2019

Proctor D. Use of the latest science in cancer risk assessment for hexavalent chromium: Is it time to step away from the default regulatory approaches? Invited presentation to the International Union of Toxicology (IUTOX) / International Congress of Toxicology (ICT) meeting, Honolulu, HI, June 17, 2019.

Chappell GA, Rager JE, Wolf JC, Babic M, LeBlanc KJ, Ring CL, Harris MA, Thompson C. Similarities in the transcriptomic signatures in the duodenum of mice exposed to hexavalent chromium, captan, or folpet inform the mechanisms of chemical-induced mouse small intestine cancer. Presentation at Society of Toxicology Annual Meeting, Baltimore, MD, March 2019.

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Suh M, Wikoff D, Lipworth L, Goodman M, Fitch S, Mittal L, Ring C, Proctor D. 2019. Hexavalent chromium and stomach cancer: A systematic review and meta-analysis. Crit Rev Toxicol [ePub ahead of print]: doi: 10.1080/10408444.2019.1578730.

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Rager JE, Suh M, Chappell G, Thompson CM, Proctor DM. 2019. Review of transcriptomic responses to hexavalent chromium exposure in lung cells supports a role of epigenetic mediators in carcinogenesis. Toxicol Lett 305:40-50.

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2018

Brorby G, Ring C, Loko F, Harris MA. Characterization of hexavalent chromium and total chromium in drinking water monitoring data. Poster MP 117. Society of Environmental Toxicology and Chemistry (SETAC) North America 39th Annual Meeting, Sacramento, CA, November 4–8, 2018.

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Suh M, Wikoff D, Harvey S, Mittal L, Lipworth L, Goodman M, Goodmanson A, Ring C, Rohr A, Proctor D. Hexavalent chromium and stomach cancer: A systematic review and meta-analysis. Presented at Joint Annual Meeting of International Society of Exposure Science and International Society for Environmental Epidemiology (ISES-ISEE 2018), Ottawa, Canada, August 2018.

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Moffat I, Martinova N, Seidel C, Thompson CM. 2018. Hexavalent chromium in drinking water. Journal AWWA 110:5.

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Thompson CM, Wolf JC, Suh M, Proctor DM, HJaws LC, Harris MA. Toxicity and recovery in the duodenum of B6C3F1 mice following treatment with intestinal carcinogens; captan, folpet, and hexavalent chromium: Evidence for an adverse outcome pathway. Society of Toxicology Annual Meeting, San Antonio, TX, March 11-15, 2018.

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Thompson CM, Suh M, Proctor DM, Harris MA. Ten factors for considering the mode of action of Cr(VI)-induced intestinal tumors in rodents. Society of Toxicology Annual Meeting, San Antonio, TX, March 11-15, 2018.

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Proctor, DM. Updating the regulatory risk assessment for hexavalent chromium in California: Implications for regulatory standards. Association of Environmental Health Sciences San Diego, CA, March 20, 2018.

Proctor DM. Hexavalent chromium in drinking water: When is the science sufficient to deviate from defaults? Invited Speaker, Genetic and Environmental Toxicology Association (GETA).  Thresholds in Toxicology and Risk Assessment Fall Symposium.  Oakland, CA, November 14, 2018.

Thompson CM, Kirman CR, Hays SM, Suh M, Harvey SE, Proctor DM, Rager JE, Haws LC, Harris MA. 2018. Integration of mechanistic and pharmacokinetic information to derive oral reference dose and margin-of-exposure values for hexavalent chromium. J Appl Toxicol 38:351–365. doi: 10.1002/jat.3545.

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2017

Thompson CM, Suh M, Proctor DM, Haws LC, Harris MA. 2017. Ten factors for considering the mode of action of Cr(VI)-induced gastrointestinal tumors in rodents. Mutation Res 823:45-57.

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Thompson CM, Young RR, Dinesdurage H, Suh M, Harris MA, Rohr AC, Proctor DM. 2017. Assessment of the mutagenic potential of hexavalent chromium in the duodenum of Big Blue® rats. Toxicol Appl Pharmacol 330(1):48-52.

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Rager JE, Ring CL, Fry RC, Suh M, Proctor DM, Haws L, Harris MA, Thompson CM. 2017. High-throughput screening data interpretation in the context of in vivo transcriptomic responses to oral Cr(VI) exposure. Toxicol Sci 158(1):199–212. https://doi.org/10.1093/toxsci/kfx085

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Kirman CR, Suh M, Proctor DM, Hays SM. 2017. Improved physiologically based pharmacokinetic model for oral exposures to chromium in mice, rats, and humans to address temporal variation and sensitive populations. Toxicol Appl Pharmacol 325:9-17.

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Kirman CR, Proctor D, Suh M, Haws L, Harris M, Thompson C, Hays S. 2017. Using physiologically based pharmacokinetic modeling to address potentially sensitive subpopulations exposed to hexavalent chromium. Poster presented at Society of Toxicology Annual Meeting, March 15, Baltimore, MD.

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Rager JE, Thompson CM, Ring C, Fry RC, Harris MA. 2017. Integration of transcriptomics and high-throughput screening predictions with robust in vivo data to inform hexavalent chromium mode of action. Poster presented at Society of Toxicology Annual Meeting, March 14, Baltimore, MD.

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Thompson CM, Wolf, JC, McCoy A, Suh M, Proctor DM, Kirman CR, Haws LC, Harris MA. 2017. Comparison of toxicity and recovery in the duodenum of B6C3F1 mice following treatment with intestinal carcinogens captan, folpet, and hexavalent chromium. Toxicol Pathol 45(8):1091–1101. DOI: 10.1177/019262331yy4324.

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2016

Thompson CM, Bichteler A, Rager JE, Suh M, Proctor DM, Haws LC, Harris MA. 2016. Comparison of in vivo genotoxic and carcinogenic potency to augment mode of action analysis: Case study with hexavalent chromium. Mut Res/Genetic Toxicol Environ Mutagen 800-801:28-34.

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Wikoff D, Suh M, Harvey S, Proctor D, Beretvas T, Goodman M, Lipworth L. 2016. Systematic review and meta-analysis of occupational exposure to Cr(VI) and stomach cancer. PROSPERO 2016:CRD42016051625 Available from http://www.crd.york.ac.uk/PROSPERO/display_record.asp?ID=CRD42016051625

Thompson CM, Rager JE, Suh M, Ring CL, Proctor DM, Haws LC, Fry RC, Harris MA. 2016. Transcriptomic responses in the oral cavity of F344 rats and B6C3F1 mice following exposure to Cr(VI): Implications for risk assessment. Environ Molec Mutagen 57:706-716.

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De Flora S, Camoirano A, Micale RT, La Maestra S, Savarino V, Zentilin P, Marabotto E, Suh M, Proctor DM. 2016. Reduction of hexavalent chromium by fasted and fed human gastric fluid.  I. Chemical reduction and mitigation of mutagenicity. Toxicol Appl Pharmacol   306:113-119.

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Kirman CR, Suh M, Hays SM, Gürleyük H, Gerads R, De Flora S, Parker W, Lin S, Haws LC, Harris MA, Proctor DM. 2016. Reduction of hexavalent chromium by fasted and fed human gastric fluid.  II. Ex vivo gastric reduction modeling. Toxicol Appl Pharmacol 306:120-133.

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Cullen JM, Ward JM, Thompson CM. 2016. Re-evaluation and classification of duodenal lesions in B6C3F1 mice and F344 rats from four studies of hexavalent chromium in drinking water. Presented at the Society of Toxicology’s 55th Annual Meeting, March 13-17, New Orleans, LA.

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Thompson CM, Suh M, Proctor DM, Rager JE, Haws LC, and Harris MA. 2016. Assessment of the in vivo genotoxicity of CrVI in target organs identified in a two-year cancer bioassay. Presented at the Society of Toxicology’s 55th Annual Meeting, March 13-17, New Orleans, LA.

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Suh M, Crump K, Mittal L, Hirsch S, Valdes Salgado R, BartlettC, Van Landingham C, Rohr A, Proctor DM. 2016. Inhalation cancer risk assessment of hexavalent chromium based on updated mortality for Painesville chromate production workers. Presented at the Society of Toxicology’s 55th Annual Meeting, March 13-17, New Orleans, LA.

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Cullen JM, Ward JM, Thompson CM. 2016. Reevaluation and classification of duodenal lesions in B6C3F1 mice and F344 rats from 4 studies of hexavalent chromium in drinking water. Toxicologic Pathol 44(2):279-89.

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2015

Proctor DM, Suh M, Mittal L, Hirsch S, Salgado RV, Bartlett C, Van Landingham C, Rohr A, Crump K. 2015. Inhalation cancer risk assessment of hexavalent chromium based on updated mortality for Painesville chromate production workers. J Expo Sci Environ Epidemiol 26(2):224-231. doi: 10.1038/jes.2015.77.

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Kirman CR, Proctor DM, Suh M, Hays S. 2015. Reduction of hexavalent chromium by gastric fluids from fed and fasted individuals with applications to toxicokinetic modeling. Presented at the Society of Toxicology’s 54th Annual Meeting, March 22-26, San Diego, CA.

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Suh M, Mittal L, Hirsch S, Valdes R, Bartlett C, Rohr A, Proctor D. 2015. Lung cancer risk in chromate production workers exposed to hexavalent chromium. Presented at the Society of Toxicology’s 54th Annual Meeting, March 22-26, San Diego, CA.

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Harris MA, Thompson CM, Proctor DM, Suh M, Wolf JC, Seiter JM, Chappell MA, Haws LC. 2015. Analysis of duodenal crypt health following exposure to Cr(VI) in drinking water. Presented at the Society of Toxicology’s 54th Annual Meeting, March 22-26, San Diego, CA.

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Thompson CM, Young RR, Suh M, Dinesdurage H, Elbekai R, Harris MA, Rohr AC, Proctor DM. 2015. Hexavalent chromium does not induce mutations in the oral mucosa of transgenic Big Blue® rats following drinking water exposures at a carcinogenic dose. Presented at the Society of Toxicology’s 54th Annual Meeting, March 22-26, San Diego, CA.

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Thompson CM, Wolf JC, Elbekai RH, Paranjpe MG, Seiter JM, Chappell MA, Tappero RV, Suh M, Proctor DM, Bichteler A, Haws LC, Harris MA. 2015. Duodenal crypt health following exposure to Cr(VI): Micronucleus scoring, γ-H2AX immunostaining, and synchrotron x-ray fluorescence microscopy. Mut Res 789–790:61–66.

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Thompson CM, Young RR, Suh M, Dinesdurage HR, Elbekai RH, Harris MA, Rohr AC, Proctor DM. 2015. Assessment of the mutagenic potential of Cr(VI) in the oral mucosa of Big Blue® transgenic F344 rats. Environ Mol Mutagen 56:621-628.

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Young RR, Thompson CM, Dinesdurage HR, Elbekai RH, Suh M, Rohr AC, Proctor DM. 2015. A robust method for assessing chemically induced mutagenic effects in the oral cavity of transgenic Big Blue® rats. Environ Mol Mutagen 56:629-636.

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Thompson CM, Seiter J, Chappell MA, Tappero RV, Proctor DMSuh M, Wolf JC, Haws LC, Vitale R, Mittal L, Kirman CR, Hays SM, Harris MA. 2015. Synchrotron-based imaging of chromium and γ-H2AX immunostaining in the duodenum following repeated exposure to Cr(VI) in drinking water. Toxicol Sci 143(1): 16-25.

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2014

Kirman CR, Proctor D, Suh M, Thompson CM, Harris MA, Haws LC, Hays SM. 2014. Variation analysis of PBPK model parameters for describing the delivery of Cr(VI) to the small intestines of humans. Presented at the Society of Toxicology’s 53rd Annual Meeting, March 23-27, Phoenix, AZ.

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Proctor DM, Suh M. Campleman SL, Thompson CM. 2014. Assessment of the mode of action for hexavalent chromium-induced lung cancer following inhalation exposures. Toxicology 325:160-179.

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Hays SM, Kirman CR, Suh M, Proctor DM.  2014. Gastric reduction of hexavalent chromium [Cr(VI)] in fed and fasted human stomach samples. Presented at the Society of Toxicology’s 53rd Annual Meeting, March 23-27, Phoenix, AZ.

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Thompson CM, Kirman CR, Proctor DMHaws LCSuh M, Hays S, Hixon JG, Harris MA. 2014. A chronic oral reference dose for hexavalent chromium-induced intestinal cancer. J Appl Toxicol 34:525-536. doi: 10.1002/jat.2907.

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Suh M, Thompson C, Kirman C, Carakostas M, Haws LC, Harris M, Proctor D. 2014. High concentrations of hexavalent chromium in drinking water alter iron homeostasis in F344 rats and B6C3F1 mice. Food  Chem Toxicol 65:381-388.

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2013

O’Brien T, Ding H, Suh MThompson C, Parsons BL, Harris MA, Winkelman WA, Wolf JC, Hixon JG, Schwartz AM, Myers MB, Haws LC, Proctor DM. 2013. Assessment of K-Ras mutant frequency and micronucleus incidence in the mouse duodenum following 90-days of exposure to Cr(VI) in drinking water. Mutat Res 754:15-21. doi: 10.1016/j.mrgentox.2013.03.008

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Thompson CMProctor DMSuh MHaws LC, Kirman CR, Harris MA. 2013. Assessment of the mode of action underlying development of rodent small intestinal tumors following oral exposure to hexavalent chromium and relevance to humans. Crit Rev Toxicol 43(3): 244-274.

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Suh M, Thompson CM, Hixon JG, Harris MA, Kirman CR, Hays S Haws LC, Proctor DM. 2013. Potential involvement of oxidative stress and iron disturbance in the development of oral cavity tumors in rats exposed to hexavalent chromium. Presented at the Society of Toxicology’s 52nd Annual Meeting, March 10-14, San Antonio, TX.

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Thompson CM, Kirman CR, Proctor DM, Suh M, Hays SM, Haws LC, Harris MA. 2013. A chronic oral reference dose for hexavalent chromium. Presented at the Society of Toxicology’s 52nd Annual Meeting, March 10-14, San Antonio, TX.

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Proctor DM, Suh M, Thompson CM, Harris MA. 2013. Mode of action evaluation for hexavalent chromium-induced lung cancer. Presented at the Society of Toxicology’s 52nd Annual Meeting, March 10-14, San Antonio, TX.

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Kirman CR, Thompson CM, Proctor DM, Suh M, Haws LC, Harris MA, Hays SM. 2013. Using PBPK modeling to address diurnal variation and age differences in hexavalent chromium toxicokinetics in humans. Presented at the Society of Toxicology’s 52nd Annual Meeting, March 10-14, San Antonio, TX.

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2012

Kopec AK, Thompson CM, Kim S, Forgacs AL, Zacharewski TR. 2012. Comparative toxicogenomic analysis of oral Cr(VI) exposure effects in rat and mouse small intestinal epithelium. Toxicol Appl Pharmacol 262(2):124-138.

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Kopec AK, Kim S, Forgacs AL, Zacharewski TR, Proctor DMHarris MAHaws LCThompson CM. 2012. Genome-wide gene expression effects in B6C3F1 mouse intestinal epithelia following 7 and 90 days of exposure to hexavalent chromium in drinking water. Toxicol Appl Pharmacol 259(1):13-26.

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Proctor DMSuh M, Aylward LL, Kirman CR, Harris MAThompson CM, Gürleyük H, Gerads R, Haws LC, Hays SM. 2012. Hexavalent chromium reduction kinetics in rodent stomach contents. Chemosphere 89(5): 487-493.

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Thompson CM, Fedorov Y, Brown DD, Suh MProctor DM, Kuriakose L, Haws L, Harris MA. 2012. Assessment of Cr(VI)-induced cytotoxicity and genotoxicity using high content analysis. PLoS ONE 7(8): e42720.

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Thompson CMProctor DMSuh MHaws LC, Hebert CD, Mann JF, Shertzer HG, Hixon JG, Harris MA. 2012. Comparison of the effects of hexavalent chromium in the alimentary canal of F344 rats and B6C3F1 mice following exposure in drinking water: Implications for carcinogenic modes of action. Toxicol Sci 125(1):79-90.

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Thompson CMProctor DM, Harris MA. 2012. Duodenal GSH/GSSG ratios in mice following oral exposure to Cr(VI). Toxicol Sci 126(1):287-288.

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O’Brien TJ, Hao D, Suh M, Proctor D, Thompson CM, Harris MA, Parsons BL, Meyers MB. 2012. K-ras codon 12 GGT to GAT mutation is not elevated in the duodenum of mice subchronically exposed to hexavalent chromium in drinking water. Presented at the Society of Toxicology’s 51st Annual Meeting, March 11-15, San Francisco, CA.

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Proctor DM, Thompson CM, Suh M, Haws LC, Harris MA. 2012. Mode of action for intestinal carcinogenesis of ingested hexavalent chromium in mice. Presented at the Society of Toxicology’s 51st Annual Meeting, March 11-15, San Francisco, CA.

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2011

Thompson CM, Proctor DM, Haws LC, Hebert CD, Grimes SD, Shertzer HG, Kopec AK, Hixon JG,  Zacharewski TR, Harris MA. 2011. Investigation of the mode of action underlying the tumorigenic response induced in B6C3F1 mice exposed orally to hexavalent chromium. Toxicol Sci 123(1): 58-70.

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Thompson CM, Haws LC, Harris MA, Gatto NM, Proctor DM. 2011. Application of the U.S. EPA mode of action framework for purposes of guiding future research: A case study involving the oral carcinogenicity of hexavalent chromium. Toxicol Sci 119(1):20-40.

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Sheehan PJ, Brorby GP, Berman DW, Bogen KT, Holm SE. 2011. Chamber for testing asbestos-containing products:  Validation and testing of a re-created chrysotile-containing joint compound.  Ann Occup Hyg 55(7):797-809.

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Haws L, Proctor D, Thompson C, Harris M. 2011. Research plan to fill data gaps in the mode of action for cancer risk assessment of hexavalent chromium in drinking water. Presented at the Society of Toxicology’s 50th Annual Meeting, March 6-10, Washington, D.C.

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Kim S, Thompson CM, Kopec AK, Harris MA, Zacharewski TR. 2011. Comparison of basal and CrVI-mediated solute carrier gene expression in rodent duodenal epithelium. Presented at the Society of Toxicology’s 50th Annual Meeting, March 6-10, Washington, D.C.

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Proctor D, Haws L,Thompson C, Harris M. 2011. Use of mode of action and pharmacokinetics to inform the cancer risk assessment of ingested Cr(VI): A case study. Presented at the Society of Toxicology’s 50th Annual Meeting, March 6-10, 2011. Washington, D.C.

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Proctor D, Meek B. 2011. Using mode of action data to guide quantitative cancer risk assessment: A case study of hexavalent chromium in drinking water. Presented at the Society of Toxicology’s 50th Annual Meeting, March 6-10, Washington, D.C.

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2010

Gatto NM, Kelsh MA, Mai DH, Suh M, Proctor DM. 2010. Occupational exposure to hexavalent chromium and cancers of the gastrointestinal tract: A meta-analysis. Cancer Epidemiol 34(4):388-99.

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Urban JD, Tachovsky JA, Haws LC, Staskal DF, and Harris MA. 2010. Response to Buchanan et al.’s comment on Urban et al. “Assessment of Human Health Risks Posed by Consumption of Fish from the Lower Passaic River, New Jersey.” Sci Tot Environ 408(8):2004-2007.

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Driscoll SK, McArdle ME, Plumlee MH and Proctor D. 2010. Evaluation of hexavalent chromium in sediment pore water of the Hackensack River, New Jersey, USA. Environ Toxicol Chem 29(3):617-20.

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2008

Proctor, D. 2008Hexavalent chromium. In: Encyclopedia of Quantiative Risk Analysis and Assessment, Melnick E, Everitt B. (eds.). Wiley.

Scott PK, Proctor D. 2008. Soil suspension/dispersion modeling methods for estimating health-based soil cleanup levels of hexavalent chromium at chromite ore processing residue sites. J Air Waste Manag Assoc 58(3): 384-403.

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2004

Proctor DM, Panko JP, Liebig EW, Paustenbach, DJ. 2004. Estimating historical occupational exposure to airborne hexavalent chromium in a chromate production plant: 1940–1972. Occup Environ Hyg. 1:752–767.

Schecter, A, Papke O, Tung KC, Staskal DF, and Birnbaum L. 2004. Polybrominated diphenyl ether contamination of United States food. Environ Sci Technol. 38(20): 5306-11.

Proctor DM, Panko JM, Liebig EW, Paustenbach DJ. 2004. Estimating historical occupational exposure to airborne hexavalent chromium in a chromate production plant: 1940–1972. J Occup Environ Hyg 1(11):752–767.

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2003

Crump C, Crump KS, Hack E, Luippold RS, Mundt KA, Panko JP, Liebig EW, Paustenbach DJ, Proctor DM. 2003. Dose-response and risk assessment of airborne hexavalent chromium and lung cancer mortality. Risk Anal. 23(6):1155−1171.

Proctor D, Panko J, Liebig E, Mundt K, Buczynski M, Barnhart R, Harris MA, Morgan R, Finley B, and Paustenbach D. 2003. Workplace concentrations of airborne hexavalent chromium for the Painesville, Ohio chromate production plant. Appl Occ Environ Hyg J. 18(6):430-449.

Proctor DM, Panko JM, Liebig EW, Mundt KA, Buczynski MA, Barnhart RJ, Harris MA, Morgan RJ, Finley BL, Paustenbach DJ. 2003. Workplace airborne hexavalent chromium concentrations for the Painesville, Ohio chromate production plant (1943–1971). Appl Occup Environ Hyg 18(6):430–449.

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Luippold RS, Mundt KA, Austin RP, Liebig EW, Panko JM, Crump C, Crump K, Proctor DM. 2003. Lung cancer mortality among chromate production workers. J Occup Environ Med 60:451–457.

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Crump C, Crump K, Hack E, Luippold R, Mundt K, Liebig EW, Panko JM, Paustenbach DJ, Proctor DM. 2003. Dose-response and risk assessment of airborne hexavalent chromium and lung cancer mortality. Risk Anal 23(6):1147–1163.

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1997

Scott P, Finley B, Harris MA, and Rabbe D. 1997. Determination of background airborne hexavalent chromium concentrations in industrial areas. J Air Waste Manage. Assoc. 47:592-600.

Paustenbach DJ, Panko JM, Fredrick MM, Finley BL, Proctor DM. 1997. Urinary chromium as a biological marker of environmental exposure: What are the limitations? Regul Toxicol Pharmacol 26(1 Pt 2):S23–S34.