Toxicological Review of n-Hexane (CAS No. 110-54-3) (PDF)

4.4.2.2.2. Chronic exposure ............................69
4.4.2.2.3. Reproduction/developmental studies .............70
4.4.3. Potentiation and Antagonism Studies . ...........................73
4.4.4. Mode of Action Studies ......................................82
4.4.5. Genotoxicity Studies .........................................90
4.5. SYNTHESIS AND EVALUATION OF MAJOR NONCANCER EFFECTS AND
MODE OF ACTION—ORAL AND INHALATION .....................93
4.5.1. Oral Exposure ..............................................93
4.5.2. Inhalation .................................................94
4.5.3. Mode of Action Information ..................................104
4.6. WEIGHT-OF-EVIDENCE EVALUATION AND CANCER
CHARACTERIZATION ..........................................105
4.6.1. Summary of Overall Weight-of-Evidence .......................105
4.6.2. Synthesis of Human, Animal, and Other Supporting Evidence .......106
4.7. SUSCEPTIBLE POPULATIONS AND LIFE STAGES ...................108
4.7.1. Possible Childhood Susceptibility .............................108
4.7.2. Possible Gender Differences ..................................108
5. DOSE RESPONSE ASSESSMENT...........................................110
5.1. ORAL REFERENCE DOSE .........................................110
5.2. INHALATION REFERENCE CONCENTRATION ......................111
5.2.1. Choice of Principal Study and Critical Effect — with Rationale and
Justification ..............................................111
5.2.2. Methods of Analysis ........................................116
5.2.2.1. Adjustment to a Human Equivalent Exposure Concentration . 119
5.2.3. RfC Derivation—Including Application of Uncertainty Factors (UFs) . 120
5.2.4 Previous RfC ..............................................122
5.3. CANCER ASSESSMENT ...........................................123
6. MAJOR CONCLUSIONS IN THE CHARACTERIZATION OF HAZARD AND DOSE
RESPONSE ..........................................................125
6.1. HUMAN HAZARD POTENTIAL ....................................125
6.2. DOSE RESPONSE ................................................126
6.2.1. Noncancer ................................................126
6.2.2. Cancer ...................................................127
7. REFERENCES ...........................................................128
APPENDIX A: SUMMARY OF EXTERNAL PANEL PEER REVIEW AND PUBLIC
COMMENTS AND DISPOSITION ............................................ A-1
APPENDIX B: BENCHMARK DOSE (BMD) ANALYSIS ..........................B-1
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