Effect of an organic amendment on availability and bio-accessibility of some metals in soils of urban recreational areas

A composted biosolid from wastewater treatment was added to soils of two public parks of Sevilla, and successive samples were taken during one year. In one of the parks, a second addition of biosolid was carried out after the first year. The soil contents in metals (pseudo-total) and their plant-available and oral bio-accessible fractions were significantly altered when the soils were amended with biosolid. Increase of the bio-accessible metal contents represents a deterioration of the environmental quality of recreational areas, where hand-to-mouth transfer of pollutants to children is likely to occur, although part of the metals added might be leached by rainfall or irrigation. The limits established in several countries for metal contents of soils in recreational areas are often exceeded after application of the biosolid. A careful study of the metal contents of recycled wastes is thus recommended before being used for green area maintenance.     

The bioaccumulation and translocation of Fe,Zn, and Cu in species of mushrooms from <Emphasis Type="Italic">Russula</Emphasis> genus

Introduction  

Many previous studies revealed a high ability of mushrooms to accumulate heavy metals from environment. This paper concerns the capacity of some wild macromycetes belonging to Russula genus to accumulate heavy metals in natural condition of pH (between 6.5 and 6.8) and the pattern of metal translocation in the fruiting body.     

Distribution of polychlorinated biphenyls in both products and by-products of a mussel shell incinerator facility

Purpose  

Solid waste incineration has recently attracted much attention because the combustion process involved produces highly toxic organohalogen contaminants such as dioxin-like polychlorinated biphenyls (DL-PCBs) present in fly ash. This has raised the need for simple, rapid, accurate methods for monitoring PCBs in ash samples.     

Identification of carbonaceous geosorbents for PAHs by organic petrography in river floodplain soils

Organic petrographic analysis was applied to provide direct information on carbonaceous geosorbents for PAHs in river floodplain soils. The anthropogenic OM group (primarily coal and coal-derived particles) displayed large volume amounts for all the soil samples. Distinct PAH concentrations with similar PAH distribution patterns were determined in grain size and density fractions for each sample. Two-ring PAHs had stronger correlation to organic carbon (OC) than black carbon (BC) contents, while heavier PAHs showed correlation to BC, rather than OC. In this study, we combined grain size and density separation, PAH determinations, TOC and BC measurements, and organic petrographic identification, and concluded that two-ring PAHs in soils were associated to coal particles. Other heavier PAHs could be more controlled by black carbon (BC), which were mostly coal-derived particles from former coal mining and coal industrial activity.     

Application of fluorescence in situ hybridization technique to detect simazine-degrading bacteria in soil samples

We propose a new approach to evaluate the natural attenuation capacity of soil by using fluorescence in situ hybridization (FISH). A specific oligonucleotide probe AtzB1 was designed based on the sequence data of the atzB gene involved in the hydrolytic deamination of s-triazines; this gene, located in a multiple copy plasmid was detected by the optimized FISH protocol. Two agricultural soils (Lodi and Henares) with a history of simazine treatments, and two natural soils (Soto and Monza), without previous exposure to simazine, were studied. AtzB1 probe-target cells were found only in the agricultural soils and, in a greater percentage, in the Lodi soil, compared to the Henares one. Moreover, the greatest percentage of AtzB1 probe-target cells in Lodi was accompanied by a greater mineralization rate, compared to the Henares soil. The FISH method used in this study was suitable for the detection of simazine-degrading bacteria and could be a useful indicator of the potential of soil bioremediation.     

Performance evaluation of a biotrickling filter treating a mixture of oxygenated VOCs during intermittent loading

Laboratory scale-studies on the biodegradation of a 1:1:1 weight mixture of three oxygenated volatile organic compounds (VOCs), ethanol, ethyl acetate, and methyl-ethyl ketone (MEK) in a biotrickling filter (BTF) were carried out using two identically sized columns, filled with different polypropylene rings. The performance of the BTFs was examined for a period of 10 months applying several operational strategies. Similar performance was obtained for both supports. Intermittent flow rate of trickling liquid was shown beneficial to improve the removal efficiency (RE). Continuous feeding of VOC resulted in an excessive accumulation of biomass so high pressure drop was developed in less than 20-30 d of operation. Intermittent VOC loading with night and weekend feed cut-off periods passing dry air, but without addition of water, was shown as a successful operational mode to control the thickness of the biofilm. In this case, operation at high inlet loads (ILs) was extended for more than 75 d maintaining high REs and low pressure drops. Outlet emission concentrations lower than 100 mg Cm(-3) were obtained for ILs up to 100 g Cm(-3)h(-1) working at 15s of empty bed residence time. The most easily biodegradable compounds ethanol and ethyl acetate were used primarily than MEK. After a 3-wk-starvation period, the system performance was almost restored since the first d of operation, being the removal of the less biodegradable compound, MEK, partially deteriorated.     

Occurrence of coal and coal-derived particle-bound polycyclic aromatic hydrocarbons (PAHs) in a river floodplain soil

A PAH contaminated river floodplain soil was separated according to grain size and density. Coal and coal-derived particles from coal mining, coal industry and coal transportation activities were identified by organic petrographic analysis in our samples. Distinct concentrations of PAHs were found in different grain size and density fractions, however, similar distribution patterns of PAHs indicated similar sources. In addition, although light fractions had the mass fraction by weight of less than 5%, they contributed almost 75% of the total PAHs in the soil. PAH concentrations of all sub fractions showed positive correlation with their TOC contents. Altogether, coal and coal-derived particles that were abundant in light fractions could be the dominant geosorbents for PAHs in our samples.     

Biochemical mechanisms of resistance in Daphnia magna exposed to the insecticide fenitrothion

Resistance to fenitrothion and enzyme activities associated with the toxicity and metabolism of organophosphorus insecticides were measured in three genetically unique Daphnia magna clones collected from rice fields of Delta del Ebro (NE Spain) during the growing season and a lab sensitive clone. The studied clones showed up to sixfold differences in resistance to fenitrothion. The lack of correlation between in vitro sensitivity of acetylcholinesterase (AChE) to fenitrooxon and resistance to fenitrothion indicated that insensitivity of AChE to the most active oxon metabolite was not involved in the observed differences in resistance. Inhibition of mixed- function oxidases (MFOs) by piperonyl butoxide (PBO) increased the tolerance to fenitrothion by almost 20-fold in all clones without altering their relative ranking of resistance. Conversely, when exposed to fenitrooxon, the studied clones showed similar levels of tolerance, thus indicating that clonal differences in the conversion of fenitrothion to fenitrooxon by MFOs were involved in the observed resistance patterns. Despite that resistant clones showed over 1.5 higher activities of carboxilesterase (CbE) than sensitive ones, toxicity tests with 2-(O-cresyl)-4H-1,3,2-benzodioxaphosphorin-2 oxide, which is a specific inhibitor of these enzymes, evidenced that this system only contributed marginally to the observed clonal differences in tolerance. Glutathione-S-transferases activity (GST) varied across clones but not under exposure to fenitrothion, and was only related with tolerance levels in the field clones. In summary, our results indicate that MFO mediated differences on the bio-activation of the phosphorotionate OP pesticide to its active oxon metabolite contributed mostly in explaining the observed moderate levels of resistance, whereas the activities of CbE and GST had only a marginal role.     

Prenatal sonographic appearance of foramina parietalia permagna

Foramina parietalia permagna (FPP) is an extremely uncommon congenital defect, inherited as an autosomal dominant condition. Its characteristics are two symmetrical orifices in the parietal bones (not of fixed size) on both sides of the midline. This defect does not affect either the psychic or the physical development of the affected person. This paper describes the sonographic appearance of FPP in utero as an enlargement of the posterior fontanelle.     

Temperature dependency of chlorobenzene bioaccumulation in phytoplankton

Chlorobenzene bioconcentration factors for Scenedesmus spp measured by batch equilibration, increased with temperature between 4.5 and 27.6 °C. A thermodynamic analysis suggests that the bioconcentration is driven by an entropy gain. Slopes of LogBCF-logK_ow relationships increased with temperature. These results agree with earlier reports for the analogous bioconcentration to fish.