Biomonitoring and whole body cotton dosimetry to estimate potential human dermal exposure to semivolatile chemicals

Current methods of estimating absorbed dosage (AD) of chemicals were evalua ted to determine residue transfer from a carpet treated with chlorpyrifos ( CP) to humans who performed a structured exercise routine. To determine the dislodgeability of residue, a California Department of Food and Agricultur e (CDFA) roller was applied to a flat cotton cloth upon a treated carpet. L evels ranged from 0.06 to 0.99 mu g CP/cm(2). Cotton whole body dosimeters (WBD) were also used to assess residue transfer. The dosimeters retained 1. 5 to 38 mg CP/person. Urine biomonitoring (3 days) for 3,5,6-trichloro-2-py ridinol (TCP) of persons who wore only swimsuits revealed a mean AD of 176 mu g CP equivalents/person. The results show that the AD depends on the ext ent of contact transfer and dermal absorption of the residue. Default expos ure assessments based upon environmental levels of chemicals and hypothetic al transport pathways predict excessive exposure. The cotton WBD retains ch emical residues and may be effectively used to predict dermal dose under ex perimental conditions.