Misconceptions About the Causes of Cancer
David Bennett is the national director of the Department of Workplace Health, Safety and Environment at the Canadian Labour Congress in Ottawa.
The usual problem with the Fraser Institute’s Risk Controversy series
is that it is difficult for the educated general reader to separate the
science from the anti-government propaganda. With Misconceptions About
the Causes of Cancer, the issue is different. Nine two-line
misconceptions are addressed, but for the most part, the case of the
“misconceivers” is not spelled out. Instead, the authors plunge
straight into a refutation of the alleged misconceptions. The authors’
“antitheses” are based on a dogma that is assumed, not argued: that
all approaches to cancer control must be based on the risk assessment of
individual substances and processes.
The net result is threefold. First, a whole range of carcinogenic
hazards (e.g., trilhalomethanes in chlorinated water, asbestos,
synthetic fibres, ionizing and electromagnetic radiations, and
organochlorine pesticides)are not even mentioned. Epidemiological
studies are quoted only when they are negative. Where a positive study
is indicated, risk analysis is invoked to disprove any carcinogenic
hazard. General epidemiological estimates of occupational cancer, as a
proportion of the total, are ignored.
The second result is that alternative approaches, on which the
so-called misconceptions are based, are never given any consideration. A
third result is that when the authors put forward their own views of the
causes of cancer (e.g., diet poor in fruit and vegetables, obesity, and
lifestyle), the standards that are applied to the misconceivers are
nowhere in evidence to support the allegedly correct estimates of the
causes of cancer.
The implicit approach of the authors is that it is all right to spread
poisons over the human environment, drench workers and schoolchildren
with pesticides, and leave workplaces unregulated unless there is a good
risk analysis to vindicate regulation or restraint. This is, of course,
one possible approach. It is, mercifully, not the only one. The authors,
eminent scientists, no doubt deserve their accolades. They would also
get an A for political rhetoric. But they would flunk an elementary
course in scientific reasoning.