- NRC (2013) recommended that EPA address whether high dose exposures influence the shape of the dose-response curve. This could be addressed by performing sensitivity analyses in which the high level exposures (e.g., >100 µg/L) are removed from the analyses to assess their impact on the shape of the curve.
- EPA should carefully examine the impact of outlier doses on the fit of its dose-response models.
- EPA should consider whether the data allow for the assessment of the potential for effect modification (i.e., that some groups, such as smokers, may be more sensitive to the effects of iAs) when evaluating dose-response relationships. In the presence of effect modification, iAs exposure may be an exacerbating cofactor, and when considered in this context, the dose response could differ by levels of the cofactor.
REFERENCES
Davis, A., and J. Gift. 2019. Presentation from staff of the U.S. Environmental Protection Agency on Inorganic Arsenic IRIS Dose-Response Analyses to the Committee to Evaluate the IRIS Protocol for Inorganic Arsenic, Washington, DC, July 16, 2019 [online]. Available: https://www.epa.gov/iris/inorganic-arsenic-meetings-webinars [accessed August 23, 2019].
Egger, M., G.D. Smith, and D.G. Altman. 2001. Systematic Reviews in Health Care: Meta-Analysis in Context. Second edition. London: BMJ Publishing Group.
EPA (U.S. Environmental Protection Agency). 2019a. Updated Problem Formulation and Protocol for the Inorganic Arsenic IRIS Assessment [CASRN 7440-38-2]. May 2019. EPA/635/R-19/049. Integrated Risk Information System, National Center for Environmental Assessment, Office of Research and Development, U.S. Environmental Protection Agency, Washington, DC [online]. Available: https://cfpub.epa.gov/ncea/iris_drafts/recordisplay.cfm?deid=34395 [accessed May 28, 2019].
EPA. 2019b. Summary of Public Comments Received on IRIS Inorganic Arsenic Protocol for Transmittal to NAS Committee [online]. Available: https://www.epa.gov/iris/inorganic-arsenic-meetings-webinars [accessed August 23, 2019].
Greenland, S., and M.P. Longnecker. 1992. Methods for trend estimation from summarized dose-response data, with applications to meta-analysis. American Journal of Epidemiology 135(11):1301-1309.
IOM (Institute of Medicine). 2011. Finding What Works in Health Care: Standards for Systematic Reviews. Washington, DC: The National Academies Press.
Lee, J., I. Druwe, J. Gift, and A. Davis. 2019a. Presentation from staff of the U.S. Environmental Protection Agency on Updated Problem Formulation and Scoping to the Committee to Evaluate the IRIS Protocol for Inorganic Arsenic, Washington, DC, July 16, 2019 [online]. Available: https://www.epa.gov/iris/inorganic-arsenic-meetings-webinars [accessed August 23, 2019].
Lee, J., E. Kirrane, and T. Luben. 2019b. Presentation from staff of the U.S. Environmental Protection Agency on Systematic Review Methods Used to Prioritize Health Outcomes to the Committee to Evaluate the IRIS Protocol for Inorganic Arsenic, Washington, DC, July 16, 2019 [online]. Available: https://www.epa.gov/iris/inorganic-arsenic-meetings-webinars [accessed August 23, 2019].
Moher, D., A. Liberati, J. Tetzlaff, and D.G. Altman. The PRISMA Group. 2009. Preferred reporting items for systematic reviews and meta-analyses: The PRISMA statement. PLoS Medicine 6(7):e1000097.
Moon, K.A., S. Oberoi, A. Barchowsky, Y. Chen, E. Guallar, K.E. Nachman, M. Rahman, N. Sohel, D. D’Ippoliti, T.J. Wade, K.A. James, S.F. Farzan, M.R. Karagas, H. Ahsan, and A. Navas-Acien. 2017. A dose-response meta-analysis of chronic arsenic exposure and incident cardiovascular disease. International Journal of Epidemiology 46(6):1924-1939.
NASEM (National Academies of Sciences, Engineering, and Medicine). 2017. Application of Systematic Review Methods in an Overall Strategy for Evaluating Low-Dose Toxicity from Endocrine Active Chemicals. Washington, DC: The National Academies Press.
NASEM. 2018. Progress Toward Transforming the Integrated Risk Information System (IRIS) Program: A 2018 Evaluation. Washington, DC: The National Academies Press.
NRC (National Research Council). 2013. Critical Aspects of EPA’s IRIS Assessment of Inorganic Arsenic: Interim Report. Washington, DC: The National Academies Press.
NRC. 2014. Review of EPA’s Integrated Risk Information System (IRIS) Process. Washington, DC: The National Academies Press.
Piegorsch, W.W., and A.J. Bailer. 1997. Statistics for Environmental Biology and Toxicology. First edition. London, England: Chapman and Hall.
Sabanés Bové, D., and L. Held. 2011. Bayesian fractional polynomials. Statistics and Computing 21:309-324.
Steinmaus, C., C. Ferreccio, J. Acevedo, Y. Yuan, J. Liaw, V. Durán, S. Cuevas, J. García, R. Meza, R. Valdés, G. Valdés, H. Benítez, V. VanderLinde, V. Villagra, K.P. Cantor, L.E. Moore, S.G. Perez, S. Steinmaus, and A.H. Smith. 2014. Increased lung and bladder cancer incidence in adults after in utero and early-life arsenic exposure. Cancer Epidemiology, Biomarkers & Prevention 23(8):1529-1538.
Thayer, K. 2019. Presentation from Director, Integrated Risk Information System Program, U.S. Environmental Protection Agency, on Introduction and Role of the Protocol in the IRIS Systematic Review Process to the Committee to Evaluate the IRIS Protocol for Inorganic Arsenic, Washington, DC, July 16, 2019 [online]. Available: https://www.epa.gov/iris/inorganic-arsenic-meetings-webinars [accessed August 23, 2019].