title: A survey of urinary hippuric acid and subjective symptoms among occupational low toluene exposed workers.
abstract: Biological monitoring of toluene exposure by urinary hippuric acid determination and a subjective symptom survey by self-administered questionnaire were performed in 20 workers at low toluene exposure in factories to evaluate the health hazard including dysfunction of nervous system. Environmental monitoring was carried out using toluene gas detection tubes. Urine samples were collected three times a day in order to measure hippuric acid: first before the commencement of work, then at the end of forenoon work, and lastly at the end of afternoon work. Toluene vapor concentrations of throughout the workday ranged from 15.3 to 31.4 ppm. The urinary hippuric acid concentrations correlated with the toluene concentrations of ambient air (r = 0.58, p = 0.01). The subjective symptoms increased in close association with the exposure to toluene; the prevalence rate of subjective symptoms "during work" in the exposed group was 15 times higher than the rate of the non-exposed group (p < 0.0001). The prevalence rate of subjective symptoms "off-work" in the exposed group was 2.4 times higher than the rate of the non-exposed group (p < 0.0001), and also the prevalence rate of "nineteen symptoms off-work which are apparently related to central nervous system (CNS) and autonomic nervous system (ANS)" in the exposed group was 1.8 times higher than the rate of the non-exposed group (p < 0.05). From these results, these subjective symptoms, which have been believed to be complained in high organic solvent exposure should be reassessed and reconsidered in evaluating the nervous system dysfunction and local irritation in relatively low toluene exposed workers.
authors.affiliation: Department of Hygiene and Preventive Medicine, Fukushima Medical University School of Medicine, Fukushima, Japan. ktanaka@fmu.ac.jp
authors.forename: Kazuko
authors.initials: K
authors.lastname: Tanaka
authors.forename: Takafumi
authors.initials: T
authors.lastname: Maeda
authors.forename: Toshio
authors.initials: T
authors.lastname: Kobayashi
authors.forename: Masatoshi
authors.initials: M
authors.lastname: Tanaka
authors.forename: Tetsuhito
authors.initials: T
authors.lastname: Fukushima
mesh_terms: D000328:Adult; D000395:Air Pollutants, Occupational / Q000009:adverse effects* / Q000032:analysis; D004784:Environmental Monitoring; D005260:Female; D006626:Hippurates / Q000652:urine*; D006801:Humans; D007564:Japan; D008297:Male; D008875:Middle Aged; D009422:Nervous System Diseases / Q000139:chemically induced / Q000652:urine; D009784:Occupational Diseases / Q000139:chemically induced / Q000652:urine; D016273:Occupational Exposure; D011795:Surveys and Questionnaires; D014050:Toluene / Q000009:adverse effects* / Q000032:analysis
chemical_list: D000395:Air Pollutants, Occupational; D006626:Hippurates; D014050:Toluene; C030514:hippuric acid