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Persistent organic pollutants (PCB, DDT, HCH, HCB & BDE) in eels (Anguilla anguilla) in Scotland: Current levels and temporal trends
2010
Macgregor, Kenneth | Oliver, Ian W. | Harris, Lynsay | Ridgway, Ian M.
Eels are an ideal biomonitor for persistent organic pollutants (POPs) because of their high lipid content, longevity and tendency to remain within a defined range during their freshwater life phase. This study investigated concentrations of POPs in eels (Anguilla anguilla) from 30 sites across Scotland, including polychlorinated biphenyls (PCBs), polybrominated diphenyl ethers (BDEs), DDT (and metabolites), hexachlorocyclohexanes (α, β, γ-HCH), hexachlorobenzene (HCB), hexachlorobutadiene (HCBD) and pentachlorobenzene. Despite its EU-wide ban ∼30 years ago, DDT and its derivatives were detected in almost all samples. PCB 153 and 138 were the most widely detected PCB congeners, while BDE 47 was the dominant BDE. Pentachlorobenzene was not detected, while HCBD was detected once only. α-HCH, β-HCH and HCB concentrations were very low (generally <3 μg/kg or below detection). When compared with 1986 and 1995 data, the results revealed considerable decreases in p,p′-DDE concentrations. More drastic reductions were evident for γ-HCH, reflecting the tightening restrictions on pesticide use imposed over the previous decades.
Show more [+] Less [-]Nitrogen mediates above-ground effects of ozone but not below-ground effects in a rhizomatous sedge
2010
Jones, M.L.M. | Hodges, G. | Mills, G.
Ozone and atmospheric nitrogen are co-occurring pollutants with adverse effects on natural grassland vegetation. Plants of the rhizomatous sedge Carex arenaria were exposed to four ozone regimes representing increasing background concentrations (background-peak): 10–30, 35–55, 60–80 and 85–105 ppb ozone at two nitrogen levels: 12 and 100 kg N ha−1 yr−1. Ozone increased the number and proportion of senesced leaves, but not overall leaf number. There was a clear nitrogen × ozone interaction with high nitrogen reducing proportional senescence in each treatment and increasing the ozone dose (AOT40) at which enhanced senescence occurred. Ozone reduced total biomass due to significant effects on root biomass. There were no interactive effects on shoot:root ratio. Rhizome tissue N content was increased by both nitrogen and ozone. Results suggest that nitrogen mediates above-ground impacts of ozone but not impacts on below-ground resource translocation. This may lead to complex interactive effects between the two pollutants on natural vegetation. Nitrogen alters threshold of ozone-induced senescence, but not below-ground resource allocation.
Show more [+] Less [-]Agricultural ammonia emissions inventory and spatial distribution in the North China Plain
2010
Zhang, Y. | Dore, A.J. | Ma, L. | Liu, X.J. | Ma, W.Q. | Cape, J.N. | Zhang, F.S.
An agricultural ammonia (NH3) emission inventory in the North China Plain (NCP) on a prefecture level for the year 2004, and a 5 × 5 km2 resolution spatial distribution map, has been calculated for the first time. The census database from China's statistics datasets, and emission factors re-calculated by the RAINS model supported total emissions of 3071 kt NH3–N yr−1 for the NCP, accounting for 27% of the total emissions in China. NH3 emission from mineral fertilizer application contributed 1620 kt NH3–N yr−1, 54% of the total emission, while livestock emissions accounted for the remaining 46% of the total emissions, including 7%, 27%, 7% and 5% from cattle, pigs, sheep and goats, and poultry, respectively. A high-resolution spatial NH3 emissions map was developed based on 1 × 1 km land use database and aggregated to a 5 × 5 km grid resolution. The highest emission density value was 198 kg N ha−1 yr−1. The first high-resolution spatial distribution of ammonia emissions for the North China Plain showed rates up to 200 kg NH3–N ha−1 yr−1.
Show more [+] Less [-]Effects of amendments on the uptake and distribution of DDT in Cucurbita pepo ssp pepo plants
2010
Åslund, Melissa L Whitfield | Lunney, Alissa I. | Rutter, Allison | Zeeb, Barbara A.
The effects of soil amendments on the phytoextraction of ∑DDT (DDT + DDD + DDE) from soil ([∑DDT] not, vert, similar 1500 ng/g) by a pumpkin variety of Cucurbita pepo ssp pepo were tested and the patterns of ∑DDT storage throughout the plant shoot were examined. The soil amendments did not increase the total amount of ∑DDT extracted into plant shoots, but new information about ∑DDT distribution in the plants was obtained. As observed previously, the ∑DDT concentration in plant leaves (mean 290 ng/g) was significantly lower than in plant stems (mean 2600 ng/g). Further analysis revealed that ∑DDT composition was consistent throughout the plant shoot and that ∑DDT concentration in leaves and stems decreased exponentially as distance from the root increased, which was previously unknown. This new information about the patterns of ∑DDT uptake and translocation within pumpkin plants highlights the need for appropriate plant sampling strategies in future POPs phytoextraction research. Patterns of ∑DDT storage in a pumpkin plant are elucidated and specific surfactant and mycorrhizal soil amendments did not increase the total amount of ∑DDT phytoextracted into plant shoots.
Show more [+] Less [-]Copper mobilization affected by weather conditions in a stormwater detention system receiving runoff waters from vineyard soils (Champagne, France)
2010
Banas, D. | Marin, B. | Skraber, S. | Chopin, E.I.B. | Zanella, A.
Copper, a priority substance on the EU-Water Framework Directive list, is widely used to protect grapevines against fungus diseases. Many vineyards being located on steep slopes, large amounts of Cu could be discharged in downstream systems by runoff water. The efficiency of stormwater detention basins to retain copper in a vineyard catchment was estimated. Suspended solids, dissolved (Cudiss) and total Cu (Cutot) concentrations were monitored in runoff water, upstream, into and downstream from a detention pond. Mean Cutot concentrations in entering water was 53.6 μg/L whereas it never exceeded 2.4 μg/L in seepage. Cutot concentrations in basin water (>100 μg/L in 24% of the samples) exceeded LC50 values for several aquatic animals. Copper was principally sequestered by reduced compounds in the basin sediments (2/3 of Cutot). Metal sequestration was reversible since sediment resuspension resulted in Cu remobilization. Wind velocity controlled resuspension, explained 70% of Cudiss variability and could help predicting Cu mobilization. Copper in stormwater basin is efficiently retained but can be released during windy events or after dredging.
Show more [+] Less [-]Distribution of polybrominated diphenyl ethers (PBDEs) and polybrominated dibenzo-p-dioxins and dibenzofurans (PBDD/Fs) in municipal solid waste incinerators
2010
Wang, Lin-Chi | Hsi, Hsing-Cheng | Wang, Yafen | Lin, Sheng-Lun | Chang-Chien, Guo-Ping
The stack flue gases and the ashes in different units of two municipal solid waste incinerators (MSWIs) are sampled to investigate the characteristics of polybrominated diphenyl ethers (PBDEs), polybrominated dibenzo-p-dioxins and dibenzofurans (PBDD/Fs), and polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs). Bottom ashes (BA) exhibited much higher PBDD/F (8.11-52.2 pg TEQ/g) and PBDE contents (20.4-186 ng/g) than those of fly ashes (0.0932-2.02 pg TEQ/g and 0.332–25.5 ng/g), revealing that the PBDD/Fs and PBDEs in the feeding waste may not be completely destroyed. The PBDE concentrations/contents in the stack flue gases (26.1-109 ng/Nm3) and in the BA (20.4-186 ng/g) of the MSWIs could reach three orders higher than those in the atmosphere and reference soils. PBDE contributions to the environment from the stack flue gases or the reutilization of BA of MSWIs should not be ignored from the developing PBDE inventory.
Show more [+] Less [-]Hydroxypropyl-β-cyclodextrin as non-exhaustive extractant for organochlorine pesticides and polychlorinated biphenyls in muck soil
2010
Wong, Fiona | Bidleman, Terry F.
Hydroxypropyl-β-cyclodextrin (HPCD) was used as a non-exhaustive extractant for organochlorine pesticides (OCs) and polychlorinated biphenyls (PCBs) in muck soil. An optimized extraction method was developed which involved using a HPCD to soil mass ratio of 5.8 with a single extraction period of 20 h. An aging experiment was performed by spiking a muck soil with 13C-labeled OCs and non-labeled PCBs. The soil was extracted with the optimized HPCD method and Soxhlet apparatus with dichloromethane over 550 d periodically. The HPCD extractability of the spiked OCs was greater than of the native OCs. A decreased in HPCD extractability was observed for the spiked OCs after 550 d of aging and their extractability approached those of the natives. The partition coefficient between HPCD and soil (log KCD-Soil) was negatively correlated with the octanol-water partition coefficient (log KOW) with r2 = 0.67 and p < 0.05.
Show more [+] Less [-]Elevated carbon dioxide does not offset loss of soil carbon from a corn-soybean agroecosystem
2010
Moran, Kelly K. | Jastrow, Julie D.
The potential for storing additional C in U.S. Corn Belt soils – to offset rising atmospheric [CO2] – is large. Long-term cultivation has depleted substantial soil organic matter (SOM) stocks that once existed in the region's native ecosystems. In central Illinois, free-air CO2 enrichment technology was used to investigate the effects of elevated [CO2] on SOM pools in a conservation tilled corn–soybean rotation. After 5 and 6 y of CO2 enrichment, we investigated the distribution of C and N among soil fractions with varying ability to protect SOM from rapid decomposition. None of the isolated C or N pools, or bulk-soil C or N, was affected by CO2 treatment. However, the site has lost soil C and N, largely from unprotected pools, regardless of CO2 treatment since the experiment began. These findings suggest management practices have affected soil C and N stocks and dynamics more than the increased inputs from CO2-stimulated photosynthesis. Soil carbon from microaggregate-protected and unprotected fractions decreased in a conservation tilled corn–soybean rotation despite increases in primary production from exposure to atmospheric CO2 enrichment.
Show more [+] Less [-]Fresh organic matter of municipal solid waste enhances phytoextraction of heavy metals from contaminated soil
2010
Salati, S. | Quadri, G. | Tambone, F. | Adani, F.
In this study, the ability of the organic fraction of municipal solid wastes (OFMSW) to enhance heavy metal uptake of maize shoots compared with ethylenediamine disuccinic acid (EDDS) was tested on soil contaminated with heavy metals. Soils treated with OFMSW and EDDS significantly increased the concentration of heavy metals in maize shoots (increments of 302%, 66%, 184%, 169%, and 23% for Cr, Cu, Ni, Zn, and Pb with respect to the control and increments of 933%, 482%, 928%, 428%, and 5551% for soils treated with OFMSW and EDDS, respectively). In soil treated with OFMSW, metal uptake was favored because of the high presence of dissolved organic matter (DOM) (41.6× than soil control) that exhibited ligand properties because of the high presence of carboxylic acids. Because of the toxic effect of EDDS on maize plants, soil treated with OFMSW achieved the highest extraction of total heavy metals.
Show more [+] Less [-]Estimating contribution of wildland fires to ambient ozone levels in National Parks in the Sierra Nevada, California
2010
Preisler, Haiganoush K. | Chung, S. Y (Sze Yuen) | Esperanza, Annie | Brown, Timothy J. | Bytnerowicz, Andrzej | Tarnay, Leland
monitoring sites operated by the National Park Service in Sierra Nevada, California, are used to develop an ozone forecasting model and to estimate the contribution of wildland fires on ambient ozone levels. The analyses of weather and ozone data pointed to the transport of ozone precursors from the Central Valley as an important source of pollution in these National Parks. Comparisons of forecasted and observed values demonstrated that accurate forecasts of next-day hourly ozone levels may be achieved by using a time series model with historic averages, expected local weather and modeled PM values as explanatory variables. Results on fire smoke influence indicated occurrence of significant increases in average ozone levels with increasing fire activity. The overall effect on diurnal ozone values, however, was small when compared with the amount of variability attributed to sources other than fire. We have demonstrated that it is possible to produce accurate forecasts of next-day hourly ozone levels in the Sierra Nevada, CA, during fire season.
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