Trace Elements in Surface Soils and Megascolecidae Earthworms in Urban Forests Within Four Land-Uses Around Poughkeepsie, New York, USA Abstract Amynthas agrestis and Metaphire hilgendorfi are being distributed across North America with unknown ecosystem impacts. Forest soils in urban areas sequester trace elements and earthworms may be bioaccumulating them. This study examined Cd, Cr, Co, Cu, Mn, Ni, Pb, V, and Zn in soils and earthworm tissues at 28 urban forest sites in and surrounding Poughkeepsie, NY, USA. Megascolecidae were present at 22 sites with means of 12 to 27 individuals m−2 and 4 to 12 dry weight g m−2. Urban forest soils within commercial uses had Mn, Pb, and Zn concentrations higher than within residential and agricultural uses. Earthworm trace element concentrations were poorly predicted by their respective soil concentrations, except for Pb. Urban forests in commercial uses and land-preserves, earthworm Cd and Pb concentrations were at or above concentrations known to negatively impact small mammal and bird health ( > 10 mg kg−1) with Co and V approaching toxic concentrations.

Enantioselective Behavior of Chiral Difenoconazole in Apple and Field Soil Abstract Difenoconazole is a universal chiral fungicide which is widely used in apples. Recently, it is still employed as racemic mixtures without distinction of the enantiomers, which may lead to an incomplete risk assessment. Here, we analyzed the stereoselective degradation of difenoconazole in apple fruits and open-field soil using an HPLC–UV system. Different trends were established in various apple varieties under identical environmental conditions. No significant differences were found in its enantioselectivity of the degradation processes applied in the field soil of an apple orchard. However, preferential dissipation of (2R,4R)-difenoconazole and (2R,4S)-difenoconazole was observed in Hanfu and Fuji apples, resulting in the enrichment of stereoisomers of (2S,4S)-difenoconazole and (2S,4R)-difenoconazole. Meanwhile, no significant enantioselectivity was detected in Huahong apples. The present study will provide additional information that contributes to the comprehensive evaluation of the risks posed by the application of chiral difenoconazole in agricultural production practices.

Comparison of Maternal and Embryonic Trace Element Concentrations in Common Thresher Shark ( Alopias vulpinus ) Muscle Tissue Abstract This study compared the concentration of essential (Co, Cr, Cu, Fe, Mn, Ni, Se, Zn) and nonessential (Ag, As, Cd, Hg, Pb) trace elements in the muscle tissue of a pregnant common thresher shark (Alopias vulpinus) to the concentration in the three embryos. With the exception of Ag, Cd, Cr, and Ni which were below the detection limit, all other elements accumulated in the embryo muscle tissue. The Se:Hg molar ratios in the embryos averaged 9.8, indicating that Se may have a protective role against Hg toxicity during this early life stage. Maternal transfer as a source of trace elements in sharks should not be overlooked and future studies need to focus on how reproductive strategy influences this process.

Are Oxidative Stress Biomarkers Sensitive to Environmental Concentrations of Chlorpyrifos Exposed to the Freshwater Crab, Zilchiopsis collastinensis (Decapoda; Trichodactylidae)? Abstract Global trends in pesticide use can increase aquatic pollution and affect resident fisheries. Crabs exposed to organophosphate pesticides, such as chlorpyrifos, may increase production of reactive oxygen species (ROS), affecting the pro-oxidant/antioxidant balance. Zichiopsis collastinensis crabs were exposed to environmentally relevant concentrations of chlorpyrifos (0.1 and 0.5 µg L−1). Effects on the oxidative stress enzymes catalase, superoxide dismutase, glutathione S-transferases, glutathione reductase, and on thiobarbituric acid reactive substances and hydrogen peroxide concentrations were evaluated at four intervals during 96 h exposures. Exposures caused decreased GST activity and increased H2O2 levels in gills. There were modifications of GST, CAT and SOD activities in the hepatopancreas after 12 h of exposure, and an increase of H2O2 levels at every exposure interval observed. The present study proved that chlorpyrifos lead to oxidative stress in Z. collastinensis. However other enzymatic/non-enzymatic responses should be further investigated in order to be included as part of a battery of biomarkers, together with H2O2 levels, which is a parameter highly recommended to be taken into account.

Effects of Cadmium Bioavailability in Food on Its Distribution in Different Tissues in the Ground Beetle Pterostichus oblongopunctatus Abstract In most laboratory studies with oral exposure of terrestrial invertebrates to metals an artificial food, which is easy to handle, is used. The bioavailability of metals from this artificial food may, however, be much higher than from more field relevant food sources. Such differences may affect toxicokinetic processes in different tissues. To test the effect of bioavailability of Cd in food on Cd toxicokinetics and internal distribution in terrestrial invertebrates, we performed the experiment using the ground beetle Pterostichus oblongopunctatus exposed to Cd via food differing in their soluble Cd pool. We showed that in carabids Cd accumulation and elimination pattern in different tissues is not governed by the metal availability in food.

Distribution of Surfactants in the Sea Surface Microlayer and Sub-surface Water in the Melaka River Estuary Abstract This study determines the levels of surfactants at 12 stations located in the Melaka River Estuary. This river estuary is located within a tourism area of Melaka Historical City. The concentrations of anionic and cationic surfactants in the sea surface microlayer (SML) and sub-surface water (SSW) were determined by using two colorimetric methods, methylene blue active substances (MBASs) and disulphine blue active substances (DBASs), respectively. The results showed that cationic surfactants as DBAS (ranging between 0.19 and 0.25 μmol L−1) dominated the concentrations of surfactants in SML. The enrichment factor (Ef) between MBAS and DBAS in the SML and SSW ranged between 1.0 and 2.0, and 1.0 to 1.4, respectively. There was no significant correlation (p > 0.05) between MBAS and DBAS for both SML and SSW. Nevertheless, there were strong correlations (p < 0.05) between both MBAS and DBAS in the SML and SSW. The results showed the potential contribution of degradation processes of organic substances microorganisms in SSW towards the concentrations of surfactants in SML. Compared to previous studies, tourism-related activities may influence the concentrations of surfactants, especially DBAS, in this river estuary.

Reserve Mobilization, Membrane Damage and Solutes Leakage in Fenugreek Imbibed with Urban Treated Wastewater Abstract The study aimed to determine the impact of treated domestic wastewater on seed germination, seedling growth and reserve mobilization from Fenugreek (Trigonellafoenum graecum L.). Seeds were germinated by soaking in distilled water (H2O) or wastewater treated with various methods: activated sludge processes (T1), facultative lagoons treatment (T2) and dilution. Results show high levels of organic matter (OM), suspended solids (TSS) and nutrients in TWW (T2) than that of TWW (T1). The embryo length and biomass of fenugreek imbibed by TWW were higher in TWW (T2) compared with TWW (T1). There was more reduction in free amino acids and soluble sugar contents in fenugreek treated with TWW (T1) than treated by TWW (T2). Important solutes leakage is recorded by measuring electric conductivity during seed imbibition with TWW. Improving the quality of wastewater by dilution (50%) stimulated germination of seeds and the growth of the tested plant. Moreover, it significantly reduces the solutes leakage and enhanced seed metabolites accumulation.

Chemical Degradation of Sulfosulfuron in Aqueous Suspension of Rice and Wheat Straw Ashes Abstract Burning of wheat and rice straw on field, after crop harvest, is a quick, cheap and an easy way for land clearing. The ashes generated after burning are mixed with soils and due to their alkaline nature, they may affect the degradation of applied herbicides. Therefore, present paper reports degradation of sulfosulfuron in aqueous suspension of the wheat (WSA) and rice (RSA) straw ashes. The results suggested that both ashes significantly enhanced sulfosulfuron dissipation in water and effect was more with the RSA. The solution pH affected sulfosulfuron dissipation and in control buffers (no ash) herbicide degradation followed the order: acidic > alkaline > neutral. Addition of the RSA significantly increased sulfosulfuron degradation in buffers, but effect was more evident at neutral and alkaline pH. The study has relevance in assessing degradation of sulfosulfuron in soils where crop residues are burned for land clearing.

Toxicological Assessment of Intermediates in Natural Attenuation of p -Xylene to Marine Microalgae Abstract The toxic effects of p-xylene, 4-methylbenzyl alcohol, p-methyl benzaldehyde, and p-toluic acid on two marine microalgae (Phaeodactylum tricornutum Bohlin, and Skeletonema costatum) were investigated. p-Xylene was the most toxic to Pha. tricornutum with a 96 h EC50 value of 6.76 mg L−1. Based on the 96 h EC50 values for two microalgae, the toxicity of the four chemicals, in descending order, was: p-xylene, p-methyl benzaldehyde, 4-methylbenzyl alcohol, then p-toluic acid. The results showed that the toxicity of the transformed products of p-xylene was lower than that of p-xylene.

Effects of Heavy Metals Artificial Contamination on Porcellio laevis (Latreille, 1804) (Crustacea: Isopoda: Oniscidea) Abstract This study aimed at determining the competition of cadmium (Cd), lead (Pb), zinc (Zn) and copper (Cu) on their assimilation, on the food consumption and the growth of terrestrial isopod Porcellio laevis. Individuals were exposed to artificially contaminated litter of Quercus for 4 weeks and were weekly weighed. At the end of the experiment, the concentration of Cd, Pb, Zn and Cu in individuals were measured by atomic absorption spectrometry. Biological parameters such as growth, and bioaccumulation factor (BAF) were calculated and results from the various treatments were compared. Depending on metals, weight loss or gain were recorded for isopods during the four weeks of exposure. A weight loss was measured on individuals exposed to Cd-contaminated litter whereas a weight gain was highlighted for those exposed to the Zn-contaminated litter. BAF values revealed that P. laevis was macroconcentrator of Zn and Cu and deconcentrator of Cd and Pb.