Conventional farming demands excessive use of chemicals in the form of synthetic fertilizers and pesticides, confirming to the norms of Green Revolution. Farmers in general, specifically in the developing countries resort to injudicious and excessive use of pesticides which is linked to the illiteracy and poverty of the rural farming community. Their overriding concern for profitable agriculture, has rendered the health of the farmers at a greater risk of developing dreadful maladies including various type of cancers, reproductive disorders, respiratory, dermal, and neuropsychological problems etc. The possible means of reducing the health risks are discussed, including the global effort to regulate the manufacture, transport and use of highly toxic pesticides. Slow and programmed transition to alternative agriculture and strengthening of farmers' knowledge on health, ecosystem and environment will prove effective.
The study investigated the extent of acute pesticide poisoning in selected agricultural communities in Indonesia, Malaysia, Sri Lanka and Thailand, as well as the contributing factors, because it is believed that this type of poisoning is a major problem in developing countries, but not in the industrialized countries, despite their extensive use of pesticides. The study confirmed the existence of this problem, which was found to be due to inadequate knowledge of the safe practices in the use of pesticides among users and to the lack of suitable protective clothing for use by agricultural workers in hot and humid climates.
Tests of pulmonary function (FVC, FEV1, FEV 1%, and single breath CO diffusion), renal function (serum creatinine and BUN), liver function (serum ALT, AST, and ALKP) and a full haematological screen were performed on 27 paraquat spraymen (mean spraying time 5.3 years; mean individual annual quantity of paraquat handled, 67.2 kg as paraquat ion) and on two control groups. One of the control groups consisted of 24 general plantation workers with minimal exposure to paraquat arising from occasional work in recently sprayed areas, and the second consisted of 23 latex factory workers with no known occupational exposure to paraquat. The results showed no significant differences as a consequence of occupational exposure to paraquat. Long-term paraquat spraying at the concentrations used produced to quantifiable harmful effects on health as measured by the indices selected for this study.
A cross sectional study was conducted to investigate the effects of pesticide exposure (organophosphate and carbamate) using nerve conductive velocity, current perception threshold (CPT). Cluster random sampling was employed to recruit 64 paddy farmers and 22 fishermen in June 2006. The duration of pesticide exposure was between (5-20) years. The CPT values were measured using Neurometer CPT/Eagle, on the index finger and the great toe with three neuroselective frequencies range (2000, 250, and 5 Hz). The results showed that at the three different frequencies, the CPT values were significantly elevated among farmers on both the medial and peroneal nerves (P < .002). The measurement of CPT can be used as a biomarker to determine and monitor the effects of organophosphate and carbamate exposure among workers who may have been exposed.
Attention has been paid to neurobehavioral effects of occupational and environmental exposures to chemicals such as pesticides, heavy metals and organic solvents. The area of research that includes neurobehavioral methods and effects in occupational and environmental health has been called "Occupational and Environmental Neurology and Behavioral Medicine." The methods, by which early changes in neurological, cognitive and behavioral function can be assessed, include neurobehavioral test battery, neurophysiological methods, questionnaires and structured interview, biochemical markers and imaging techniques. The author presents his observations of neurobehavioral and neurophysiological effects in Tokyo subway sarin poisoning cases as well as in pesticide users (tobacco farmers) in Malaysia in relation to Green Tobacco Sickness (GTS). In sarin cases, a variety effects were observed 6-8 months after exposure, suggesting delayed neurological effects. Studies on pesticide users revealed that organophosphorus and dithiocarbamate affected peripheral nerve conduction and postural balance; subjective symptoms related to GTS were also observed, indicating the effects of nicotine absorbed from wet tobacco leaves. In addition, non-neurological effects of pesticides and other chemicals are presented, in relation to genetic polymorphism and oxidative stress.