A new technology to measure skin absorption of vapors

Skin vapor absorption is one of the major exposure routes for some widely u sed chemicals (e.g., 2-methoxy ethanol), but a good apparatus with which ex posure can be measured is currently unavailable. In this study, a polished stainless-steel chamber-combined with computer-controlled auto-feedback sof tware and hardware, real-time gas sensors, and an auto-injection microsyrin ge-was proposed as new technology. In addition, the machines had activated- charcoal tubes and cold traps, both of which simulated the skin uptake and validated the reliability of the proposed system. The exposure concentratio ns, relative humidity, and temperature were effectively controlled at 25 +/ - 0.5 ppm (or 300 +/- 10 ppm), 80 +/- 2%, and 27.5 +/- 0.5 degrees C, respe ctively. The relative errors between the quantity of 2-methoxy ethanol coll ected in either the charcoal tubes or the cold traps and the quantity of ME injected to maintain a constant exposure were less than 5%. The authors al so used this new technology to successfully measure skin absorption of ME v apor in 6 volunteers. The authors concluded that this new technology is a d irect, continuous, noninvasive, and simple tool with which to measure skin absorption of vapors.