title: [Effects of arsenic exposure through drinking water on methylation in persons].
abstract: OBJECTIVE
  To observe the effects of arsenic exposure through drinking water on methylation in persons.
  
  
  METHODS
  The levels of inorganic arsenic (iAs), monomethylated arsenic (MMA), dimethylated arsenic (DMA) in blood and urine were detected by atomic absorption spectrophotometer with an arsenic speciation pretreatment system. Total arsenic (tAs), the first methylation index (PMI) and the second methylation index (SMI) were calculated as iAs+ MMA + DMA, (MMA+ DMA)/tAs and DMA/(MMA + DMA), respectively.
  
  
  RESULTS
  iAs, MMA, DMA, tAs and PMI in blood of exposed persons were more higher than those of control, while SMI was more lower than that of control. Significant positive correlations were found between urinary MMA and blood PMI (r = 0.419, P < 0.01), while significant negative correlations were found between urinary MMA and blood SMI (r = -0.326, P < 0.05). No significant differences were found in methylation capacity between men and women.
  
  
  CONCLUSIONS
  The arsenic methylation capacity of the persons exposed to arsenic was different from that of person non-exposed to arsenic, indicating an increase of PMI and decrease of SMI. There were no differences between sex in methylation capacity.
authors.affiliation: Department of Occupational Health, School of Public Health, China Medical University, Shenyang 110001, China. lixin@mail.cmu.edu.cn
authors.forename: Xin
authors.initials: X
authors.lastname: Li
authors.forename: Ping
authors.initials: P
authors.lastname: Hou
authors.forename: Guifan
authors.initials: G
authors.lastname: Sun
mesh_terms: D000328:Adult; D001151:Arsenic / Q000378:metabolism* / Q000633:toxicity*; D001152:Arsenicals / Q000097:blood / Q000652:urine; D019175:DNA Methylation / Q000187:drug effects; D004781:Environmental Exposure; D005260:Female; D006801:Humans; D008297:Male; D008745:Methylation; D008875:Middle Aged; D013054:Spectrophotometry, Atomic; D014874:Water Pollutants, Chemical / Q000633:toxicity*; D014881:Water Supply / Q000032:analysis*
chemical_list: D001152:Arsenicals; D014874:Water Pollutants, Chemical; C020300:monomethylarsonic acid; D001151:Arsenic