Health Problem Caused by Long-Term Organophosphorus Pesticides Exposure - Study in China

Abstract

Organophosphorus pesticides (OPs), one of the most popular classes of pesticides, are widely used all over the world especially in developing countries, such as China. There are many OPs, with thousands of trade names such as dimethoate, parathion and omethoate, most of which have been used for insect control in residential and agriculture settings. The acute toxicity of OPs are believed to be due primarily to the inhibition of acetylcholinesterase (AChE) resulting in an accumulation of acetylcholine (Ach) with a sustained overstimulation of Ach receptors in the clefts of central and peripheral neuron synapses. They can cause a progression of toxic signs, including hypersecretions, convulsions, respiratory distress, coma and death. However, the heavy usage of OPs has given rise to wide public concern on their chronic toxicity. Generally, long-tem exposure to OPs can be divided into occupational exposure and nonoccupational exposure. The former often involves farming population and workers employed in pesticide-related industries. And the latter is more for general population potentially exposed to OPs via a number of different routes including dietary, lifestyle or medicinal. China is a large country with large demand of pesticides. This means that there are much more Chinese people, both occupational and non-occupational population, whose health are under the threat of OPs exposure. The presence of common and specific metabolites of OPs in urine samples taken from the general population has demonstrated the widespread exposure to OPs in China. Moreover, workers engaged in OPs production are at high risk from OPs exposure, as confirmed by higher levels of OPs metabolites in biological samples compared to those present in individuals from non-agricultural communities. Therefore, a great deal of research has been conducted by Chinese scientists to understand the adverse effects of long-term, low-level exposure to OPs in both general and occupational population.