US guidelines are different.
The three communities in the editorial are significantly different.
The Lynnview community in Calgary is 20 years old and was built on part of the former Imperial Oil refinery site. Lead paint is not an issue. The lead contamination is from the surface and extends down at least 1.5 metres, ranging from 50 to about 8000 ppm.
Testing suggested lead was entering the homes. Parents were cautioned to ensure that children do not eat soil and to wash their children's hands to avoid exposure to lead.
In August 2001 the residents of Lynnview were offered a buy-out by Imperial Oil, who was named in an Alberta Environment protection order the responsible party, which has allowed many residents to leave their contaminated community.
St John's is more than 200 years old. The goal of Trevor Bell's sampling in St. John's was to determine whether high levels of lead exist in soils.
The sampling targeted areas likely to contain high lead levels, like the drip line along old homes where leaded paint would be found and in yards where coal ash could be observed; Dr. Bell commented that the coal resin in soil stained the fingers.
The high median value for lead in the downtown core, 1076 ppm, reflects the drip line sampling and lead from paint. The arsenic median value was 10 ppm - below Canadian guidelines of 12 ppm. The lead and arsenic were not correlated, and paint has not been found to be a source of arsenic.
In St. John's, the Medical Officer Dr. Allison cautioned parents to wash their children's hands often and not to let them play in contaminated soil.
Clearly a responsible party would be difficult to identify as the contamination is largely a result of lead paint and 150 years of coal burning. Therefore in this case, the question of who should remediate the properties is difficult to answer?
The tar pond communities are less than 100 years old. The soil sampling focussed away from any houses or buildings, which may contain high levels of lead from paint.
The goals of the sampling were to capture neighborhood-wide levels to determine if the three neighborhoods surrounding the site - Whitney Pier, Ashby and North End Sydney - are contaminated and if there appears to be a common source.
The results were published in Environmental Health Perspectives (January 2004).
The results found that lead, arsenic and PAHs were highly correlated suggesting a common source.
The lead and arsenic were also correlated at the doorways suggesting the contaminants found in the homes originated outside. The lead, arsenic and PAHs were above Canadian guidelines.
For arsenic, 20 percent of the background soil samples and 95 percent of the tar pond soil samples were above the Canadian health-risk-based soil guidelines (12 ppm ). The mean arsenic value was 67 ppm.
For lead, 5 percent of the background samples and 80 percent of the tar pond soil samples were above the Canadian lead guidelines (140 ppm Pb). The mean lead value was 388 ppm.
In addition, some residents in Sydney have contamination in their basements, which seeped in through cracks in the foundation; this is not the case in St. John's or Calgary.
I advised parents to follow similar advice as offered in St. John's and Calgary.
Furthermore, our household survey found that the residents in Whitney Pier, Ashby and North End observed the soot and air pollution in their community when the plant operated whenever the wind blew it in their direction.
The historic air monitoring by Environment Canada documented the pollution in the communities. Health Canada warned the Nova Scotia government that the pollution from the coke ovens and steel plants were likely causing health problems for the residents.
Furthermore, Paul Moore of Health Canada has said in the Cape Breton Post that the contaminants found in Whitney Pier adjacent to the coke ovens site are present for 3 km surrounding the industrial site, consistent with our results.
At this time, the communities have been largely excluded from the tar pond remediation policy. Some select homes have been offered buy-outs with no rationale provided to all the residents.
I agree with the Government of Canada who "subscribes to the policy that the polluter should pay for the cleanup (the "polluter pay" principle). The regulatory authority which allowed such contamination is next in line of responsibility."
The real murky question is: when will the responsible party for Sydney's contamination provide a comprehensive strategy to address the contamination and public health concerns in the community as a result of the century of coke ovens and steel plant operation?
Timothy Lambert, PhD, is
Adjunct Professor of
Community Health Sciences,
University of Calgary.