Testing For Regulatory Purposes Research Articles

Options for substantiating protein content claims for conventional foods.

In Canada and the United States, front-of-package protein content claims require data to support the quality of the protein. In general, protein quality reflects the product of the amino acid composition of the food protein relative to human amino acid requirements and a measure of digestibility. The currently accepted method in both jurisdictions is the protein digestibility-corrected amino acid score (PDCAAS) that requires the measurement of true fecal protein (nitrogen) digestibility. The latter must be measured in vivo using a rat model. This requirement for animal testing is inconsistent with international efforts to reduce the usage of animals in testing for regulatory purposes. The current commentary positions four options to remove the need to use animal testing for determining protein quality, when considering protein content claim substantiation. These options include (i) a focus on protein quantity alone; (ii) the use of the amino acid score alone, with no correction for digestibility; (iii) the use of a fixed digestibility coefficient to estimate protein quality; and (iv) the use of in vitro methods to measure protein and/or amino acid digestibility. The relative merits and deficiencies of the options are positioned with the goal of encouraging dialogue within the regulatory agencies to move towards alternative approaches for substantiating protein content claims on foods, including those derived from plant-based sources.

Human Umbilical Cord Mesenchymal Stem Cell-Based in vitro Model for Neurotoxicity Testing.

Neurotoxicity (NT) testing for regulatory purposes is based on in vivo animal testing. There is general consensus, however, about the need for the development of alternative methodologies to allow researchers to more rapidly and cost effectively screen large numbers of chemicals for their potential to cause NT, or to investigate their mode of action. In vitro assays are considered an important source of information for making regulatory decisions, and human cell-based systems are recommended as one of the most relevant models in toxicity testing, to reduce uncertainty in the extrapolation of results from animal-based models. Human neuronal models range from various neuroblastoma cell lines to stem cell-derived systems, including those derived from mesenchymal stem/stromal cells (hMSC). hMSCs exhibit numerous advantages, including the fact that they can be obtained in high yield from healthy human adult tissues, can be cultured with a minimal laboratory setup and without genetic manipulations, are able of continuous and repeated self-renewal, are nontumorigenic, and can form large populations of stably differentiated cells representative of different tissues, including neuronal cells. hMSCs derived from human umbilical cord (hUC) in particular possess several prominent advantages, including a painless, non-invasive, and ethically acceptable collection procedure, simple and convenient preparation, and high proliferation capacity. In addition, hMSCs can be efficiently differentiated into neuron-like cells (hNLCs), which can then be used for the assessment of neuronal toxicity of potential neurotoxic compounds in humans. Here, we describe a step-by-step procedure to use hMSCs from the umbilical cord for in vitro neurotoxicity testing. First, we describe how to isolate, amplify, and store hMSCs derived from the umbilical cord. We then outline the steps to transdifferentiate these cells into hNLCs, and then use the hNLCs for neurotoxicity testing by employing multiple common cytotoxicity assays after treatment with test compounds. The approach follows the most updated guidance on using human cell-based systems. These protocols will allow investigators to implement an alternative system for obtaining primary NLCs of human origin, and support advancement in neurotoxicity research. © 2022 The Authors. Current Protocols published by Wiley Periodicals LLC. Basic Protocol 1: Isolation and maintenance of human mesenchymal stem/stromal cells (hMSCs) obtained from the umbilical cord lining membrane Basic Protocol 2: Transdifferentiation of hMSCs into neuron-like cells (hNLCs) and basic neurotoxicity assessment.

Consensus statement on the need for innovation, transition and implementation of developmental neurotoxicity (DNT) testing for regulatory purposes

This consensus statement voices the agreement of scientific stakeholders from regulatory agencies, academia and industry that a new framework needs adopting for assessment of chemicals with the potential to disrupt brain development. An increased prevalence of neurodevelopmental disorders in children has been observed that cannot solely be explained by genetics and recently pre- and postnatal exposure to environmental chemicals has been suspected as a causal factor. There is only very limited information on neurodevelopmental toxicity, leaving thousands of chemicals, that are present in the environment, with high uncertainty concerning their developmental neurotoxicity (DNT) potential. Closing this data gap with the current test guideline approach is not feasible, because the in vivo bioassays are far too resource-intensive concerning time, money and number of animals. A variety of in vitro methods are now available, that have the potential to close this data gap by permitting mode-of-action-based DNT testing employing human stem cells-derived neuronal/glial models. In vitro DNT data together with in silico approaches will in the future allow development of predictive models for DNT effects. The ultimate application goals of these new approach methods for DNT testing are their usage for different regulatory purposes.

Cost-Effectiveness Analysis of Chemical Testing for Decision-Support: How to Include Animal Welfare?

ABSTRACT Toxicity testing for regulatory purposes raises the question of test selection for a particular endpoint. Given the public's concern for animal welfare, test selection is a multi-objective decision problem that requires balancing information outcome, animal welfare loss, and monetary testing costs. This paper demonstrates the applicability of cost-effectiveness analysis as a decision-support tool for test selection in a regulatory context such as, for example, the new European chemicals legislation (REACH). We distinguish different decision-making perspectives, in particular the regulator's and chemical industry's perspectives, and we discuss how cost-effectiveness analysis can be applied to test selection from both perspectives. Furthermore, we show how animal welfare goals can be included in cost-effectiveness analyses, and we provide a three-dimensional extension to the standard cost-effectiveness analysis if animal welfare loss cannot be valued in monetary terms. To illustrate how cost-effectiveness analysis works in different settings, we apply our model to a simple case of selecting short-term tests for mutagenicity. We demonstrate that including sufficiently high values for animal welfare induces cost-effective replacements of animal testing. Furthermore, we show that the regulator and chemical companies face different tradeoffs when selecting tests. This may lead to different choices of tests or testing systems.

Factors stimulating or obstructing the implementation of the 3Rs in the regulatory process

Approximately 30% of animal use within the European Union (EU) is done to meet regulatory requirements. The tests are often repetitive in nature and may cause severe suffering, due to the procedures used and to rigidly predefined end points. In addition, product evaluation procedures often take long and are very expensive. Over the last decades the heavy reliance on animal experimentation in this area has met serious objections, both ethical and economical in nature. This study describes obstacles and opportunities to implement the 3Rs in regulatory animal testing. The findings are based primarily on interviews with legislators, regulators, industry, science and animal welfare organisations and reflect shared perceptions of these respondents. In order to increase the application of the 3Rs in regulatory testing a number of technical, political and social obstacles must be overcome. This study offers insight into the persistent character of regulatory animal testing and can function as a starting point for further discussion on how to tackle these problems. To this end, several recommendations are made ranging from strategic test approaches and data sharing to strengthening the policy network and improving communication between 3Rs experts and regulators. The study is an initiative of the national project group "Regulatory Animal Testing", which consists of a group of Dutch experts on animal testing working for a variety of organisations in the field.1 They felt the need for cooperation to initiate a discussion at relevant levels and to identify possible solutions in order to implement the objectives of the three R's in testing for regulatory purposes without loss of scrutiny in safety and/or efficacy evaluation needed for product release.

Interpretation of data from nonstandard studies: The fate of octamethylcyclotetrasiloxane in a sediment/water microcosm system

As part of a TSCA Section 4 Consent Order agreement, the biodegradation of the organosilicone octamethylcyclotetrasiloxane (OMCTS) was investigated using an updated version of the Bourquin Eco-Core design. This study illustrates the concept that caution must be exercised in all data interpretation but especially when nonstandardized studies are used in the regulatory decision-making process. Because of OMCTS' unique combination of high volatility and low water solubility, modifications to the test procedures were necessary, as were a series of supplemental studies conducted to aid in the interpretation of the original study results. While the correct interpretation of the data was achieved, the use of supplemental studies highlights the importance of professional judgment in conducting testing for regulatory purposes. Researchers should not hesitate to question the appropriateness of standard and nonstandard study designs as related to the specific physicochemical properties of the test material being investigated (e.g., Henry's Law constant). In addition, investigators should be prepared to conduct supplemental studies and analyses as needed to ensure the accurate interpretation of study results. Misinterpretation of data can have serious ramifications in a regulatory context, whether it may result in keeping an environmentally sound product off the market, in misdirection of limited financial and personnel resources away from more serious environmental concerns, or in placing unwarranted limitations on a given chemical or chemical product. © 1996 by John Wiley & Sons, Inc.