title: Lack of relationship between occupational exposure to carbon disulfide and endocrine dysfunction: a six-year cohort study of the Japanese rayon workers.
abstract: OBJECTIVE
  A six-year prospective cohort study was conducted to clarify whether the current carbon disulfide (CS2) exposure level is low enough to prevent subclinical health impairment and/or to ameliorate health effects due to previous high exposure. This paper describes the follow-up results, exposure assessment, and effects on the endocrine system.
  
  
  METHODS
  The study subjects were 432 male workers exposed to CS2 at one of the 11 rayon factories in Japan and 402 referent workers from the same factories, all of whom were examined in 1992-93. 251 CS2-exposed, 140 former-exposed and 359 referent workers participated in the follow-up survey (follow-up rate 89.9%) in 1998-99. Urinary 2-thiothiazolidine-4-carboxylic acid (TTCA) at the end of a shift as internal exposure index and the time-weighted average CS2 concentration as external exposure index were measured twice a year from 1992-1993. By using various blood indices, we evaluated effects on thyroid, hypophysis, and gonad function, as well as effects on glucose metabolism. Information on potential confounding factors, such as age, smoking and alcohol drinking, were collected and adjusted for.
  
  
  RESULTS
  When the individual exposure level was represented by arithmetic mean for TTCA and CS2 concentration, geometric means (SD) of CS2 workers were 1.61 (1.91) mg/g.crea and 5.02 (1.84) ppm, respectively. There were no exposure-related differences in glucose metabolism or any of the endocrinological indices.
  
  
  CONCLUSIONS
  No biologically significant effects of CS2 were found on endocrine function in Japanese rayon manufacturing workers when the average internal and external exposure levels were maintained below the current occupational exposure limit.
authors.affiliation: Department of Preventive Medicine and Public Health, School of Medicine, Keio University, Tokyo, Japan.
authors.forename: Toru
authors.initials: T
authors.lastname: Takebayashi
authors.forename: Yuji
authors.initials: Y
authors.lastname: Nishiwaki
authors.forename: Tetsuo
authors.initials: T
authors.lastname: Nomiyama
authors.forename: Takamoto
authors.initials: T
authors.lastname: Uemura
authors.forename: Tsuneyuki
authors.initials: T
authors.lastname: Yamauchi
authors.forename: Shigeru
authors.initials: S
authors.lastname: Tanaka
authors.forename: Haruhiko
authors.initials: H
authors.lastname: Sakurai
authors.forename: Kazuyuki
authors.initials: K
authors.lastname: Omae
mesh_terms: D000328:Adult; D000704:Analysis of Variance; D002246:Carbon Disulfide / Q000633:toxicity*; D002482:Cellulose; D002617:Chemical Industry; D016009:Chi-Square Distribution; D004703:Endocrine System / Q000187:drug effects*; D006801:Humans; D007564:Japan / Q000453:epidemiology; D008297:Male; D016273:Occupational Exposure / Q000032:analysis*; D011446:Prospective Studies; D012307:Risk Factors
chemical_list: D002482:Cellulose; C012024:rayon, purified; D002246:Carbon Disulfide