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Environmental factors have been shown to contribute to the incidence of Parkinson's disease (PD). Pesticides, which represent one of the primary classes of environmental agents associated with PD, share the common feature of being intentionally released into the environment to control or eliminate pests. Pesticides consist of multiple classes and subclasses of insecticides, herbicides, rodenticides, fungicides, fumigants and others and exhibit a vast array of chemically diverse structures. In this review we examine the evidence regarding the ability of each of the major pesticide subclasses to increase the incidence of PD. We propose that, from a toxicological perspective, it would be beneficial to identify specific subclasses, common structural features and the propensity for widespread human exposure when considering the potential role in PD, rather than using the overly broad term of 'pesticides' to describe this diverse group of chemicals. Furthermore, these chemicals and their environmentally relevant combinations should be evaluated for their ability to promote or accelerate PD and not merely for being singular causative agents.

BACKGROUND: Human health anomalies have been associated with pesticide exposure for people living in rural landscapes in the northern Great Plains of North America. OBJECTIVE: The objective of this study was to investigate the occurrence of 45 pesticides in drinking water from reservoirs in this area that received water primarily from snowmelt and rainfall runoff from agricultural crop lands. METHODS: Water from 15 reservoirs was sampled frequently during the spring pesticide application period (early May to mid-August) and less frequently for the remainder of the year. Drinking water was sampled in early July. Sample extracts were analyzed for pesticide content using mass spectrometric detection. RESULTS: We detected two insecticides and 27 herbicides in reservoir water. Consistent detection of a subset of 7 herbicides suggested that atmospheric deposition, either directly or in rain, was the principal pathway from fields to the reservoirs. However, the highest concentrations and number of herbicides in drinking water were associated with runoff from a localized 133-mm rainfall over 15 days toward the end of spring herbicide application. Water treatment removed from 14 to 86% of individual herbicides. Drinking water contained 3-15 herbicides (average, 6.4). CONCLUSIONS: We estimated the mean annual calculated concentration of herbicides in drinking water to be 75 ng/L (2,4-dichlorophenoxy)acetic acid, 31 ng/L (2-chloro-4-methylphenoxy)acetic acid, 24 ng/L clopyralid, 11 ng/L dichlorprop, 4 ng/L dicamba, 3 ng/L mecoprop, and 1 ng/L bromoxynil. The maximum total concentration of herbicides in drinking water was 2,423 ng/L. For the seven herbicides with established drinking water guidelines, all concentrations of the individual chemicals were well below their respective guideline. However, guidelines have not been established for the majority of the herbicides found in drinking water or for mixtures of pesticides. KEY WORDS: drinking water, northern Great Plains, pesticides, reservoirs, water treatment. Environ Health Perspect 115:1183-1191 (2007). doi:10.1289/ehp.9435 available via http://dx.doi.org/ [Online 15 May 2007], In agricultural landscapes, rural and municipal residents can be exposed to agricultural pesticides either directly during crop applications or indirectly in air, water, or food. In the northern Great Plains [...]

Byline: B. Sechser (1), J. Freuler (2) Abstract: The side effects of the neonicotinyl compound thiamethoxam on the brood of bumble bees (Bombus terrestris L.) were investigated on tomatoes in plastic tunnels and glasshouses. Preceeding trials had revealed a strong contact and stomach activity of the compound by foliar application. A decisive improvement was obtained by replacing the foliar by drip irrigation of thiamethoxam at rates between 150 and 161g ai/ha. The mortality figures of all bumble bee stages dropped to the level in the untreated control. No dead bumble bees were found in the thiamethoxam treated tunnels/glasshouses on the ground. Thiamethoxam could be rated as being harmless to bumble bees with a single application through the irrigation system. No spilling of this compound during the application should occur to avoid intoxication of adult bumble bees by oral uptake or contact contamination during the cleaning process. If multiple applications via the irrigation system or under any hydroponic growing conditions is considered, further sequential testing of this mode of use is recommended. Author Affiliation: (1) Bodenacker 73, CH-3065, Bolligen, Switzerland (2) Swiss Federal Research Station for Plant Production, CH-1260, Nyon 1, Switzerland (1) c/o Fr. C. Kolb, Syngenta Crop Protection AG, WRO 1004.7.30, Schwarzwaldallee 215, P.O. Box, CH-4002, Basel, Switzerland

A body of research has shown that exposures to a number of chemicals can affect men's reproductive health as well the survival of male fetuses. Now a study in the [...]

doi:10.1289/ehp.11010 Roberts et al. (2007) recently reported on the results of their investigation into the relationship between agricultural pesticides and autism spectrum disorders (ASD) and found an association between organochlorines [...]