Association between chronic exposure to arsenic and slow nerve conduction velocity among adolescents in Taiwan.

The association between chronic exposure to arsenic and peripheral neuropathy has been controversial in previous studies, which may be due to the influence of factors, such as age, gender, chronic diseases, occupational injuries, and arsenic exposure. To clarify the question of this association, a cross-sectional study was designed. In total, 130 junior high school students aged 12-14 years were included and examined for the motor and sensory nerve conduction velocity of peripheral nerves in their right-upper and lower limbs. Concentrations of arsenic in well-water and history of drinking well-water were retrieved from a baseline database created in 1991. After adjustment for gender and height, a significant odds ratio of 2.9 (95% confidence interval [CI] 1.1-7.5) was observed for the development of slow nerve conduction velocity of the sural sensory action potential (SAP) among the study subjects with a cumulative arsenic dosage of>100.0 mg. In addition, a borderline statistical significance with odds ratio of 7.8 (95% CI 1.001-69.5) for the development of slow nerve conduction velocity of sural SAP was also observed among the study subjects who drank well-water containing arsenic concentrations of >50.0 microg/L and with a cumulative arsenic dosage of >100.0 mg. The study found that chronic exposure to arsenic might induce peripheral neuropathy. It also found that the slowing of the nerve conduction velocity of sural SAP might be an early marker of chronic arsenic neuropathy.