Peripheral neuropathy occupational causes

Effect of Dose and Duration of Exposure on Toxicity. No studies were located where -hexane concentration was measured in workplace air before workers became ill, so no dose-response relationship can be defined for human neurotoxicity as the result of -hexane exposure. Information on duration of exposure leading to toxicity is available from some case series reports. An occupational exposure caused sensory disturbances in the lower extremities after approximately 2 months (Herskowitz et al. 1971). A case of peripheral neuropathy after 7 months of exposure was reported among press-proofing workers in Taipei (Wang et al. 1986) a serious case resulting in quadriplegia after 8 months of exposure was reported among sandal workers in Japan (Yamamura 1969). Based on case reports, it can be estimated... 

Neurological Effects. The major public health concern regarding -hexane exposure is the potential for the development of neurotoxicity. Occupational studies have documented that human exposure to -hexane can result in a peripheral neuropathy that in severe cases can lead to paralysis (Altenkirch et al. 1977 Yamamura 1969 Wang et al. 1986). The dose-duration relationship has not been well characterized in humans, but concentrations of 500 ppm and above, and exposure for 2 months or more have been associated with human neurotoxicity. Brief exposure to extremely high concentrations of w-hexane may cause signs of narcosis in humans prostration and coma have been observed in animals exposed to a mixture of hexanes at concentrations of 70,000-80,000 ppm (Hine and Zuidema 1970). At these levels, however, explosion and fire would be the main concern. 

The human oral lethal dose is estimated between 0.5 and 5.0g/kg. Occupational exposure to nitromethane was suspected as the cause of severe peripheral neuropathy in two workers exposed for 1-2 months. ... 

Thiuram, the ethyl analog of thiram, was reported to cause peripheral neuropathy in humans (characterized by pain, numbness, and weakness in the extremities). Occupational exposure to maneb-containing fungicides caused extrapyramidal symptoms in two agricultural workers. In addition to the previously mentioned symptoms, mental confusion, drowsiness, lethargy, and flaccid paralysis were reported to occur with thiram poisoning. 

Valentini F, Agnesi R, Dal Vecchio L, et al. Does n-heptane cause peripheral neuropathy A case report in a shoemaker. Occup Med 1994 44 102-4. 

Cyanoacrylates, besides causing skin sensitization and irritation, have also been shown to cause occupational asthma and to be mutagenic. Furthermore, cyanoacrylates are suspected to be carcinogenic and to induce peripheral neuropathy. 

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