RESUMEN
High-resolution mass spectrometry was used to screen for emerging per- and polyfluorinated alkyl substances (PFAS) in precipitation samples collected in summer 2019 at seven sites in the United States. We previously quantified the concentration of ten PFAS in the rainwater samples using the method of isotopic dilution (Pike et al., 2021). Nine of these targeted analytes belonged to the U.S. Environmental Protection Agency Regional Screening Level list, herein referred to as EPA-monitored analytes. In this new work, we identify emerging PFAS compounds by liquid chromatography quadrupole time-of-flight mass spectrometry. Several emerging PFAS were detected across all samples, with the most prevalent compounds being C3-C8 hydrogen-substituted perfluorocarboxylic acids (H-PFCAs) and fluorotelomer carboxylic acids (FTCAs). Concentrations of emerging PFAS were in the 10-1000 ng L-1 range (approximately 1-2 orders of magnitude greater than EPA-monitored PFAS) at all sites except Wooster, OH, where concentrations were even higher, with a maximum estimated ΣPFAS of 16 400 ng L-1. The elevated levels of emerging PFAS in the Wooster samples were predominantly even and odd chain-length H-PFCAs and FTCAs comprised of complex mixtures of branched isomers. This unique composition did not match any known manufactured PFAS formulation reported to date, but it could represent thermally transformed by-products emitted by a local point source. Overall, the results indicate that PFAS outside of the standard analyte lists make up a significant and previously unappreciated fraction of contaminants in rainwater collected within the central U.S.-and potentially world-wide-especially in proximity to localized point sources.
Asunto(s)
Fluorocarburos , Contaminantes Químicos del Agua , Estados Unidos , Fluorocarburos/análisis , Monitoreo del Ambiente/métodos , Cromatografía Liquida , Espectrometría de Masas , Ácidos Carboxílicos/análisis , Contaminantes Químicos del Agua/análisisRESUMEN
Stringent nonpharmaceutical interventions (NPIs) such as lockdowns and border closures are not currently recommended for pandemic influenza control. New Zealand used these NPIs to eliminate coronavirus disease 2019 during its first wave. Using multiple surveillance systems, we observed a parallel and unprecedented reduction of influenza and other respiratory viral infections in 2020. This finding supports the use of these NPIs for controlling pandemic influenza and other severe respiratory viral threats.
Asunto(s)
COVID-19/epidemiología , Gripe Humana/epidemiología , Infecciones del Sistema Respiratorio/epidemiología , COVID-19/prevención & control , COVID-19/virología , Control de Enfermedades Transmisibles , Monitoreo Epidemiológico , Hospitalización/estadística & datos numéricos , Humanos , Gripe Humana/prevención & control , Gripe Humana/virología , Nueva Zelanda/epidemiología , Pandemias , Salud Pública , Infecciones del Sistema Respiratorio/prevención & control , Infecciones del Sistema Respiratorio/virología , SARS-CoV-2/aislamiento & purificaciónRESUMEN
Stringent nonpharmaceutical interventions (NPIs) such as lockdowns and border closures are not currently recommended for pandemic influenza control. New Zealand used these NPIs to eliminate coronavirus disease 2019 during its first wave. Using multiple surveillance systems, we observed a parallel and unprecedented reduction of influenza and other respiratory viral infections in 2020. This finding supports the use of these NPIs for controlling pandemic influenza and other severe respiratory viral threats.