Environmental Contamination and Toxicology

Degradation of Bisphenol A in Natural and Artificial Marine and Freshwaters in Turkey Abstract Bisphenol A (BPA), one of the important synthetic chemicals, has been produced at high volumes since the 1960s. These chemicals are commonly detected in the marine and freshwater environments; however, their transformation in aquatic environments depends on many parameters. This study aims to investigate the degradation of BPA in marine and freshwaters under different conditions in terms of microbial degradation, photodegradation, and temperature effect. The results showed that BPA content in samples prepared from the artificial waters did not change significantly in 150 days. BPA concentrations in natural river water started to degrade after day 50, and the degradation rate was faster for the samples at 25°C than ones at 4°C. In natural seawater samples, there was no degradation detected in 150 days at 4°C and 25°C. However, samples prepared in natural seawater, kept outside, and exposed to over 40°C temperature showed degradation after day 50. A treatment exposed to the sunlight showed a higher degradation rate, indicating the additive/synergistic role of the photodegradation. Our study suggests that high temperatures ( > 25°C) are required for BPA degradation in seawater. River water is more potent than seawater for BPA degradation. It is suggested that BPA contamination in a marine environment could be more persistent than in a freshwater environment.

Spatial Distribution and Congener Profiles of Polybrominated Diphenyl Ethers in Surface Sediment from Sanmen Bay and Xiamen Bay, Southeast China Abstract Coastal areas are influenced by anthropogenic input of a variety of organic pollutants, among which polybrominated diphenyl ethers (PBDEs) represent an important group. In the present study, we investigated the contamination status of PBDEs in surface sediment from two economically important Bays in Southeast China, Sanmen Bay (SMB; n = 29) and Xiamen Bay (XMB; n = 10). Concentrations of ∑PBDEs ranged from 2.2 to 78.5 ng/g dw (median 5.7 ng/g dw) in SMB and 7.9–276.0 ng/g dw (median 43.5 ng/g dw) in XMB, respectively. A nearshore-offshore decreasing trend was observed for both ∑PBDEs and BDE-209 concentrations, indicating strong urban influences. Although the current levels would not produce any significant impact on benthos and aquatic ecosystems of the studied regions, continuous monitoring is needed to understand the temporal trends of contamination in the important coastal waters and whether sediment-associated PBDEs constitute a potential source to aquatic ecosystems.

Phytoremediation of Three Herbaceous Plants to Remove Metals from Urban Runoff Abstract Phytoremediation experiments were carried out to assess the ability of different herbaceous buffer strips to absorb metals. Results revealed the Medicago sativa buffer strip had the best removal capacity for copper, lead, and cadmium in the runoff and seepage flow. Copper and lead content in M. sativa were significantly higher than in Lolium perenne and Poa pratensis (p < 0.05). Cadmium content in P. pratensis was significantly higher than in L. perenne and M. sativa(p < 0.05). Total accumulation of copper and lead in M. sativa buffer strips was 13.45 mg kg−1 and 1.01 mg kg−1, respectively. Total cadmium accumulation was approximately 0.50 mg kg−1 in both M. sativa and P. pratensis. Overall, results indicated that using M. sativa in the buffer strips was optimal for the remediation of copper, lead, and cadmium in sewage water.

Cytochrome P450 and Glutathione-S-Transferase Activity are Altered Following Environmentally Relevant Atrazine Exposures in Crayfish ( Faxonius virilis ) Abstract The herbicide atrazine is heavily applied in the U.S. Midwest to control broadleaf weeds. It enters local streams and rivers through runoff and seepage, and exposure can affect non-target aquatic organisms, like crayfish. We examined sublethal effects of atrazine on the expression and activity of the detoxification enzymes cytochrome P450 (CYP450) and glutathione-S-transferase (GST) in crayfish. Crayfish were exposed to 0, 10, 40, 80, 100 and 300 ppb atrazine for 1, 2, 4, 7 and 10 days. Their hepatopancreas was collected and CYP450 expression and GST activity was analyzed. Atrazine exposure caused differential expression and activity of CYP450 and GST. CYP450 expression varied over exposure concentrations and time. Further, GST activity significantly increased following a 2 day, 10 ppb exposure to atrazine and a 300 ppb atrazine exposure for all days tested. We found that atrazine detoxification is a dynamic process that changes with the length and intensity of atrazine exposure.

Trace Metal Accumulation in Trigonella foenum - graecum Irrigated with Wastewater and Human Health Risk of Metal Access Through the Consumption Abstract The aim of the present research was to determine the trace metal accumulations in Trigonella foenum-graecum irrigated with three different water regimes (ground water, canal water and sugar mill water). Also, transfer factors, pollution load indices, and health risk indices were assessed to evaluate metal transport and accumulation through the food chain. The analysis was conducted by Atomic Absorption Spectrophotometer (Shimadzu model AA-6300) to evaluate the concentration of metals in water, soil and vegetables. Trace metal concentrations in water samples ranged from 0.84 to 1.67, 0.42 to 0.72, 0.45 to 0.85, 2.51 to 9.99, 1.21 to 1.92, 1.82 to 9.98 and 0.64 to 0.91 mg/kg for Cd, Cr, Cu, Fe, Ni, Zn and Mn, respectively. The mean metal concentrations in soil samples were determined as 0.25, 0.86, 0.96, 3.37, 0.4, 0.44 and 2.31 mg/kg for Cd, Cr, Cu, Fe, Ni, Zn and Mn, respectively. Trace metal accumulations in T. foenum-graecum samples gathered from where soil samples were taken are as follows: The contents of Cd, Cr, Cu, Fe, Ni, Zn and Mn ranged from 0.48 to 1.06, 0.11 to 0.35, 0.15 to 0.29, 1.43 to 8.39, 0.39 to 0.54, 2.1 to 3.05 and 0.42 to 0.47 mg/kg, respectively. Statistical analyses showed that the treatments have non-significant effect (p > 0.05) on concentrations of metals in T. foenum-graecum samples collected from three sites for Ni, Cr, Cu, Zn and Mn and significant effect on Fe and Cd.

Heavy Metal Atmospheric Deposition Study in Moscow Region, Russia Abstract The air quality in north-eastern part of Moscow region was evaluated by trace metals atmospheric deposition using moss Pleurozium schreberi as bioindicator. Thirty six elements were determined in analyzed samples by Neutron activation analysis and Atomic absorption spectrometry. Principal component analysis was used to identify and characterize different pollution sources. Maps showing the geographical distribution of the factor scores were built using ArcGis software. Median values of the elements studied were compared with data obtained for other regions in Russia. The present survey showed that industrial activity, thermal power plants and transport still have the largest anthropogenic impact on air pollution in studied region.

Correction to: Measurements and Distribution of Atmospheric Particulate‑Bound Mercury: A Review The original version of this article unfortunately contained a mistake in units.

Current Research Advancements in Basic and Applied Soil Remediation in China

The Adsorption Behavior of Atrazine in Common Soils in Northeast China Abstract The objective of this study was to evaluate the adsorption capacity of atrazine and the effects of different environmental conditions such as temperature, pH, Ca2+ and biochar on the adsorption characteristics of atrazine in different types of soil using the intermittent adsorption method. The kinetic experiment showed that the adsorption of atrazine in albic, black and saline–alkaline soils reached equilibrium within 24 h. In the thermodynamics experiment, the Freundlich model effectively described the adsorption characteristics of atrazine in all three types of soil, indicating that the adsorption process forms multi-molecular layers. Lower soil pH conditions were more favorable for the absorption of atrazine. The addition of appropriate concentrations of Ca2+ or biochar could promote the adsorption of atrazine by the soil. Biochar could promote the fixation of atrazine in soils.

Effect of Nano-Carbon Black Surface Modification on Toxicity to Earthworm ( Eisenia fetida ) Using Filter Paper Contact and Avoidance Test Abstract Engineered nanomaterials (NMs) may enter the soil through various channels and pose potential harm to soil animals, especially those proactively applied for soil heavy metal remediation. Effects of nano-carbon black (CB) and surface modified carbon black (MCB) on catalase (CAT) activity and malondialdehyde (MDA) content in earthworms exposed on filter paper for 48 h were tested. Avoidance test was used to determine hazard of soil treated with 0.015% and 1.5% CB and MCB. Surface properties of NMs were also characterized. MCB has a significant effect on CAT activity at 70 and 1000 mg/L (1.1 and 15.7 µg/cm2), but has no impact on MDA content in earthworm. Strongly avoidance behavior of worms was also found in soil added 1.5% MCB. Negative charges and oxygen functional groups increased for MCB and its adverse effect on earthworm was higher than CB. The application of MCB in soil remediation warrants more attention.