Amphibians, particularly frogs, are increasingly used as bioindicators of contaminant accumulation in pollution studies. Their use for field scientific purposes is limited because most frog species are endangered and protected in most countries; killing of specimens are not allowed. The aim of our study was to work out and assess a method by which the elemental contents of frog bones could be estimated effectively based on the toe bones. For this purpose, Rana esculenta L. individuals were collected from an urban pond in Debrecen city (Hungary). The following large bones were also analysed: skull, spinal, femur, tibia-fibula, tarsal bones, metatarsus, humerus and digits from front and hind limbs. In the bones, P, Ca, Mg, Mn, Na, S and Zn elements were measured. The elemental contents of large bones were significantly correlated with bones weight in the case of each element. The elemental contents of phalanges were also estimated based on the large bones. The measured and the estimated elemental contents of phalanges were not different significantly based on the tibia-fibula, metatarsalis bones, front and hind limb digits. Elemental analysis based on phalanges adds a further way of use of phalanges. Frogs using their phalanges could be useful indicators in the assessment of environmental contamination.

Many soils derived from pyrite mines spoils are acidic, poor in organic matter and plant nutrients, contaminated with trace elements, and support only sparse vegetation. The establishment of a plant cover is essential to decrease erosion and the contamination of water bodies with acid drainage containing large concentrations of trace elements. We tested the application of compost and polyacrylate polymers to promote the growth of indigenous plant species present in the mine area. Soil treatments consisted of unamended soil (control), soil with mineral fertilizers only, soil with fertilizer plus compost, soil with fertilizer plus polyacrylate polymers, and soil with fertilizer plus both amendments. Half of the soil was grown with Briza maxima L. (greater quaking grass), Chaetopogon fasciculatus (Link) Hayek (chaetopogon), and Spergularia purpurea (Persoon) G. Don fil. (purple sandspurry), while the remainder was left bare. In the absence of plants, the greatest improvements in soil conditions were obtained by the application of both amendments, which was associated with the greatest values of protease, acid phosphatase, and β-glucosidase, whereas the activity of cellulase and microbial respiration were similar in soil amended with compost or polymer. Dehydrogenase activity was greatest in soil with compost (with or without polymer), whereas urease activity was impaired by both amendments. In the presence of plants, the application of both amendments led to the greatest activities of protease, urease, β-glucosidase, cellulase, and microbial respiration, but acid phosphatase was mainly enhanced by polymer and dehydrogenase was increased by compost. Plant growth was stimulated in all treatments compared with unamended soil, but the greatest value for total accumulated biomass was obtained in fertilized soil receiving both amendments. However, species responded differently to treatment: while the growth of B. maxima was greatest in soil with compost and polymer, the growth of C. fasciculatus responded better to soil with compost, and S. purpurea grew better in polymer-amended soil. The amendments tested improved the quality of a mine soil and stimulated plant growth. However, botanical composition likely changes over time with amendments, and this needs to be considered when a large scale application of amendments is projected.

In this paper, the effect of nitrogen addition on the aerobic bioremediation of a diesel-contaminated soil was studied. Soil was artificially contaminated with diesel at an initial 2% concentration (on a dry soil basis). Nitrogen was added as NH₄Cl in a single load at the start of the experiment at concentration levels of 0, 100, 250, 500, 1,000, and 2,000 mg N/dry kg soil, and uncontaminated and unamended soil O₂ consumptions were studied. Diesel degradation was indirectly studied via measurements of O₂ consumption and CO₂ production, using manometric respirometers. Results showed that the 250 mg N/dry kg concentration resulted in the highest O₂ consumption among all runs, whereas O₂ consumption was reduced by N additions greater than 500 mg N/dry kg. Zero to 0.6 order degradation kinetics appeared to prevail, as was calculated via the oxygen consumption rates. A theoretical biochemical reaction for diesel degradation was developed, based on measurement of the final diesel concentration in one of the runs. According to the stoichiometry, the optimal N requirements to allow complete diesel degradation should be approximately 0.15 g N/g diesel degraded or 1,400 mg N/dry kg of soil, based on the initial diesel concentration used in this study. This implies that N should be added in incremental loads.

A meso-scale pilot plant was set up to test the efficiency of a phytoremediation technique applied to slightly contaminated marine sediments dredged from the port of Livorno (central Italy). The technique applied involved the use of plants (a grass species, Paspalum vaginatum and a shrub species, Tamarix gallica) and earthworms (Eisenia foetida sp.) in order to recreate an active ecosystem in which plants, micro- and macroorganisms could interact with each other through the rhizosphere, for the adsorption, extraction and/or degradation of pollutants. This system enables plants to grow in a fine textured and salt medium highly unsuitable for plant species, and a physical, chemical and biological amelioration of the matrix was observed at the end of the experimentation (after 9 months). The sediment was bio-physically pre-conditioned by mixing it with calcareous material from excavating activities (5:1 v/v) and applying green compost. The presence of microorganisms in the rhizosphere and the earthworms produced a reduction by about 50% of the initial total petroleum hydrocarbon content. The use of a natural chelator with phyto-hormonal properties (humic substances) showed their capability of forming stable complexes, especially with Pb, and their contribution as an agronomic fertiliser. The combined effect of the P. vaginatum and T. gallica in the extraction of heavy metals from the sediment showed promisingly high percentages of metal effectively extracted in comparison with its available fraction (e.g. available Ni = 6.2%; Ni extracted = 15.7%). The technique proposed could be promising for an operational re-use of dredged marine sediments for agricultural purposes, a suitable final destination for the great majority of these contaminated materials from rivers and harbour docks.

The effect of in situ immobilization of lead (Pb) and arsenic (As) in soil with respectively phosphate and iron is well recognized. However, studies on combined Pb and As-contaminated soil are fewer, and assessment of the effectiveness of the immobilization on mobility and bioaccessibility is also necessary. In this study, a Pb and As-contaminated soil was collected from an abandoned lead/zinc mine in Shaoxing, Zhejiang province of China, which has been treated with three phosphates, i.e., calcium magnesium phosphate (CMP), phosphate rock, and single super-phosphate (SSP) for 6 months in a field study. The ferrous sulfate (FeSO₄) at 20 g kg⁻¹ was then amended to the soil samples and incubated for 8 weeks in a greenhouse. The solubility and bioaccessibility tests were used to assess the effectiveness of the in situ immobilization. The result showed that phosphates addition decreased the concentrations of CaCl₂-extractable Pb; however, the concentrations of water-soluble As increased upon CMP and SSP addition. With the iron addition, the water-soluble As concentrations decreased significantly, but CaCl₂-extractable Pb concentrations increased. The bioaccessibility of As and Pb measured in artificial gastric and small intestinal solutions decreased with phosphate and iron application except for the bioaccessibility of As in the gastric phase with SSP addition. Combined application of phosphates and iron can be an effective approach to lower bioaccessibility of As and Pb, but has opposing effects on mobility of As and Pb in contaminated soils.

The goal of this work was to investigate the occurrence of emerging contaminants in drinking water of the city of Campinas, Brazil. Tap water samples were analyzed using SPE-GC-MS for 11 contaminants of recent environmental concern. Six emerging contaminants (stigmasterol, cholesterol, bisphenol A, caffeine, estrone, and 17β-estradiol) were found in the samples. The latter two were detected only during the dry season, with concentrations below quantification limits. Stigmasterol showed the highest average concentration (0.34 ± 0.13 µg L⁻¹), followed by cholesterol (0.27 ± 0.07 µg L⁻¹), caffeine (0.22 ± 0.06 µg L⁻¹), and bisphenol A (0.16 ± 0.03 µg L⁻¹). In Campinas, where surface drinking water supplies receive large amounts of raw sewage inputs, the emerging contaminants levels in drinking waters were higher than median values compiled for drinking and finished water samples around the world.

In this research, geological and hydrogeological studies were conducted to determine the source of high arsenic levels in the surficial aquifer of Simav Plain, Kutahya, Turkey. One of the two aquifer systems isolated in the study area was a deep confined aquifer composed of fractured metamorphic rocks that supply hot geothermal fluid. The other one was an unconfined alluvial aquifer, which developed within the graben area as a result of sediment deposition from the highlands. This aquifer serves as the primary water resource within the plain. A water quality sampling campaign conducted in 27 wells drilled in the surficial aquifer has yielded an average arsenic concentration of 99.1 µg/L with a maximum of 561.5 µg/L. Rock and sediment samples supported the fact that local metamorphic rocks contained significant amounts of sulfur minerals where arsenic-containing lenses are present inside. It was also determined that a Cu-Pb-Zn mine was operated in the past in the same formation. Arsenic-containing wastes of this mine were deposited near the Simav district center in an uncontrolled manner. This mined formation had arsenic levels reaching to levels as high as 660 mg/kg, which was found out to be the highest arsenic level in the area. Another potential arsenic source in the study area was the geothermal fluid that was used extensively in three geothermal fields with levels reaching to levels as high as 594 µg/L. Uncontrolled discharges of waste geothermal fluid and overexploitation of groundwater were also found to contribute to arsenic pollution in surface/subsurface waters of the plain. Thus, natural sources and anthropogenic influences of arsenic were found to create high concentrations in local water reserves of the area and influence human health. Consequently, death statistics from the 1995 to 2005 period collected from the area has revealed increased rates of gastrointestinal cancers above Turkish average.

The objectives of this study were algal control and health assessments in a temperate eutrophic reservoir. Laboratory and mesocosm-scale in situ top-down biomanipulation experiments using planktivorous fishes and filter-feeding macroinvertebrates were conducted along with identification of the limiting nutrient using nutrient enrichment bioassays (NEBs), and ecosystem health evaluation based on the modified index of biological integrity model (Reservoir Ecosystem Health Assessment; REHA). Nutrients and N/P ratio analyses during 5 years revealed that the reservoir was in a eutrophic-hypertrophic state and that the key limiting nutrients, based on the NEBs, varied among seasons. Reservoir trophic guilds indicated declines in sensitive and endemic fish species and dominance of tolerant omnivores. Model values from multimetric REHAs averaged 25.8, indicating that the ecological health was in “fair to poor” condition. Overall microcosm biomanipulation tests suggested that macroinvertebrates, specifically Palaemon paucidens and Caridina denticulata, were effective candidates for phytoplankton control, compared to fishes. In situ mesocosm experiments revealed the highest removal rates with bluegreen algae and a phytoplankton size fraction of 2-19 μm (R e > 90%, Mann-Whitney U = 64.5-74.0, p < 0.01), the dominant fractions in the reservoir. Our biomanipulation technique may provide a key tool for efficient management and restoration of eutrophied reservoirs.

Trace elements, especially those associated with fine particles in airborne particulate matter (PM), may play an important role in PM adverse health effect. The aim of this paper is to characterize elements in a wide particle size range from nano (57-100 nm) to fine (100-1,000 nm) and to coarse (1,000-10,000 nm) fractions of two urban PM samples collected in Ottawa. Size-selective particle sampling was performed using a micro-orifice uniform deposit impactor, and element concentrations were determined in each different size fraction by inductively coupled plasma-mass spectroscopy. A general trend of increasing element concentration with decreasing aerodynamic diameter was observed for elements V, Mn, Ni, Cu, Zn, Se, and Cd, indicating they were predominately concentrated in the nanoparticle size range. Other elements including Fe, Sr, Mo, Sn, Sb, Ba, and Pb were predominately concentrated in the fine-size range. Increased concentration of elements in the nano and fine particle size range is significant due to their ability to penetrate into the deepest alveolar area of the lungs. This was confirmed by the calculation of median concentration diameters, which were less than 800 nm for most of the investigated elements. Particle size distribution and element correlation analysis suggest that the elements concentrated in the nano- and fine-size fractions originated mainly from vehicular combustion and emission. Long-range airborne transport and soil or road dust resuspension may also contribute. Particle size had an important effect on element bioaccessibility for the studied urban PM samples showing a general trend of increasing element bioaccessibility with decreasing particle size. These results emphasize the importance of acquiring information on nano and/or fine PM-bound elements and their bioaccessibilities for accurate element and PM exposure assessment.

The upper Great Egg Harbor River watershed in New Jersey's Coastal Plain is urbanized but extensive freshwater wetlands are present downstream. In 2006-2007, studies to assess levels of total mercury (THg) found concentrations in unfiltered streamwater to range as high as 187 ng/L in urbanized areas. THg concentrations were <20 ng/L in streamwater in forested/wetlands areas where both THg and dissolved organic carbon concentrations tended to increase while pH and concentrations of dissolved oxygen and nitrate decreased with flushing of soils after rain. Most of the river's flow comes from groundwater seepage; unfiltered groundwater samples contained up to 177 ng/L of THg in urban areas where there is a history of well water with THg that exceeds the drinking water standard (2,000 ng/L). THg concentrations were lower (<25 ng/L) in unfiltered groundwater from downstream wetland areas. In addition to higher THg concentrations (mostly particulate), concentrations of chloride were higher in streamwater and groundwater from urban areas than in those from downstream wetland areas. Methylmercury (MeHg) concentrations in unfiltered streamwater ranged from 0.17 ng/L at a forest/wetlands site to 2.94 ng/L at an urban site. The percentage of THg present as MeHg increased as the percentage of forest + wetlands increased, but also was high in some urban areas. MeHg was detected only in groundwater <1 m below the water/sediment interface. Atmospheric deposition is presumed to be the main source of Hg to the wetlands and also may be a source to groundwater, where wastewater inputs in urban areas are hypothesized to mobilize Hg deposited to soils.