Health hazards fall into
- acute effects: health
effects from exposure to large amounts of pesticides in a small time
- chronic effects: health
effects from long-term exposure to herbicides.
The acute effects of herbicides include, but are not
limited to poisoning. Lack of medical attention following exposure
in large quantities can be fatal.
Symptoms may include cramping, vomiting, and headaches (Masiunas
- Cancer: The link between herbicides and cancer
is still a debated topic. Some
research shows significant results for a link, while others discard
the idea. One study showed an increase in cancer mortality in four
northern wheat-producing states.
The study compared rare cancer cases in different counties
that are above and below the median of wheat acreage per county.
The findings showed increased mortality for cancer of the nose
and eye in men and women, brain and leukemia for boys and girls, and
all cancers in boys (Schreinemachers, 2000).
Another study, conducted in North Carolina, suggests that children
under14 have four times the normal risk of contracting cancer, namely
soft tissue sarcoma, if their gardens are treated with pesticides
or herbicides (“Garden,” 1995).
Other studies linking herbicides to child cancer include one
in which agent orange causes a form of leukemia in Vietnam veteran’s
children (“Agent Orange Linked” 2001).
Moreover, three Swedish case-control studies suggest that exposure
to 2,4,5-T and 2,4-D and similar compounds results in a six-fold increase
in risk for soft tissue sarcoma. Similar survey conducted in New Zealand,
however, found these associations weak (Coggon, 1987).
- Diabetes: A report, sponsored by the US Department
of Veteran Affairs, claims that there is suggestive evidence of a
link between exposure to dioxin (a chemical found in Agent Orange
and other herbicides) and the development of Type 2 diabetes. Although any increased danger from dioxin
exposure appears to be small, research findings linking dioxin with
Type 2 diabetes have now accumulated over a long period of time ("Agent
Orange Exposure," 2001).
Three herbicides, paraquat, dinoseb, and 2,4-D, have been shown
to affect mitochondrial bioenergetics.
Each herbicide causes the effects by different mechanisms. Their effects lead to the disruption
of cellular energetic and metabolism (Palmeira, 1999).
- Infertility: Scientists have observed reduced litter
size in female lab mice exposed to small amounts of common herbicides. The 10% to 20% litter reduction may
be a result of herbicides interference with hormones that control
uterus implantation (Withgott, 2002).
Another study compares the occupation of patients attending
a tertiary referral center.
The study found that farmers were over-represented compared
with the general population. Farmers also demonstrated a significantly
higher proportion of reduced sperm counts and severely reduced sperm
concentrations in comparison to the entire infertile group of men. The study further showed that significantly
more farmers have maldescended testis than other groups (Kenkel et