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1.
Sci Total Environ ; 408(20): 4591-9, 2010 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-20627203

RESUMEN

From research on PM(2.5) and PM(10) in 2007/2008 in the Netherlands, it was concluded that the coarse fraction (PM(2.5-10)) attributed 60% and 50% respectively, to the urban-regional and street-urban increments of PM(10). Contrary to Scandinavian and Mediterranean countries which exhibit significant seasonal variation in the coarse fraction of particulate matter (PM), in the Netherlands the coarse fraction in PM at a street location is rather constant during the year. Non-exhaust emissions by road traffic are identified as the main source for coarse PM in urban areas. Non-exhaust emissions mainly originate from re-suspension of accumulated deposited PM and road wear related particles, while primary tire and brake wear hardly contribute to the mass of non-exhaust emissions. However, tire and brake wear can clearly be identified in the total mass through the presence of the heavy metals: zinc, a tracer for tire wear and copper, a tracer for brake wear. The efficiency of road sweeping and washing to reduce non-exhaust emissions in a street-canyon in Amsterdam was investigated. The increments of the coarse fraction at a kerbside location and a housing façade location versus the urban background were measured at days with and without sweeping and washing. It was concluded that this measure did not significantly reduce non-exhaust emissions.


Asunto(s)
Contaminantes Atmosféricos/análisis , Restauración y Remediación Ambiental/métodos , Material Particulado/análisis , Contaminación del Aire/estadística & datos numéricos , Eficiencia , Monitoreo del Ambiente , Vehículos a Motor , Países Bajos , Tamaño de la Partícula
2.
Environ Toxicol Chem ; 26(5): 898-907, 2007 May.
Artículo en Inglés | MEDLINE | ID: mdl-17521135

RESUMEN

The exposure to and effects of estrogenic compounds in male breams from Dutch freshwater locations were investigated. Ovotestis was observed infrequently (maximum frequency 16%). However, plasma vitellogenin (VTG) concentration was elevated highly at some locations. Estrogenic activities in male bream plasma, liver, and in gastrointestinal content were measured in the estrogen-responsive chemical-activated luciferase gene expression (ER-CALUX) assay. Plasma concentrations of vitellogenin correlated very well with the estrogenic activities in gastrointestinal content. The ER-CALUX activity in gastrointestinal content thus could provide a biomarker for recent exposure to estrogenic compounds, and the gastrointestinal content was chosen as investigative matrix for the toxicity identification and evaluation ([TIE]; bioassay-directed fractionation) of estrogenic compounds in bream. The approach consisted of a reversed-phase high-performance liquid chromatography fractionation of gastrointestinal content extract, directed by ER-CALUX and followed by gas chromatography analysis. The estrogenic hormones 17beta-estradiol and its metabolite estrone were identified as major contributors to the activity at all locations (except the reference location), independent of the presence or absence of a known source of estrogenic activity, such as a sewage treatment plant. Chemical screening showed the presence of other pollutants, such as a lower chlorinated dioxin and the disinfectants clorophene and triclosan. However, these compounds did not have high estrogenic potencies and their concentrations were not high enough to contribute significantly to the observed estrogenic activity.


Asunto(s)
Bioensayo , Monitoreo del Ambiente , Estrógenos/metabolismo , Dorada/metabolismo , Contaminantes Químicos del Agua/metabolismo , Animales , Cromatografía Líquida de Alta Presión , Diclorofeno/análogos & derivados , Diclorofeno/análisis , Diclorofeno/metabolismo , Diclorofeno/toxicidad , Dioxinas/análisis , Dioxinas/metabolismo , Dioxinas/toxicidad , Desinfectantes/análisis , Desinfectantes/metabolismo , Desinfectantes/toxicidad , Estradiol/análisis , Estradiol/metabolismo , Estradiol/toxicidad , Estrógenos/análisis , Estrógenos/toxicidad , Estrona/análisis , Estrona/metabolismo , Estrona/toxicidad , Tracto Gastrointestinal/química , Tracto Gastrointestinal/metabolismo , Luciferasas/genética , Luciferasas/metabolismo , Triclosán/análisis , Triclosán/metabolismo , Triclosán/toxicidad , Contaminantes Químicos del Agua/análisis , Contaminantes Químicos del Agua/toxicidad
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