An Israeli study has found a high incidence of Parkinson’s disease among those living in Jewish agricultural communities near the Gaza border.
According to the study, the percentage of Parkinson’s sufferers is 37 percent to 54 percent higher than the average in the Negev. The researchers, neurologists from the Soroka Medical Center in Be’er Sheva, believe that the reason for the high morbidity is exposure to pesticides, which are used in the cultivated fields.
Parkinson’s is a gradual degenerative disease that affects the central nervous system, and is characterized by motor disturbances such as a slowing and decline in movement, muscle rigidity, involuntary tremors, problems of balance and more. The source of the illness is defective functioning in the parts of the brain responsible for motor control. There is no certainty about the causes, but the prevailing assumption is that they are genetic as well as environmental.
This is not the first time that a connection has been made between exposure to pesticides and a higher incidence of Parkinson’s.
“Our study joins studies that reinforce the environmental connection to Parkinson’s, and we believe there’s a connection between agricultural pesticides and the disease,” says Dr. Yair Zlotnik of the Soroka neurology department, one of the researchers.
The present study uses the database of Parkinson’s patients in the area of the Gaza envelope who are insured by Clalit Health Services (which insures 70 percent of the Negev population), and included 3,792 patients, Jews and Bedouin, some living in cities or communal settlements and some in agricultural communities and in the Bedouin diaspora. The information was examined relative to the proximity of the patients to cultivated fields in their area of residence.
There were dramatic differences in the frequency of the disease – among Jews the percentage of Parkinson’s sufferers is 37 percent higher than the average in the Negev in places with few cultivated fields. In communities with many cultivated fields the morbidity is 54 percent higher than the regional average. In the Bedouin diaspora the frequency is 53 percent lower than the average in the Negev as a whole, and 71 percent lower than the average in the permanent communities that are not surrounded by cultivated fields.
“The study enabled us to see clearly the differences between the genetic and environmental contribution,” explained Zlotnik. “We know that in the Ashkenazi Jewish population [originating in Europe] there are a number of genes that increase the risk of the disease, and morbidity among Ashkenazim is in fact higher in general. Among the Bedouin, who have no genetic tendency for the disease, we discovered that those living in the Bedouin diaspora near agricultural fields suffer more from Parkinson’s than those living in permanent communities.”
The study is actually a continuation of one conducted in Soroka in the late 1990s. At the time they examined three kibbutzim in the Gaza envelope area and found a high incidence. Due to improved technology and documentation since then the present study is more precise and more comprehensive.
But still the study has shortcomings – it doesn’t measure morbidity in connection with specific types of pesticides. “We assume that the morbidity that we’re seeing today is a result of degenerative processes that began 20-30 years ago, and it’s hard to know today exactly to which substances they were exposed,” says Zlotnik.
Nor did the researchers take into account the residential history of the patients in the area, or in other words, for how long they were exposed to the pesticides in the Gaza area. “There’s still a lot to study regarding this connection,” explains Zlotnik. “We think that there’s room for follow-up studies, maybe together with the Environmental Protection Ministry, in order to study the nature of the exposure and its effects in greater depth.”