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Fant 10000 publikasjoner. Viser side 344 av 400:

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Chlorinated paraffins and dechloranes in free-range chicken eggs and soil around waste disposal sites in Tanzania

Haarr, Ane; Nipen, Maja; Mwakalapa, Eliezer Brown; Borgen, Anders; Mmochi, Aviti J.; Borgå, Katrine

Electronic waste is a source of both legacy and emerging flame retardants to the environment, especially in regions where sufficient waste handling systems are lacking. In the present study, we quantified the occurrence of short- and medium chain chlorinated paraffins (SCCPs and MCCPs) and dechloranes in household chicken (Gallus domesticus) eggs and soil collected near waste disposal sites on Zanzibar and the Tanzanian mainland. Sampling locations included an e-waste facility and the active dumpsite of Dar es Salaam, a historical dumpsite in Dar es Salaam, and an informal dumpsite on Zanzibar. We compared concentrations and contaminant profiles between soil and eggs, as free-range chickens ingest a considerable amount of soil during foraging, with potential for maternal transfer to the eggs. We found no correlation between soil and egg concentrations or patterns of dechloranes or CPs. CPs with shorter chain lengths and higher chlorination degree were associated with soil, while longer chain lengths and lower chlorination degree were associated with eggs. MCCPs dominated the CP profile in eggs, with median concentrations ranging from 500 to 900 ng/g lipid weight (lw) among locations. SCCP concentrations in eggs ranged from below the detection limit (LOD) to 370 ng/g lw. Dechlorane Plus was the dominating dechlorane compound in all egg samples, with median concentrations ranging from 0.5 to 2.8 ng/g lw. SCCPs dominated in the soil samples (400–21300 ng/g soil organic matter, SOM), except at the official dumpsite where MCCPs were highest (65000 ng/g SOM). Concentrations of dechloranes in soil ranged from below LOD to 240 ng/g SOM, and the dominating compounds were Dechlorane Plus and Dechlorane 603. Risk assessment of CP levels gave margins of exposure (MOE) close to or below 1000 for SCCPs at one location.

2023

Chiral Xenobiotics in the Environment.

Kallenborn, R.; Hühnerfuss, H.

2001

Chiral MVOC's - a new tool for studying moulds in building constructions? Powerpoint presentation. NILU F

Braathen, O.-A.; Lunder, C.; Schmidbauer, N.; Mattsson, J.; Ahlén, C.

2002

Chiral environmental contaminants in eggs of Norwegian birds of prey. NILU F

Kallenborn, R.; Herzke, D.; Oehme, M.; Nygård, T.

2000

Children and adults in cities: differences in exposure to particulate matter. NILU PP

Fløisand, I.; Mc Innes, H.; Broday, D.; Lützenkirchen, S.; Holländer, W.; Bartonova, A.

2005

Chemistry in aircraft plumes. Poster presentation.

Kraabøl, A. G.; Konopka, P.; Stordal, F.; Knudsen, S.

1999

Chemistry and thermodynamics of organic aerosols. Report series in aerosol science, vol. 71B

Svendby, T.; Hov, Ø.; Lazaridis, M.

2004

Chemicals of Emerging Concern (CECs) in Coastal Waters: Environmental Impacts and Management Strategies

Kallenborn, Roland; Ali, Aasim M.; Hartz, William Frederik; Zhang, Zifeng; Li, Yifan

2024

Chemicals of emerging concern (CECs) in coastal waters: Environmental impact & Management strategies

Kallenborn, Roland; Ali, Aasim M.; Hartz, William Frederik; Zhang, Zifeng; Li, Yifan

2024

Chemicals of Emerging Arctic Concern (CEACs) as local organic pollutants in the Arctic

Ali, Aasim M.; Kallenborn, Roland; Drotikova, Tatiana; Hartz, William Frederik

2024

Chemical tracers of the origins of Arctic air pollution. Environmental Management Series

Pacyna, J. M.

1991

Chemical speciation of fine airborne particles in Abu Dhabi. NILU OR

Hak, C.; Lopez-Aparicio, S.; Sivertsen, B.

Resultater av den kjemiske bestemmelsen av PM2.5 filterprøver fra åtte steder i Abu Dhabi er diskutert. Dette er den tredje rapporten som omfatter i alt 40 filterprøver. Ettersom et mål for denne prøvetakingstudien var å bruke resultatene for konsekvensutredninger for helse, ble prøver med høy partikkelbelastning og høy grad av sorthet valgt for analyse og sammenlignet med prøver med typiske partikkelbelastninger. Partikler med diameter under 2,5 mikrometer ble analysert for 29 elementer, 5 uorganiske ioner og karbonholdige fraksjoner.
De mest vanlige elementer ble funnet å være jordskorpeelementer, som bidrar i gjennomsnitt 14% til PM2,5 masse. Etter rekonstruksjonen av massen med jordskorpeoksider, ble ca 44% av finpartikkelmassen estimert til å være assosiert med mineralstøv. Konsentrasjonene av de fleste tungmetaller var under grenseverdiene for årlig gjennomsnitt på alle områder. For nikkel ble det funnet at årsgrenseverdien kan overskrides på en trafikkmålestasjon.
Uorganiske ioner (sulfat, nitrat, ammonium, natrium, klorid) forklarer i gjennomsnitt 34% av PM2.5 massen i Abu Dhabi. Bemerkelsesverdig høye sulfatkonsentrasjoner utgjør størstedelen (i gjennomsnitt 26%). Partikkelsulfat i Abu Dhabi har sannsynligvis både naturlige (som følge av den lokale sammensetningen av mineralstøv) og antropogene kilder som ikke kan skilles med anvendt analytiske metoder. Et antropogent bidrag på ca 6% kommer fra de sekundære uorganiske ionene nitrat og ammonium.
Totalt karboninnhold, som består av elementært karbon, organisk karbon og karbonatkarbon bidro i gjennomsnitt 14% til PM2.5 -massen. Om lag 30% av det totale karboninnholdet ble anslått til å være karbonat av sannsynligvis naturlig opprinnelse. Elementært karbon og det meste av organisk karbon forventes å være menneskeskapte.
PM i Abu Dhabi har en sterk signatur av naturlige kilder (mineralstøv). En detaljert fordeling av kilder krever videre analyser.

2011

Chemical speciation of fine airborne particles in Abu Dhabi. NILU OR

Hak, C.; Lopez-Aparicio, S.

PM2.5 was sampled at two urban background sites in Abu Dhabi (Khalifa in the city of Abu Dhabi and Bida Zayed) and analysed chemically for further source identification and quantification. Understanding of source contributions to PM2.5 is a prerequisite for the formulation of effective control strategies for PM2.5 emissions.
For both sites, five source factors were identified. Long-range transported aerosol is the largest contributor (~41%) to average PM2.5 mass concentrations at both sites. It gradually forms from SO2, which is possibly emitted into ambient in the Arabian Gulf area, while it is transported to the sites. Mineral dust was found to be the second most important source, contributing ~25% at both sites. It represents an ubiquitous natural contribution of mainly regional origin to particulate matter in Abu Dhabi.
Other source contributions to particle concentrations found at Khalifa identified were: local traffic (15.1%), shipping/industry (10.5%) and sea salt (4.0%). The latter is a natural contribution.
At Bida Zayed, a mixed traffic/industry factor (13.2%) was found, as well as another two factors of natural origin, explaining 11.4% and 8.7%

2013

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