Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 3 de 3
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
Bull Environ Contam Toxicol ; 97(3): 353-8, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27443342

RESUMO

High environmental concentrations for alkylphenol ethoxylates (APEs) and brominated flame retardants (BFRs) have been observed near cities than in rural environment. This is due, in part, to sewage systems receiving effluents from many industrial processes along with domestic wastewater. While these classes of compounds are being phased out in most developed countries, there is still widespread use in low to middle income countries. To better understand the extent of APEs and BFRs contamination in the environment, this study reports on the concentration and distribution of APEs and BFRs in sediments samples collected from Vaal River, South Africa. Measurable concentrations of these contaminants were obtained using GC-MS after heptafluorobutyric derivatization. The concentrations range (ng g(-1)) for these pollutants were as follows: nd-46, 20-127, 24-38, 3-5, 14-28, 16-54 for octylphenol penta ethoxylates, nonylphenol ethoxylates (mono- di), nonylphenol penta ethoxylates, PBB101, PBDEs, and HBCD; respectively. The distribution observed in this study indicated higher levels of sediment contamination by APEs relative to BFRs. These results underline the need to further investigate the burden and risks associated with chemical contamination in developing countries.


Assuntos
Monitoramento Ambiental , Retardadores de Chama/análise , Rios/química , Poluentes Químicos da Água/análise , Cromatografia Gasosa-Espectrometria de Massas , Éteres Difenil Halogenados/análise , Fenóis/análise , Esgotos , África do Sul , Águas Residuárias/química
2.
Environ Sci Pollut Res Int ; 22(15): 11922-9, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25869432

RESUMO

Alkylphenol ethoxylates (APEs) and brominated flame retardants (BFRs) are known to be bio-accumulative, persistent, and endocrine disruptors and can cause adverse health effects in animals and humans. In this study, environmental samples were collected from sites along the Vaal River, South Africa in order to determine the concentrations of APEs and BFRs in water, sediment, and fish samples. The highest concentrations of these pollutants were observed from discharge of the Rietspruit WWTW. Measurable levels of both APEs and BFRs were observed with APEs exhibiting higher concentrations than BFRs in all the matrices. The concentrations observed for APEs and BFRs were as follows: 1.00-3.85 µg/L APEs, 0.09-0.26 µg/L PBDEs, ND- 0.14 PBBs and 0.51-1.77 µg/L HBCD for water samples; 47-63 ng/g lipid APEs, 3.24-12.4 ng/g lipid PBB, 4.63-33 ng/g lipid PBDEs and 10-13 ng/g lipid HBCD for fish; and 40-184 ng/g (wet weight (ww)) APEs, 2.93-5.9 ng/g (ww) PBB, 10-24 ng/g (ww) PBDEs, and 15-52 ng/g (ww) HBCD for sediment samples. The concentrations of APEs and BFRs in water samples were found to be in the range with the results reported in the literature while the concentration in fish and sediment were lower than the concentrations reported in other studies.


Assuntos
Retardadores de Chama/análise , Fenóis/análise , Bifenil Polibromatos/análise , Poluentes Químicos da Água/análise , Animais , Carpas , Sedimentos Geológicos/química , Rios/química , África do Sul
3.
Water Sci Technol ; 69(12): 2389-96, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24959999

RESUMO

An improved derivatization protocol for the simultaneous determination of alkylphenol ethoxylates and brominated flame retardants with heptafluorobutyric anhydride under triethylamine amine base was investigated. The derivatization reaction was completed in 30 min at 50 °C using hexane as solvent. Under these conditions, it was observed that alkylphenol ethoxylates and tetrabromobisphenol A were derivatized successfully in the presence of hexabromocyclododecane, lower congeners of polybrominated biphenyls and polybrominated diphenyl ethers. The improved protocol was applied to the recover of the analytes of interest from a simulated water sample after solid phase extraction. The recoveries achieved were above 60%. The limit of detection and limit of quantification ranged from 0.01-0.20 and 0.05-0.66 µg L(-1), respectively. The improved derivatization procedure was also successfully applied to determine trace amounts of these compounds in environmental water samples. The concentrations of the targeted analytes from the environmental samples were determined from limit of quantification. The levels of the targeted compounds in the environmental samples ranged from nd-7.63 ±2.83 µg L(-1).


Assuntos
Retardadores de Chama/análise , Cromatografia Gasosa-Espectrometria de Massas/métodos , Poluentes Químicos da Água/química , Monitoramento Ambiental , Modelos Teóricos , África do Sul
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...