More Study Needed on POPs-Diabetes Link
Cambridge scientists
are advocating additional research into the little understood links
between environmental pollution and type 2 diabetes.
In the most recent edition of the Lancet, Drs. Oliver Jones
and Julian Griffin highlight the need to research the possible link
between persistent organic pollutants (POPs, a group which includes
many pesticides) and insulin resistance, which can lead to adult-onset
diabetes.
In their commentary, Jones and Griffin cite peer reviewed research including that of Dr. D. Lee, et al,
which demonstrated a very strong relationship between the levels of
POPs in blood, particularly organochlorine compounds, and the risk of
type 2 diabetes.
“Of course correlation does not automatically imply causation,” says
Jones. "But if there is indeed a link, the health implications could be
tremendous. At present, there is very limited information. Research
into adult-onset diabetes currently focuses on genetics and obesity;
there has been almost no consideration for the possible influence of
environmental factors such as pollution.”
Interestingly, in the Lee study an association between obesity and
diabetes was absent in people with low concentrations of POPs in their
blood. In other words, individuals were more at risk of diabetes if
they were thin with high levels of POPs in their blood than if they
were overweight but with low levels of POPs.
Jones said: "I think research should be carried out to first test
the hypothesis that POPs exposure can cause diabetes, perhaps using
cell or tissue cultures, so we know for sure if this can occur.
Assuming POPs can have this effect, the next step would be to try and
develop a method of treatment for those people who might be affected.”
POPs came into prominence as effective pesticides with the
introduction of DDT in the 1940s. However, many of these chemicals,
including DDT, fell out of favor after they were blamed for the
declining number of wild birds and other animals (brought to the
public's attention in Rachel Carson's Silent Spring) and the
possible negative human health effects. As the compounds biodegrade
slowly, they continue to find their way into the food chain and
ultimately into the blood streams of individuals even though many of
these toxins were banned many years ago. Additionally, these compounds
can persist in body fat for very long periods of time following
exposure.