Organophosphate (OP) compounds are extensively used as pesticides to increase agricultural production and for applications in and around the home. It is estimated that nearly 2.8 million tons of pesticides are used each year worldwide (Ecobichon, 2001). South Africa is considered one of the largest consumers of pesticides in sub-Saharan Africa (Zhang et al., 2011), with the agricultural sector accounting for a large percentage of pesticide sales (Naidoo and Buckley, 2003). However household pesticides used for the control of insects and rodents is commonly practiced in South Africa (Tolosana et al., 2009), thus resulting in continued pesticide exposure.
OPs produce multiple neurotoxic effects. The most recognised mechanism of action is acetylcholine disruption that occurs by inhibiting acetylcholinesterase enzyme, resulting in accumulation of synaptic acetylcholine and altered cholinergic signalling. However, OP effects can occur in the absence of acetylcholinesterase inhibition (Kamel and Hoppin, 2004). Non-cholinergic mechanisms include oxidative stress processes (Moretto and Colosio, 2011), altered cell signalling, inflammation and cytokine release (Banks and Lein, 2012) and alteration of the serotoninergic and dopaminergic system (reviewed by). OP and depression Deficiencies in the serotonergic system are frequently associated with emotional disorders such as depression and anxiety.
Recent reviews have suggested that OP pesticides may contribute to depression, impulsivity and suicide in agricultural populations especially among pesticide applicators (Kamel and Hoppin, 2004, London et al., 2005, Beseler et al., 2006, Beseler and Stallones, 2008, London et al., 2012, Freire and Koifman, 2013) and their spouses (Beseler et al., 2006). Increased aggressive behaviour showed increased hostility levels among banana workers who were poisoned (weselling 2010) These studies have shown an association between urinary DAPs and mental health outcome. Hair samples have shown…. Pesticide-exposed populations therefore remain an area of increasing public health concern.
The prevalence of suicide Suicide is a public health concern, especially in developing countries where poverty, deaths accounts for ##. induce neuronal cell death, cause alterations of morphology of cells in the nervous system, impairment of the blood brain barrier.
Pesticide-exposed populations remain an area of increasing public health concern. There has been considerable research conducted on the effects of OP pesticides on mental health in agricultural and rural communities that are exposed to high levels of pesticides. Less information is available in the general population who are exposed to low levels of pesticides, where domestic and garden pesticide use are primarily the source of pesticide exposure. The aim of the study therefore is to (1) investigate the association between OP exposure as assessed by hair DAP metabolites and reported environmental and occupational history and attempted suicide in adults living in Cape Town, South Africa and (2) to examine the association between OP exposure and neurobehavioural measures.