A 10-step framework for use of read-across (RAX) in next generation risk assessment (NGRA) for cosmetics safety assessment

This paper presents a 10-step read-across (RAX) framework for use in cases where a threshold of toxicological concern (TTC) approach to cosmetics safety assessment is not possible. RAX builds on established approaches that have existed for more than two decades using chemical properties and in silico toxicology predictions, by further substantiating hypotheses on toxicological similarity of substances, and integrating new approach methodologies (NAM) in the biological and kinetic domains. NAM include new types of data on biological observations from, for example, in vitro assays, toxicogenomics, metabolomics, receptor binding screens and uses physiologically-based kinetic (PBK) modelling to inform about systemic exposure. NAM data can help to substantiate a mode/mechanism of action (MoA), and if similar chemicals can be shown to work by a similar MoA, a next generation risk assessment (NGRA) may be performed with acceptable confidence for a data-poor target substance with no or inadequate safety data, based on RAX approaches using data-rich analogue(s), and taking account of potency or kinetic/dynamic differences.

Rethinking Nano-TiO2 Safety: Overview of Toxic Effects in Humans and Aquatic Animals

Titanium dioxide nanoparticles (nano-TiO₂ ) are widely used in consumer products, raising environmental and health concerns. An overview of the toxic effects of nano-TiO₂ on human and environmental health is provided. A meta-analysis is conducted to analyze the toxicity of nano-TiO₂ to the liver, circulatory system, and DNA in humans. To assess the environmental impacts of nano-TiO₂ , aquatic environments that receive high nano-TiO₂ inputs are focused on, and the toxicity of nano-TiO₂ to aquatic organisms is discussed with regard to the present and predicted environmental concentrations. Genotoxicity, damage to membranes, inflammation and oxidative stress emerge as the main mechanisms of nano-TiO₂ toxicity. Furthermore, nano-TiO₂ can bind with free radicals and signal molecules, and interfere with the biochemical reactions on plasmalemma. At the higher organizational level, nano-TiO₂ toxicity is manifested as the negative effects on fitness-related organismal traits including feeding, reproduction and immunity in aquatic organisms. Bibliometric analysis reveals two major research hot spots including the molecular mechanisms of toxicity of nano-TiO₂ and the combined effects of nano-TiO₂ and other environmental factors such as light and pH. The possible measures to reduce the harmful effects of nano-TiO₂ on humans and non-target organisms has emerged as an underexplored topic requiring further investigation.

Nanotoxicology: The Need for a Human Touch?

With the ever-expanding number of manufactured nanomaterials (MNMs) under development there is a vital need for nanotoxicology studies that test the potential for MNMs to cause harm to health. An extensive body of work in cell cultures and animal models is vital to understanding the physicochemical characteristics of MNMs and the biological mechanisms that underlie any detrimental actions to cells and organs. In human subjects, exposure monitoring is combined with measurement of selected health parameters in small panel studies, especially in occupational settings. However, the availability of further in vivo human data would greatly assist the risk assessment of MNMs. Here, the potential for controlled inhalation exposures of MNMs in human subjects is discussed. Controlled exposures to carbon, gold, aluminum, and zinc nanoparticles in humans have already set a precedence to demonstrate the feasibility of this approach. These studies have provided considerable insight into the potential (or not) of nanoparticles to induce inflammation, alter lung function, affect the vasculature, reach the systemic circulation, and accumulate in other organs. The need for further controlled exposures of MNMs in human volunteers - to establish no-effect limits, biological mechanisms, and provide vital data for the risk assessment of MNMs - is advocated.

Safety Considerations of Cancer Nanomedicine-A Key Step toward Translation

The rate of translational effort of nanomedicine requires strategic planning of nanosafety research in order to enable clinical trials and safe use of nanomedicine in patients. Herein, the experiences that have emerged based on the safety data of classic liposomal formulations in the space of oncology are discussed, along with a description of the new challenges that need to be addressed according to the rapid expansion of nanomedicine platform beyond liposomes. It is valuable to consider the combined use of predictive toxicological assessment supported by deliberate investigation on aspects such as absorption, distribution, metabolism, and excretion (ADME) and toxicokinetic profiles, the risk that may be introduced during nanomanufacture, unique nanomaterials properties, and nonobvious nanosafety endpoints, for example. These efforts will allow the generation of investigational new drug-enabling safety data that can be incorporated into a rational infrastructure for regulatory decision-making. Since the safety assessment relates to nanomaterials, the investigation should cover the important physicochemical properties of the material that may lead to hazards when the nanomedicine product is utilized in humans.

Potential frameworks to support evaluation of mechanistic data for developmental neurotoxicity outcomes: A symposium report

A key challenge in systematically incorporating mechanistic data into human health assessments is that, compared to studies of apical health endpoints, these data are both more abundant (mechanistic studies routinely outnumber other studies by several orders of magnitude) and more heterogeneous (e.g. different species, test system, tissue, cell type, exposure paradigm, or specific assays performed). A structured decision-making process for organizing, integrating, and weighing mechanistic DNT data for use in human health risk assessments will improve the consistency and efficiency of such evaluations. At the Developmental Neurotoxicology Society (DNTS) 2016 annual meeting, a symposium was held to address the application of existing organizing principles and frameworks for evaluation of mechanistic data relevant to interpreting neurotoxicology data. Speakers identified considerations with potential to advance the use of mechanistic DNT data in risk assessment, including considering the context of each exposure, since epigenetics, tissue type, sex, stress, nutrition and other factors can modify toxicity responses in organisms. It was also suggested that, because behavior is a manifestation of complex nervous system function, the presence and absence of behavioral change itself could be used to organize the interpretation of multiple complex simultaneous mechanistic changes. Several challenges were identified with frameworks and their implementation, and ongoing research to develop these approaches represents an early step toward full evaluation of mechanistic DNT data for assessments.

Transitioning to composite bacterial mutagenicity models in ICH M7 (Q)SAR analyses

The International Council on Harmonisation (ICH) M7(R1) guideline describes the use of complementary (quantitative) structure-activity relationship ((Q)SAR) models to assess the mutagenic potential of drug impurities in new and generic drugs. Historically, the CASE Ultra and Leadscope software platforms used two different statistical-based models to predict mutations at G-C (guanine-cytosine) and A-T (adenine-thymine) sites, to comprehensively assess bacterial mutagenesis. In the present study, composite bacterial mutagenicity models covering multiple mutation types were developed. These new models contain more than double the number of chemicals (n = 9,254 and n = 13,514) than the corresponding non-composite models and show better toxicophore coverage. Additionally, the use of a single composite bacterial mutagenicity model simplifies impurity analysis in an ICH M7 (Q)SAR workflow by reducing the number of model outputs requiring review. An external validation set of 388 drug impurities representing proprietary pharmaceutical chemical space showed performance statistics ranging from of 66-82% in sensitivity, 91-95% in negative predictivity and 96% in coverage. This effort represents a major enhancement to these (Q)SAR models and their use under ICH M7(R1), leading to improved patient safety through greater predictive accuracy, applicability, and efficiency when assessing the bacterial mutagenic potential of drug impurities.

Use cases, best practice and reporting standards for metabolomics in regulatory toxicology

Metabolomics is a widely used technology in academic research, yet its application to regulatory science has been limited. The most commonly cited barrier to its translation is lack of performance and reporting standards. The MEtabolomics standaRds Initiative in Toxicology (MERIT) project brings together international experts from multiple sectors to address this need. Here, we identify the most relevant applications for metabolomics in regulatory toxicology and develop best practice guidelines, performance and reporting standards for acquiring and analysing untargeted metabolomics and targeted metabolite data. We recommend that these guidelines are evaluated and implemented for several regulatory use cases.

The UK Food Standards Agency Draft Report on Variability and Uncertainty in Toxicology: A Response by FRAME

At the request of the Food Standards Agency, the Committee on Toxicity of Chemicals in Food, Consumer Products and the Environment (COT) established a Working Group on Variation and Uncertainty in Toxicology (WG VUT). In April 2006, the WG VUT produced a draft report for public consultation. FRAME made a submission in response to this consultation in July 2006. We commend the WG VUT for its comprehensive account of many of the problems associated with risk assessment, and for making recommendations about the problems that need to be addressed. We were particularly encouraged by the WG VUTs recognition of the need for guidelines on how toxicological studies should be conducted and data analysed. However, we believe that the report has not achieved all of its objectives. It does not adequately consider how modern technologies, experimental design, statistical analysis and species extrapolation can be used in practice to address variability and uncertainty. There is a disproportionate focus on the sources of variability and uncertainty in human data, with relatively little consideration of how variation and uncertainty due to animal tests can be addressed. Furthermore, it is clear that, until the advantages and limitations of all toxicological methods are fully appraised and testing strategies and guidelines are agreed, the scope for improving the existing approaches to risk assessment will be severely limited. Hence, the use of alternative methods for hazard identification and characterisation merit more consideration than they were given in the draft report.

Report from the BfR expert hearing on practicability of hormonal measurements: recommendations for experimental design of toxicological studies with integrated hormonal end points

This publication summarizes discussions that were held during an international expert hearing organized by the German Federal Institute for Risk Assessment (BfR) in Berlin, Germany, in October 2017. The expert hearing was dedicated to providing practical guidance for the measurement of circulating hormones in regulatory toxicology studies. Adequate measurements of circulating hormones have become more important given the regulatory requirement to assess the potential for endocrine disrupting properties for all substances covered by the plant protection products and biocidal products regulations in the European Union (EU). The main focus was the hypothalamus-pituitary-thyroid axis (HPT) and the hypothalamus-pituitary-gonadal axis (HPG). Insulin, insulin-like growth factor 1 (IGF-1), parathyroid hormone (PTH) and vitamins A and D were also discussed. During the hearing, the experts agreed on specific recommendations for design, conduct and evaluation of acceptability of studies measuring thyroid hormones, thyroid stimulating hormone and reproductive hormones as well as provided some recommendations for insulin and IGF-1. Experts concluded that hormonal measurements as part of the test guidelines (TGs) of the Organisation for Economic Co-operation and Development (OECD) were necessary on the condition that quality criteria to guarantee reliability and reproducibility of measurements are adhered to. Inclusion of the female reproductive hormones in OECD TGs was not recommended unless the design of the study was modified to appropriately measure hormone concentrations. The current report aims at promoting standardization of the experimental designs of hormonal assays to allow their integration in OECD TGs and highlights research needs for better identification of endocrine disruptors using hormone measurements.

Identifying Unreported Opioid Deaths Through Toxicology Data and Vital Records Linkage: Case Study in Marion County, Indiana, 2011-2016

OBJECTIVES

To demonstrate the severity of undercounting opioid-involved deaths in a local jurisdiction with a high proportion of unspecified accidental poisoning deaths.

METHODS

We matched toxicology data to vital records for all accidental poisoning deaths (n = 1238) in Marion County, Indiana, from January 2011 to December 2016. From vital records, we coded cases as opioid involved, specified other substance, or unspecified. We extracted toxicology data on opioid substances for unspecified cases, and we have reported corrected estimates of opioid-involved deaths after accounting for toxicology findings.

RESULTS

Over a 6-year period, 57.7% of accidental overdose deaths were unspecified and 34.2% involved opioids. Toxicology data showed that 86.8% of unspecified cases tested positive for an opioid. Inclusion of toxicology results more than doubled the proportion of opioid-involved deaths, from 34.2% to 86.0%.

CONCLUSIONS

Local jurisdictions may be undercounting opioid-involved overdose deaths to a considerable degree. Toxicology data can improve accuracy in identifying opioid-involved overdose deaths. Public Health Implications. Mandatory toxicology testing and enhanced training for local coroners on standards for death certificate reporting are needed to improve the accuracy of local monitoring of opioid-involved accidental overdose deaths.

A call for action: Improve reporting of research studies to increase the scientific basis for regulatory decision-making

This is a call for action to scientific journals to introduce reporting requirements for toxicity and ecotoxicity studies. Such reporting requirements will support the use of peer-reviewed research studies in regulatory decision-making. Moreover, this could improve the reliability and reproducibility of published studies in general and make better use of the resources spent in research.

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.

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An increased prevalence of neurodevelopmental disorders in children is observed.

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There is very limited information on neurodevelopmental toxicity (DNT) induced by environmental chemicals.

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A new framework is required for assessment of chemicals with the potential to disrupt brain development.

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In vitro DNT data together with in silico approaches should be used for regulatory purposes.

Risk, Uncertainty and Precaution in Science: The Threshold of the Toxicological Concern Approach in Food Toxicology

Environmental risk assessment is often affected by severe uncertainty. The frequently invoked precautionary principle helps to guide risk assessment and decision-making in the face of scientific uncertainty. In many contexts, however, uncertainties play a role not only in the application of scientific models but also in their development. Building on recent literature in the philosophy of science, this paper argues that precaution should be exercised at the stage when tools for risk assessment are developed as well as when they are used to inform decision-making. The relevance and consequences of this claim are discussed in the context of the threshold of the toxicological concern approach in food toxicology. I conclude that the approach does not meet the standards of an epistemic version of the precautionary principle.

How Adverse Outcome Pathways Can Aid the Development and Use of Computational Prediction Models for Regulatory Toxicology

Efforts are underway to transform regulatory toxicology and chemical safety assessment from a largely empirical science based on direct observation of apical toxicity outcomes in whole organism toxicity tests to a predictive one in which outcomes and risk are inferred from accumulated mechanistic understanding. The adverse outcome pathway (AOP) framework provides a systematic approach for organizing knowledge that may support such inference. Likewise, computational models of biological systems at various scales provide another means and platform to integrate current biological understanding to facilitate inference and extrapolation. We argue that the systematic organization of knowledge into AOP frameworks can inform and help direct the design and development of computational prediction models that can further enhance the utility of mechanistic and in silico data for chemical safety assessment. This concept was explored as part of a workshop on AOP-Informed Predictive Modeling Approaches for Regulatory Toxicology held September 24-25, 2015. Examples of AOP-informed model development and its application to the assessment of chemicals for skin sensitization and multiple modes of endocrine disruption are provided. The role of problem formulation, not only as a critical phase of risk assessment, but also as guide for both AOP and complementary model development is described. Finally, a proposal for actively engaging the modeling community in AOP-informed computational model development is made. The contents serve as a vision for how AOPs can be leveraged to facilitate development of computational prediction models needed to support the next generation of chemical safety assessment.

A Brief History of Immunotoxicology and a Review of the Pharmaceutical Guidelines

This article provides a brief history of the development of the field of immunotoxicology from one individual perspective and separates the discussion into five phases: the methods development and validation phase; the compound testing phase; the many meetings and organization of the specialty section phase; the mechanistic studies phase; and the guidelines phase. During the discussion of each phase, major highlights, accomplishments, contributors and key references are provided. The immunotoxicology guidelines for the testing of pharmaceutical chemical entities across the three major geographic axes are also presented and compared, along with some of the concerns raised by industry with these guidelines. The mandatory requirement of functional tests represents the major concern and difference between the Committee of Proprietary Medicinal Products (CPMP) and the new Food and Drug Administration (FDA) guidance. The scientific basis for the recommendation of the functional tests proposed in the guidance documents based on National Institute of Environmental Health and Safety/National Toxicology Program (NIEHS/NTP)-sponsored studies is described. Experience at Sanofi-Synthelabo, with the testing of 29 new chemical drug entities developed across a broad range of therapeutic classes using this testing paradigm and functional tests to define their immunotoxic potential, yielded a low number of compounds (6.8%) that produced any abnormal reaction. The two positive compounds might have been anticipated based on their pharmacology.

Going GLP: Conducting Toxicology Studies in Compliance with Good Laboratory Practices

Good laboratory practice standards are US federal regulations enacted as part of the Federal Insecticide, Fungicide, and Rodenticide Act (40 CFR Part 160), the Toxic Substance Control Act (40 CFR Part 792), and the Good Laboratory Practice for Nonclinical Laboratory Studies (21 CFR Part 58) to support protection of public health in the areas of pesticides, chemicals, and drug investigations in response to allegations of inaccurate data acquisition. Essentially, good laboratory practices (GLPs) are a system of management controls for nonclinical research studies involving animals to ensure the uniformity, consistency, reliability, reproducibility, quality, and integrity of data collected as part of chemical (including pharmaceuticals) tests, from in vitro through acute to chronic toxicity tests. The GLPs were established in the United States in 1978 as a result of the Industrial Bio-Test Laboratory scandal which led to congressional hearings and actions to prevent fraudulent data reporting and collection. Although the establishment of infrastructure for GLPs compliance is labor-intensive and time-consuming, achievement and maintenance of GLP compliance ensures the accuracy of the data collected from each study, which is critical for defending results, advancing science, and protecting human and animal health. This article describes how and why those in the US Army Medical Department responsible for protecting the public health of US Army and other military personnel made the policy decision to have its toxicology laboratory achieve complete compliance with GLP standards, the first such among US Army laboratories. The challenges faced and how they were overcome are detailed.

Scientific and Regulatory Policy Committee Points to Consider Review: Inclusion of Reproductive and Pathology End Points for Assessment of Reproductive and Developmental Toxicity in Pharmaceutical Drug Development

Standard components of nonclinical toxicity testing for novel pharmaceuticals include clinical and anatomic pathology, as well as separate evaluation of effects on reproduction and development to inform clinical development and labeling. General study designs in regulatory guidances do not specifically mandate use of pathology or reproductive end points across all study types; thus, inclusion and use of these end points are variable. The Scientific and Regulatory Policy Committee of the Society of Toxicologic Pathology (STP) formed a Working Group to assess the current guidelines and practices on the use of reproductive, anatomic pathology, and clinical pathology end points in general, reproductive, and developmental toxicology studies. The Working Group constructed a survey sent to pathologists and reproductive toxicologists, and responses from participating organizations were collected through the STP for evaluation by the Working Group. The regulatory context, relevant survey results, and collective experience of the Working Group are discussed and provide the basis of each assessment by study type. Overall, the current practice of including specific end points on a case-by-case basis is considered appropriate. Points to consider are summarized for inclusion of reproductive end points in general toxicity studies and for the informed use of pathology end points in reproductive and developmental toxicity studies.

Report of an independent peer review of an acrylonitrile risk assessment

A peer review panel made up of experts in toxicology, epidemiology, cancer mode of action (MOA), cancer mechanisms, carcinogenicity, genotoxicity, dose–response, US Environmental Protection Agency (EPA) cancer and noncancer methods, pharmacokinetic modeling and acrylonitrile, met on 22–23 September 2003 in Cincinnati, OH. The purpose of the meeting was to provide an independent review of a risk assessment of acrylonitrile that had been prepared by the Acrylonitrile Group (AN Group). Toxicology Excellence for Risk Assessment (TERA) organized the peer review and selected the panel. The panel discussed the toxicity and epidemiology literature of acrylonitrile and MOA information, and reached conclusions regarding its MOA, weight of evidence (WOE) for carcinogenicity, preferred approach for dose-response assessment and risk values. This paper summarizes the discussion and conclusions of the panel regarding the acrylonitrile assessment. Subsequent to the peer review, the authors of the acrylonitrile assessment revised their report and the panel reviewed the revised report. A manuscript of the revised assessment is being published in Regulatory Toxicology and Pharmacology.

Society of Toxicologic Pathology Position on Histopathology Data Collection and Audit Trail: Compliance with 21 CFR Parts 58 and 11

The purpose of this paper is to discuss the requirement of the audit trail to track changes made to the histopathology data, in order to be compliant with the Code of Federal Regulations (CFR), Volume 21, for both Part 58 (Good Laboratory Practices [GLP]) and Part 11 (Electronic Records/Signatures).

The Emergence of Systematic Review in Toxicology

The Evidence-based Toxicology Collaboration hosted a workshop on "The Emergence of Systematic Review and Related Evidence-based Approaches in Toxicology," on November 21, 2014 in Baltimore, Maryland. The workshop featured speakers from agencies and organizations applying systematic review approaches to questions in toxicology, speakers with experience in conducting systematic reviews in medicine and healthcare, and stakeholders in industry, government, academia, and non-governmental organizations. Based on the workshop presentations and discussion, here we address the state of systematic review methods in toxicology, historical antecedents in both medicine and toxicology, challenges to the translation of systematic review from medicine to toxicology, and thoughts on the way forward. We conclude with a recommendation that as various agencies and organizations adapt systematic review methods, they continue to work together to ensure that there is a harmonized process for how the basic elements of systematic review methods are applied in toxicology.

Society of Toxicologic Pathology Position Paper on Pathology Image Data: Compliance with 21 CFR Parts 58 and 11

The Society of Toxicologic Pathology (STP) has developed the following recommendations for the use of pathology images in compliance with the Code of Federal Regulations (CFR), Volume 21, Part 58 (Good Laboratory Practices [GLP]) and Part 11 (Electronic Records/Signatures). These recommendations include: (1) based on current technologies and practices, pathology images (printed, electronic, or digital) used for data generation (e.g., to make a diagnosis or for morphometric analysis) are raw data that must be authenticated and archived; (2) authentication of an image may be done either by initialing and dating a print of the image or by specifically annotating the electronic image file in compliance with Part 11 regulations; (3) images used for raw data are subject to GLP procedures and controls in order to ensure data integrity including written Standard Operating Procedures, testing/validation of equipment, training of personnel, etc.; (4) validation and/or performance qualification of imaging systems used to support GLP studies must be documented and any exceptions to full validation/qualification must be described in the GLP Compliance Statement for the study; (5) images that are not used for data generation are illustrative images, are not raw data, and generally do not have to be archived; 6) illustrative images should not be used to re-evaluate or supersede the pathologist’s diagnosis.

Does GLP enhance the quality of toxicological evidence for regulatory decisions?

There is debate over whether the requirements of GLP are appropriate standards for evaluating the quality of toxicological data used to formulate regulations. A group promoting the importance of non-monotonic dose responses for endocrine disruptors contend that scoring systems giving primacy to GLP are biased against non-GLP studies from the literature and are merely record-keeping exercises to prevent fraudulent reporting of data from non-published guideline toxicology studies. They argue that guideline studies often employ insensitive species and outdated methods, and ignore the perspectives of subject-matter experts in endocrine disruption, who should be the sole arbiters of data quality. We believe regulatory agencies should use both non-GLP and GLP studies, that GLP requirements assure fundamental tenets of study integrity not typically addressed by journal peer-review, and that use of standardized test guidelines and GLP promotes consistency, reliability, comparability, and harmonization of various types of studies used by regulatory agencies worldwide. This debate suffers two impediments to progress: a conflation of different phases of study interpretation and levels of data validity, and a misleading characterization of many essential components of GLP and regulatory toxicology. Herein we provide clarifications critical for removing those impediments.

Use of mechanistic data in the IARC evaluations of the carcinogenicity of polychlorinated biphenyls and related compounds

The IARC Monographs are a series of scientific reviews that identify environmental factors that can increase the risk of cancer in humans. In its first part, the principles and procedures of the IARC Monographs evaluations are summarized. In a second part, we present the most recent IARC evaluation of polychlorinated biphenyls (PCBs) and polybrominated biphenyls (PBBs), performed in February 2013: PCBs and dioxin-like PCBs were both classified into group 1 "carcinogens," while PBBs were evaluated as "probably carcinogenic to humans" (group 2A). Noteworthy is that the relative contributions of different PCB congeners to the carcinogenicity of PCB mixtures are not known. The use of mechanistic data for the classification into a higher category is discussed in the context of the history of the consecutive evaluations of several related polychlorinated compounds.

A Standard of Knowledge for the Professional Practice of Toxicology

BACKGROUND

Employers, courts, and the general public judge the credibility of professionals based on credentials such as academic degrees, publications, memberships in professional organizations, board certifications, and professional registrations. However, the relevance and merit of these credentials can be difficult to determine objectively. Board certification can be a reliable indicator of proficiency if the certifying organization demonstrates, through regularly scheduled independent review, that its processes meet established standards and when a certificate holder is required to periodically demonstrate command of a body of knowledge that is essential to current professional practice.

OBJECTIVE

We report herein a current Standard of Knowledge in general toxicology compiled from the experience and opinions of 889 certified practicing professional toxicologists.

DISCUSSION

An examination is the most commonly used instrument for testing a certification candidate's command of the body of knowledge. However, an examination-based certification is only creditable when the body of knowledge, to which a certification examination tests, is representative of the current knowledge, skills, and capabilities needed to effectively practice at the professional level. Thus, that body of knowledge must be the current "Standard of Knowledge" for the profession, compiled in a transparent fashion from current practitioners of the profession.

CONCLUSION

This work was conducted toward ensuring the scientific integrity of the products produced by professional toxicologists.

The apparently very variable potency of the anti-depressant fluoxetine

The anti-depressant fluoxetine is widely present in the aquatic environment. Typical river concentrations are in the low ng/L range. Many ecotoxicity studies have assessed the effects of this pharmaceutical on a range of aquatic species. Some studies report that ng, or even pg, per litre concentrations cause effects, whereas other studies report that effects only occur when the water concentration is in the μg/L range. It seems unlikely that all reported effects will be repeatable. Many of the studies have considerable limitations. Currently it is impossible to ascertain what environmental concentrations of fluoxetine pose a risk to aquatic organisms. The key question can be answered only by high quality, reproducible research.

Best practices for the development, scale-up, and post-approval change control of IR and MR dosage forms in the current quality-by-design paradigm

In this whitepaper, the Manufacturing Technical Committee of the Product Quality Research Institute provides information on the common, best practices in use today in the development of high-quality chemistry, manufacturing and controls documentation. Important topics reviewed include International Conference on Harmonization, in vitro-in vivo correlation considerations, quality-by-design approaches, process analytical technologies and current scale-up, and process control and validation practices. It is the hope and intent that this whitepaper will engender expanded dialog on this important subject by the pharmaceutical industry and its regulatory bodies.

The holy grail in genetic toxicology: follow-up approaches for positive results in the Ames assay

Positive results in the Ames/E. coli bacterial mutagenicity assay create a significant hurdle for the development of new products/drugs and as a result, most companies drop mutagenic ingredients from further development. One important consequence of this is that the understanding of the human relevance of chemicals that are positive in the Ames assay is not increasing at the pace seen with ingredients that are positive in the other in vitro genotoxicity assays. Recent advances in defining thresholds for mutagenic carcinogens, along with new assays for measuring mutagenicity in vivo suggests it is time to direct more attention to the holy grail of clearly defining practical approaches to address positive results in the Ames assay. To stimulate further discussion and research in this area, a review of the most current thinking on approaches for dealing with Ames positive results is provided along with some suggestions for the way forward.

Transparency and translation of science in a modern world

The co-Editors-in-Chief of Environmental Health respond to an unusual initiative taken by editors of 14 toxicology journals to influence pending decisions by the European Commission to establish a framework for regulating chemicals that pose a hazard to normal function of the endocrine system. This initiative is also the subject of this Commentary in this journal by authors who recently reviewed the subject and who point out inaccuracies in the toxicology editors' critique. The dispute is about potential public policy development, rather than on science translation and research opportunities and priorities. The toxicology journal editors recommend that chemicals be examined in depth one by one, ignoring modern achievements in biomedical research that would allow new understanding of the effects of classes of toxic substances in complex biological systems. Concerns about policy positions framed as scientific ones are especially important in a time with shrinking public support for biomedical research affects priorities. In such a setting, conflict of interest declarations are important, especially in research publications that address issues of public concern and where financial and other interests may play a role. Science relies on trust, and reasonable disclosure of financial or other potential conflicts is therefore essential. This need has been emphasized by recent discoveries of hidden financial conflicts in publications in toxicology journals, thus misleading readers and the public about the safety of particular industrial products. The transparency provided by Environmental Health includes open access and open peer review, with reader access to reviews, including the identity of reviewers and their statements on possible conflicts of interest. However, the editors of the 14 toxicology journals did not provide any information on potential conflicts of interest, an oversight that needs to be corrected.

Science and policy on endocrine disrupters must not be mixed: a reply to a "common sense" intervention by toxicology journal editors

The "common sense" intervention by toxicology journal editors regarding proposed European Union endocrine disrupter regulations ignores scientific evidence and well-established principles of chemical risk assessment. In this commentary, endocrine disrupter experts express their concerns about a recently published, and is in our considered opinion inaccurate and factually incorrect, editorial that has appeared in several journals in toxicology. Some of the shortcomings of the editorial are discussed in detail. We call for a better founded scientific debate which may help to overcome a polarisation of views detrimental to reaching a consensus about scientific foundations for endocrine disrupter regulation in the EU.

Misuse of the Naranjo Adverse Drug Reaction Probability Scale in toxicology

CONTEXT

When an adverse event occurs in an overdose patient, it may be difficult to determine whether the event was caused by the ingested drug or by medical therapy. Naranjo et al. developed a probability scale, the Naranjo Adverse Drug Reaction Probability Scale (Naranjo Scale), to assess the probability that a drug administered in therapeutic doses caused an adverse event thereby classifying the event as an adverse drug reaction (ADR). Although Naranjo et al. specifically excluded the application of this scale to adverse events in overdose patients, case reports demonstrate that authors continue to apply the Naranjo Scale to events in these patients.

OBJECTIVE

The World Health Organization defines an ADR as occurring only when drugs are administered in therapeutic doses. Yet ADRs continue to be reported in overdose patients. We sought to examine the use of the Naranjo scale in case reports of overdose patients to assess the potential consequences of that application.

METHODS

A Medline search via PubMed without language limits, through September 2012, using the search terms "Naranjo" and "overdose" or "poisoning" yielded 146 publications. Additional searches were performed to find articles with keywords of the Naranjo Scale development, current applications and validity of application in specific populations such as critically ill and overdose patients.

RESULTS

From the 146 publications, we identified 17 case reports or case series of overdose patients in which the Naranjo Scale was applied to a clinical complication to support a causal relationship between an administered drug and the clinical complication and thereby classify the clinical complication as an ADR. We also identified a recent publication in which the Naranjo Scale was applied to a new treatment modality (lipid emulsion) that is currently administered to overdose patients. Original publication of the Naranjo Scale and studies evaluating its use in critically ill patients or those with drug-induced disease were also retrieved.

CONCLUSION

Adverse events that occur in overdose patients are excluded from the definition of ADR. Yet in case reports or series of overdose patients, the Naranjo Scale has been applied to assess the probability an event was caused by the ingested drug or therapeutic modality. This application of the Naranjo Scale is not scientifically valid and may lead to erroneous conclusions. There is no evidence to support the application of the Naranjo scale to any events that occur in overdose patients.

Risk assessment of nanomaterials in cosmetics: a European union perspective

In Europe, the data requirements for the hazard and exposure characterisation of chemicals are defined according to the REACH regulation and its guidance on information requirements and chemical safety assessment (Regulation (EC) No 1907/2006 of the European Parliament and of the Council of 18 December 2006 concerning the Registration, Evaluation, Authorisation and Restriction of Chemicals (REACH), and its guidance documents; available at: http://eur-lex.europa.eu/LexUriServ/LexUriServ.do?uri=OJ:L:2006:396:0001:0849:EN:PDF ; and at: http://guidance.echa.europa.eu/docs/guidance_document/information_requirements_en.htm ). This is the basis for any related risk assessment. The standard reference for the testing of cosmetic ingredients is the SCCP's 'Notes of Guidance for the Testing of Cosmetic Ingredients and their Safety Evaluation' (The SCCP's Notes of Guidance for the testing of cosmetic ingredients and their safety evaluation (2006); available at: http://ec.europa.eu/health/ph_risk/committees/04_sccp/docs/sccp_o_03j.pdf ), which refers to the OECD guidelines for the testing of chemicals (The OECD Guidelines for the Testing of Chemicals as a collection of the most relevant internationally agreed testing methods used by government, industry and independent laboratories to assess the safety of chemical products; available at: http://www.oecd.org/topic/0,2686,en_2649_34377_1_1_1_1_37407,00.html ). According to the cosmetics directive [76/768/EEC], compounds that are classified as mutagenic, carcinogenic or toxic to reproduction are banned for the use in cosmetic products. Since December 2010, the respective labelling is based on the rules of regulation (EC) No. 1272/2008 (Regulation (EC) No 1272/2008 of the European Parliament and of the Council of 16 December 2008 on classification, labelling and packaging of substances and mixtures, amending and repealing Directives 67/548/EEC and 1999/45/EC, and amending Regulation (EC) No 1907/2006, Official Journal L 353, 31/12/2008, pages 1-1355; available at: http://eur-lex.europa.eu/LexUriServ/LexUriServ.do?uri=OJ:L:2008:353:0001:1355:en:PDF ) on classification, labelling and packaging of substances and mixtures (CLP). There is no further impact from the CLP regulation on cosmetic products, because regulation (EC) No. 1223/2009 on cosmetic products defines its own labelling rules (Regulation (EC) No 1223/2009 of the European Parliament and of the Council of 30 November 2009 on cosmetic products; available at: http://eur-lex.europa.eu/LexUriServ/LexUriServ.do?uri=OJ:L:2009:342:0059:0209:en:PDF ). Special notification procedures are mandatory for preservatives, colourants and UV-filters where a safety approval from the European 'Scientific Committee on Consumer Safety' (SCCS) is needed prior to marketing. The risk assessment of nanomaterials in consumer products still poses a significant challenge as highlighted by the example of UV-filters in sunscreens since nanomaterials cannot be classified as a homogenous group of chemicals but still need to be addressed in risk characterisation on a case by case basis.

The fundamental role of morphology in experimental neurotoxicology: the example of chemotherapy-induced peripheral neurotoxicity

The peripheral nervous system is a frequent target of toxic agents. The accurate identification of the sites of neurotoxic action through the morphological characterization of reliable in vivo models or in vitro systems can give fundamental clues when investigating the pathogenesis and interpreting the clinical features of drug-induced neuropathy. The morphological approach has been used to investigate almost all the anticancer drugs able to induce chemotherapy-induced peripheral neurotoxicity, i.e. platinum drugs, antitubulins and proteasome inhibitors. No models have ever been described for thalidomide. This review demonstrates that any pathogenetic study on chemotherapy-induced peripheral neurotoxicity must be based on solid morphological observations obtained in reliable animal and in vitro models. This is particularly true in this setting, since the availability of tissues of human origin is extremely limited. In fact, peripheral (generally sural) nerve biopsies are never required for diagnostic purposes in chemotherapy-treated cancer patients, and their use for a purely scientific aim, although potentially very informative, is not ethical. Moreover, several neurotoxic drugs target the dorsal root ganglia neurons, and it is very difficult to obtain high-quality specimens even from early autopsies. It is, therefore, our opinion that an extensive morphological assessment of the in vitro and in vivo effect of any potentially neurotoxic antineoplastic drugs, as well as of neuroprotectant agents, should be taken into consideration right from the earliest stages of their development.