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... CONTENTS -- Page -- GLOSSARY 18 -- BROMINATED DIPHENYL ETHERS - GENERAL INTRODUCTION 25 -- 1. ... ... GENERAL INFORMATION ON BROMINATED -- DIPHENYL ETHERS 31 -- 2.1 Analytical methods 31 -- ^2.2 Production ... ... ina ted diphenyl ethers -- 6. ... ... PREVIOUS EVALUATIONS BY INTERNATIONAL -- BODIES 130 -- NONABROMODIPHENYL ETHER 131 -- 1. ... ... -- OCTABROMODIPHENYL ETHER 137 -- 1. ...
Environmental health criteria ; 162
[1st ed.] 347 s. : tab., grafy ; 21 cm
- MeSH
- fenylethery škodlivé účinky MeSH
- maximální přípustná koncentrace MeSH
- pracovní expozice MeSH
- vystavení vlivu životního prostředí MeSH
- Konspekt
- Hygiena. Lidské zdraví
- NLK Obory
- pracovní lékařství
- environmentální vědy
- NLK Publikační typ
- publikace WHO
- MeSH
- antidepresiva chemická syntéza toxicita MeSH
- experimenty na zvířatech MeSH
- myši MeSH
- Check Tag
- myši MeSH
Polybrominated diphenyl ethers (PBDE) were, and in some countries still are, used as flame retardants for plastic materials. When released from plastics, PDBE cause harm to the environment. This creates the incentive for further investigation of the PBDE degradation. This work focused on a formulation of a PBDE photodegradation model based on the PBDE properties obtained by the quantum chemical calculations. The proposed model predicted degradation routes of arbitrary PBDE congener. The routes of selected congeners were validated by the two independently published data sets and showed the high fitting degree. The model can be easily modified for any reactor system if the initial reaction rate constant of one congener is available for the given system.
Selectivity of electromembrane extractions (EMEs) was fine-tuned by modifications of supported liquid membrane (SLM) composition using additions of various 18-crown-6 ethers into 1-ethyl-2-nitrobenzene. Gradually increased transfer of K(+) , the cation that perfectly fits the cavity of 18-crown-6 ethers, was observed for EMEs across SLMs modified with increasing concentrations of 18-crown-6 ethers. A SLM containing 1% w/v of dibenzo-18-crown-6 in 1-ethyl-2-nitrobenzene exhibited excellent selectivity for EMEs of K(+) . The established host-guest interactions between crown ether cavities in the SLM and potassium ions in donor solution ensured their almost exhaustive transfer into acceptor solution (extraction recovery ∼92%) within 30 min of EME at 50 V. Other inorganic cations were not transferred across the SLM (Ca(2+) and Mg(2+) ) or were transferred negligibly (NH4 (+) , Na(+) ; extraction recovery < 2%) and had only subtle effect on EMEs of K(+) . The high selectivity of the tailor-made SLM holds a great promise for future applications in EMEs since the range of similar selective modifiers is very broad and may be applied in various fields of analytical chemistry.
Due to widespread accumulation of polybrominated diphenyl ethers (PBDEs) in our surroundings, it is important to clarify their fate in the environment and the options of their elimination. The aim of this study was to monitor the biodegradation of the most frequent congeners (BDE 28, 47, 49, 66, 85, 99, 100, 153, 154, 183 and 209) under aerobic condition by indigenous microflora in 2 industrially contaminated sewage sludge samples. BDE 209 was detected as the predominating congener in concentrations 685 ng/g and 1403 ng/g dry weight in sewage sludge from WWTPs (waste water treatment plants) Hradec Kralove and Brno, respectively. The total amount of 10 lower PBDEs was 605 and 205 ng/g dry weight, respectively. The aerobic degradation was significantly enhanced by the addition of yeast extract and 4-bromobiphenyl. The total concentrations of all 11 PBDE congeners were lowered and their elimination was detected reaching 62–78% of their initial amounts after 11 months of cultivation. The degradation of most abundant congener BDE 209 followed the first-order kinetics with constant detected between 2.77 × 10(−3) d(−1) and 3.79 × 10−(3)d(−1) and the half-lives of BDE 209 degradation ranged between 6.0 and 8.2 months. This work clearly demonstrates that both lower brominated PBDEs as well as the major representative BDE 209 could be successfully removed from municipally contaminated sludge under aerobic conditions.
- MeSH
- aerobióza MeSH
- biodegradace MeSH
- chemické látky znečišťující vodu analýza MeSH
- čištění vody metody MeSH
- halogenované difenylethery analýza MeSH
- monitorování životního prostředí MeSH
- odpadní voda analýza chemie mikrobiologie MeSH
- odpadní vody analýza chemie mikrobiologie MeSH
- polybrombifenylové sloučeniny analýza MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Geografické názvy
- Česká republika MeSH
Plastic waste of electrical and electronic equipment (WEEE) can contain polybrominated diphenyl ethers (PBDEs) that have been used as fire retardants for a long time. PBDEs were listed in the Stockholm Convention as persistent organic pollutants, so PBDE-containing plastic waste should be separated and disposed of in an ecologically sound manner. In the article, the results of bromine and PBDE content in plastic samples of WEEE collected in Belarus are presented. The screening method for bromine identification and HRGC/HRMS for PBDE identification were applied. It is shown that bromine is present in 43% of the 111 studied samples. Most often, Br-containing plastic was found in CRT monitor, CRT TVs and LCD monitor (about 50%), printers (35%), and LCD TVs (25%). PBDEs were revealed in 12 Br-containing samples, representing TVs, monitors, and printers. The sum of ∑10PBDEs varied from 6.6 to 21,000 μg/kg. BDE-209 dominated in 9 samples (75% of cases); BDE-183, in two; and BDE-47 and BDE-99, in one sample. Based on the low content of PBDEs in the plastic, year of equipment production, and year of restriction of PBDEs applied in the countries-manufacturers, it was concluded that the presence of PBDEs in plastic is a consequence of contaminated waste recycling. Despite the relatively low concentrations of PBDEs (below the limit values established by the Stockholm and Basel conventions for POP wastes), further research is necessary with an extension of the list of analyzed types of equipment and identification of other brominated flame retardants.
- MeSH
- elektronický odpad analýza MeSH
- halogenované difenylethery analýza MeSH
- monitorování životního prostředí MeSH
- plastické hmoty MeSH
- retardanty hoření analýza MeSH
- Publikační typ
- časopisecké články MeSH
- Geografické názvy
- Běloruská republika MeSH
Polybrominated diphenyl ethers (PBDEs) are used as additive flame retardants. PBDEs are persistent, bioaccumulative and toxic compounds. They are often detected in sewage sludge which is applied on agricultural soils as fertilizer. The objective of this study was to find out whether plants are able to accumulate and translocate PBDEs. Tobacco (Nicotiana tabacum) and nightshade (Solanum nigrum) were planted in pots containing contaminated sewage sludge and uncontaminated substrate. After 6 months of plant cultivation in sewage sludge up to 15.4 ng g(-1) dw and 76.6 ng g(-1) dw of PBDE congeners--BDE 47, BDE 99 and BDE 100---were accumulated in the nightshade and tobacco tissue, respectively. Corresponding values in plants vegetated in the control garden substrate were 10 times lower. The bioconcentration factors (BCFs) of accumulated congeners were calculated. Tobacco exhibited higher BCFs values and for both plants BCFs values of BDE 47, BDE 99, BDE 100 and BDE 209 negatively correlated with their octanol-water partition coefficients (logK(ow)). The exception was decaBDE (BDE 209) which was accumulated only in tobacco tissue in the concentration of 116.8 ng g(-1) dw. The majority of PBDEs was detected in above-ground plant biomass indicating that both plants have the ability to translocate PBDEs. To our knowledge this is one of the first studies reporting the accumulation of both lower PBDEs and BDE 209 in plants. Our results suggest that absorption, accumulation and translocation of PBDEs by plants and their transfer to the food chain could represent another possible risk for human exposure.
- MeSH
- biodegradace MeSH
- halogenované difenylethery analýza metabolismus MeSH
- látky znečišťující půdu analýza metabolismus MeSH
- odpadní vody chemie MeSH
- retardanty hoření analýza metabolismus MeSH
- rostliny metabolismus MeSH
- Solanum růst a vývoj metabolismus MeSH
- tabák růst a vývoj metabolismus MeSH
- vývoj rostlin MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
