Deborah Proctor, B.S.
Managing Principal Scientist


Phone(949) 459-1676
Fax(949) 459-5943
LocationOrange County, CA
Address27001 La Paz Road
Suite 260
Mission Viejo, CA 92691



Professional Profile

Ms. Deborah Proctor has more than 30 years of experience in environmental and occupational health risk assessment, specializing in applied toxicology, mode-of-action evaluations for chemical carcinogens, air toxics and air pollution risk assessment, exposure reconstruction, and quantitative dose-response analysis for the purpose of developing toxicity criteria.

Ms. Proctor has technical expertise for assessing the potential human health risk associated with contaminated air, soil, sediments, groundwater, biota, and consumer products; evaluating failure-to-warn litigation claims pursuant to California Proposition 65, including determination of Safe Harbor Levels; designing risk-based site investigations; assessing the environmental fate and toxicity of metals in the environment; determining the bioavailability of metals in soil and solid media; and risk/hazard communications. Ms. Proctor has conducted studies of oral and inhalation bioaccessibility for metals in alloys, slags, and affected soil, dust, and baghouse dust, and has designed and conducted relative bioavailability studies for cobalt, nickel, and manganese. Ms. Proctor uses state-of-the-art scientific approaches to evaluate potential hazards and develop health-protective and science-driven remediation goals. She provides technical comments to regulatory agencies on policy and guidance documents, and technical support for public communication. Ms. Proctor has designed studies involving human volunteers and is experienced with the use of Internal Review Boards (IRBs) and the ethical requirements and considerations associated with research involving humans.

Ms. Proctor is a nationally recognized expert regarding the potential health risks associated with occupational and environmental exposure to chromium. She has published extensively in this field and managed research projects that have been used to develop federal and state regulatory health criteria. Additionally, she has extensive experience in metals risk assessment and specific expertise for evaluation of nickel, cobalt, titanium, manganese, lead, vanadium, beryllium, and arsenic. Ms. Proctor has experience using physiologically based pharmacokinetic (PBPK) modeling in risk assessment for chromium, lead, manganese, and perchlorate.

Ms. Proctor’s research has been applied to support regulatory decisions and inform health-based criteria.  Specific examples include the USEPA Inhalation Reference Concentration for hexavalent chromium using Malsh et al. (1994), the OSHA risk assessment for the 2006 Hexavalent Chromium Rule and revised Permissible Exposure Limit using Luippold et al. (2003); Crump et al. (2003), and Proctor et al. (2003; 2004), USEPA Office of Prevention, Pesticides and Toxic Substances 2008 Reregistration Eligibility Decision (RED) for Chromated Arsenicals using Technical Study Reports FPRL #012506 and FPRL #012406; and the New Jersey Department of Environmental Protection Soil Cleanup Criteria for dermal contact with hexavalent chromium using Fowler et al. (1999). She recently published an adverse outcome pathway (AOP) analysis for rodent forestomach tumors by nongenotoxic initiating events (Proctor et al., 2018).

Ms. Proctor is a regular science peer reviewer for the Journal of Applied Toxicology, Toxicology, Regulatory Toxicology and Pharmacology, Chemico-Biological Interactions, and PLOS1.