RESUMO
This study report the presence of polybrominated biphenyls (PBBs), polybrominated diphenyl ethers (PBDEs) and novel brominated flame-retardants (NBFRs) in muscle tissues of Labeo capensis (mudfish), Labeo umbratus (moggel), Cyprinus carpio (carp) and Clarias gariepinus (catfish) from Vaal River, South Africa. The concentrations (in ng g-1 wet weight (ww)) of these contaminants ranged from LOQ to 12.8 ng g-1 ww in catfish, with lowest concentrations found for mudfish ranging from Assuntos
Carpas
, Retardadores de Chama
, Animais
, Monitoramento Ambiental
, Retardadores de Chama/análise
, Humanos
, Rios
, África do Sul
RESUMO
It has been extensively demonstrated that plants accumulate organic substances emanating from various sources, including soil and water. This fact suggests the potentiality of contamination of certain vital bioresources, such as medicinal plants, by persistent contaminants, such as perfluorooctanoic acid (PFOA), perfluorooctane sulfonate (PFOS), and perfluorobutane sulfonate (PFBS). Hence, in this study, the propensity of Tagetes erecta L. (a commonly used medicinal plant) to accumulate PFOA, PFOS, and PFBS was determined using liquid chromatography/tandem mass spectrometry (LCâ»MS/MS-8030). From the results, PFOA, PFOS, and PFBS were detected in all the plant samples and concentration levels were found to be 94.83 ng/g, 5.03 ng/g, and 1.44 ng/g, respectively, with bioconcentration factor (BCF) ranges of 1.30 to 2.57, 13.67 to 72.33, and 0.16 to 0.31, respectively. Little evidence exists on the bioaccumulative susceptibility of medicinal plants to these persistent organic pollutants (POPs). These results suggest that these medicinal plants (in particular, Tagetes erecta L., used for the management of diabetes) are also potential conduits of PFOA, PFOS, and PFBS into humans.
RESUMO
The presence of phthalate esters (PAEs) in the environment is not desirable and therefore, needs to be monitored. This study reports the first data on the concentration levels of PAEs in water and sediments of the Jukskei River catchment area, South Africa. The study was conducted during the summer and winter seasons of 2005. Liquid-liquid extraction (LLE) and Soxhlet extraction (SE) methods were optimized, evaluated and used to determine PAEs of interest in water (unfiltered and filtered) and sediments samples, respectively. Mean percentage recoveries in spiked doubly distilled water ranged from 100 ± 5.32 dimethyl phthalate (DMP) - 122 ± 0.46 di-2-ethylhexyl phthalate (DEHP) and 91.6 ± 1.93 diethyl phthalate (DEP) - 117 ± 4.80 dibutyl phthalate (DBP) in sediments. The concentration levels of PAEs studied in unfiltered environmental water samples were in the range of 0.04(± 0.00) (DMP) - 9.76(± 00.1) ng mL(-1)(DEHP) for PAEs and from 0.09 (± 0.01) (DMP) - 4.38 (± 0.06) ng mL(-1)(DEHP) for filtered environmental water samples. Concentration levels obtained in sediments were from 0.05 (0.00) (DMP) - 4910 (0.36) ng/gdw (DEHP). PAEs adsorbed on the sample bottle gave concentration levels of up to 0.10 (± 0.03) ng mL(-1)for some samples and no analyte was detected (ND) in some cases Generally, concentrations obtained were below the water quality guideline values of United States Environmental Protection Agency (USEPA).
Assuntos
Sedimentos Geológicos/análise , Ácidos Ftálicos/análise , Dibutilftalato/análise , Extração Líquido-Líquido , África do Sul , Poluentes Químicos da Água/análiseRESUMO
A gas chromatography-mass spectrometry (GC-MS) method was investigated for the simultaneous analysis of two types of endocrine disrupting compounds (EDCs), i.e., alkylphenol ethoxylates and brominated flame retardants (BFRs), by extraction and derivatization followed by GC-MS. Different solid phase extraction (SPE) cartridges (Cleanert PestiCarb, C18, Cleanert-SAX and Florosil), solvents (toluene, tetrahydrofuran, acetone, acetonitrile and ethyl acetate) and bases (NaHCO3, triethylamine and pyridine) were tested and the best chromatographic analysis was achieved by extraction with Strata-X (33 µm, Reverse Phase) cartridge and derivatization with heptafluorobutyric anhydride at 55 °C under Na2CO3 base in hexane. It was observed that APE together with lower substituted PBBs (PBB1, PBB10, PBB18 and PBB49), HBCD and TBBPA can be determined simultaneously under the same GC conditions. This simple and reliable analytical method was applied to determining trace amounts of these compounds from wastewater treatment plant samples. The recoveries of the target compounds from simulated water were above 60 %. The limit of detection ranged from 0.01 to 0.15 µg L-1 and the limit of quantification ranged from 0.05 to 0.66 µg L-1. There were no appreciable differences between filtered and unfiltered wastewater samples from Leeuwkil treatment plant although concentration of target analytes in filtered influent was slightly lower than the concentration of target analytes in unfiltered influent water. The concentrations of the target compounds from the wastewater treatment were determined from LOQ upwards.
RESUMO
Surface water and sediment samples collected from Jukskei River in South Africa, were subjected to different extraction techniques, liquid-liquid (LLE), solid-phase extraction (SPE), activated carbon extraction (ACE) and soxhlet extraction (SE) for sediment. The samples were extracted with dichloromethane, cleaned in a silica gel column and the extracts quantified using a Varian 3800 GC-ECD. The percentage recovery test for 2,4'DDT, DDE and DDD and 4,4'DDT, DDE and DDD in water ranged from 80%-96% and 76%-95% (LLE); 56%-76% and 56%-70% (SPE) and 75%-84% (ACE), respectively; while that recoveries for sediment samples varied from 65%-95% for 2,4'DDT, DDE and DDD and 80%-91% for 4,4'DDT, DDE and DDD. The high recoveries exhibited by ACE compared very well with LLE and SE. This was not the case with SPE which exhibited the lowest value of recoveries for both 2,4 and 4,4'DDD, DDE and DDT standard samples. The mean concentrations of DDT and metabolites ranged from nd-1.10 µg/L, nd-0.80 µg/L, nd-1.21 µg/L and 1.92 µg/L for LLE, SPE, ACE and SE, respectively. The total DDT (2,4' and 4,4'-DDT) in water and sediment samples ranged from 1.20-3.25 µg/L and 1.82-5.24 µg/L, respectively. The low concentrations of the DDT metabolites obtained in the present study may suggest a recent contamination of the river by DDT.