Effects of plant species identity, diversity and soil fertility on biodegradation of phenanthrene in soil
Oyelami, A.O. ; Okere, U.V. ; Orwin, K. ; Deyn, G.B. de; Jones, K.C. ; Semple, K.T. - \ 2013
Environmental Pollution 173 (2013). - ISSN 0269-7491 - p. 231 - 237.
polycyclic aromatic-hydrocarbons - volatile organic-compounds - microbial communities - grassland communities - contact time - rhizosphere - bioavailability - mineralization - pahs - microorganisms
The work presented in this paper investigated the effects of plant species composition, species diversity and soil fertility on biodegradation of 14C-phenanthrene in soil. The two soils used were of contrasting fertility, taken from long term unfertilised and fertilised grassland, showing differences in total nitrogen content (%N). Plant communities consisted of six different plant species: two grasses, two forbs, and two legume species, and ranged in species richness from 1 to 6. The degradation of 14C-phenanthrene was evaluated by measuring indigenous catabolic activity following the addition of the contaminant to soil using respirometry. Soil fertility was a driving factor in all aspects of 14C-phenanthrene degradation; lag phase, maximum rates and total extents of 14C-phenanthrene mineralisation were higher in improved soils compared to unimproved soils. Plant identity had a significant effect on the lag phase and extents of mineralisation. Soil fertility was the major influence also on abundance of microbial communities.
Impact of polychlorinated biphenyl and polycyclic aromatic hydrocarbon sequestration in sediment on bioaccumulation in aquatic food webs
Moermond, C.T.A. ; Roessink, I. ; Jonker, M.T.O. ; Meijer, T. ; Koelmans, A.A. - \ 2007
Environmental Toxicology and Chemistry 26 (2007)4. - ISSN 0730-7268 - p. 607 - 615.
hydrophobic organic-chemicals - black carbon - benthic organisms - contact time - bioavailability - desorption - sorption - lake - accumulation - extraction
It is not clear whether sequestration or aging of organic chemicals like polychlorinated biphenyls (PCBs) and polycyclic aromatic hydrocarbons (PAHs) limits accumulation in higher levels of aquatic food chains. Therefore, the effect of aging on accumulation was studied in 1-m3 model ecosystems that mimicked fish-dominated, macrophyte-dominated, and fish- and macrophyte-dominated shallow lakes. Also treatments without fish and macrophytes were included. General characteristics, biomasses, total (Soxhlet-extractable), and labile (6-h Tenax-extractable) PCB and PAH concentrations in sediment and biota were monitored over time. Accumulation data for PCB 28, PCB 149, and fluoranthene (native to the sediment taken from the field) were compared to those for spiked analogues PCB 29, PCB 155, and fluoranthene-d10. Labile fractions for spiked compounds were higher than for their native analogues and decreased over time, suggesting sequestration in the sediment. In the majority of cases, 6-h Tenax-extractable concentrations correlated better with concentrations in biota than Soxhlet-extractable concentrations. Ecosystem structure affected food web accumulation, but replicate variability was too high to detect clear treatment effects. Differences in accumulation between spiked compounds and their native analogues indicated an effect of aging for invertebrates, macrophytes, and benthivorous fish. Thus, aging may translate directly into reduced uptake at higher trophic levels.
Extremely slowly desorbing polycyclic aromatic hydrocarbons from soot and soot-like materials: Evidence by supercritical fluid extraction
Jonker, M.T.O. ; Hawthorne, S.B. ; Koelmans, A.A. - \ 2005
Environmental Science and Technology 39 (2005)20. - ISSN 0013-936X - p. 7889 - 7895.
hydrophobic organic-chemicals - carbon-dioxide extraction - polychlorinated-biphenyls - black carbon - desorption-kinetics - sorption mechanism - sorbate planarity - water desorption - contact time - pah release
Combustion-derived PAHs are strongly sorbed to their particulate carrier (i.e., soot, charcoal), and therefore, very slow desorption kinetics of the chemicals might be anticipated. Measurements are however lacking, because conventional methods (Tenax, XAD, gas-purging) fail to accurately determine desorption kinetics due to practical problems. In this study, we used a mild supercritical fluid extraction (SFE) method, which mimics desorption into water and circumvents these problems, to quantify desorption kinetics of 13 native PAHs from pure charcoal, coal, and four types of soot. The results show that generally only very small PAH fractions are released. Desorption behavior was, however, not related to common sorbent/sorbate characteristics. Two-site model-derived "fast desorbing fractions" were
Uptake of sediment-bound bioavailable polychlorobiphenyls by benthivorous carp (Cyprinus carpio)
Moermond, C.T.A. ; Roozen, F.C.J.M. ; Zwolsman, J.J.G. ; Koelmans, A.A. - \ 2004
Environmental Science and Technology 38 (2004)17. - ISSN 0013-936X - p. 4503 - 4509.
sediment - biologische beschikbaarheid - polychloorbifenylen - benthos - karper - zoetwatervissen - meren - waterinvertebraten - chemicaliën - opname (uptake) - organische scheikunde - ecotoxicologie - waterbodems - sediment - bioavailability - polychlorinated biphenyls - benthos - carp - freshwater fishes - lakes - aquatic invertebrates - chemicals - uptake - organic chemistry - ecotoxicology - water bottoms - hydrophobic organic contaminants - aquatic food webs - contact time - pore-water - ingested sediment - extraction - lake - pollutants - fish
It is unclear whether accumulation of sediment-bound chemicals in benthivorous fish depends on the degree of sequestration in the sediment like it does for invertebrates. Here, we report on the potential of slow and fast desorbing sediment-bound polychlorobiphenyl (PCB) fractions for accumulation in carp (Cyprinus carpio) in lake enclosures treated with different nutrient doses
It is unclear whether accumulation of sediment-bound chemicals in benthivorous fish depends on the degree of sequestration in the sediment like it does for invertebrates. Here, we report on the potential of slow and fast desorbing sediment-bound polychlorobiphenyl (PCB) fractions for accumulation in carp (Cyprinus carpio) in lake enclosures treated with different nutrient doses. Routes of PCB uptake were quantitatively evaluated for 15 PCBs (log K-0W range 5.6-7.8) using model analysis. Fast-desorbing PCB fractions in the sediment were defined as the ratio of 6-h Tenax-extractable to (total) Soxhlet-extractable concentrations. These fractions varied between 4 and 22% and did not show a clear trend with log K-0W. However, bioaccumulation of PCBs in carp correlated much better with Tenax-extractable concentrations than with total-extractable concentrations. Nutrient additions in the enclosures had a positive effect on PCB accumulation. Model results show that PCB uptake in carp can be explained from (1) uptake through invertebrate food, (2) uptake from fast-desorbing fractions in ingested sediments, and (3) uptake from water, where PCBs are in partitioning equilibrium with fast-desorbing fractions. The main implication of this research is that fast-desorbing PCB fractions in sediments have great predictive potential for bioaccumulation in benthivorous fish.