Though not Tourette related, this study shows a link between pgarden pesticide use, an increase in Parkinson's and the effect of these compounds on dopamine levels. Tourette Syndrome is related to dopamine but there is no relationship between these two disorders and no conclusion can be made in connection with Tourette.

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Bug Killers and Parkinson's

Exposure to pesticides and herbicides in the garden, while limited, is still something to consider. Non-toxic alternatives to common pesticides are increasingly popular and a variety are on the market, either in garden shops or online.

This study supports on a larger scale what other studies have found: a correlation between pesticide and herbicide exposure and increased risk of Parkinson?s disease. Certain compounds in pesticides are believed to cause oxidative stress, cellular dysfunction, inflammation and adversely affect dopamine levels, but the relation of these mechanisms to Parkinson?s has yet to be clearly understood. Exposure to pesticides could also indicate other aspect of rural living not accounted for in the study, but there is strong evidence from previous studies to back the current findings. The study does not, however, specify the kinds of pesticides that might trigger mechanisms that lead to Parkinson?s, an objective that the researchers pose to future studies. They suggest that attempts to reduce overall exposure to pesticides, to avoid being at higher risk of the disease, might be "insufficient and impractical".

Source: Time