Practical considerations for developmental thyroid toxicity assessments: What's working, what's not, and how can we do better?

Publication date: Available online 21 April 2019Source: Regulatory Toxicology and PharmacologyAuthor(s): Abby A. Li, Susan L. Makris, M. Sue Marty, Volker Strauss, Mary Gilbert, Ann Blacker, Leah M. Zorrilla, Pragati S. Coder, Bethany Hannas, Sheri Lordi, Steffen SchneiderAbstractThyroid hormones (THs; T3 and T4) play a role in development of cardiovascular, reproductive, immune and nervous systems. Thus, interpretation of TH changes from rodent studies (during pregnancy, in fetuses, neonates, and adults) is critical in hazard characterization and risk assessment. A roundtable session at the 2017 Society of Toxicology (SOT) meeting brought together academic, industry and government scientists to share knowledge and different perspectives on technical and data interpretation issues. Data from a limited group of laboratories were compiled for technical discussions on TH measurements, including good practices for reliable serum TH data. Inter-laboratory historical control data, derived from immunoassays or mass spectrometry methods, revealed: 1) assay sensitivities vary within and across methodologies; 2) TH variability is similar across animal ages; 3) laboratories generally achieve sufficiently sensitive TH quantitation levels, although issues remain for lower levels of serum TH and TSH in fetuses and postnatal day 4 pups; thus, assay sensitivity is critical at these life stages. Best practices require detailed validation of rat serum TH measurements across ages to establish a...
Source: Regulatory Toxicology and Pharmacology - Category: Toxicology Source Type: research