title: Assessment of dermal exposure to benzene and toluene in shoe manufacturing by activated carbon cloth patches.
abstract: OBJECTIVE
  The aim of this investigation was to use activated carbon cloth (ACC) patches to study the probability and extent of dermal exposure to benzene and toluene in a shoe factory.
  
  
  METHODS
  Inhalation and dermal exposure loading were measured simultaneously in 70 subjects on multiple days resulting in 113 observations. Dermal exposure loading was assessed by ACC patches attached to likely exposed skin areas (e.g. the palm of the hand and abdomen). A control patch at the chest and an organic vapor monitor (OVM) were used to adjust the hand and abdomen patches for the contribution from the air through passive absorption of benzene and toluene on the ACC patches. Systemic exposure was assessed by quantification of unmetabolized benzene (UBz) and toluene (UTol) in urine.
  
  
  RESULTS
  Mean air concentrations for the study population were 1.5 and 7.5 ppm for benzene and toluene, respectively. Iterative regression analyses between the control patch, OVM and the dermal patches showed that only a small proportion of the ACC patches at the hand had likely benzene (n = 4; mean 133 microg cm(-2) h(-1)) or toluene (n = 5; mean 256 microg cm(-2) h(-1)) contamination. Positive patches were exclusively observed among subjects performing the task of gluing. Significant dermal exposure loading to the abdomen was detected only for toluene (n = 2; mean 235 microg cm(-2) h(-1)). No relation was found between having a positive hand or abdomen ACC patch and UBz or UTol levels. In contrast a strong association was found between air levels of benzene (p = 0.0016) and toluene (p < 0.0001) and their respective urinary levels.
  
  
  CONCLUSIONS
  ACC patches are shown to be a useful technique for quantifying the probability of dermal exposure to organic solvents and to provide estimates of the potential contribution of the dermal pathway to systemic exposure. Using ACC patches we show that dermal exposure to benzene and toluene in a shoe manufacturing factory is probably rare, and when it occurred exposures were relatively low and did not significantly contribute to systemic exposure.
authors.affiliation: Occupational and Environmental Epidemiology Branch, Division of Cancer Epidemiology and Genetics, National Cancer Institute, NIH, DHHS, Rockville, MD 20892, USA. R.Vermeulen@iras.uu.nl
authors.forename: Roel
authors.initials: R
authors.lastname: Vermeulen
authors.forename: Qing
authors.initials: Q
authors.lastname: Lan
authors.forename: Guilan
authors.initials: G
authors.lastname: Li
authors.forename: Stephen M
authors.initials: SM
authors.lastname: Rappaport
authors.forename: Sungkyoon
authors.initials: S
authors.lastname: Kim
authors.forename: Berna
authors.initials: B
authors.lastname: van Wendel de Joode
authors.forename: Min
authors.initials: M
authors.lastname: Shen
authors.forename: Xu
authors.initials: X
authors.lastname: Bohong
authors.forename: Martyn T
authors.initials: MT
authors.lastname: Smith
authors.forename: Luoping
authors.initials: L
authors.lastname: Zhang
authors.forename: Songnian
authors.initials: S
authors.lastname: Yin
authors.forename: Nathaniel
authors.initials: N
authors.lastname: Rothman
mesh_terms: D000005:Abdomen; D000395:Air Pollutants, Occupational / Q000032:analysis* / Q000652:urine; D001554:Benzene / Q000032:analysis*; D002606:Charcoal / Q000737:chemistry; D006225:Hand; D006801:Humans; D001239:Inhalation; D016273:Occupational Exposure; D010328:Patch Tests / Q000379:methods*; D012775:Shoes; D012867:Skin / Q000737:chemistry*; D013784:Textiles; D014050:Toluene / Q000032:analysis* / Q000652:urine; D014556:Urine / Q000737:chemistry
chemical_list: D000395:Air Pollutants, Occupational; D002606:Charcoal; D014050:Toluene; D001554:Benzene