From September 9, 2005
Environmental
Toxins Linked to Parkinson's
(Beyond Pesticides, September 9, 2005)
Exposure to certain chemicals found in pesticides and herbicides may
increase the risk of Parkinson's disease in people with a family history
of the disease, according to a new study. Researchers say the findings
support evidence of a possible link between environmental toxins and
Parkinson's disease and may help explain why some people with genetic
risk factors for the disease get it while others do not.
Parkinson's disease is a common neurological disorder that can occur
randomly or as the result of inherited gene mutations. Numerous past
studies have found connections between Parkinson’s disease and
pesticides and other environmental toxins, but this study is the first
to explain how genetic factors affect the connection. Read more about
the evidence for pesticide’s link to Parkinson’s in Beyond
Pesticides Daily News archives.
In the study,
which appears in Current Biology, researchers looked at fruit flies
lacking both forms of a gene that is associated with the inherited form
of Parkinson's disease. These specially bred fruit flies became extremely
sensitive to the herbicide paraquat and the insecticide rotenone and
died after exposure.
Researchers based their study on previous findings that show exposure
to environmental toxins may raise the risk of developing the disease
by increasing the rate of oxidative stress. Oxidative stress is related
to the body's ability to eliminate free radicals in the body and can
result in cell damage within the body.
In the study, researchers showed that flies lacking forms of the DJ-1
gene were normal under standard conditions. But when they were exposed
to high doses of the herbicide paraquat and insecticide rotenone, which
have previously been linked to Parkinson's disease, the flies suffered
from extreme oxidative stress and died.
Researchers say these findings suggest that a loss of DJ-1 gene function
increases sensitivity to chemicals that cause oxidative stress. Together,
researchers say the results shed new light on the biological connections
between the inherited and sporadic forms of Parkinson's disease and
may lead to more effective treatments.
TAKE ACTION: Write to U.S.EPA Acting Administrator Stephen
Johnson to let him know that they have a duty to alert the public
to the scientific findings (laboratory and epidemiologic) that link
pesticides with Parkinson's disease. In addition, urge these EPA officials
to initiate an urgent and expedited review of pesticides' link to Parkinson's.