Abstract
To study the effect of occupational organophosphate exposure on neuromuscular function, 24 workers exposed to fenthion [0,0-dimethyl-0(4-methyl mercapto-3 methyl phenyl phosphorothioate], whose mean age was 31.7 years (range 22–50) and mean duration of exposure to fenthion 8.5 years (range 1–19) were subjected to detailed clinical and neurophysiological evaluation after spraying. The neurophysiological tests included motor and sensory nerve conduction velocity; F response, H reflex and electromyographic neuromuscular synapse testing. Fenthion exposure was monitored by serum acetyl cholinesterase (AchE) levels. The observations were repeated after withdrawing the workers from fenthion exposure for 3 weeks to study the reversibility of the observed changes. There was no clinical evidence of peripheral neuropathy or muscle weakness. However, peroneal motor conduction velocity (p<0.05) terminal motor latency of median (p<0.1), and peroneal nerve (p<0.05); F minimal latency and H reflex latency (p<0.01) were significantly affected. Twenty-nine per cent of workers had repetitive muscle activity. Serum AchE levels also showed significant changes (p<0.01). The clinical significance of these subtle neurophysiological changes requires further investigation and follow-up.
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Misra, U.K., Nag, D., Khan, W.A. et al. A study of nerve conduction velocity, late responses and neuromuscular synapse functions in organophosphate workers in India. Arch Toxicol 61, 496–500 (1988). https://doi.org/10.1007/BF00293697
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DOI: https://doi.org/10.1007/BF00293697