Use of partition models in setting health guidelines for volatile organic compounds

Partition models based on the octanol-air partition coefficients and associ ated quantitative structure-activity relationships (QSARs) have been develo ped to describe the triggering of odor detection, nasal irritation, and nar cosis by common volatile organic compounds (VOCs). This study made use of t he QSARs developed by Hau and Connell (1998), Indoor Air 8, 23-33) and Hau et al. (1999a, Toxicol. Sci, 47, 93-98; 1999b, Environ. Toxicol. Pharmacol. 7, 159-167) to predict the odor thresholds, nasal pungency thresholds, and anesthetic potency in humans for four groups of VOCs, namely, alkanes, alc ohols, ketones, and acetates. The predicted outcomes with their estimated v ariability were used to evaluate the relevant guidelines on the airborne co ncentrations of these test groups. Threshold limit values (TLVs) for the te st compounds were found to be generally capable of offering adequate protec tion against nasal pungency and narcosis, except for the higher alcohols (C 6-C8) and secamyl acetate. The QSARs can also be used to set tentative guid elines for those compounds not having a TLV; values of 5 and 75 ppm were pr oposed for heptan-1-ol and dibutyl ketone respectively as examples, (C) 200 0 Academic Press.