title: [Investigating genetic damage of workers occupationally exposed to methotrexate].
abstract: OBJECTIVE
  To study genetic damage of workers alone occupationally exposed to methotrexate (MTX) with three end-points.
  
  
  METHODS
  The blood samples from 21 workers exposed to MTX and 21 controls were detected with micronucleus test, comet assay, hprt gene mutation test and TCR gene mutation test.
  
  
  RESULTS
  The mean micronuclei rate (MNR) and mean micronucleated cells rate (MCR) in 21 workers were 10.10 per thousand +/- 0.95 per thousand and 8.05 per thousand +/- 0.75 per thousand, respectively, which were significantly higher than those (5.48 per thousand +/- 0.82 per thousand and 4.38 per thousand +/- 0.58 per thousand) in control (P < 0.01). The mean tail length (MTL) of 21 workers and 21 controls were (1.30 +/- 0.06) microm and (0.07 +/- 0.01) microm, respectively, there was significant difference between workers and controls (P < 0.01). But the difference between workers and controls for mean tail moment (MTM) was not significant (P > 0.05). The average mutation frequency (Mf-hprt) of hprt and (Mf-TCR) of TCR in workers were 1.00 per thousand +/- 0.02 per thousand and (6.87 +/- 0.52) x 10(-4), respectively, which were significantly higher than those [0.86 per thousand +/- 0.01 per thousand and (1.67 +/- 0.14) x 10(-4)] in control (P < 0.01).
  
  
  CONCLUSIONS
  The genetic damage to some extent appeared in workers occupationally exposed to methotrexate.
authors.affiliation: Istitute of Occupational and Enviromental Health, Medical College, Zhejiang University, Hangzhou 310006, China.
authors.forename: Hong-ping
authors.initials: HP
authors.lastname: Deng
authors.forename: Yun-tao
authors.initials: YT
authors.lastname: Zhang
authors.forename: Ji-liang
authors.initials: JL
authors.lastname: He
authors.forename: Mei-bian
authors.initials: MB
authors.lastname: Zhang
authors.forename: Li-fen
authors.initials: LF
authors.lastname: Jin
authors.forename: Wei
authors.initials: W
authors.lastname: Zheng
authors.forename: Jian-lin
authors.initials: JL
authors.lastname: Lou
authors.forename: Bao-hong
authors.initials: BH
authors.lastname: Wang
mesh_terms: D000328:Adult; D020552:Comet Assay; D004249:DNA Damage; D005260:Female; D006801:Humans; D007041:Hypoxanthine Phosphoribosyltransferase / Q000235:genetics; D008297:Male; D008727:Methotrexate / Q000633:toxicity*; D015162:Micronucleus Tests; D008875:Middle Aged; D009154:Mutation; D016273:Occupational Exposure
chemical_list: D007041:Hypoxanthine Phosphoribosyltransferase; D008727:Methotrexate