RESUMEN
This is Part II of a review covering the wide range of issues associated with all aspects of the use and responsible disposal of foam and plastic wastes containing toxic or potentially toxic flame retardants. We identify basic and applied research needs in the areas of responsible collection, pretreatment, processing, and management of these wastes. In Part II, we explore alternative technologies for the management of halogenated flame retardant (HFR) containing wastes, including chemical, mechanical, and thermal processes for recycling, treatment, and disposal.
RESUMEN
Flame retardants (FRs) are added to foams and plastics to comply with flammability standards and test requirements in products for household and industrial uses. When these regulations were implemented, potential health and environmental impacts of FR use were not fully recognized or understood. Extensive research in the past decades reveal that exposure to halogenated FRs, such as those used widely in furniture foam, is associated with and/or causally related to numerous health effects in animals and humans. While many of the toxic FRs have been eliminated and replaced by other FRs, existing products containing toxic or potentially toxic chemical FRs will remain in use for decades, and new products containing these and similar chemicals will permeate the environment. When such products reach the end of their useful life, proper disposal methods are needed to avoid health and ecological risks. To minimize continued human and environmental exposures to hazardous FR chemicals from discarded products, waste management technologies and processes must be improved. This review discusses a wide range of issues associated with all aspects of the use and responsible disposal of wastes containing FRs, and identifies basic and applied research needs in the areas of responsible collection, pretreatment, processing, and management of these wastes.
RESUMEN
The Florence Statement on Triclosan and Triclocarban documents a consensus of more than 200 scientists and medical professionals on the hazards of and lack of demonstrated benefit from common uses of triclosan and triclocarban. These chemicals may be used in thousands of personal care and consumer products as well as in building materials. Based on extensive peer-reviewed research, this statement concludes that triclosan and triclocarban are environmentally persistent endocrine disruptors that bioaccumulate in and are toxic to aquatic and other organisms. Evidence of other hazards to humans and ecosystems from triclosan and triclocarban is presented along with recommendations intended to prevent future harm from triclosan, triclocarban, and antimicrobial substances with similar properties and effects. Because antimicrobials can have unintended adverse health and environmental impacts, they should only be used when they provide an evidence-based health benefit. Greater transparency is needed in product formulations, and before an antimicrobial is incorporated into a product, the long-term health and ecological impacts should be evaluated. https://doi.org/10.1289/EHP1788.
Asunto(s)
Antiinfecciosos/análisis , Carbanilidas/análisis , Disruptores Endocrinos/análisis , Contaminantes Ambientales/análisis , Triclosán/análisis , Cosméticos , Exposición a Riesgos Ambientales , Política AmbientalRESUMEN
The interaction of the metal and support in oxide-supported transition-metal catalysts has been proven to have extremely favorable effects on catalytic performance. Herein, mesoporous Co3O4, NiO, MnO2, Fe2O3, and CeO2 were synthesized and utilized in CO oxidation reactions to compare the catalytic activities before and after loading of 2.5 nm Pt nanoparticles. Turnover frequencies (TOFs) of pure mesoporous oxides were 0.00020.015 s(1), while mesoporous silica was catalytically inactive in CO oxidation. When Pt nanoparticles were loaded onto the oxides, the TOFs of the Pt/metal oxide systems (0.1500 s(1)) were orders of magnitude greater than those of the pure oxides or the silica-supported Pt nanoparticles. The catalytic activities of various Pt/oxide systems were further influenced by varying the ratio of CO and O2 in the reactant gas feed, which provided insight into the mechanism of the observed support effect. In situ characterization using near-edge X-ray absorption fine structure (NEXAFS) and ambient-pressure X-ray photoelectron spectroscopy (APXPS) under catalytically relevant reaction conditions demonstrated a strong correlation between the oxidation state of the oxide support and the catalytic activity at the oxidemetal interface. Through catalytic activity measurements and in situ X-ray spectroscopic probes, CoO, Mn3O4, and CeO2 have been identified as the active surface phases of the oxide at the interface with Pt nanoparticles.