Tactile vibration thresholds after acute poisonings with organophosphate insecticides.

This study evaluated the association between acute poisoning with organophosphate pesticides (OPs) and quantitative tactile vibration thresholds. Thresholds of the dominant index fingers and big toes of 56 men hospitalized for acute poisoning with OPs were measured at hospital discharge (1-24 days after poisoning) and around seven weeks later (24-176 days after poisoning), and compared with those of controls. Thresholds of the big toes of men with severe intentional poisonings due to neuropathic OPs (metamidophos and chlorpyrifos) increased between the first and second examinations. Threshold impairment was not detected in the index finger regardless of poisoning agent or severity. The development of threshold impairment as a consequence of severe intentional poisonings with neuropathic OPs is consistent with other reports indicating that only severe OP poisonings produce sensory peripheral nerve effects.