"The results of soil samples taken from a construction project near the
toxic Sydney tar ponds show high levels of contamination." - Steve
MacInnis - Cape Breton Post,
March 6, 1999
"Terry MacPherson, an inspector with the department, said the nearby tar
ponds are the likely source. Black goo seeped into the Prince Street
mall parking lot in January,
after poles and steel beams were pushed through the pavement to support
the new extension. A shopper
complained to the Environment Department after the sludge was tracked
inside the mall. No
work-stoppage order was issued, but contractor Joneljim Construction and
Atlantic Shopping Centres, owned by Sobeys, have been ordered to
complete a health-risk assessment of the project. Basically we've asked
for them to retain a toxicologist or risk-assessment firm ... and come
back, he said." - Tera Camus / Cape Breton Bureau.
Again, the authorities are reverting to "Health Risk Assessments." It
seems apparent from reading these articles (parts quoted above,) that
too many Nova Scotia Government employees do not understand what a
Health Risk Assessment can, and can NOT do. A human health risk
assessment is a computerized probability-based exercise in prediction
over time, requiring many assumptions to be made regarding the extent of
toxic contamination, rates of exposure, and the medical susceptibility
of those persons exposed. It is therefore more an exercise in
probability and chance, rather than fact - regardless of how many
"scientists" and "experts" are thrown at the problem. Also, it DOES NOT
consider the human health effects of past exposures.
A reading of the IICPH's Review of the CanTox risk assessment for
Frederick St.(Sierra Club, February, 1999,) should have drawn the
attention of those persons in decision-making positions in Nova Scotia
Environment, Health and Labour to the fact that a Health Risk Assessment
is an exercise in probability, requiring many assumptions to be made
regarding toxics sources and human receptor dosages. This is NOT, nor
can it ever be, a definitive statement of human health outcome due to
exposure. Nova Scotia government personnel, instead of making meaningful
community health decisions, seem to prefer the mass retreat to behind
the barricades of the "health risk assessment," - which they erroneously
believe is the "answer" to all community toxic exposure problems. This
is unrealistic, uninformed, unprofessional and irresponsible.
Those Government of Nova Scotia employees connected in ANY way with
community toxic exposures should be given time off to attend an
intensive course in health risk assessment methodologies, including the
complex statistical foundation, and uncertainties, inherent in the whole
process. They would then understand the uncertainties which must arise
from the many assumptions which have to be made. They may ten also
understand that the main objective of a health risk assessment is to
provide tools for subsequent risk management - rather than provide
esoteric and surrealistic cover for NOT carrying out proper risk
management.
Do the "authorities" understand that the new Shopping Centre may attract
no customers, ..............?
Do they undertsand that workers at the site can refuse to work as their
right under the
Regulations of the Occupational Health and Safety Act................. ?
Having said this, it continues to be beyond belief that anyone
knowledgeable
about the hydro-geographical extent and distribution of toxic chemicals
in the Muggah Creek area could, at this point, even think of wasting
more time and money on more health risk assessments. The health risk
assessment is NOT the tool for the job here.
Why doesn't the Government of Nova Scotia just establish the separation
zone as suggested, and get on with turning the whole contaminated mess
into an international centre for toxics clean-up research.
--
Roger Dixon, B.Sc.(Tech), MPH, CIH, P.Eng
Certified Industrial Hygienist (American Board of Industrial Hygiene)
Consultant - Environment, Safety & Health
258 Wynford Place
Oakville, Ontario L6L 5T3, Canada
Tel (905) 469-0948
Fax (905) 469-9938
