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This feature article discusses the state-of-play of cyclic sulfinic acid derivative (sultines and cyclic sulfinamides) formation.

Immunophenotyping is proving crucial to understanding the role of the immune system in health and disease. High-throughput flow cytometry has been used extensively to reveal changes in immune cell composition and function at the single-cell level. Here, we describe six optimized 11-color flow cytometry panels for deep immunophenotyping of human whole blood. A total of 51 surface antibodies, which are readily available and validated, were selected to identify the key immune cell populations and evaluate their functional state in a single assay. The gating strategies for effective flow cytometry data analysis are included in the protocol. To ensure data reproducibility, we provide detailed procedures in three parts, including (1) instrument characterization and detector gain optimization, (2) antibody titration and sample staining, and (3) data acquisition and quality checks. This standardized approach has been applied to a variety of donors for a better understanding of the complexity of the human immune system.

Trace elements like copper and zinc are supplemented in swine feeds to suppress bacteria and/or promote growth. Due to low absorption rates, trace elements are highly concentrated in swine feces, posing a risk to soil and human health if applied to agricultural fields. In the present study, the concentrations of six trace elements (Cu, Zn, As, Cd, Pb, and Cr) in pig feed and feces were evaluated by sample analysis and data from the literature. The feed-to-feces and feces-to-compost enrichment factors of the trace elements were determined to back-calculate safe concentrations in feed needed to meet permissible trace element concentrations in organic fertilizers. The Cu and Zn concentrations in feeds were the highest, being statistically significantly higher in starter pig feeds than in grower-finisher feeds. Copper exceeded feed limits mainly in the feeds of finisher pigs and sows, while exceedance for Zn occurred in almost all feed samples. Concentrations above the limits were also observed for Pb and Cr impurities in mineral feed supplements. The highest Cu and Zn concentrations in feces were observed for starter pigs. Moreover, significant enrichment of trace elements from feeds to feces was found, with enrichment factors calculated as: 4.68-6.11 for Cu, 3.43-4.60 for Zn, 2.30-3.12 for As, 2.89-4.63 for Cd, 2.45-5.00 for Pb, and 3.32-5.00 for Cr. On this basis, the recommended calculated limits for Cu, Zn, As, Cd, Pb, and Cr in feeds for different ages of pigs were 41-53, 130-175, 2-3, 0.3-0.5, 5-10, and 15-23 mg/kg, respectively. Priority index calculations and the calculated recommended limits indicated that Cu in starter pig feeds and Cd in starter and breeding pig feeds should be prioritized for reduction to enable feces compost to be utilized safely in agricultural land amendment. Integr Environ Assess Manag 2022;18:978-987. © 2021 SETAC.

In this study, soils spiked with copper oxide nanoparticles (CuO NPs) or Cu(NO3)2 and aged as long as 90 days were utilized to investigate effect of soil properties and aging on oral and inhalation bioaccessibility of CuO NPs. Results showed that oral bioaccessibility of CuO NPs in gastric phase (GP) ranged from 70% to 84%, it significantly decreased to 50%–70% in intestinal phase (IP). The inhalation bioaccessibility of CuO NPs in artificial lysosomal fluid (ALF) ranged from 66% to 85%, and much higher than that in Gamble’s solution (GS, 3.3%–23%). By comparing CuO NPs to Cu(NO3)2 bioaccessibility, insignificant difference was found. The aging time (D15 and D90) had limited effect on their oral and inhalation bioaccessibility. CEC and free Al were positively and clay content was negatively correlated with CuO NPs inhalation bioaccessibility, while Cu(NO3)2 inhalation bioaccessibility decreased with increasing soil clay content and pH. Our findings provide an essential basis to evaluate the human health risks of CuO NPs.

Swine farms are one of the important sources of antibiotics in the environment. In this study, 42 samples of compound feed and feces of swine collected at different growth stages from intensive farms were evaluated for the occurrence and concentrations of three tetracyclines (TCs, namely oxytetracycline, chlortetracycline, and doxycycline) and three sulfonamides (SAs, namely sulfadiazine, sulfadimidine, and sulfamethoxazole). To check for other additional sources of antibiotic administration, ratios (R) of the measured and the predicted levels of each antibiotic excreted via feces were also estimated. Our results showed that the maximum concentration of TCs was 376,210 μg kg−1 and 541,020 μg kg−1 in the feeds and feces, respectively, both for oxytetracycline. In contrast, the highest concentration of SAs were 16.98 μg kg−1 for sulfadimidine in the feeds and 14.70 μg kg−1 for sulfadiazine in the feces. The concentrations of ΣTCs (sum of the three tetracyclines) in swine feeds and feces were found to be 1–4 orders of magnitude higher than those of ΣSAs (sum of the three sulfonamides). Approximately 36% of the R values were found to be greater than one, indicating other sources of administration such as injection and/or oral administration (via drinking water) may also contribute to the presence of antibiotics in feces. Most of the higher R values were found in starter pigs, which were generally administrated with antibiotics by multiple routes to prevent disease and promote swine growth. Our study suggests that comprehensive measures may be undertaken to control antibiotic use in intensive swine farms.

Nano copper oxide (CuO NP) was added to eight soils to study the effect of aging time of copper on the concentration of diethylenetriaminepentaacetic acid (DTPA)-extracted copper (DTPA-Cu), with bulk copper oxide (CuO BP) and copper nitrate [Cu(NO

After water-soluble nickel (Ni) is added to soils, its bioavailability/toxicity, isotopic exchangeability, and extractability decline over time. Two separate semi-mechanistic models (Sqrt-model and Ln-model), have been developed to predict short- and long-term aging of Ni added to soils. To continuously predict Ni aging in one model, a semi-mechanistic model (Erfc-model) was developed in the present study where the description of the diffusion process was based on a complementary error function. The Erfc-model for whole course aging predicted short- and long-term Ni aging continuously with regression coefficients (R2) of 0.87 and 0.94, which were comparable with the Sqrt-model (0.91) and Ln-model (0.89). Based on the Erfc-model, soil pH and aging time were two important factors influencing the Ni aging processes. An additional 45 soils covering short and long terms of aging were applied to validate the model. A strong correlation (R2 = 0.85) was found between the measured and the predicted lability of Ni in soils with root-mean-square-error (RMSE) of 8.97%, illustrating that the Erfc-model could continuously predict short- and long-term aging processes of Ni added to soils. The model could be used as an alternative to normalize ecotoxicological data for driving soil environmental quality standards.

Dissolution is the primary process affecting the bioavailability and toxicity of nanoscale copper oxide (nano-CuO) to plants and soil organisms. In this study, particle morphology, organic acid, and soil properties were considered to understand the dissolution characteristics of nano-CuO in soil solutions. The results showed that the copper ions (Cu2+) released from spherical nano-CuO (CuO NPs), tubular nano-CuO (CuO NTs), and spherical microsized CuO (CuO MPs) in the ten soil solutions were 26.6–4194.0 μg/L, 4.90–217.1 μg/L, and 10.8–326.0 μg/L, respectively. The concentration of Cu2+ was negatively correlated with the pH of the soil solution and positively correlated with the contents of dissolved organic carbon (DOC), aluminum, and manganese. Multivariate stepwise regression analysis indicated that the dissolution of CuO NPs could be well predicted by pH and DOC contents of the soil solutions. In the GD soil solution (acidic), 4- and 8-fold of the DOC content amendments significantly promoted the dissolution of the three sizes of CuOs, resulting in an increase of Cu2+ 4.55–11.3 and 5.67–16.2 times, respectively. In the CQ soil solution (neutral), 8-fold DOC amendments increase the release of Cu2+ 2.13–16.6 times. While in the SD soil solution (alkaline), promoting effect on the dissolution was only observed for nano-CuOs, with Cu2+ elevated by factors of 1.56–4.64 and 1.38–4.48. The amendments of Al3+ and Mn2+ in soil solution increased the amounts of Cu2+ 1.13–4.80 and 1.02–1.46 times in the GD soil solution. In comparison, no significant promoting effects were observed in CQ and SD soil solutions due to their stronger buffering capacities. These findings offer insight into the dissolution behavior of nano-CuOs in soils and be helpful to evaluate their environmental risks.

The human pathogenic bacteria (HPB) in animal feces may disseminate to agricultural soils with their land application as organic fertilizer. However, the knowledge about the impacts of different sources and rates of animal manures on the temporal changes of soil HPB remains limited, which hamper our ability to estimate the potential risks of their land application. Here, we constructed an HPB database including 565 bacterial strains. By blasting the 16 S rRNA gene sequences against the database we explored the occurrence and fate of HPB in soil microcosms treated with two rates of swine, poultry or cattle manures. A total of 30 HPB were detected in all of manure and soil samples. Poultry manure at the high level obviously improved the abundance of soil HPB. The application of swine manure could introduce concomitant HPB into the soils. Of which, Pseudomonas syringae pv. syringae B728a and Escherichia coli APEC O78 may deserve more attention because of their survival for a few days in manured soils and being possible hosts of diverse antibiotic resistance genes (ARGs) as revealed by co-occurrence pattern. Bayesian source tracking analysis showed that the HPB derived from swine manure had a higher contribution to soil pathogenic communities than those from poultry or cattle manures in early days of incubation. Mantel test together with variation partitioning analysis suggested that bacterial community and soil physicochemical properties were the dominant factors determining the profile of HPB and contributed 64.7% of the total variations. Overall, our results provided experimental evidence that application of animal manures could facilitate the potential dissemination of HPB in soil environment, which should arouse sufficient attention in agriculture practice and management to avoid the threat to human health.

Land application of animal manures is a major dissemination route for antibiotic resistance genes (ARGs) in agro-ecosystems, which are a potential risk to public health if they migrate into the food chain. Despite the fact that animal manure is a rich reservoir of ARGs our knowledge of the impacts of different types and amounts of animal manures on the temporal succession of a wide array of ARGs and potential ARG-hosts remains limited. Here, we constructed soil microcosms amended with two levels of swine, poultry or cattle manures to explore the time-course patterns of ARGs, mobile genetic elements (MGEs) including integrons and transposons, and bacterial communities. The high-throughput quantitative PCR detected 260 unique ARGs, and the application of all manure types, especially at the higher concentration (80 mg manure g−1 soil), significantly increased the diversity and abundances of ARGs and MGEs. The abundance of ARGs in manured soils declined over time, but was still higher than that in untreated soils after 120 days, indicating the persistence of ARGs in manured soils. The next-generation sequencing revealed a clear shift in the bacterial community compositions of manured soils during the incubation. Mantel test and network analysis revealed that the ARG profile was strongly correlated with the bacterial community compositions. Variation partitioning analysis, and structure equation models, further indicated that bacterial phylogeny played a primary role in shaping the ARG profiles in manured soils. However, the significant correlation between the abundances of MGEs and ARGs suggested that the potential effects of horizontal gene transfer on the persistence of ARGs should not be overlooked. In addition, soil properties, which were strongly affected by the added manures, could also affect the ARG patterns. These findings demonstrated the temporal patterns and dissemination risk of ARGs in manured soils, which might contribute to the development of effective strategies to minimise the spread of ARGs in agro-ecosystems.

To understand how Cd in different fractions contributes to Cd bioaccessibility by in vitro assays, Cd bioaccessibility in 12 contaminated soils was determined by four assays (UBM, SBRC, IVG, and PBET) and correlated with different Cd fractions based on a sequential extraction scheme. The Cd bioaccessibility in the gastric phase (GP) was high (35–107%, averaging at 77%), implicating high risk to human health, while it decreased to 19–88% averaging at 47% in the intestinal phased (IP). From the GP to IP, the reduction of extractable Cd (0.45–48 mg kg−1) and Fe (118–3884 mg kg−1) showed significant correlation (R = 0.54–0.74) via UBM, SBRC, and IVG, suggesting co-precipitation with Fe and/or sorption onto Fe oxides maybe responsible for decrease in Cd bioaccessibility. Although Cd bioaccessibility varied among assays, their results show some consistency based on their correlation in the GP (R = 0.56–0.90) and IP (0.34–0.73, excluding UBM-IP and PBET-IP). Sequential extraction data show that Cd was primarily associated with the exchangeable fraction (E1; 7.05–72.9%, averaging 39.4%). The carbonate (C2; 6.86–44.8%, 21.9%) and Fe/Mn oxides fraction (F3; 12.5–53.6%, 28.2%) were similar, while organic (O4; 0.62–25.0%, 7.91%) and residual fraction (R5; 0.22–8.54%, 2.62%) were the lowest. Significant correlation (R = 0.59–0.88) between the first two fractions (E1+C2) and bioaccessible Cd suggest they were the main sources of bioaccessible Cd in those contaminated soils.

Copper oxide nanoparticles (CuO NPs) in soil have received considerable attention because of their potential impact on the environment. In the present study, the stability of CuO NPs (50 nm and 80 nm) in eight soil solutions as well as the major influencing factors was investigated. The results showed that hetero-aggregation between natural colloids and NPs dominated the first stage of aggregation, afterwards the two different sized CuO NPs exhibited different aggregation behaviors. The aggregation of 80 nm CuO was inconspicuous except for notable aggregation observed in JX soil solution where the zeta potential of CuO NPs is close to zero. While for 50 nm CuO NPs, the aggregate size sharply decreased and the aggregates gradually reached a stable state. Further, the sedimentation rate and residual concentration of 50 nm CuO were found to be greater than those of 80 nm CuO. The residual amount of 80 nm CuO in the JX soil solution was lower than those in other soil solutions owing to the lowest zeta potential of the NPs. The pH of the soil solution has a significant effect on the stability of CuO NPs because of the shifting of the zeta potential of the NPs. In addition, dissolved organic carbon showed a statistically significant positive correlation with the residual concentration of CuO NPs. These findings imply the properties of CuO NPs as well as environmental factors including pH and DOC play key role in determining the fate, transport, and bioavailability of CuO NPs in soils.

Two commonly used dispersants, octyl phenol ethoxylate (Triton X-100) and sodium dodecyl sulfate (SDS), were employed to explore the effects of single or mixed surfactants on the dispersion, sedimentation and aggregation of multi-walled carbon nanotubes (MWCNTs). Non-ionic surfactant TX100 showed much superior capability to anionic surfactant SDS in dispersing MWCNTs due to the benzene ring structure in its tail group. The addition of SDS reduced the adsorption of TX100 on the surface of MWCNTs and the consequent suspension of MWCNTs. The dispersing ability of TX100–SDS binary mixture was between those of individual SDS and TX100. The introduction of SDS greatly retarded the sedimentation and aggregation of suspended MWCNTs. The critical coagulation concentration (CCC) values of suspended MWCNTs dispersed by TX100 (2000 mg l −1 ), SDS (2000 mg l −1 ) and TX100–SDS (2000 mg l −1 of each component) were 48.6, 398 and 324 mM, respectively, for Na + treatments. The CCC values were much lower for Ca 2+ treatments, which were 30.4 and 32.1 mM, respectively, for MWCNTs dispersed by TX100 and TX100–SDS mixture. Overall, these results demonstrated that although the introduction of SDS did not improve the ability of TX100 in suspending MWCNTs, the suspensions exhibited more stable properties than those dispersed by TX100 alone. Our findings have important implications for the design of surfactant mixtures and the prediction of the behaviour and fate of MWCNTs in the water environment.

Field experiments were conducted to explore the uptake and translocation of polycyclic aromatic hydrocarbons (PAHs) by wheat plants following sewage sludge application. Two types of application methods (single or annual application) and four application rates (5, 10, 20, and 40 t/ha/year) were investigated. The contents of 16 PAHs in soils, wheat roots and straws increased as the rate of sewage sludge application increased and were in the range of 20.7 to 241, 166 to 700, and 110 to 260 ng/g dry weight (dw), respectively. Meanwhile, for the PAH contents in grains (81.2–95.2 ng/g dw), no statistically significant differences were observed among different treatments. A single application of a large quantity of sewage sludge would likely increase the accumulation of PAHs in soil as well as their subsequent uptake and translocation by wheat. Profile analysis indicated that the transfer and accumulation of lower weight PAHs in wheat plants were greater. Regarding PAHs, sewage sludge application at 40 t/ha/year for 6 years did not significantly increase the risks of intake by wheat grain grown on sludge-amended soils.

Dissolved organic matters (DOMs) extracted from wheat straw (SDOM) and cow manure (MDOM) were used to investigate their effects on the suspension stability and aggregation of multi-walled carbon nanotubes (MWCNTs). Two types of DOM can effectively disperse and stabilize the MWCNTs. At initial MWCNT concentration of 500 mg/L, suspended MWCNT concentration ranged from 8.0 to 17.9 mg/L as DOM were varied from 50 to 200 mg/L dissolved organic carbon (DOC). The critical coagulation concentration (CCC) values were estimated to be 41.4 mM NaCl and 5.3 mM CaCl2 in the absence of DOM. The presence of SDOM and MDOM significantly retarded the aggregation rate of MWCNTs. The CCC values increased to 120 mM NaCl and 14.8 mM CaCl2 at SDOM concentration of 20 mg/L DOC. Due to its higher aromaticity and molecular weight, MDOM showed higher ability to stabilize MWCNTs, with CCC values of 201 mM and 15.8 mM at 20 mg/L DOC. These findings revealed that DOMs originated from agricultural wastes will have great impact on the dispersion and stabilization of MWCNTs, thus their fate in the aquatic environment.

There is increasing concern regarding soils contaminated with polycyclic aromatic hydrocarbons (PAHs). In the present study, the remediation of soil spiked with PAHs was explored by the combination of soil washing with sodium dodecyl sulfate (SDS) and subsequent oxidation through persulfate (PS) activated by Fe2+, nanoscale zero-valent iron (nZVI), and SiO2-coated nZVI (SiO2/nZVI). Results demonstrated that the removal of phenanthrene (PHE), fluoranthene (FLU), and pyrene (PYR) by SDS is an efficient means for soil decontamination. At SDS concentration of 20 g/L, the removal efficiencies of PHE, PYR, and FLU were 37%, 40%, and 44%, respectively. For the degradation of PAHs and SDS in the soil washing effluents, the efficiencies of PS activated with SiO2/nZVI were not significantly different from those of PS activated with nZVI and Fe2+ (p &gt, 0.05). In practice, SiO2/nZVI is more preferable due to the improved antioxidation and dispersibility. At the dosage of 2 g/L (in the amount of iron) of SiO2/nZVI, the removal efficiencies of PHE, FLU, PYR, and SDS within 30 min of treatment were 75%, 85%, 87%, and 34%, respectively. The degradation of SDS was much lower than those of PAHs, which facilitated the recycle of SDS. Our findings suggest that PS activated with SiO2/nZVI is a promising method for the treatment of soil washing effluents containing SDS and PAHs.

Dissolved organic matter (DOM) extracted from wheat straw (SDOM) and cow manure (MDOM) were used to investigate their effects on the solubilization, uptake, and translocation of 2,2′,4,4′-tetrabromodiphenyl ether (BDE-47). Partition coefficients (KDOC) of BDE 47 between water and the two types of DOM were measured by the solubility enhancement method. The uptake and translocation of BDE 47 by wheat plants were explored by hydroponic exposure experiments. In the range of 0 to 100 mg/L of DOM, the solubility of BDE 47 increased with increasing concentrations of DOM. The log [KDOC] values of BDE 47 in SDOM and MDOM solutions were 5.77 and 5.31, respectively. The log [KDOC] values of BDE 47 in SDOM solutions were higher than those in MDOM solutions, which might be ascribed to the higher content of aliphatic carbon and lower molecular weight of SDOM. The addition of DOM (50 mg/L) significantly increased the accumulation of BDE 47 in the shoots of wheat plants. Wheat straw DOM had greater effect than MDOM in enhancing the accumulation of BDE 47. This study demonstrated the potential risk of BDE 47 to plants resulting from DOM-facilitated transport or the changes in metabolic properties.

Although the agricultural use of dichlorodiphenyltrichloroethane (DDT) has been banned for decades in many countries around the world, the detection of DDT and its metabolites in soils is very common due to their persistence. DDTs (sum of DDT and its metabolites) in farmland soils can be absorbed by crops at different levels and accumulate in the edible parts of agricultural products, posing threats to the health of human being. However, no information on the species sensitivity distribution (SSD) of crops with regard to DDTs has been reported due to the lack of enough bioavailability data and models to normalize the bioavailability data from different sources. Based on the bioconcentration factors of 17 crop species in Chinese soils obtained from previous studies, the criteria of DDTs in soils was derived according to the quality standard of agricultural products using the SSD method. Corrections for water content and aging time were conducted to normalize the data from different sources. The risk values of agricultural products at different concentration levels of DDTs in soils were also evaluated. It was found that oil crops are able to take up more DDTs than non-oil crops, so the soil criteria were calculated separately for oil crops and non-oil crops, which were 0.083 mg/kg and 0.29 mg/kg, respectively. With the residual concentrations of DDTs in soils at the range of 0.01–0.5 mg/kg, 0–8% of the agricultural products exceeded the permissible limits for DDTs which were set in the National Food Safety Standard of China. The results also demonstrated the feasibility for applying SSDs to derive the soil criteria of DDTs in order to ensure the safety of agricultural products. This work will provide information for the risk assessment and the establishment of soil environmental quality standards to ensure safe agricultural production.

The adsorption of sulfamethazine (SMZ) by pristine and hydroxylated multi-walled carbon nanotubes (P-MWCNTs, H-MWCNTs) was studied under varied pH, ionic strength, cations and anions in solution. The results suggest that the SMZ adsorption onto MWCNTs can be depicted well by the pseudo-second-order and Langmuir models. The adsorption of SMZ onto MWCNTs was ionic strength and pH dependent, which indicated hydrophobic and electrostatic interactions, may be the main adsorption mechanisms. The presence of cations at 0.5 mM showed different effects on SMZ adsorption. Cu2+ slightly decreased SMZ adsorption by 10% to 20% at solution pH of 2.3 and 4.9, due to the competing effect of Cu2+ with SMZ+ and SMZ±. But Cu2+ increased SMZ− adsorption by 20% to 60% at solution pH of 7.4 and 10.0, due to the facilitating effect of the complex formation of Cu2+–SMZ. Al3+ promoted the SMZ adsorption onto P-MWCNTs, which can be attributed to the facilitating effect of Al3+ through a metal bridge, while inhibiting the SMZ adsorption by H-MWCNTs, which can be ascribed to the competing effect between Al3+ and SMZ for the negatively charged functional groups and the shielding effect of adsorbed Al3+ with a larger hydration radius at pH of 2.3, 4.9 and 7.4. SMZ adsorption was slightly decreased with the addition of 0.5 mM anions (Cl−, CO32−, SO42−, PO43−) due to the increase in density of negative charge on the MWCNTs' surface. The μ-FTIR results showed that π–π interaction may also play an important role in the adsorption process.

Triton X-100 (TX100) and Brij 35 (B35) were used to investigate the elevated critical micelle concentration (CMC) induced by surfactant sorption and its influence on PAH removal in soil washing systems. The surface tension technique was applied to determine the CMC and the apparent CMC (CMCsoil) in soil–water systems. Surfactant sorption experiments were conducted by the batch equilibration technique. Surfactants sorbed on the soil at concentrations below the CMCsoil were quantified with data from the surface tension experiments for both an aqueous system and a soil–water system. Due to sorption, the CMCsoil values of the two surfactants are 2.75 and 6.31 times their corresponding CMC values in aqueous solutions, respectively. At concentrations below CMCsoil, the loss of B35 (92–99.7 %) was greater than that of TX100 (63–92 %). The PAH removal efficiencies are greatly dependent on the CMCsoil value. At surfactant concentrations below CMCsoil, the PAH removal is very low and remains almost invariable. Whereas, at concentrations above CMCsoil, the PAH removal increases greatly. B35 inhibited PAH desorption at concentrations below its CMCsoil. For TX100, some degree of PAH desorption enhancement was observed at concentrations below its CMCsoil. CMCsoil is a key parameter while selecting a surfactant for a specific soil washing system, only surfactant concentrations above their CMCsoil should be evaluated.

Glass-etched micromodel and visualization technology were used to research the removal mechanisms of residual light non-aqueous phase liquids (LNAPLs) droplets at pore scale. In this research, n-hexadecane was selected as the LNAPL model substance. During the injection of de-ionized water into the pore channel, residual n-hexadecane droplet was removed quickly at first, then gradually became slow and finally remained nearly invariable; the droplet size after a definite time depends on its initial value. The relationship between total volume of residual n-hexadecane and time can be described by a logarithmic equation: V = V 0 − 0.0152lnt + 0.0360 (0

The concentrations of 16 polycyclic aromatic hydrocarbons (PAHs) in US EPA priority list were analyzed in the bulk and six particle size fractions of soil samples from a coke oven plant. The relationships of PAHs concentrations with total organic carbon (TOC), black carbon (BC) and other forms of organic carbon (OC) contents have been investigated. Total PAH concentrations ranged from 6.27 to 40.18 mg kg(-1) dry weight. The highest total PAH concentration occurred in the 250-500 microm size fraction. The maximum individual PAH concentration was in the 250-500 microm or 500-2000 microm size fraction. The size fractions of 125-500 microm and50 microm have higher percentages and contributed 24.62% and 23.33% of the total PAH mass, respectively. The relative abundance of individual PAH compounds and PAH molecular indices present typical characteristic pyrogenic origin. The maximal TOC and BC contents were found in the 125-250 microm size fraction. Strong positive linear relationship between total PAH concentration and TOC or BC has been demonstrated, with a linear regression coefficient value of 0.7277 and 0.9245, respectively. The linear relationship between total PAH concentration versus OC (OC = TOC - BC) is weaker than that versus TOC or BC, with a correlation coefficient of 0.4117. It indicates that partitioned in organic matter, especially in black carbon is the dominant form of PAHs in the soil.

The effects of agricultural wastes on degradation of polycyclic aromatic hydrocarbons(PAHs) and abundance of ammonia-oxidizing archaea (AOA) and ammonia-oxidizing bacteria (AOB) in PAH-polluted soils were determined by liquid chromatography and real-time quantitative PCR. The results showed that addition of agricultural wastes didn't improve the degradation of PAHs, in the contrary, the degradation of PAHs decreased in the soil added with wheat straw. And the degradation rate of PAHs decreased with increased molecular weight of PAHs. Furthermore, the abundance of AOA and AOB was enhanced in PAH-polluted soils after adding agricultural wastes, the content of pyrene and benzo(a)pyrene has significant negative correlation with the abundance of AOA. These results suggested that the degradation of PAHs can not be promoted through applying agricultural wastes into the soils freshly polluted by PAHs. Pyrene and benzo(a)pyrene would reduce the abundance of AOA, while addition of agricultural wastes could improve the ammonia oxidation function in PAH-polluted soils. This study provided some insights for the remediation and risk assessment of PAH-polluted soils.

Field experiments were conducted to explore the effects of different sewage sludge amendment strategies on the accumulation and translocation of polybrominated diphenyl ethers (PBDEs) in soil-wheat systems. Two types of application methods (single or annual application) and four annual application rates (5, 10, 20, and 40 t ha(-1) year(-1)) were investigated. BDE 209 was detected in all of the sewage sludge amended soils and different parts of wheat plants collected from the contaminated soils. However, the other seven PBDE congeners (BDE 28, BDE 47, BDE 99, BDE 100, BDE 153, BDE 154, and BDE 183) were not detected or were only observed at very low levels. A single application of sewage sludge in large quantities would likely increase accumulation of BDE 209 in soil and its subsequent uptake and translocation by wheat. The concentrations of BDE 209 in soils, wheat roots and straws increased with the increasing sewage sludge application rate. There is a negative correlation between the root accumulation factors (the ratios of concentrations in wheat roots to those in soils) and soil total organic carbon (R(2)=0.84,P0.05), demonstrating that the bioavailability of BDE 209 was controlled by the soil total organic carbon. BDE 209 concentrations in the grains from the sewage sludge amended soils were not significantly different from those of the control soils, suggesting that atmospheric deposition was the main source of BDE 209 detected in the grains.

Wheat straw biochars produced at 400, 600 and 800°C (BC400, BC600 and BC800) were used to selectively adsorb PAHs from soil washing effluents. For soil washing effluents contained Phenanthrene (PHE), Fluoranthene (FLU), Pyrene (PYR) and Triton X-100 (TX100), biochars at 2 (for BC800) or 6 g L(-1) (for BC400 and BC600) can remove 71.8-98.6% of PAHs while recover more than 87% of TX100. PAH removals increase with increasing biochar dose. However, excess biochar is detrimental to the recovery of surfactant. For a specific biochar dose, PAH removal and TX100 loss increase with increasing pyrolytic temperature. For BC400 and BC600, PAH removal follows the order of PHE>FLU>PYR, while the order is reversed with PYR>FLU>PHE for BC800. Biochars have much higher sorption affinity for PAHs than for TX100. It is therefore suggested that biochar is a good alternative for selective adsorption of PAHs and recovery of TX100 in soil washing process.

Ammonium perfluorooctanoate (APFO) is an emerging environmental pollutant attracting significant attention due to its global distribution, high persistence, and bioaccumulation properties. The decomposition of APFO in aqueous solution with a combination of persulfate oxidant and ultrasonic irradiation was investigated. The effects of operating parameters, such as ultrasonic power, persulfate concentration, APFO concentration, and initial media pH on APFO degradation were discussed. In the absence of persulfate, 35.5% of initial APFO in 46.4 μmol/L solution under ultrasound irradiation, was decomposed rapidly after 120 min with the defluorination ratio reaching 6.73%. In contrast, when 10 mmol/L persulfate was used, 51.2% of initial APFO (46.4 μmol/L) was decomposed and the defluorination ratio reached 11.15% within 120 min reaction time. Enhancement of the decomposition of APFO can be explained by acceleration of substrate decarboxylation, induced by sulfate radical anions formed from the persulfate during ultrasonic irradiation. The SO4(-•)/APFO reactions at the bubble-water interface appear to be the primary pathway for the sonochemical degradation of the perfluorinated surfactants.

Biodiesel production from soybean oil with methanol was performed in the presence of a Bronsted acidic ionic liquid-based catalyst under ultrasound irradiation. The influences of various parameters on the transesterification reaction, including the amount of catalyst, the molar ratio of methanol to oil, the temperature and the ultrasound power, were investigated. The optimal conditions were: methanol/oil molar ratio of 9:1, 1.0 wt.% catalyst in oil, ultrasound power of 200 W, and reaction temperature of 60 °C. Under these conditions, the conversion of triglycerides to fatty acid methyl esters was about 93.2% within the reaction time of 60 min.

To investigate the protective effects of vitamin B(12), ginseng saponin, and folic acid on mouse embryos subjected to high heat.Mice were used for the experiment.After exposure of pregnant mice to high heat, the rates of teratism, stillbirth, and fetal absorption were markedly lower in mice treated with ginseng saponin and folic acid following heat exposure than in untreated mice. There were no significant differences in these rates when comparing mice treated with vitamin B(12) with the untreated mice.Ginseng saponin and folic acid can lessen injuries to murine embryos caused by high heat, while vitamin B(12) has little protective effect against high temperature except for promoting overall embryonic growth.

To study the effect of zinc L-lysine and taurine against teratogenesis caused by hyperthermia in pregnant mice.Eighty seven female Swiss mice with the gestational age of 8 days were exposed to 42.5 approximately 43.0 degrees C waterbath for 9 minutes. Six hours later the same procedure was repeated for 8 minutes. On the 9th gestational day zinc L-lysine (200 mg/kg) was perfused orally into 30 pregnant mice, and taurine (300 mg/kg) was perfused orally into 27 pregnant mice. The other 30 mice were used as controls. On the 18th gestational day, the pregnant mice were all killed. The teratogenic rate, embryo rate, and absorbed embryo rate, body weight, body length, and tail length of each mouse were examined.The teratogenic rates in zinc L-lysine group and taurine group were 1.1% and 1.2% respectively, both significantly lower than that in the control group (5.4%, P0.01). The dead embryo rates in the zinc L-lysine group and taurine group were 1.0% and 1.5% respectively, both significantly lower than that in the control group (3.5%, P0.01). The absorbed embryo rates in the zinc L-lysine group and taurine group were both 5.6%, significantly lower than that in the control group (14.3%, P0.01). The mean weight of the first two groups was 1 370 mg +/- 180 mg and 1 380 mg +/- 190 mg respectively, significantly greater than that in the control group (1 280 mg +/- 240 mg, P0.01). The mean body length in the first two groups was 28.1 mm +/- 1.9 mm and 28.0 mm +/- 2.1 mm respectively, significantly greater than that in the control group (26.7 mm +/- 2.2 mm, P0.01). The mean tail length in the first two groups was 12.2 mm +/- 1.3 mm and 12.2 mm +/- 1.9 mm respectively, significantly greater than that in the control group (11.6 mm +/- 1.5 mm, P0.01).Zinc L-lysine and taurine have a significant effect against teratogenesis caused by hyperthermia and promote the embryo growth.