RECOVERY OF SOME COMMON SOLVENTS FROM AN ADHESIVE COMMERCIAL SKIN ADSORPTION PAD BY THERMAL-DESORPTION GAS-CHROMATOGRAPHY

A thermal desorption-gas chromatography (GC) system was developed for use with commercial adhesive plasters used for monitoring exposure of hands to common solvents, The efficiency of solvent adsorption on the activated carbon pads located on the plasters was determined for aceto ne, trichloroethylene, D-limonene, methanol, ethyl methyl ketone, tolu ene, tetrachloroethylene and m-xylene, The degree of solvent recovery for the system was also investigated-for each solvent, as was its sens itivity and reproducibility. All solvents exhibited > 90% adsorption o n the pads at spiking levels of 100-200 ng for each solvent, except fo r m-xylene and d-limonene, Solvent recovery was dependent on the volat ility of the solvent at spiking volumes of about 1 mu l per pad with s olvents with boiling points above 110 degrees C showing recoveries of <75%, Increasing primary desorption times and temperatures increased t hese values, The precision was good with RSD <5% for all solvents over the range 0.5-5.0 mu l of applied solvent, It was possible to detect 15-60 ng of each solvent component; within solvent mixtures on the pad s with the exception-of D-limonene. It is concluded that all solvents tested except D-limonene can be determined on the pads under the condi tions for thermal desorption-GC analysis described, The pads were used under protective gloves with six workers using xylene isomers as solv ent in-the workplace, when apparent solvent breakthrough through their gloves was observed.