Contaminated water and food are the main sources of documented per- and polyfluoroalkyl substances (PFAS) exposure in humans. However, other sources may contribute to the overall PFAS intake. While several studies documented the presence of PFAS in consumer products, PFAS evaluation in dental products has been limited to floss and tape to date.
View Article and Find Full Text PDFThe potential for polycyclic aromatic hydrocarbons (PAHs) to have adverse effects that persist across generations is an emerging concern for human and wildlife health. This study evaluated the role of mitochondria, which are maternally inherited, in the cross-generational toxicity of benzo(a)pyrene (BaP), a model PAH and known mitochondrial toxicant. Mature female zebrafish (F0) were fed diets containing 0, 12.
View Article and Find Full Text PDFRegul Toxicol Pharmacol
October 2023
Propylene dichloride (PDC) is a chlorinated substance used primarily as an intermediate in basic organic chemical manufacturing. The United States Environmental Protection Agency (EPA) is currently evaluating PDC as a high-priority substance under the Toxic Substances Control Act (TSCA). We conducted a systematic review of the non-cancer and cancer hazards of PDC using the EPA TSCA and Integrated Risk Information System (IRIS) frameworks.
View Article and Find Full Text PDFChem Biol Interact
September 2023
As part of a systematic review of the non-cancer and cancer hazards of propylene dichloride (PDC), with a focus on potential carcinogenicity in workers following inhalation exposures, we determined that a mode of action (MOA)-centric framing of cancer effects was warranted. In our MOA analysis, we systematically reviewed the available mechanistic evidence for PDC-induced carcinogenesis, and we mapped biologically plausible MOA pathways and key events (KEs), as guided by the International Programme on Chemical Safety (IPCS)-MOA framework. For the identified pathways and KEs, biological concordance, essentiality of KEs, concordance of empirical observations among KEs, consistency, and analogy were evaluated.
View Article and Find Full Text PDFEthylene oxide is a highly reactive chemical primarily used as an intermediate in chemical production and as a sterilant of medical equipment and food products; it also is produced endogenously as a result of physiological processes. We conducted a systematic review of the potential carcinogenicity of inhaled ethylene oxide in humans using methods that adhere to PRIMSA guidelines and that incorporate aspects from the Institute of Medicine (IOM) (now the National Academy of Medicine) as well as several US Environmental Protection Agency (EPA) frameworks for systematic reviews. After a comprehensive literature search and selection process, study quality was evaluated following a method adapted from the EPA Toxic Substances Control Act (TSCA) framework.
View Article and Find Full Text PDFBackground: Limited safety information has been described in the peer-reviewed literature for callus-softening products containing potassium hydroxide.
Methods: This pilot human use study evaluated the safety and effectiveness of a commercially available callus softener, containing less than 10% potassium hydroxide by weight. Baseline callused skin was scored (grade 1-4) on each study participant's feet (n = 10).
The International Agency for Research on Cancer (IARC) and the United States Environmental Protection Agency (USEPA) classified ethylene oxide (EtO) as a known human carcinogen. Critically, both noted that the epidemiological evidence based on lymphoid and breast cancers was "limited," but that the evidence in animal studies was "sufficient" and "extensive" (respectively) and that EtO is genotoxic. The USEPA derived one of the highest published inhalation unit risk (IUR) values (3 × 10 per [µg/m EtO]), based on results from 2 epidemiological studies.
View Article and Find Full Text PDFPlastic pollution is a critical environmental concern and comprises the majority of anthropogenic debris in the ocean, including macro, micro, and likely nanoscale (less than 100nm in at least one dimension) plastic particles. While the toxicity of macroplastics and microplastics is relatively well studied, the toxicity of nanoplastics is largely uncharacterized. Here, fluorescent polystyrene nanoparticles (PS NPs) were used to investigate the potential toxicity of nanoplastics in developing zebrafish (Danio rerio), as well as to characterize the uptake and distribution of the particles within embryos and larvae.
View Article and Find Full Text PDFEnviron Toxicol Pharmacol
September 2017
Zebrafish are an attractive model organism for toxicology; however, an important consideration in translating between species is xenobiotic metabolism/bioactivation. CYP2E1 metabolizes small hydrophobic molecules, e.g.
View Article and Find Full Text PDFSeveral xenobiotic agents (e.g. metals, polycyclic aromatic hydrocarbons, nanoparticles, etc.
View Article and Find Full Text PDFOrganismal metabolic rate, a fundamental metric in biology, demonstrates an allometric scaling relationship with body size. Fractal-like vascular distribution networks of biological systems are proposed to underlie metabolic rate allometric scaling laws from individual organisms to cells, mitochondria, and enzymes. Tissue-specific metabolic scaling is notably absent from this paradigm.
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