Regulatory Toxicology and Pharmacology : RTP This is an RSS file. You can use it to subscribe to this data in your favourite RSS reader or to display this data on your own website or blog.

Considerations for the development of guidance on dose level selection for developmental and reproductive toxicity studies
Regul Toxicol Pharmacol. 2024 Feb 23:105585. doi: 10.1016/j.yrtph.2024.105585. Online ahead of print.ABSTRACTIn 2022, the European Chemicals Agency issued advice on the selection of high dose levels for developmental and reproductive toxicity (DART) studies indicating that the highest dose tested should aim to induce clear evidence of reproductive toxicity without excessive toxicity and severe suffering in parental animals. In addition, a recent publication advocated that a 10% decrease in body weight gain should be replaced with a 10% decrease in bodyweight as a criterion for dose adequacy. Experts from the European Centr...
Source: Regulatory Toxicology and Pharmacology : RTP - February 25, 2024 Category: Toxicology Authors: R W Lewis A K Andrus J Arroyo S Brescia P A Botham M Corvaro G P Daston T Hofmann C Rodriguez F Sewell B van Ravenzwaay K Wiench S Marty Source Type: research

The role of trust in the use of artificial intelligence for chemical risk assessment
Regul Toxicol Pharmacol. 2024 Feb 23:105589. doi: 10.1016/j.yrtph.2024.105589. Online ahead of print.ABSTRACTRisk assessment of chemicals is a time-consuming process and needs to be optimized to ensure all chemicals are timely evaluated and regulated. This transition could be stimulated by valuable applications of in silico Artificial Intelligence (AI)/Machine Learning (ML) models. However, implementation of AI/ML models in risk assessment is lagging behind. Most AI/ML models are considered 'black boxes' that lack mechanistical explainability, causing risk assessors to have insufficient trust in their predictions. Here, we...
Source: Regulatory Toxicology and Pharmacology : RTP - February 25, 2024 Category: Toxicology Authors: Pim N H Wassenaar Jordi Minnema Jelle Vriend Willie J G M Peijnenburg Jeroen L A Pennings Anne Kienhuis Source Type: research

In vivo alkaline comet assay: Statistical considerations on historical negative and positive control data
Regul Toxicol Pharmacol. 2024 Feb 22;148:105583. doi: 10.1016/j.yrtph.2024.105583. Online ahead of print.ABSTRACTThe alkaline comet assay is frequently used as in vivo follow-up test within different regulatory environments to characterize the DNA-damaging potential of different test items. The corresponding OECD Test guideline 489 highlights the importance of statistical analyses and historical control data (HCD) but does not provide detailed procedures. Therefore, the working group "Statistics" of the German-speaking Society for Environmental Mutation Research (GUM) collected HCD from five laboratories and >200 comet ...
Source: Regulatory Toxicology and Pharmacology : RTP - February 24, 2024 Category: Toxicology Authors: Timur Tug Julia C Duda Max Menssen Shannon Wilson Bruce Frank Bringezu Martina Dammann Roland Fr ötschl Volker Harm Katja Ickstadt Bernd-Wolfgang Igl Marco Jarzombek Rupert Kellner Jasmin Lott Stefan Pfuhler Ulla Plappert-Helbig J örg Rahnenführer Mark Source Type: research

Replacing concurrent controls with virtual control groups in rat toxicity studies
Regul Toxicol Pharmacol. 2024 Feb 22:105592. doi: 10.1016/j.yrtph.2024.105592. Online ahead of print.ABSTRACTVirtual control groups (VCGs) in nonclinical toxicity represent the concept of using appropriate historical control data for replacing concurrent control group animals. Historical control data collected from standardized studies can serve as base for constructing VCGs and legacy study reports can be used as a benchmark to evaluate the VCG performance. Replacing concurrent controls of legacy studies with VCGs should ideally reproduce the results of these studies. Based on three four-week rat oral toxicity legacy stud...
Source: Regulatory Toxicology and Pharmacology : RTP - February 24, 2024 Category: Toxicology Authors: Alexander Gurjanov Carlos Vieira-Vieira Julia Vienenkoetter Lea A I Vaas Thomas Steger-Hartmann Source Type: research

Sensory irritation and use of the best available science in setting exposure limits: Issues raised by a scientific panel review of formaldehyde human research studies
Regul Toxicol Pharmacol. 2024 Feb 21:105587. doi: 10.1016/j.yrtph.2024.105587. Online ahead of print.ABSTRACTAs a high production volume chemical with recognized sensory irritation and widespread exposure, the human health risk potential of formaldehyde has been reviewed by many international regulatory agencies and scientific advisory bodies. A scientific panel, the Human Studies Review Board, under the auspices of the EPA's Toxic Substances Control Act (TSCA) program recently reviewed the sensory irritation studies included in the 2022 Draft Integrated Risk Information System (IRIS) Formaldehyde Hazard Assessment in the ...
Source: Regulatory Toxicology and Pharmacology : RTP - February 23, 2024 Category: Toxicology Authors: Katy Goyak Stewart Holm Source Type: research

Genotoxicity evaluation of food additive titanium dioxide using a battery of standard in vivo tests
Regul Toxicol Pharmacol. 2024 Feb 19:105586. doi: 10.1016/j.yrtph.2024.105586. Online ahead of print.ABSTRACTThe increasing use of titanium dioxide (TiO2) nanoparticles (NPs) has raised concern about the safety of food additive TiO2. TiO2 has been considered no longer safe by EFSA due to concerns over genotoxicity, however, there are conflicting opinions upon the safety of TiO2 as a food additive, and the number of in vivo genotoxicity studies conducted on food additive TiO2 was limited. In order to investigate the the potential genotoxicity of food additive TiO2, we evaluated the genotoxicity of a commercial food additive...
Source: Regulatory Toxicology and Pharmacology : RTP - February 21, 2024 Category: Toxicology Authors: None Chunlai Liang Xiaopeng Zhang Jin Fang Nana Sun Haibo Liu Yongquan Feng Huali Wang Zhou Yu Xudong Jia Source Type: research

Repeat dose and reproductive toxicity of thrombopoietin mimic peptide in Sprague-Dawley rats
In this report, we evaluated the potential toxicity of TMP in repeat-dose toxicity and reproductive/developmental toxicity studies (segment Ⅰ, Ⅱ, Ⅲ). TMP was administered subcutaneously to Sprague-Dawley (SD) rats at 5, 15 or 50 mcg/kg. In repeat-dose toxicity study, the rats were administrated three times a week for 26 week with a 4-week recovery. TMP could produce anti-drug antibodies and induce platelet counts increase, megakaryocyte proliferation. While platelet counts decreased gradually and returned to normal after 4 weeks in male rats. Other significant findings included myelofibrosis of bone marrow, hepatic e...
Source: Regulatory Toxicology and Pharmacology : RTP - February 11, 2024 Category: Toxicology Authors: Shidong Qiu Yuji Liang Xiaobo Wang Xiue Li Guoyue Wei Peng Xiao Suling Teng Peilu Sun Lei Song Zenglin Zhao Yanling Mu Source Type: research

Chronic aquatic toxicity assessment of diverse chemicals on Daphnia magna using QSAR and chemical read-across
Regul Toxicol Pharmacol. 2024 Feb 5;148:105572. doi: 10.1016/j.yrtph.2024.105572. Online ahead of print.ABSTRACTWe have modeled here chronic Daphnia toxicity taking pNOEC (negative logarithm of no observed effect concentration in mM) and pEC50 (negative logarithm of half-maximal effective concentration in mM) as endpoints using QSAR and chemical read-across approaches. The QSAR models were developed by strictly obeying the OECD guidelines and were found to be reliable, predictive, accurate, and robust. From the selected features in the developed models, we have found that an increase in lipophilicity and saturation, the pr...
Source: Regulatory Toxicology and Pharmacology : RTP - February 7, 2024 Category: Toxicology Authors: Ankur Kumar Vinay Kumar Probir Kumar Ojha Kunal Roy Source Type: research