Comparison of Noncancer Risk Assessment Approaches for Use in Deriving Drinking Water Criteria

Gibson, Mark C.; deMonsabert, Sharon; Orme‐Zavaleta, Jennifer

doi:10.1006/rtph.1997.1150

Cited by 5 publications

(12 citation statements)

References 34 publications

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“…of H (.) is the link function for logit, probit, and Cloglog, respectively . Following Equation , given the covariates

bold-italicZ

and parameters

Θ

, the probability that the response Y has severity level s at exposure concentration (dose) x is as follows:

\begin{matrix} true \\ left P (Y = k | X, Z, bold-italicΘ) = H (k, X, Z, bold-italicΘ) \\ left - H (k + 1, X, Z, bold-italicΘ), k = 1, ... K - 1, \end{matrix}

P (Y = K | X, bold-italicZ, Θ) = H (K, X, bold-italicZ, Θ) .

Let the number of observations at exposure concentration

x = d_{g}

and severity level k be

n_{g, k}

g = 1, ..., G; k = 0, 1, ..., K

.…”

Section: Methodsmentioning

confidence: 99%

“…The fitted model can be used to estimate the probability of a specific category for any given concentration level. CATREG, with an appropriate statistical model, has been applied to analyzing various types of toxicity data, including differential severity levels, multiple endpoints, exposure duration, and effects on various species . The statistical software CatReg is well suited to ordered categorical data analysis and is downloadable from the U.S. EPA website…”

Section: Introductionmentioning

confidence: 99%

“…The CATREG approach has advantages over the NOAEL approach that are similar to the advantages of the BMD approach, and it is also quantitative and potentially valuable for risk assessment using multiple response data and for combining information across studies. However, despite the availability of data analysis software, applications of CATREG have been limited to comparisons with the BMD and NOAEL approaches in deriving RfDs . This scarcity of applications may be due to the U.S. EPA not having published guidance for its use for chronic risk assessment …”

Section: Introductionmentioning

confidence: 99%

“…CATREG, with an appropriate statistical model, has been applied to analyzing various types of toxicity data, including differential severity levels, multiple endpoints, exposure duration, and effects on various species. (1,2,(10)(11)(12)(13)(14)(15)(16) The statistical software CatReg is well suited to ordered categorical data analysis and is downloadable from the U.S. EPA website. (17) The CATREG approach has advantages over the NOAEL approach that are similar to the advantages of the BMD approach, (10) and it is also quantitative and potentially valuable for risk assessment using multiple response data and for combining information across studies.…”

Section: Introductionmentioning

confidence: 99%

“…However, despite the availability of data analysis software, applications of CATREG have been limited to comparisons with the BMD and NOAEL approaches in deriving RfDs. (1,2,13) This scarcity of applications may be due to the U.S. EPA not having published guidance for its use for chronic risk assessment. (2) Ordinal categorical data usually involve more than one category of severity above no effect, with the categorization often based on histological evaluation and judgment.…”

Section: Introductionmentioning

confidence: 99%

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Benchmark Dose Calculation for Ordered Categorical Responses

Chen

2014

Risk Analysis

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The use of benchmark dose (BMD) calculations for dichotomous or continuous responses is well established in the risk assessment of cancer and noncancer endpoints. In some cases, responses to exposure are categorized in terms of ordinal severity effects such as none, mild, adverse, and severe. Such responses can be assessed using categorical regression (CATREG) analysis. However, while CATREG has been employed to compare the benchmark approach and the no-adverse-effect-level (NOAEL) approach in determining a reference dose, the utility of CATREG for risk assessment remains unclear. This study proposes a CATREG model to extend the BMD approach to ordered categorical responses by modeling severity levels as censored interval limits of a standard normal distribution. The BMD is calculated as a weighted average of the BMDs obtained at dichotomous cutoffs for each adverse severity level above the critical effect, with the weights being proportional to the reciprocal of the expected loss at the cutoff under the normal probability model. This approach provides a link between the current BMD procedures for dichotomous and continuous data. We estimate the CATREG parameters using a Markov chain Monte Carlo simulation procedure. The proposed method is demonstrated using examples of aldicarb and urethane, each with several categories of severity levels. Simulation studies comparing the BMD and BMDL (lower confidence bound on the BMD) using the proposed method to the correspondent estimates using the existing methods for dichotomous and continuous data are quite compatible; the difference is mainly dependent on the choice of cutoffs for the severity levels.

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“…of H (.) is the link function for logit, probit, and Cloglog, respectively . Following Equation , given the covariates

bold-italicZ

and parameters

Θ

, the probability that the response Y has severity level s at exposure concentration (dose) x is as follows:

\begin{matrix} true \\ left P (Y = k | X, Z, bold-italicΘ) = H (k, X, Z, bold-italicΘ) \\ left - H (k + 1, X, Z, bold-italicΘ), k = 1, ... K - 1, \end{matrix}

P (Y = K | X, bold-italicZ, Θ) = H (K, X, bold-italicZ, Θ) .

Let the number of observations at exposure concentration

x = d_{g}

and severity level k be

n_{g, k}

g = 1, ..., G; k = 0, 1, ..., K

.…”

Section: Methodsmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 3 more Smart Citations

Benchmark Dose Calculation for Ordered Categorical Responses

Chen

2014

Risk Analysis

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show abstract

Benchmark dose calculation for ordered categorical responses with multiple endpoints

Chen

Wang

2018

Stoch Environ Res Risk Assess

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Plastic Teabags Release Billions of Microparticles and Nanoparticles into Tea

Hernandez

Larsson

et al. 2019

Environ. Sci. Technol.

772

382

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The increasing presence of micro-and nano-sized plastics in the environment and food chain is of growing concern. Although mindful consumers are promoting the reduction of single-use plastics, some manufacturers are creating new plastic packaging to replace traditional paper uses, such as plastic teabags. The objective of this study was to determine whether plastic teabags could release microplastics and/or nanoplastics during a typical steeping process. We show that steeping a single plastic teabag at brewing temperature (95 °C) releases approximately 11.6 billion microplastics and 3.1 billion nanoplastics into a single cup of the beverage. The composition of the released particles is matched to the original teabags (nylon and polyethylene terephthalate) using Fourier-transform infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS). The levels of nylon and polyethylene terephthalate particles released from the teabag packaging are several orders of magnitude higher than plastic loads previously reported in other foods. An initial acute invertebrate toxicity assessment shows that exposure to only the particles released from the teabags caused dose-dependent behavioral and developmental effects.

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Comparison of Noncancer Risk Assessment Approaches for Use in Deriving Drinking Water Criteria

Cited by 5 publications

References 34 publications

Benchmark Dose Calculation for Ordered Categorical Responses

Benchmark Dose Calculation for Ordered Categorical Responses

Benchmark dose calculation for ordered categorical responses with multiple endpoints

Plastic Teabags Release Billions of Microparticles and Nanoparticles into Tea

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