n-hexane polyneuropathy in Japan: a review of n-hexane poisoning and its preventive measures.
Level 5 - mechanism / opinion, no new human data
Narrative review of historical investigations, case series, and animal studies.
PubMed 8325270 · doi:10.1006/enrs.1993.1091
What was done
Narrative historical review of research and preventive measures regarding occupational n-hexane poisoning in Japan since 1963, summarizing case studies, animal experiments, and field surveys on exposure limits and biological monitoring.
What was found
Overt polyneuropathy occurred in workers exposed to time-weighted average (TWA) concentrations above 100 ppm. A threshold limit value of 40 ppm in Japan was considered sufficient to prevent subclinical peripheral nerve impairment. Urinary 2,5-hexanedione was identified as a biomarker of exposure, with approximately 2.2 mg/liter corresponding to 40 ppm TWA of n-hexane.
Why it matters
It outlines exposure thresholds for occupational solvent toxicity and establishes urinary 2,5-hexanedione as a practical biomarker for biomonitoring in industrial settings.
Limits
Narrative review design without systematic search criteria or primary data reporting. The abstract does not provide sample sizes, confidence intervals, or details of the underlying human cohorts and animal models.
Cited by
- partial Hexane is a neurotoxin used as a solvent in oil extraction, and non-petroleum workers show detectable levels of hexane in their urine from consuming solvent-extracted soy products or seed oils.