| 1. |
- Ejlertsson, Jörgen, et al.
(författare)
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Anaerobic Degradation of Nonylphenol Mono- and Diethoxylates in Digestor Sludge, Landfilled Municipal Solid Waste, and Landfilled Sludge
- 1999
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Ingår i: Environmental Science and Technology. - : American Chemical Society (ACS). - 1086-931X .- 1520-6912 .- 0013-936X .- 1520-5851. ; 33:2, s. 301-306
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Tidskriftsartikel (refereegranskat)abstract
- The aim of this study was to investigate the extent to which anaerobic digestor sludge, landfilled sludge, and landfilled municipal solid waste (MSW) degrade NPEOs under methanogenic conditions. NPEO1 and NPEO2 (NPEO1-2), used in a mixture, were chosen as model compounds. Anaerobic experimental bottles were amended with 100% digestor sludge at three different concentrations of NPEO1-2: 2, 60, and 308 mg L-1. [U-14C]-NPEO1-2 was used to detect any possible decomposition of the aromatic moiety of the NPEO1-2. All inoculates used degraded NPEO1-2 at 2 mg L-1, with nonylphenol (NP) forming the ultimate degradation product. The NP formed was not further degraded, and the incubations with labeled NPEO showed that the aromatic structure remained intact. Both landfill inoculates also transformed NPEO1-2 at 60 mg L-1. CH4 production was temporarily hampered in bottles with MSW landfill inoculum at 60 and 308 mg L-1. With 2 mg L-1 of NPEO, CH4 production closely followed that in the controls. Both NP and NPEO1-2 interacted with the organic matter which resulted in sorption to the solid phase.
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| 3. |
- Sjödin, Andreas, et al.
(författare)
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Flame retardant exposure: polybrominated diphenyl ethers in blood from Swedish workers.
- 1999
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Ingår i: Environmental Health Perspectives. - 1552-9924. ; 107:8, s. 643-648
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Tidskriftsartikel (refereegranskat)abstract
- Polybrominated diphenyl ethers (PBDEs) are used as additives in polymers and textiles to prohibit the development of fires. Because of the production and use of PBDEs, their lipophilic characteristics, and persistence, these compounds have become ubiquitous environmental contaminants. The aim of the present study was to determine potential exposures of PBDEs to clerks working full-time at computer screens and personnel at an electronics-dismantling plant, with hospital cleaners as a control group. Five PBDE congeners--2,2´,4,4´-tetraBDE ; 2,2´,4,4´,5,5´-hexaBDE ; 2,2´,4,4´,5,6´-hexaBDE ; 2,2´,3,4,4´,5´,6-heptaBDE ; and decaBDE--were quantified in blood serum from all three categories of workers. Subjects working at the dismantling plant showed significantly higher levels of all PBDE congeners in their serum as compared to the control group. Decabromodiphenyl ether is present in concentrations of 5 pmol/g lipid weight (lw) in the personnel dismantling electronics ; these concentrations are comparable to the concentrations of 2,2´,4,4´-tetraBDE. The latter compound was the dominating PBDE congener in the clerks and cleaners. The major compound in personnel at the dismantling plant was 2,2´,3,4,4´,5´,6-heptaBDE. Concentrations of this PBDE congener are almost twice as high as for 2,2´,4,4´-tetraBDE in these workers and seventy times the level of this heptaBDE in cleaners. The total median PBDE concentrations in the serum from workers at the electronics-dismantling plant, clerks, and cleaners were 37, 7.3, and 5.4 pmol/g lw, respectively. The results show that decabromodiphenyl ether is bioavailable and that occupational exposure to PBDEs occurs at the electronics-dismantling plant.
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