Estimation of hand-to-mouth transfer efficiency of lead

Ann Occup Hyg. 2015 Mar;59(2):210-20. doi: 10.1093/annhyg/meu088. Epub 2014 Nov 2.


There are currently no published empirical data that characterize hand-to-mouth transfer efficiencies for metallic lead. The purpose of this study was to quantify the hand-to-mouth transfer efficiency of lead in adult volunteers (n = 6) using human saliva as a surrogate for the mouth and commercially available, 100% lead fishing weights as the source of lead for dermal loading. Study volunteers' saliva was collected and subsequently poured onto a sheet of wax paper placed on a balance scale. The volunteers handled lead fishing weights with both hands for approximately 15 s and then pressed three fingers from the right hand (test hand) into their saliva 10 times, with ~0.45kg of pressure. The left hand (control hand) was used as a comparison for dermal loading of lead and had no contact with saliva. SKC Full Disclosure® wipes were used to collect lead from the saliva and skin surfaces. Samples were analyzed using the NIOSH 7300 method, which was modified for wipes. The mean lead skin-to-saliva transfer efficiency was 24% (range: 12-34%). These data will be useful for more accurately characterizing lead hand-to-mouth transfer efficiencies and are likely to be helpful in exposure assessments or human health risk assessments.

Keywords: hand-to-mouth; lead exposure; oral exposure; saliva; transfer efficiency.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Environmental Exposure / analysis*
  • Environmental Monitoring / methods
  • Hand*
  • Humans
  • Lead* / pharmacokinetics
  • Mouth*
  • Risk Assessment
  • Skin Absorption


  • Lead