A quantitative screening-level approach to incorporate chemical exposure and risk into alternative assessment evaluations.

As the general public and retailers ask for disclosure of chemical ingredients in the marketplace, a number of hazard screening tools were developed to evaluate the so-called "greenness" of individual chemical ingredients and/or formulations. The majority of these tools focus only on hazard, often using chemical lists, ignoring the other part of the risk equation: exposure. Using a hazard-only focus can result in regrettable substitutions, changing 1 chemical ingredient for another that turns out to be more hazardous or shifts the toxicity burden to others. To minimize the incidents of regrettable substitutions, BizNGO describes "Common Principles" to frame a process for informed substitution. Two of these 6 principles are: "reduce hazard" and "minimize exposure." A number of frameworks have emerged to evaluate and assess alternatives. One framework developed by leading experts under the auspices of the US National Academy of Sciences recommended that hazard and exposure be specifically addressed in the same step when assessing candidate alternatives. For the alternative assessment community, this article serves as an informational resource for considering exposure in an alternatives assessment using elements of problem formulation; product identity, use, and composition; hazard analysis; exposure analysis; and risk characterization. These conceptual elements build on practices from government, academia, and industry and are exemplified through 2 hypothetical case studies demonstrating the questions asked and decisions faced in new product development. These 2 case studies-inhalation exposure to a generic paint product and environmental exposure to a shampoo rinsed down the drain-demonstrate the criteria, considerations, and methods required to combine exposure models addressing human health and environmental impacts to provide a screening level hazard and exposure (risk) analysis. This article informs practices for these elements within a comparative risk context to improve alternatives assessment evaluation and decision making. Integr Environ Assess Manag 2017;13:1007-1022. © 2017 The Authors. Integrated Environmental Assessment and Management published by Wiley Periodicals, Inc. on behalf of Society of Environmental Toxicology & Chemistry (SETAC).

Gender differences in the incidence of background and chemically induced primary pulmonary neoplasms in B6C3F1 mice: a retrospective analysis of the National Toxicology Program (NTP) carcinogenicity bioassays.

The National Toxicology Program (NTP) database of technical reports on carcinogenicity bioassays has been interrogated for the incidence of primary pulmonary neoplasms in B6C3F1 mice. A total of 170 study reports were selected, from studies that completed the in-life phase during 1983-2007, which included neoplasm incidence data for 180 control groups comprising both male and female mice. The incidence (median and inter-quartile range) of males with alveolar/bronchiolar adenoma was 16% (12-20%), and for females it was 5% (2-8%); the incidence of males with alveolar/bronchiolar carcinoma was 8% (4-12%), and for females it was 2% (0-4%); and the incidence of males with combined alveolar/bronchiolar adenoma or carcinoma was 24% (18-30%), and for females it was 8% (6-12%). Comparing the incidence of animals bearing these lesions on a per study basis showed the median incidence in males to be 3.0-fold, 2.0-fold, and 2.8-fold higher than in females. The incidence of other primary pulmonary neoplasms was <10% of the alveolar/bronchiolar neoplasms. Comparison of gender-specific response to lung tumorigens showed that the increase in incidence of tumors above control levels was greater in females than in males.