Human dosimetry studies, usefulness assessments

Humans may be exposed to 2-hexanone through contaminated air in the workplace and in the vicinity of hazardous waste sites and consumption of and dermal contact with contaminated water, especially in the vicinity of hazardous waste sites. Epidemiological studies that followed populations exposed to 2-hexanone, either in the vicinity of hazardous waste sites or in the workplace, would be useful in assessing adverse health effects in humans. In any such studies, emphasis should be placed on neurological, hematological, immunological, reproductive, and developmental effects. Similarly, human dosimetry studies of these populations would be useful in associating 2-hexanone levels with the reported effects. 

Pilot human dosimetry studies have demonstrated the usefulness of adduct measurements in exposure assessments. Higher adduct levels in heavily exposed coke oven workers compared to those with lower exposures or controls have been reported using USERIA (3 )> ELISA (36) or the P-post1abe1ing assay (41). Tobacco consumption is also positively correlated with adduct formation (49). Chemotherapeutic trials are among the best evidence that adduct levels are related to exposure because in these cases, negative controls are truly negative. The development of immunoassays for cisplatin-DNA adducts by Poirier et a1., have led to internal dosimetry estimates and predictions for prognosis (35). Levels of aflatoxin B -adducts have also been identified in human liver and breast with ELISA (40.871. in serum albumin with RIA (88) and ELISA (38)- Multiple adduct assessments are also feasible (Table III) (89). 

Several studies using either passive dosimetry or biological monitoring, or both methods, were submitted by the registrant to assess exposure to workers in the US com belt. The details of these studies are found in the USEPA Revised Human Health Risk Assessment (USEPA, 2002) and the USEPA Re-registration Eligibility Document (USEPA, 2003) on atrazine. 

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