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Polybrominated diphenyl ethers (PBDEs), previously incorporated in a wide variety of common products, can now be found throughout the environment. Because of their environmental persistence and the potential health hazards they pose to humans and wildlife, they have been added to the Stockholm Convention on Persistent Organic Pollutants, and they continue to be of significant concern. We report herein the first application of a nanocomposite catalyst consisting of a m -BiVO 4 /BiOBr heterojunction surface-decorated with Pd nanoparticles in the photocatalytic reductive debromination of PBDEs using visible light. Specifically, this system demonstrated both rapid and complete debromination of 2,2′,4,4′-tetrabromodiphenyl ether (BDE-47), with an exceedingly large initial pseudo-first-order rate constant of 1.33 min −1 . Analysis of the reaction mechanism identified the stepwise degradation pathway to generate the final diphenyl ether product as well as the role of the alcohol-based sacrificial reagent. Such information provides routes towards new approaches for environmental remediation by identifying reaction pathways for common organic pollutants that remain challenging to degrade via sustainable methods.
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Global marine pollutants inhibit P-glycoprotein: Environmental levels, inhibitory effects, and cocrystal structure
The world’s oceans are a global reservoir of persistent organic pollutants to which humans and other animals are exposed. Although it is well known that these pollutants are potentially hazardous to human and environmental health, their impacts remain incompletely understood. We examined how persistent organic pollutants interact with the drug efflux transporter P-glycoprotein (P-gp), an evolutionarily conserved defense protein that is essential for protection against environmental toxicants. We identified specific congeners of organochlorine pesticides, polychlorinated biphenyls, and polybrominated diphenyl ethers that inhibit mouse and human P-gp, and determined their environmental levels in yellowfin tuna from the Gulf of Mexico. In addition, we solved the cocrystal structure of P-gp bound to one of these inhibitory pollutants, PBDE (polybrominated diphenyl ether)–100, providing the first view of pollutant binding to a drug transporter. The results demonstrate the potential for specific binding and inhibition of mammalian P-gp by ubiquitous congeners of persistent organic pollutants present in fish and other foods, and argue for further consideration of transporter inhibition in the assessment of the risk of exposure to these chemicals.
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- Award ID(s):
- 1314480
- PAR ID:
- 10098784
- Date Published:
- Journal Name:
- Science Advances
- Volume:
- 2
- Issue:
- 4
- ISSN:
- 2375-2548
- Page Range / eLocation ID:
- e1600001
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1126/sciadv.1600001
