Long-term Neurobehavioral Effects of Mild Poisonings with Organophosphate and n-Methyl Carbamate Pesticides among Banana Workers

Universidad Nacional, Heredia, Costa Rica.
International journal of occupational and environmental health (Impact Factor: 1.37). 01/2002; 8(1):27-34. DOI: 10.1179/oeh.2002.8.1.27
Source: PubMed


Organophosphate poisoning has been associated with chronic neurobehavioral dysfunction, but no epidemiologic data exist with regard to long-term consequences from carbamate poisoning. This cross-sectional study evaluated the neurobehavioral performances of 81 banana workers who, on average 27 months earlier, had received medical attention not requiring hospitalization for mild occupational poisoning by either an organophosphate or a carbamate pesticide. These performances were compared with those of 130 banana workers who had never sought medical attention for pesticide poisoning. Poisoned subjects did less well than controls on tests measuring psychomotor and visuomotor skills, language function, and affect, the differences being significant for coding skills on the Digit-Symbol test and two tests of neuropsychiatric symptoms. These deficits, in particular a marked increase of neuropsychiatric symptoms, occurred among the organophosphate-poisoned subjects, but small deficits in performance were also seen in the carbamate-poisoned subjects. The performances of the previously poisoned subjects who had had contact with cholinesterase inhibitors within three months before testing were particularly poor. These findings in workers with mild poisoning are consistent with previous findings of persistent damage to the central nervous system from organophosphate poisoning. The possibility of persistent neurobehavioral effects associated with poisonings by nmethyl carbamate insecticides cannot be excluded. Workers with histories of poisoning may be more susceptible to neurobehavioral effects with subsequent exposures.

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Available from: Linda Rosenstock, Oct 09, 2015
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    • "Examples of populations at risk include farmers, farmworkers, pest control operators, malaria control applicators and bystanders (Ngowi et al., 2013; Kegley et al., 2003; London et al., 2002; Singer, 1999). Evidence of chronic neurotoxic effects (London, 2009; Wesseling et al., 2002), including effects on the brain, particularly those of children, are a key concern (Grandjean et al., 2006; Rohlman et al., 2005; Weiss, 2000). This situation characterized by high exposure to neurotoxins combined with vulnerable populations, requires urgent risk reduction and mitigation measures. "
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    • "Several laboratory animal and human studies have provided evidence that support the theory that OP-induced cholinergic crisis and seizures play an important role in neurological symptoms as well as changes in neurobehavioral performance that reflect learning, memory, cognitive, and psychomotor dysfunction (Drachman and Leavitt 1974; Flicker et al. 1983; Lemercier et al. 1983; Ridley et al. 1986; Rosenstock et al. 1991; Steenland et al. 1994; Wesseling et al. 2002; Hoffman et al. 2007). The neurotoxic effects from occupational and environmental chemical exposure vary along a continuum from minor subclinical deficits in sensory , memory, motor, or cognitive functioning to mental retardation and clinical disease. "
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    • "In this study, we observed behavioral depression-like symptoms and cognitive deficits in rats surviving severe POX exposure. There is evidence from the civilian population indicating that both repeated exposure to OP insecticides (Rosenstock et al., 1991; Savage et al., 1988; Wesseling et al., 2002) or a single acute exposure to nerve agents as seen in the survivors and first responders of the Tokyo subway sarin gas attack (Hood, 2001; Nishiwaki et al., 2001) can lead to chronic neurological morbidities including cognitive deficits, mood disorders and depression. Approximately 35% of soldiers deployed in the 1991 Persian Gulf War suffered from chronic multi-symptom illnesses characterized by depression and cognitive deficits (Committee on Gulf War and Health, 2010). "
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