The Impact of Pesticides - Academy Publish

Neurotoxic Disorders and Medical Management of PatientsPoisoned with Organophosphorus and CarbamatePesticidesMilan JokanovićIn this article the neurotoxic disorders appearing in patients poisoned withorganophosphorus and carbamate pesticides are reviewed. Organophosphoruscompounds cause four important neurotoxic effects in humans: the cholinergicsyndrome, the intermediate syndrome, organophosphate-induced delayedpolyneuropathy and chronic organophosphate-induced neuropsychiatric disorder.Compared to the cholinergic syndrome, that causes millions of cases of poisoningwith fatality of more than 15% each year, other disorders involve much smallernumber of patients. Carbamates have caused only cholinergic syndrome. This articleis focused on neurotoxic disorders appearing after acute and chronic exposure toorganophosphates or carbamates with emphasis on molecular mechanisms, clinicalpresentation, pathogenesis, and possibilities for prevention/medical treatment.INTRODUCTIONOrganophosphorus compounds (OPs) have been used as pesticides and developed aswarfare nerve agents such as soman, sarin, tabun, VX and others. Pesticidepoisoning results from occupational, accidental, and intentional exposure (Clark,2002). The epidemiological pattern of poisoning shows significant variation innumber of deaths and form of poisoning between developing and industrialcountries (Baker et al., 1978; Jeyaratnam, 1990; Van der Hoek et al., 1998;Eddleston, 2000; Eddleston and Phillips, 2004). According to the World HealthOrganization, about 1 million accidental and 2 million suicidal poisonings withorganophosphorus insecticides are reported per year, with more than 300000fatalities (Jeyaratnam, 1990). Medical management is difficult, with case fatalitygenerally more than 15% (Eddleston et al., 2008; Jokanović et al., 2010).OP esters cause four neurotoxic disorders in humans: the cholinergic syndrome, theintermediate syndrome, organophosphate-induced delayed polyneuropathy (OPIDP)and chronic organophosphate-induced neuropsychiatric disorder (COPIND). Thesesyndromes, arising from severe exposures, may be caused either by OP pesticides orwarfare nerve agents. Most of the cases of poisoning can be prevented by betteradministrative control, restricted access to OP pesticides, effective measures ofpersonal protection and education of OP pesticide applicators and medicalpersonnel.Carbamates (CBs) have caused only cholinergic syndrome. Serious poisonings withCBs are much less frequent when compared with OP intoxications and the chancesfor patient survival are much better. According to the 10 year experience (1997-2007) from the National Poison Control Center of the Military Medical Academy inBelgrade around 75% of carbamate poisonings were caused by a single compoundcarbaryl (Jokanović et al., 2010).The cholinergic syndromeSigns and symptoms of cholinergic syndrome occurring in acute poisoning with OPpesticides are predictable from their biochemical mechanism of action and aredirectly related to the levels of acetylcholinesterase (AChE) activity. In cases ofAcademyPublish.org - The Impact of Pesticides39