Commercial Formulation of Chlorpyrifos Alters Neurological Behaviors and Fertility.

Pesticides are known to result in toxic insult. We aimed to evaluate Judo 40, the commercial formulation of chlorpyrifos on the neurological activities, fertility, and hormone levels of male rats. Male Wistar rats were treated orally with 1 mL of 20 or 50 mg/kg Judo 40. The doses were administered four times, twice a day. Sexual and exploratory behavior indices, fertility indices, serum androgen levels, blood acetylcholinesterase (BChE) levels, and neurological and muscular effects were evaluated. Serum testosterone and luteinizing hormone were significantly reduced in the rats receiving 50 mg/kg Judo 40. A reduction in viable implantation sites and live pups born were evident in the female rats mated with the male rats treated with the highest dose. Similarly, in the rats treated with the highest dose of Judo 40, a significant reduction in plasma BChE enzyme was observed. According to the results, prolonged Judo 40 exposure can cause impairment of the neurological alterations and sex hormones leading to impaired fertility. Therefore, chemical handlers should be educated on protection and risk minimization.

Use and Avoidance of Pesticides as Responses by Farmers to change Impacts in Rice Ecosystems of Southern Sri Lanka.

Since the beginning of the millennium, pesticide use has increased dramatically across Asia. However, it is still unclear what drives pesticide use among low-income farmers. We surveyed 275 farmers to investigate their decisions to apply or avoid pesticides on rice farms in southern Sri Lanka. Based on the information from the survey, we applied the Drivers-Pressures-State-Impacts-Responses framework to assess farmers' decisions as 'Responses' to changes in the rice ecosystem. Organic farmers mainly planted traditional varieties (64-77%) that they perceived as resistant to environmental stresses, including insect herbivores. Pesticide users, including integrated pest management farmers, and insecticide-free farmers (without insecticide use for ≥5 years) mainly planted modern rice varieties. There were no significant differences in reported rice yields among farmers using different management practices. However, fewer organic and insecticide-free farmers reported insect pests, particularly planthoppers, as a production constraint. Insecticide use by farmers was mainly an adaptive response to perceived risks of pest damage to high-yielding varieties. But farmers' responses were largely unsupported by any previous experience, suggesting that an increased availability and marketing of agrochemicals, and pressures to modernize production have influenced their decisions to use insecticides. Organic and insecticide-free farming practices were mainly restorative responses to perceived health risks associated with agrochemicals. We suggest that attention could be placed on promoting 'pesticide-free' or 'insecticide-free' farming through certification schemes as a viable option to break the lock-in of pesticide use on rice farms in the region and to provide additional product choices for rice consumers.

Geochemical and mineralogical characteristics of elephant geophagic soils in Udawalawe National Park, Sri Lanka.

Geophagy or deliberate ingestion of soils was observed among Asian elephants (Elephas maximus) in the Udawalwe National Park, Sri Lanka, for several years. The geochemical and mineralogical composition of the clayey soil layers which are purposefully selected and eaten by elephants in the park were studied, in order to identify the possible reasons for elephant geophagy. The concentrations of major and trace elements were determined by means of X-ray fluorescence spectrometry in 21 soil samples from eight geophagic sites and six soil samples collected from four non-geophagic sites. The mineralogical composition of selected soil samples was investigated using X-ray diffractometry (XRD). These geochemical analyses revealed that geophagic soils in the study areas are deeply weathered and that most of the elements are leached from the soil layers under extreme weathering conditions. The XRD data showed that the soils of the area consisted mainly quartz, feldspar, and the clay minerals kaolinite, Fe-rich illite, and smectite. Although no significant geochemical differences were identified between geophagic and non-geophagic soils, a clear difference was observed in their clay mineralogical content. Soils eaten by elephants are richer in kaolinite and illite than non-geophagic soils, which contain a higher amount of smectite. It is suggested that elephants in Udawalawe National Park ingest soils mainly not to supplement the mineral contents of their forage but to detoxify unpalatable compounds in their diet.