Pesticides - Avoidable Exposures

Pesticides - Avoidable Exposures (for breast cancer survivors)

Pesticides

Pesticides are used to kill crop-destroying insects, while herbicides are used to kill
undesirable plants, which means that both are intentionally toxic. Although pesticide
use has doubled every ten years since 1945, the pesticides themselves are less
successful at eradicating pests today than they were then (Crinnion 2000). Thus,
more and more of them are needed to achieve their goal.

Ongoing research continues to detect new hazards in pesticides, often at doses
once declared nontoxic by their manufacturers and the government. DDT (dichlorodiphenyl-
trichloroethane), a useful but hazardous pesticide with far-reaching health
effects, was proclaimed to be safe until its use was prohibited in 1972. DDT and
other organochlorine pesticides are still so pervasive that they have secured the
unglamorous designation persistent organic pollutants (POPs), meaning that they
persist for decades in soil, air, and water. All animals, including humans, that eat,
drink, and breathe these pollutants store them in their fat.

Connections between breast cancer and pesticide exposure have been
acknowledged for decades, although in this century the research has dramatically
accelerated, in part because the Centers for Disease Control (CDC) and other
organizations have embraced the practice of biomonitoring. According to the CDC
(2009), this technology allows scientists to test the concentration of contaminants in
people’s blood and urine in a more direct way than ever before. More than a decade
ago, some pioneering Danish researchers used biomonitoring to verify that the risk
of breast cancer was notably higher in women with high levels of the pesticide
dieldrin (Høyer et al. 1998). Dozens of other studies have been published with
similar findings. In fact, in June 2007, the journal Cancer devoted an entire
supplemental issue to “Environmental Factors in Breast Cancer,” stating (Brody et
al.): “Laboratory research has shown that numerous environmental pollutants cause
mammary gland tumors in animals; are hormonally active, specifically mimicking
estrogen, which is a breast cancer risk factor; or affect susceptibility of the
mammary gland to carcinogenesis.” While some pesticides cause harm by
impairing the immune system, others promote higher levels of dangerous estrogens
(Muñoz-de-Toro et al. 2006). Still other pesticides may influence the degree of
tumor aggressiveness (Demers et al 2000).

How relevant are animal studies to human health? According to the
World Health Organization (WHO) (2006), “All known human
carcinogens that have been studied adequately for carcinogenicity in
experimental animals have produced positive results in one or more
animal species.” What’s more, approximately 99 percent of mouse
genes are identical to those found in humans (Mouse Genome
Sequencing Consortium 2002). Accordingly, we pay close attention
to animal studies.

Guidelines for Avoiding Pesticide Exposure

The easiest way to avoid pesticides is to avoid pesticide-laden produce. The
EWG (www.ewg.org/foodnews/) has identified twelve fruits and vegetables that it
dubs “the dirty dozen,” those doused with the highest levels of pesticide (as of
2011): apples, celery, blueberries, collard greens, grapes (imported), kale,
nectarines (imported), peaches, potatoes, spinach, strawberries, and sweet bell
peppers.

You will find most organic produce labeled as such at the store. If you’re not
sure, just look at the sticker on the product; all organic produce is labeled with a
number beginning with 9. Wash all fruits and vegetables carefully, even organic
ones, to remove dirt and traces of pesticide residue.