Organic debate
Compiled by Young Lee
Most consumers wonder whether the pesticide residues on produce cause cancer
and other health problems. The popular perception is that the residues must
be dangerous to health because pesticides are formulated to be highly toxic.
Certain types of insects, plants and fungi are killed, and the toxic effects
may extend to humans also.
There are also those who trust government regulation of food, and feel that
the produce we buy is safe, or believe that the amount of pesticide residue
is negligible.
Where does the truth lie? In a recent Vegetarian Times article "Pesticides:
Pro and Con," two opposing view points were presented.
The pro pesticide argument
Summary of arguments by Bruce Ames Ph.D., Director of the National Institute
of Environmental Health Sciences Centre at UC-Berkeley. He has studied naturally
occurring chemicals in foods, and has co-authored many studies on pesticides
and their cancer-causing effects.
· There is a great difference between the dose which is toxic to insects
and that which is toxic to humans, so a great safety factor exists.
· A chemical is labelled a probable carcinogen based upon high-dose rodent
tests, and those results cannot be extended to a human receiving a small dose.
· The world's leading scientific authorities on the causes of cancer
do not think that synthetic pesticide residues are a significant cause of cancer.
Inadequate fruit and vegetable consumption and smoking are more important causes.
To eliminate pesticides would increase the prices of produce and threaten public
health.
· EPA risk assessments are based upon enormous overestimates of human
exposure and carcinogenic hazard.
· Safety factors are already great, and even if child exposure to pesticides
is greater than for adults, they fall well within safe levels.
· Synthetic pesticides consumed represent only 0.01% of total ingested
pesticide. The remaining 99.99% consists of natural Ôpesticides' occurring
in food. For example, coffee contains vastly more potential carcinogens, natural
or produced by roasting, than a person is likely to ingest in the form of synthetic
pesticide residues each year. Coffee is still consumed. Therefore, natural safety
factors exist, because the dose required to cause a significant cancer risk
is so high that the risk becomes negligible.
Ames concludes by saying that there are more significant risks to be concerned
with, and that resources would be better put towards other environmental issues.
The anti pesticide argument
Summary of arguments by Richard Wiles, Director of the Agricultural Pollution
Prevention Project of the Environmental Working Group in Washington D.C. He
is co-author of "Pesticides in Children's Food."
· Phasing out the highest risk pesticides would in fact have a negligible
effect on the price of fruits and vegetables in the United States. The twelve
most consumed fruits and vegetables did not change from 1985 to 1993, despite
the EPA's cancellation of 200 pesticides during this period.
· Per capita fruit and vegetable consumption has doubled since 1975,
but cancer rates (age adjusted) have increased by 25%. The risk of cancer due
to synthetic pesticide consumption may be a greater factor than the cancer-fighting
effect of eating more produce.
· A review by the National Toxicology Program showed that 94% of chemicals
that cause cancer at high doses also cause cancer at low doses.
· Coffee is poor support for the high-dose-equals-high-risk theory, he
writes, because none of the many studies conducted has linked coffee consumption
with increases in cancer.
· Cancer is only one of the toxic effects of pesticides. The National
Academy of Sciences claims neurotoxic compounds may cause brain function loss
for children at the same dose which is deemed safe for adults.
· Pesticides are deliberately toxic to insects and cause toxic effects
in animals including cancer, nervous system damage, birth defects and interference
with immune and endocrine systems.
· Not every pesticide poses a great risk, but some of the more heavily
used are very toxic. Fifteen pesticides commonly found in food are said to be
named as probable human carcinogens by the EPA.
· Government regulations are based upon averages which do not accurately
represent individuals, particularly children and vegetarians. Furthermore, the
standards assume exposure to one pesticide at a time, an unrealistic scenario
given the multitude of pesticides used.
Wiles concludes that the health benefit of fruits and vegetables is unnecessarily
compromised by use of pesticides.