Exposure assessment perspectives

From an exposure assessment perspective. Fig. 2 also demonstrates that, depending on an individual s location within a city, the outdoor UFP number... 

Severn, D.J. (1982) Exposure assessment for agricultural chemicals, in Genetic Toxicology, and Agricultural Perspective, Fleck, R.A. and Hollander, A., Eds., Plenum Press, New York, pp. 235-242. 

Dietert, R.R. and Piepenbrink, M.S., Perinatal immunotoxicity why adult exposure assessment fails to predict risk, Environ. Health Perspect., 114, 477, 2006. 

Silva MJ, Reidy JA, Preau JL Jr, Needham LL, Calafat AM (2006) Oxidative metabolites of diisononyl phthalate as biomarkers for human exposure assessment. Environ Health Perspect 114 1158-1161... 

Cohen-Hubal EA, Sheldon LS, Burke JM, McCurdy TR, Berry MR, Rigas ML, Zartarian VG, Freeman NC (2000) Children s exposure assessment A review of factors influencing children s exposure, and the data available to characterize and assess that exposure. Environ Health Perspect, 108 475-486. 

Sioutas C, Delfino RJ, Singh M (2005) Exposure assessment for atmospheric ultrafine particles (UFPs) and implications in epidemiological research. Environ Health Perspect 113 947-955... 

Lioy, P.J., Freeman, N.C. and Millette, J.R. (2002) Dust a metric for use in residential and building exposure assessment and source characterization. Environmental Health Perspectives, 110, 969-82. 

Lee, L.W., J. Griffith, H. Zenick, and B.S. Hulka. 1995. Human tissue monitoring and specimen banking Opportunities for exposure assessment, risk assessment, and epidemiologic research. Environ. Health Perspect. 103(Suppl. 3) 3-8. 

Ozkaynak, H., R.M. Whyatt, L.L. Needham, G. Akland, and J. Quackenboss. 2005. Exposure assessment implications for the design and implementation of the National Children s Study. Environ. Health Perspect. 113(8) 1108-1115. 

Emond, C, J.E. Michalek, L.S. Birnbaum, and M.J. DeVito. 2005b. Comparison of the use of a physiologically based pharmacokinetic model and a classical pharmacokinetic model for dioxin exposure assessment. Environ. Health Perspect. 113(12) 1666-1668. 

Weis, B.K., D. Balshawl, J.R. Barr, D. Brown, M. Ellisman, P. Lioy, G. Omenn, J.D. Potter, M.T. Smith, L. Sohn, W.A. Suk, S. Sumner, J. Swenberg, D.R. Walt, S. Watkins, C. Thompson, and S.H. Wilson. 2005. Personalized exposure assessment Promising approaches for human environmental health research. Environ. Health Perspect. 113(7) 840-848. 

As indicated above and discussed below, the health effects of DEHP are generally well characterized by the oral route in laboratory animal models. While additional information is always desirable, from a health assessment perspective, there appear to be few overriding needs for additional toxicological information for the principal route of human exposure to DEHP. Of particular importance are additional data that could enable derivation of an acute-duration oral MRL, which is currently precluded by insufficient information on male reproductive system development in offspring acutely exposed during gestation and/or lactation. 

As noted above, the lowest effective doses in adults and young are often similar. However, the type and severity of effects from an exposure may be very different. This becomes an important consideration, especially in evaluating prenatal animal studies. Because the developing embryo/fetus is exposed in the maternal animal, it has been argued that if maternal toxicity is observed, any developmental toxicity could be due to the compromised maternal system. However, several issues should be considered. The difference between the lowest maternally toxic dose and the developmentally toxic dose may at times be related to the relative thoroughness with which endpoints are evaluated in dams and offspring, as well as to the sensitivity of the end-points. Moreover, the severity of the effects must be considered the developmental effects may be permanent, while the maternal effects may be reversible. From a risk assessment perspective, developmental toxicity in the presence of maternal toxicity cannot be simply considered secondary to maternal toxicity and discounted (USEP A, 1991). 

Needham LL, Ozkaynak H, Whyatt RM, Barr DB, Wang RY, Naeher L, Akland G, Bahadori T, Bradman A, Fortmann R, Liu L-JS, Morandi M, O Rourke MK, Thomas K, Quackenboss J, Ryan PB, Zartarian V (2005) Exposure assessment in the national children s study introduction. Environ Health Perspect, 113(8) 1076-1082. 

The remainder of the document is organized as follows. The next two sections lay the foundations for the terminology used in the document section 2 defines data in the context of exposure assessments and section 3 introduces a broader concept of data quality characterized by the four hallmarks or measures of quality mentioned above— appropriateness, accuracy, integrity and transparency. Section 4 discusses how these hallmarks might be applied to the design or evaluation of an exposure assessment to ensure its quality. The final section concludes with a broader perspective on the role of data quality in exposure assessment and its importance to risk assessment and risk management decisions. 

Hallmarks of data quality are important to the characterization and communication of uncertainty, not just from the perspective of the exposure analyst, but also from the perspective of the target audiences for the exposure assessment. For example, lack of transparency in a source document (e.g. a monitoring study) used in the assessment should be considered by the original investigators as a source of uncertainty, whereas lack of transparency in the report of the exposure assessment may introduce uncertainty or lack of confidence from the perspective of its likely users. 

Weis BK, Balshawl D, Barr IR, Brown D, Ellisman M, Liov P, Omenn G, Potter ID, Smith MT, Sohn L, Suk WA, Sumner S, Swenberg I, Walt DR, Watkins S, Thompson C, Wilson SH. 2005. Personalized exposure assessment promising approaches for human environmental health research. Environ Health Perspect 113 840-848. 

Occupational pesticide exposure holds a peculiar status within the field of occupational health and safety, both from a scientific and regulatory perspective. Methods for personal monitoring of dermal exposure first arose in the context of pesticide applications in agriculture, pioneered by scientists in the USA Public Health Service (Batchelor and Walker, 1954 Durham and Wolfe, 1962). These methods gained worldwide recognition in the early 1960s, and remain a component of exposure assessment practice today. This work pre-dated most personal monitoring methods that were developed for industrial workplaces. 

Cohen Hubal, E.A., L.S. Sheldon, J.M. Burke, T.R. McCurdy, M.R. Berry, M.L. Rigas, V.G. Zartarian and N.C.G. Freeman (2000). Children s Exposure Assessment A Review of Factors Influencing Children s Exposure, and the Data Available to Characterize and Assess that Exposure, Environ. Health Perspect., 108, 475-486. 

Mitchell, M. and C. Campbell (2001). Probabilistic Exposure Assessment of Operator and Residential Exposure A Canadian Regulatory Perspective, Ann. Occup. Hyg., 45, S43-S47. 

Fukata, H., Omori, M., Osada, H., Todaka, E., Mori, C. Necessity to measure PCBs and organochlorine pesticide concentrations in human umbilical cords for fetal exposure assessment. Environ. Health Perspect. 113, 297-303 (2005)... 

Smith TJ, Hammon SK, Wong O. 1993. Health effects of gasoline exposure. I. Exposure assessment for U.S. distribution workers. Environmental Health Perspectives Supplements 101 (Suppl. 6) 13-21. 

Verner, M. A., Charbonneau, M., Lopez-Carrillo, L., and Haddad, S. (2008). Physiologically based pharmacokinetic modeling of persistent organic pollutants for lifetime exposure assessment A new tool in breast cancer epidemiologic studies. Environ Health Perspect 116, 886-892. 

Kohlmeier, L., and M. Kohlmeier. 1995. Adipose tissue as a mediiun for epidemiologic exposure assessment. Environ. Health Perspect. 103(Suppl.3) 99-106. 

The NRC document calls for hazard identification, dose-response assessment, exposure assessment, and risk characterization. In an effort to place descriptive experimental toxicity results in a clearer perspective and place more emphasis on evaluation, this outline deviates slightly from the NRC document and calls for hazard evaluation, hazard extrapolation, exposure assessment and risk characterization. In addition, a few comments on risk acceptability are given. Exposure assessments have been adequately discussed elsewhere in this symposium and will be discussed here only as they relate to hazard identification, evaluation, extrapolation and risk characterization. 

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