[Objectives]This study was conducted to determine the contents of such five heavy metals as lead(Pb),cadmium(Cd),arsenic(As),mercury(Hg)and copper(Cu)and the contents of nine kinds of organochlorine pesticide residues...[Objectives]This study was conducted to determine the contents of such five heavy metals as lead(Pb),cadmium(Cd),arsenic(As),mercury(Hg)and copper(Cu)and the contents of nine kinds of organochlorine pesticide residues including total BHC(α-BHC,β-BHC,γ-BHC,δ-BHC)and total DDT(pp-DDE,pp-DDD,op-DDT,pp-DDT)and pentachloronitrobenzene in the Zhuang medicine Herba Polygoni Chinensis from 13 producing areas.[Methods]The five heavy metals were determined in accordance with the second method of general rule 2341,the inductively coupled plasma mass spectrometry method,in part 4 of the 2020 edition of Chinese Pharmacopoeia;and the nine organochlorines were determined in accordance with the first method of general rule 2341,organochlorine pesticide residue determination method(chromatography),in part 4 of the 2020 edition of Chinese Pharmacopoeia.[Results]In the Herba Polygoni Chinensis from 13 origins,the lead contents were in the range of 0.50-3.28 mg/kg;the cadmium contents were in the range of 0.06-4.21 mg/kg;the arsenic contents were in the range of 0.16-6.9 mg/kg;the copper contents were in the range of 10.5-45.1 mg/kg;the mercury contents were in the range of 0.00-0.003 mg/kg;and the nine organochlorines including the total benzene hexachloride(α-BHC,β-BHC,γ-BHC,δ-BHC),total DDT(pp-DDE,pp-DDD,op-DDT,pp-DDT)and pentachloronitrobenzene were all not detected.Referring to part 4 of the 2020 edition of Chinese Pharmacopoeia,the Cu and As of the Herba Polygoni Chinensis produced in Hezhou exceeded the standards,the Cu of the Herba Polygoni Chinensis produced in Wuzhou exceeded the standard,and the As of the Herba Polygoni Chinensis produced in Yulin City and Guilin City exceeded the standard.[Conclusions]This study provides safety limit test data for the development and utilization of Herba Polygoni Chinensis of the Zhuang medicine.展开更多
[Objectives]To establish a method for the determination of heavy metals and pesticide residues in Dendrobium officinale produced in Guangxi and its culture substrate.[Methods]The contents of five heavy metals(Pb,Cd,As...[Objectives]To establish a method for the determination of heavy metals and pesticide residues in Dendrobium officinale produced in Guangxi and its culture substrate.[Methods]The contents of five heavy metals(Pb,Cd,As,Hg and Cu)were determined by the atomic absorption spectrophotometric(AAS)method;residues of 9 organochlorine pesticides(α-BHC,β-BHC,γ-BHC,δ-BHC,p,p′-DDT,p,p′-DDE,p,p′-DDD,o,p′-DDT and pentachloronitrobenzene)were determined by gas chromatography(GC).[Results]The contents of five heavy metals in the medicinal materials of D.officinale produced in Guangxi were 0.96,0.21,0.021 mg/kg,and not detected,and 0.35 mg/kg.The contents of five heavy metals in the culture substrate were 0.03,0.19,0.21,0.004 and 1.80 mg/kg,respectively;the content of 9 organochlorine pesticide residues in the sample was not detected.[Conclusions]The detection results of heavy metal content and organochlorine pesticide residues in D.officinale produced in Guangxi and its substrate are consistent with the limit requirements of the Chinese Pharmacopoeia.This experiment is expected to provide reliable data reference for ensuring the safety of the drug resources of D.officinale in Guangxi.展开更多
This study assessed sediment contamination by heavy metals and pesticide active ingredients linked to chemical inputs used in agricultural activities in the lower Ouémé. Pesticide residues from the organochl...This study assessed sediment contamination by heavy metals and pesticide active ingredients linked to chemical inputs used in agricultural activities in the lower Ouémé. Pesticide residues from the organochlorine, pyrethroid and organophosphorus families were investigated by gas chromatography, and heavy metals (Cd, Pb, As, Ni, Zn, Fe, Mg, Cr and Hg) by atomic absorption spectrophotometry. The metallic pollution indices, the contamination factor (CF) and the ecological risk index were calculated. The results revealed 8 active ingredients in the rainy season and 9 in the dry season. Glyphosate was the active ingredient with the highest concentration at all stations, 9.65 ± 0.84 mg/kg recorded in the dry season at the Aguigadji station. All glyphosate values were above the EQS. DDT, Atrazine and Endosulfan also showed high concentrations in the dry and rainy seasons. Emamectin, Abamectin and Lambda Cyhalothrin also showed high concentrations in the dry season at Aguigadji, Ahlan and Sele. Only glyphosate was recorded at the control station (Toho), but in very low concentrations. Lead showed the highest concentrations at all the stations, 265.96 ± 21.02 mg/Kg in the rainy season and 255.38 ± 79.09 mg/Kg in the dry season, all detected at the Aguigadji station and above the EQS. Zn, Ni, Fe, Cu and Cr were all representative in both the dry and rainy seasons at the contaminated stations. Manganese showed high concentrations in the rainy season. Pb showed very high contamination (FC ≥ 6) at the Aguigadji and Ahlan stations and significant contamination (3 ≤ FC 6) at the Sele station in both the rainy and dry seasons. Ni, Hg and Cd, showed either moderate or significant contamination at the contaminated stations. The risk values showed a considerable ecological Ri (190 ≤ Ri < 380) in the rainy season and a moderate ecological Ri (95 ≤ Ri < 190) in the dry season at these contaminated stations.展开更多
Objective: The main objective of this study was to assess the degree of contamination of surface waters by heavy metals and pesticides. Method: To this end, data were collected in December 2022 from four specific samp...Objective: The main objective of this study was to assess the degree of contamination of surface waters by heavy metals and pesticides. Method: To this end, data were collected in December 2022 from four specific sampling stations: Okpara, Térou, Affon and Adjiro. Levels of heavy metals, including cadmium, chromium, copper, iron, mercury, nickel and lead, were measured and subjected to in-depth statistical analysis using graphical summation models. In addition, the concentrations of pesticide active ingredients present in the samples were interpreted and evaluated. The statistical data collected during this study were processed using R software, version 3.5.0. Results: The values obtained at the different stations Okpara, Térou, Affon and Adjiro are respectively Arsenic (2 × 10<sup>-4</sup> mg/L;2.2 × 10<sup>-1</sup> mg/L;1.2 × 10<sup>-4</sup> mg/L;2 × 10<sup>-4</sup> mg/L), Cadmium (4.4 × 10<sup>-5</sup> mg/L;1.1 × 10<sup>-2</sup> mg/L;10<sup>-4</sup> mg/L;4 × 10<sup>-4</sup> mg/L). Then Copper (7 × 10<sup>-4</sup> mg/L;3 × 10<sup>-3</sup> mg/L;7 × 10<sup>-4</sup> mg/L;1 × 10<sup>-4</sup> mg/L), Iron (1.51 mg/L;6.4 × 10<sup>-1</sup> mg/L;2.0012 mg/L;2.9 × 10<sup>-1</sup> mg/L), Lead (0 mg/L;0 mg/L;1.5 × 10<sup>-3</sup> mg/L;1.5 × 10<sup>-3</sup> mg/L). Mercury, nickel and chromium were not detected in surface waters. It is important to note that the values obtained for trace metals (Cadmium, Chromium, Copper, Iron, Mercury, nickel and chromium were not detected in surface waters. It is important to note that the values obtained for trace metals (cadmium, chromium, copper, iron, mercury, nickel and lead) were all below the guideline standards set by the WHO in 2006 for uncontaminated surface waters. This indicates that the surface waters of the Upper Ouémé were below acceptable contamination thresholds in terms of heavy metals. However, the presence of pesticide active ingredients such as cyfluthrin, endosulfan-alpha, endosulfan-beta, profenosfos, tihan, atrazine, gala super and glycel clearly indicates that these surface waters are subject to agricultural contamination.展开更多
The toxicity of heavy metals (Hg2 + , Zn2 + ) and pesticides has been investigated by comparing the physiological properties in wild and tolerant strains of Synechococcus cedrorum 1191. The differential pattern of gro...The toxicity of heavy metals (Hg2 + , Zn2 + ) and pesticides has been investigated by comparing the physiological properties in wild and tolerant strains of Synechococcus cedrorum 1191. The differential pattern of growth, absorption spectra of pigments and nutrient uptake was observed in tolerant strain.展开更多
Four different methods,namely mineralogical analysis,three-stage BCR sequential extraction procedure,dynamic leaching test and Hakanson Potential Ecological Risk Index Method were used to access the environmental acti...Four different methods,namely mineralogical analysis,three-stage BCR sequential extraction procedure,dynamic leaching test and Hakanson Potential Ecological Risk Index Method were used to access the environmental activity and potential ecological risks of heavy metals in zinc leaching residue.The results demonstrate that the environmental activity of heavy metals declines in the following order：CdZnCuAsPb.Potential ecological risk indices for single heavy metal are CdZnCuAsPb.Cd has serious potential ecological risk to the ecological environment and contributes most to the potential toxicity response indices for various heavy metals in the residue.展开更多
Taking three mains edibles products(walnut, prickly ash and bamboo shoots) and origin soil in central area of Sichuan Province as the study objects, this research aimed at revealing the level of heavy metals and pesti...Taking three mains edibles products(walnut, prickly ash and bamboo shoots) and origin soil in central area of Sichuan Province as the study objects, this research aimed at revealing the level of heavy metals and pesticide residue and comprehensive evaluation the soil heavy metal pollution in the region. The results showed that: ① Soil organic matter, total nitrogen, total phosphorus and heavy metal contents of mercury, arsenic in the south area were significant higher than that in the north area, while the heavy metal contents of lead and copper were significantly higher in the north area; ② The pollution index of six heavy metals of cadmium, mercury, arsenic, lead, chromium and copper in the producing area was less than 1.0. However, the integrated pollution index was at a warning level, and there was a potential risk of cadmium contamination; ③ The walnut samples exceeded the lead limit value over 75% in the north area and over 35% in the south area, and the same as 30% of bamboo shoot samples; ④ There was a significant negative correlation of mercury content between walnut samples and production soil, and a significant positive correlation of arsenic content between bamboo shoots and production soil. In addition, there is no significant correlation of heavy metal contents between prickly samples and production soil; ⑤ Fenthion residues were detected in walnuts, malathion samples were detected in prickly ash, and chlorothalonil, dimethoate and chlorpyrifos residues in bamboo shoots samples. None of theses pesticide residues exceeded the standard limit value. In general, the soil is in well sanitary condition and the edible forest products are not exposed to the contamination of pesticide residues in the study area. The quality and safety of the prickly ash is good while the walnut and bamboo shoots have certain risks in terms of high lead level.展开更多
The levels of common pesticides and heavy metals in Dendrobium officinale grown from 2012 to 2014 were measured, and three planting methods were used in 2014. The quality of plant husbandry improved during the study p...The levels of common pesticides and heavy metals in Dendrobium officinale grown from 2012 to 2014 were measured, and three planting methods were used in 2014. The quality of plant husbandry improved during the study period. Thirteen types of pesticides were detected in D. officinale grown in 2014 and antimicrobials, including carbendazim, difenoconazole and azoxystrobin, were evident in 61.53% of plants. These three pesticides constituted 72.33% of all the antimicrobials detected. Planting methods affected the levels of pesticides and heavy metals. Trellising in plastic sheds was optimal, being associated with the lowest amounts of both pesticides and heavy metals. Both cadmium（Cd） and lead（Pb） levels were high in treed plants, whereas Cr, As and Cu levels were the highest in potted plants.展开更多
Urban soil is the main component of urban ecological systems and the key risk receptor from urbanization. Heavy metal and green pesticide pollutions in urban soils have been widely reported with the expanding of urban...Urban soil is the main component of urban ecological systems and the key risk receptor from urbanization. Heavy metal and green pesticide pollutions in urban soils have been widely reported with the expanding of urbanization. Since urban soil pollution comes from various resources, application of integrated thinking and methods is needed in ecological risk assessment of urban soil pollution. This paper synthetically reviewed the combined pollution of heavy metals and pesticide, and ecological risk assessment, and then proposed some research trends and areas in the future that are required to carry out intensively according to the present situation of environmental pollution and international research fronts.展开更多
Low temperature plasma was used to treat sludge,and the effects of discharge time on the content of different forms of heavy metals in the sludge were studied. The results showed that Cu and Zn content in the domestic...Low temperature plasma was used to treat sludge,and the effects of discharge time on the content of different forms of heavy metals in the sludge were studied. The results showed that Cu and Zn content in the domestic sludge could basically meet the requirements of GB 4284-2018,GB/T 23486-2009,CJ/T 362-2011 and CJ/T 309-2009. There were big differences between different forms of the heavy metals. According to the proportions of different forms of Cu in the sludge,different forms of Cu are arranged as follows: organic state > carbonate bound state> residual state > exchangeable state > iron-manganese oxidation state,and Cu mainly existed in an organic state. Various forms of Zn are arranged in order of the proportion as follows: iron-manganese oxidation state > residual state > carbonate bound state > exchangeable state > organic state,and Zn mainly existed in an iron-manganese oxidation state. After the treatment of sludge by low temperature plasma,the content of exchangeable Cu and Zn in the sludge increased,while the content and proportion of residual Cu and Zn all reduced.展开更多
Fishponds waters intended to satisfy the nutritional needs of the populations in terms of supply of fish resources are strongly and unfortunately exposed to the mobility and dispersion of metallic trace elements (TMEs...Fishponds waters intended to satisfy the nutritional needs of the populations in terms of supply of fish resources are strongly and unfortunately exposed to the mobility and dispersion of metallic trace elements (TMEs) or to the persistence in the environment and in the form of pesticide residues from human activities. The objective of this work is to evaluate, on the one hand, the levels of identified pesticide residues and, on the other hand, those of researched TMEs (lead, cadmium, mercury and arsenic) in the waters of ponds used for fish farming in Zépréguhé, a locality located 9 km from the town of Daloa in the centre-west of Côte d’Ivoire. The dosage of the samples carried out by means of a gas chromatograph coupled to a mass spectrometer (GC/MS) made it possible to detect nine (9) pesticide molecules, including eight (8) organochlorines and a single molecule from the pyrethroid family, obtained from the detection limit of 0.006 μg/L and the quantification limit of 0.018 μg/L. The maximum average concentration was obtained with α-endosulfan for a content reaching 0.8038 μg/L and well above the maximum admissible concentration of 0.1 μg/L. The TMEs were quantified using an atomic absorption spectrophotometer (AAS). Arsenic is the most abundant metal with an average concentration of 9.497 μg/L. With the exception of lead, these measured levels are above the acceptable limit values for freshwater. This study showed that human activities such as the use of fertilisers and plant protection products in plantations, sand extraction and road traffic have a negative impact on the quality of the water in ponds used for fish breeding.展开更多
This study investigates the concentrations of metals in leafy vegetables in Bethlehem and Jenin districts in Palestine. The concentrations of Fe, Pb, Cr, Co, Cu, Mn, Cd, and Zn were measured. Vegetables including spin...This study investigates the concentrations of metals in leafy vegetables in Bethlehem and Jenin districts in Palestine. The concentrations of Fe, Pb, Cr, Co, Cu, Mn, Cd, and Zn were measured. Vegetables including spinach, arugula, and parsley were collected from different farms from both regions, and analyzed by using ICP-MS. In Bethlehem region, Iron concentrations were ranged from 25 to 1046 mg/kg. Iron concentrations were higher than the WHO/FAO limits of 425 mg/kg in 33% of the samples. Lead concentrations were ranged from 0.04 to 1.77 mg/kg. Lead concentrations were higher than the WHO/FAO limits of 0.3 mg/kg in 40% of the samples. Chromium concentrations were ranged from 0.02 to 2.51 mg/kg. Chromium concentrations were higher than the WHO/FAO limits of 1.3 mg/kg in 13% of the samples. Zinc concentrations were ranged from 4 to 107 mg/kg. Zinc concentrations were higher than the WHO/FAO limits of 99.4 mg/kg in 6.6% of the samples. Cadmium concentrations were ranged from 0.01 to 1.4 mg/kg. Cadmium concentrations were higher than the WHO/FAO limits of 0.2 mg/kg in 13% of the samples. The concentration of Manganese, Cobalt and Cupper were all below the WHO/FAO limits of 500, 50 and 73 mg/kg respectively. In Jenin region, Iron concentrations were ranged from 42 to 543 mg/kg. Iron concentrations were higher than the WHO/FAO limits of 425 mg/kg in 20% of the samples. Lead concentrations were ranged from 0.05 to 0.67 mg/kg. Lead concentrations were higher than the WHO/FAO limits of 0.3 mg/kg in 20% of the samples. Copper concentrations were ranged from 0.62 to 278 mg/kg. Copper concentrations were higher than the WHO/FAO limits of 73 mg/kg in 6.66% of the samples. Cadmium concentrations were ranged from 0.02 to 1.62 mg/kg. Cadmium concentrations were higher than the WHO/FAO limits of 0.2 mg/kg in 6.66% of the samples. The concentration of Chromium, Manganese, Cobalt and Cupper were all below the WHO/FAO limits. It was concluded that the contamination found in some leafy vegetable samples was not related to either irrigation water or soil. It was attributed to the misuse of pesticides.展开更多
In Kazakhstan, camel breeding mainly occupies areas sometimes close to polluting industries or other sources of pollu- tion as industrial agriculture, mainly cotton. Products issued from camel farms close to these sou...In Kazakhstan, camel breeding mainly occupies areas sometimes close to polluting industries or other sources of pollu- tion as industrial agriculture, mainly cotton. Products issued from camel farms close to these sources as camel raw milk and fermented milk (shubat), wool and meat, traditionally used by humans could be contaminated. We investigated camel raw milk and fermented milk for the content of heavy metals (lead, cadmium, zinc and copper), radionuclide and some organic pollutants (PAHs, pesticides and indicator PCBs) in samples from different regions with a priori high risk of pollution (Atyrau, Kyzylorda, South-Kazakhstan and Almaty region). In the present paper, only some milk samples presented high lead concentration (> 500 ppb). After analysis for organic pollutants, it was observed some traces of hexachlorocyclohexane, lindane, hexanchlorothalonil in milk samples from different regions. One sample was also slightly contaminated with radionuclide. These preliminary results allow establishing a first map of risk for camel farming. As the whole, South-Kazakhstan appeared the most exposed region.展开更多
In order to assess the contamination of edible marine organisms in Quanzhou and Xinghua Bays, Fujian Province, China, concentrations of organochlorine pesticides （hexachlorocyclohexane isomers or HCHs and dichlorodip...In order to assess the contamination of edible marine organisms in Quanzhou and Xinghua Bays, Fujian Province, China, concentrations of organochlorine pesticides （hexachlorocyclohexane isomers or HCHs and dichlorodiphenyltrichloroethane isomers/derivatives or DDTs） and heavy metals （Cu, Pb, Zn, As, Cr, Cd, Ni and Hg） in 13 species collected from different sites in the hays were analyzed by GC-ECD and ICP-MS. The concentration of the sum of DDTs exceeded that the sum of HCHs in the samples. Most of the organisms showed higher levels of DDTs than the first level criterion （10 ng/g） for marine biological quality in China （GB 18421-2001） but conformed to the first level criterion （20 ng/g） for HCHs. The estimated mean daily uptake of pesticides was below the level for minimal risk to the consumers. The levels of Cd, As and Pb in most organisms from both bays were markedly elevated and above the recommended legal limits for human consumption. Our results showed the need for routine monitoring of marine species contamination to ensure public and environmental health.展开更多
The presence of high levels of heavy metals in anaerobic fermentation residues is a major obstacle to the resource utilization and urgent research for removal of heavy metals in the biogas slurry is needed.The handlin...The presence of high levels of heavy metals in anaerobic fermentation residues is a major obstacle to the resource utilization and urgent research for removal of heavy metals in the biogas slurry is needed.The handling of large-scale residue slurry and safely returning to field urgently needed constructive suggestion.The contents of heavy metal elements in the residue of anaerobic digestion processes of the wastewater and waste of the piggery were mainly investigated.The contents of heavy metals in the original fluid and the centrifugal solution were determined in this study.They included elements,such as Cu,Zn,Cr,Cd,Pb,As,Ni,Mn,and Se,which were compared with the existing standard including the irrigation water quality standards(GB5084-2005),comprehensive discharge standard of sewage(GB8978-1996)and water-solubility humic acid fertilizer quality standards(NY1106-2010).The preliminary data suggested that both the heavy metals before and after centrifugation were in excess of the standards to some degree and the exceeding standard rate declined significantly after centrifugation.The absolute contents of heavy metals after centrifugation declined significantly compared with that before centrifugation.Those ratios are 91.8%,73.2%,47.6%,94.5%,93.5%,59.4%,95.8%,100%for Zn,As,Cd,Cr,Cu,Ni,Mn,Pb,respectively.A descriptive statistics as well as a correlational analysis showed that there existed strong correlation among Cu,Pb,and the total suspended solids(TS).Meanwhile,significant correlation was found among TS,Cd,Zn,As,Cr,Ni,and Mn at 0.01 level.The data and the analysis above provided the theoretical and experimental support for the removal of heavy mental mainly characterized by the removal of TS.According to the comparison between contents of heavy mental conversed from large amount nutrients and corresponding standard(NY1110-2006),only as was found beyond standard.It was feasible to apply biogas residues after centrifugation as water-solubility fertilizer due to the fact that As had low accumulation efficiency in soil and plants.展开更多
Concentrations of polybrominated diphenyl ethers (PBDEs), organochlorine pesticides (OCPs) and heavy metals in two sediment cores, taken from the Dagu Drainage River, were determined. The contamination trends of these...Concentrations of polybrominated diphenyl ethers (PBDEs), organochlorine pesticides (OCPs) and heavy metals in two sediment cores, taken from the Dagu Drainage River, were determined. The contamination trends of these three kinds of compounds were obtained. The results showed that concentrations of PBDEs increased in recent years; there were new contamination sources for OCPs in this area; contamination levels of heavy metals had no significant change in the last several years. Comparing the results of these two cores, erosion and dilution of seawater had different effects on the transportation of these compounds.展开更多
The mechanisms of adsorption of pesticides（dimethoate, metalaxyl, atrazine, malathion and prometryn） and heavy metals（Cu, Cd, Pb, Zn and Ni） coexisting in sediments, with pesticides as target pollutants, and the i...The mechanisms of adsorption of pesticides（dimethoate, metalaxyl, atrazine, malathion and prometryn） and heavy metals（Cu, Cd, Pb, Zn and Ni） coexisting in sediments, with pesticides as target pollutants, and the influence of their main effects and double-order interaction effects were studied using the experimental design module in the Minitab software package with a 2^10-3 fractional factorial design method at resolution V. The main, double-order interaction, synergistic and antagonistic effect values of pollutant concentrations influencing the adsorption of pesticides were set as dependent variables, while various quantum chemical parameters of pesticides were set as independent variables, and two-dimensional quantitative structure activity relationship（2D-QSAR） models were established by stepwise regression to reveal the adsorption mechanisms of pesticides in a composite contamination system. The main effects of pollutants concentration played the primary role in the adsorption of dimethoate and malathion（the rates of contributions were 53.54% and 56.46%, respectively）, while double-order interaction effects were primarily responsible for metalaxyl, atrazine and prometryn adsorption（the rates of contributions were 79.05%, 60.21% and 57.89%, respectively） in the pesticide/heavy metals coexisting sediment system. The synergistic effects of the main effects and double-order interaction effects of pollutants concentration（synergistic effects） played a leading role in adsorption of malathion and prometryn（the rates of contributions were 70.61% and 69.61%, respectively）, while an- tagonistic effects of the main effects and double-order interaction effects of pollutants（antagonistic effects） played a dominant role in the adsorption of dimethoate, metalaxyl and atrazine（the rates of contributions were 58.82%, 56.89% and 58.24%, respectively）. Moreover, the correlation coefficient value（R2） ranged from 0.986 to 0.999（〉0.8783） in the 2D-QSAR model, while the standard deviation（SD） ranged from 0.006 to 0.066 and the Ftest values were 22.684-199.544, indicating the model has good predictive ability and fit. The 2D-QSAR model revealed a significant correlation（P=0.05） between the main effects of pollutants concentrations on pesticides adsorption（main effect values） and the most positive hydrogen atomic charge（qa＋）, the highest occupied molecular orbital energy（EHOMO） and the dipole moment（μ）. Furthermore, double-order interaction effect values of pollutant concentrations influenced the adsorption of pesticides（double-order interaction effect values）, and the most positive atomic charge（q＋）, qH＋, and the lowest unoccupied molecular orbital energy（ELMO） were significantly correlated. The qw, EHOMO and μ of pesticides were found to be significant factors promoting pesticides adsorption, while the q＋ and ELVMO of pesticides were significant inhibiting factors（P=0,05）. Overall, this study provides a theoretical basis for further realization of combined pollution control of pesticide pollutants in complex environmental systems.展开更多
Apple orchard surface soils in Japan are polluted with copper (Cu), lead (Pb), and arsenic (As) due to long-term use of metal-based pesticides. We investigated the effects of heavy metals accumulated in the surface so...Apple orchard surface soils in Japan are polluted with copper (Cu), lead (Pb), and arsenic (As) due to long-term use of metal-based pesticides. We investigated the effects of heavy metals accumulated in the surface soils in apple orchards on the microbial biomass and the microbial communities. Soil samples were taken from a chestnut orchard (unpolluted control) and five apple orchards with different degrees of heavy metal pollution. Total concentrations of Cu, Pb, and As in soil ranged from 29 to 931 mg/kg, 35 to 771 mg/kg, and 11 to 198 mg/kg, respectively. The amount of microbial biomass carbon expressed on a soil organic carbon basis decreased with increasing concentrations of heavy metals. Thus, the heavy metals that accumulated in apple orchard surface soils had adverse effects on the soil microbial biomass. The analysis of phospholipid fatty acid (PLFA) composition indicated that the microbial community structure had changed because of the pesticide-derived heavy metals in soil. The relative abundance of gram-positive bacterial marker PLFAs increased and that of fungal marker PLFA decreased with increasing concentrations of heavy metals in soil. Denaturing gradient gel electrophoreses targeting the 16S ribosomal RNA gene of bacteria and the 18S ribosomal RNA gene of fungi also showed shifts in the composition of bacterial and fungal communities induced by soil pollution with heavy metals. However, the diversity of microbial communities was not significantly affected by the heavy metal pollution. This was attributable to the adaptation of the microbial communities in apple orchard surface soils to heavy metals derived from previously used pesticides.展开更多
基金Development of Huotanmu Capsules,a New Zhuang Ethnic Medicine for the Treatment of Hepatitis B(20183046-1)Collaborative Innovation Center of Zhuang and Yao Ethnic Medicine(GJKY[2013]20)+2 种基金Guangxi Key Laboratory of Zhuang and Yao Ethnic Medicines(GKJZ[2014]32)Guangxi Key Discipline:Zhuang Pharmacology(GJKY[2013]16)First-class Discipline in Guangxi of Traditional Chinese Pharmacology(Direction of Ethnic Medicine)(GJKY[2018]12).
文摘[Objectives]This study was conducted to determine the contents of such five heavy metals as lead(Pb),cadmium(Cd),arsenic(As),mercury(Hg)and copper(Cu)and the contents of nine kinds of organochlorine pesticide residues including total BHC(α-BHC,β-BHC,γ-BHC,δ-BHC)and total DDT(pp-DDE,pp-DDD,op-DDT,pp-DDT)and pentachloronitrobenzene in the Zhuang medicine Herba Polygoni Chinensis from 13 producing areas.[Methods]The five heavy metals were determined in accordance with the second method of general rule 2341,the inductively coupled plasma mass spectrometry method,in part 4 of the 2020 edition of Chinese Pharmacopoeia;and the nine organochlorines were determined in accordance with the first method of general rule 2341,organochlorine pesticide residue determination method(chromatography),in part 4 of the 2020 edition of Chinese Pharmacopoeia.[Results]In the Herba Polygoni Chinensis from 13 origins,the lead contents were in the range of 0.50-3.28 mg/kg;the cadmium contents were in the range of 0.06-4.21 mg/kg;the arsenic contents were in the range of 0.16-6.9 mg/kg;the copper contents were in the range of 10.5-45.1 mg/kg;the mercury contents were in the range of 0.00-0.003 mg/kg;and the nine organochlorines including the total benzene hexachloride(α-BHC,β-BHC,γ-BHC,δ-BHC),total DDT(pp-DDE,pp-DDD,op-DDT,pp-DDT)and pentachloronitrobenzene were all not detected.Referring to part 4 of the 2020 edition of Chinese Pharmacopoeia,the Cu and As of the Herba Polygoni Chinensis produced in Hezhou exceeded the standards,the Cu of the Herba Polygoni Chinensis produced in Wuzhou exceeded the standard,and the As of the Herba Polygoni Chinensis produced in Yulin City and Guilin City exceeded the standard.[Conclusions]This study provides safety limit test data for the development and utilization of Herba Polygoni Chinensis of the Zhuang medicine.
基金Supported by the Project of National Natural Science Foundation of China(81460587)Project for Improving Basic Research Ability of Middle Aged and Young Teachers in Colleges and Universities of Guangxi in 2019(2019KY0310)+4 种基金Doctoral Starting up Foundation of Guangxi University of Chinese Medicine in 2018(2018BS019)Program of Collaborative Innovation Center of Zhuang and Yao Medicine(Gui Jiao Ke Yan[2013]No 20)Program of Key Laboratory of Zhuang and Yao Medicine(Gui Ke Ji Zi[2014]No.32)Program of Key Discipline of Guangxi(Zhuang Medicine Discipline)(Gui Jiao Ke Yan[2013]No.16)Innovation Research Program of Postgraduates of Guangxi University of Chinese Medicine(YCSY20190038)
文摘[Objectives]To establish a method for the determination of heavy metals and pesticide residues in Dendrobium officinale produced in Guangxi and its culture substrate.[Methods]The contents of five heavy metals(Pb,Cd,As,Hg and Cu)were determined by the atomic absorption spectrophotometric(AAS)method;residues of 9 organochlorine pesticides(α-BHC,β-BHC,γ-BHC,δ-BHC,p,p′-DDT,p,p′-DDE,p,p′-DDD,o,p′-DDT and pentachloronitrobenzene)were determined by gas chromatography(GC).[Results]The contents of five heavy metals in the medicinal materials of D.officinale produced in Guangxi were 0.96,0.21,0.021 mg/kg,and not detected,and 0.35 mg/kg.The contents of five heavy metals in the culture substrate were 0.03,0.19,0.21,0.004 and 1.80 mg/kg,respectively;the content of 9 organochlorine pesticide residues in the sample was not detected.[Conclusions]The detection results of heavy metal content and organochlorine pesticide residues in D.officinale produced in Guangxi and its substrate are consistent with the limit requirements of the Chinese Pharmacopoeia.This experiment is expected to provide reliable data reference for ensuring the safety of the drug resources of D.officinale in Guangxi.
文摘This study assessed sediment contamination by heavy metals and pesticide active ingredients linked to chemical inputs used in agricultural activities in the lower Ouémé. Pesticide residues from the organochlorine, pyrethroid and organophosphorus families were investigated by gas chromatography, and heavy metals (Cd, Pb, As, Ni, Zn, Fe, Mg, Cr and Hg) by atomic absorption spectrophotometry. The metallic pollution indices, the contamination factor (CF) and the ecological risk index were calculated. The results revealed 8 active ingredients in the rainy season and 9 in the dry season. Glyphosate was the active ingredient with the highest concentration at all stations, 9.65 ± 0.84 mg/kg recorded in the dry season at the Aguigadji station. All glyphosate values were above the EQS. DDT, Atrazine and Endosulfan also showed high concentrations in the dry and rainy seasons. Emamectin, Abamectin and Lambda Cyhalothrin also showed high concentrations in the dry season at Aguigadji, Ahlan and Sele. Only glyphosate was recorded at the control station (Toho), but in very low concentrations. Lead showed the highest concentrations at all the stations, 265.96 ± 21.02 mg/Kg in the rainy season and 255.38 ± 79.09 mg/Kg in the dry season, all detected at the Aguigadji station and above the EQS. Zn, Ni, Fe, Cu and Cr were all representative in both the dry and rainy seasons at the contaminated stations. Manganese showed high concentrations in the rainy season. Pb showed very high contamination (FC ≥ 6) at the Aguigadji and Ahlan stations and significant contamination (3 ≤ FC 6) at the Sele station in both the rainy and dry seasons. Ni, Hg and Cd, showed either moderate or significant contamination at the contaminated stations. The risk values showed a considerable ecological Ri (190 ≤ Ri < 380) in the rainy season and a moderate ecological Ri (95 ≤ Ri < 190) in the dry season at these contaminated stations.
文摘Objective: The main objective of this study was to assess the degree of contamination of surface waters by heavy metals and pesticides. Method: To this end, data were collected in December 2022 from four specific sampling stations: Okpara, Térou, Affon and Adjiro. Levels of heavy metals, including cadmium, chromium, copper, iron, mercury, nickel and lead, were measured and subjected to in-depth statistical analysis using graphical summation models. In addition, the concentrations of pesticide active ingredients present in the samples were interpreted and evaluated. The statistical data collected during this study were processed using R software, version 3.5.0. Results: The values obtained at the different stations Okpara, Térou, Affon and Adjiro are respectively Arsenic (2 × 10<sup>-4</sup> mg/L;2.2 × 10<sup>-1</sup> mg/L;1.2 × 10<sup>-4</sup> mg/L;2 × 10<sup>-4</sup> mg/L), Cadmium (4.4 × 10<sup>-5</sup> mg/L;1.1 × 10<sup>-2</sup> mg/L;10<sup>-4</sup> mg/L;4 × 10<sup>-4</sup> mg/L). Then Copper (7 × 10<sup>-4</sup> mg/L;3 × 10<sup>-3</sup> mg/L;7 × 10<sup>-4</sup> mg/L;1 × 10<sup>-4</sup> mg/L), Iron (1.51 mg/L;6.4 × 10<sup>-1</sup> mg/L;2.0012 mg/L;2.9 × 10<sup>-1</sup> mg/L), Lead (0 mg/L;0 mg/L;1.5 × 10<sup>-3</sup> mg/L;1.5 × 10<sup>-3</sup> mg/L). Mercury, nickel and chromium were not detected in surface waters. It is important to note that the values obtained for trace metals (Cadmium, Chromium, Copper, Iron, Mercury, nickel and chromium were not detected in surface waters. It is important to note that the values obtained for trace metals (cadmium, chromium, copper, iron, mercury, nickel and lead) were all below the guideline standards set by the WHO in 2006 for uncontaminated surface waters. This indicates that the surface waters of the Upper Ouémé were below acceptable contamination thresholds in terms of heavy metals. However, the presence of pesticide active ingredients such as cyfluthrin, endosulfan-alpha, endosulfan-beta, profenosfos, tihan, atrazine, gala super and glycel clearly indicates that these surface waters are subject to agricultural contamination.
文摘The toxicity of heavy metals (Hg2 + , Zn2 + ) and pesticides has been investigated by comparing the physiological properties in wild and tolerant strains of Synechococcus cedrorum 1191. The differential pattern of growth, absorption spectra of pigments and nutrient uptake was observed in tolerant strain.
基金Project(50925417) supported by the National Natural Science Funds for Distinguished Young Scholar of ChinaProject(2010AA065203) supported by the High Technology Research and Development Program of China+2 种基金Project(2010-609) Supported by the Scientific Research Foundation for the Returned Overseas Chinese Scholars,Ministry of Education,ChinaProject(ncet-10-0840) supported by Program for New Century Excellent Talents in UniversityProject(2012FJ1080) supported by Key Projects of Science and Technology of Hunan Province,China
文摘Four different methods,namely mineralogical analysis,three-stage BCR sequential extraction procedure,dynamic leaching test and Hakanson Potential Ecological Risk Index Method were used to access the environmental activity and potential ecological risks of heavy metals in zinc leaching residue.The results demonstrate that the environmental activity of heavy metals declines in the following order：CdZnCuAsPb.Potential ecological risk indices for single heavy metal are CdZnCuAsPb.Cd has serious potential ecological risk to the ecological environment and contributes most to the potential toxicity response indices for various heavy metals in the residue.
基金Supported by the Guizhou Provincial Education Department of Education's Youth Science and Technology Project Fund Grant No.161/2016(Q-J-H-KY)the Science and Technology Planning Project of Guizhou Science and Technology Department Project Fund grant No.1074/2018(Qian-ke-he-basic)
文摘Taking three mains edibles products(walnut, prickly ash and bamboo shoots) and origin soil in central area of Sichuan Province as the study objects, this research aimed at revealing the level of heavy metals and pesticide residue and comprehensive evaluation the soil heavy metal pollution in the region. The results showed that: ① Soil organic matter, total nitrogen, total phosphorus and heavy metal contents of mercury, arsenic in the south area were significant higher than that in the north area, while the heavy metal contents of lead and copper were significantly higher in the north area; ② The pollution index of six heavy metals of cadmium, mercury, arsenic, lead, chromium and copper in the producing area was less than 1.0. However, the integrated pollution index was at a warning level, and there was a potential risk of cadmium contamination; ③ The walnut samples exceeded the lead limit value over 75% in the north area and over 35% in the south area, and the same as 30% of bamboo shoot samples; ④ There was a significant negative correlation of mercury content between walnut samples and production soil, and a significant positive correlation of arsenic content between bamboo shoots and production soil. In addition, there is no significant correlation of heavy metal contents between prickly samples and production soil; ⑤ Fenthion residues were detected in walnuts, malathion samples were detected in prickly ash, and chlorothalonil, dimethoate and chlorpyrifos residues in bamboo shoots samples. None of theses pesticide residues exceeded the standard limit value. In general, the soil is in well sanitary condition and the edible forest products are not exposed to the contamination of pesticide residues in the study area. The quality and safety of the prickly ash is good while the walnut and bamboo shoots have certain risks in terms of high lead level.
文摘The levels of common pesticides and heavy metals in Dendrobium officinale grown from 2012 to 2014 were measured, and three planting methods were used in 2014. The quality of plant husbandry improved during the study period. Thirteen types of pesticides were detected in D. officinale grown in 2014 and antimicrobials, including carbendazim, difenoconazole and azoxystrobin, were evident in 61.53% of plants. These three pesticides constituted 72.33% of all the antimicrobials detected. Planting methods affected the levels of pesticides and heavy metals. Trellising in plastic sheds was optimal, being associated with the lowest amounts of both pesticides and heavy metals. Both cadmium（Cd） and lead（Pb） levels were high in treed plants, whereas Cr, As and Cu levels were the highest in potted plants.
文摘Urban soil is the main component of urban ecological systems and the key risk receptor from urbanization. Heavy metal and green pesticide pollutions in urban soils have been widely reported with the expanding of urbanization. Since urban soil pollution comes from various resources, application of integrated thinking and methods is needed in ecological risk assessment of urban soil pollution. This paper synthetically reviewed the combined pollution of heavy metals and pesticide, and ecological risk assessment, and then proposed some research trends and areas in the future that are required to carry out intensively according to the present situation of environmental pollution and international research fronts.
基金Supported by International Science&Technology Cooperation Program of China(2015DFR70390)Science and Technology Platform and Base Construction Project of Chongqing City,China(cstc2014gjhz20001)Science and Technology Planning Project of Chongqing City,China(cstc2011pt-gc80019)
文摘Low temperature plasma was used to treat sludge,and the effects of discharge time on the content of different forms of heavy metals in the sludge were studied. The results showed that Cu and Zn content in the domestic sludge could basically meet the requirements of GB 4284-2018,GB/T 23486-2009,CJ/T 362-2011 and CJ/T 309-2009. There were big differences between different forms of the heavy metals. According to the proportions of different forms of Cu in the sludge,different forms of Cu are arranged as follows: organic state > carbonate bound state> residual state > exchangeable state > iron-manganese oxidation state,and Cu mainly existed in an organic state. Various forms of Zn are arranged in order of the proportion as follows: iron-manganese oxidation state > residual state > carbonate bound state > exchangeable state > organic state,and Zn mainly existed in an iron-manganese oxidation state. After the treatment of sludge by low temperature plasma,the content of exchangeable Cu and Zn in the sludge increased,while the content and proportion of residual Cu and Zn all reduced.
文摘Fishponds waters intended to satisfy the nutritional needs of the populations in terms of supply of fish resources are strongly and unfortunately exposed to the mobility and dispersion of metallic trace elements (TMEs) or to the persistence in the environment and in the form of pesticide residues from human activities. The objective of this work is to evaluate, on the one hand, the levels of identified pesticide residues and, on the other hand, those of researched TMEs (lead, cadmium, mercury and arsenic) in the waters of ponds used for fish farming in Zépréguhé, a locality located 9 km from the town of Daloa in the centre-west of Côte d’Ivoire. The dosage of the samples carried out by means of a gas chromatograph coupled to a mass spectrometer (GC/MS) made it possible to detect nine (9) pesticide molecules, including eight (8) organochlorines and a single molecule from the pyrethroid family, obtained from the detection limit of 0.006 μg/L and the quantification limit of 0.018 μg/L. The maximum average concentration was obtained with α-endosulfan for a content reaching 0.8038 μg/L and well above the maximum admissible concentration of 0.1 μg/L. The TMEs were quantified using an atomic absorption spectrophotometer (AAS). Arsenic is the most abundant metal with an average concentration of 9.497 μg/L. With the exception of lead, these measured levels are above the acceptable limit values for freshwater. This study showed that human activities such as the use of fertilisers and plant protection products in plantations, sand extraction and road traffic have a negative impact on the quality of the water in ponds used for fish breeding.
文摘This study investigates the concentrations of metals in leafy vegetables in Bethlehem and Jenin districts in Palestine. The concentrations of Fe, Pb, Cr, Co, Cu, Mn, Cd, and Zn were measured. Vegetables including spinach, arugula, and parsley were collected from different farms from both regions, and analyzed by using ICP-MS. In Bethlehem region, Iron concentrations were ranged from 25 to 1046 mg/kg. Iron concentrations were higher than the WHO/FAO limits of 425 mg/kg in 33% of the samples. Lead concentrations were ranged from 0.04 to 1.77 mg/kg. Lead concentrations were higher than the WHO/FAO limits of 0.3 mg/kg in 40% of the samples. Chromium concentrations were ranged from 0.02 to 2.51 mg/kg. Chromium concentrations were higher than the WHO/FAO limits of 1.3 mg/kg in 13% of the samples. Zinc concentrations were ranged from 4 to 107 mg/kg. Zinc concentrations were higher than the WHO/FAO limits of 99.4 mg/kg in 6.6% of the samples. Cadmium concentrations were ranged from 0.01 to 1.4 mg/kg. Cadmium concentrations were higher than the WHO/FAO limits of 0.2 mg/kg in 13% of the samples. The concentration of Manganese, Cobalt and Cupper were all below the WHO/FAO limits of 500, 50 and 73 mg/kg respectively. In Jenin region, Iron concentrations were ranged from 42 to 543 mg/kg. Iron concentrations were higher than the WHO/FAO limits of 425 mg/kg in 20% of the samples. Lead concentrations were ranged from 0.05 to 0.67 mg/kg. Lead concentrations were higher than the WHO/FAO limits of 0.3 mg/kg in 20% of the samples. Copper concentrations were ranged from 0.62 to 278 mg/kg. Copper concentrations were higher than the WHO/FAO limits of 73 mg/kg in 6.66% of the samples. Cadmium concentrations were ranged from 0.02 to 1.62 mg/kg. Cadmium concentrations were higher than the WHO/FAO limits of 0.2 mg/kg in 6.66% of the samples. The concentration of Chromium, Manganese, Cobalt and Cupper were all below the WHO/FAO limits. It was concluded that the contamination found in some leafy vegetable samples was not related to either irrigation water or soil. It was attributed to the misuse of pesticides.
文摘In Kazakhstan, camel breeding mainly occupies areas sometimes close to polluting industries or other sources of pollu- tion as industrial agriculture, mainly cotton. Products issued from camel farms close to these sources as camel raw milk and fermented milk (shubat), wool and meat, traditionally used by humans could be contaminated. We investigated camel raw milk and fermented milk for the content of heavy metals (lead, cadmium, zinc and copper), radionuclide and some organic pollutants (PAHs, pesticides and indicator PCBs) in samples from different regions with a priori high risk of pollution (Atyrau, Kyzylorda, South-Kazakhstan and Almaty region). In the present paper, only some milk samples presented high lead concentration (> 500 ppb). After analysis for organic pollutants, it was observed some traces of hexachlorocyclohexane, lindane, hexanchlorothalonil in milk samples from different regions. One sample was also slightly contaminated with radionuclide. These preliminary results allow establishing a first map of risk for camel farming. As the whole, South-Kazakhstan appeared the most exposed region.
基金supported by the National Natura Science Foundation of China (No.40473043)
文摘In order to assess the contamination of edible marine organisms in Quanzhou and Xinghua Bays, Fujian Province, China, concentrations of organochlorine pesticides （hexachlorocyclohexane isomers or HCHs and dichlorodiphenyltrichloroethane isomers/derivatives or DDTs） and heavy metals （Cu, Pb, Zn, As, Cr, Cd, Ni and Hg） in 13 species collected from different sites in the hays were analyzed by GC-ECD and ICP-MS. The concentration of the sum of DDTs exceeded that the sum of HCHs in the samples. Most of the organisms showed higher levels of DDTs than the first level criterion （10 ng/g） for marine biological quality in China （GB 18421-2001） but conformed to the first level criterion （20 ng/g） for HCHs. The estimated mean daily uptake of pesticides was below the level for minimal risk to the consumers. The levels of Cd, As and Pb in most organisms from both bays were markedly elevated and above the recommended legal limits for human consumption. Our results showed the need for routine monitoring of marine species contamination to ensure public and environmental health.
基金This work was supported by Tongji Eco-park and biogas project in Chongming County,shanghai.
文摘The presence of high levels of heavy metals in anaerobic fermentation residues is a major obstacle to the resource utilization and urgent research for removal of heavy metals in the biogas slurry is needed.The handling of large-scale residue slurry and safely returning to field urgently needed constructive suggestion.The contents of heavy metal elements in the residue of anaerobic digestion processes of the wastewater and waste of the piggery were mainly investigated.The contents of heavy metals in the original fluid and the centrifugal solution were determined in this study.They included elements,such as Cu,Zn,Cr,Cd,Pb,As,Ni,Mn,and Se,which were compared with the existing standard including the irrigation water quality standards(GB5084-2005),comprehensive discharge standard of sewage(GB8978-1996)and water-solubility humic acid fertilizer quality standards(NY1106-2010).The preliminary data suggested that both the heavy metals before and after centrifugation were in excess of the standards to some degree and the exceeding standard rate declined significantly after centrifugation.The absolute contents of heavy metals after centrifugation declined significantly compared with that before centrifugation.Those ratios are 91.8%,73.2%,47.6%,94.5%,93.5%,59.4%,95.8%,100%for Zn,As,Cd,Cr,Cu,Ni,Mn,Pb,respectively.A descriptive statistics as well as a correlational analysis showed that there existed strong correlation among Cu,Pb,and the total suspended solids(TS).Meanwhile,significant correlation was found among TS,Cd,Zn,As,Cr,Ni,and Mn at 0.01 level.The data and the analysis above provided the theoretical and experimental support for the removal of heavy mental mainly characterized by the removal of TS.According to the comparison between contents of heavy mental conversed from large amount nutrients and corresponding standard(NY1110-2006),only as was found beyond standard.It was feasible to apply biogas residues after centrifugation as water-solubility fertilizer due to the fact that As had low accumulation efficiency in soil and plants.
基金Supported by the National Basic Research Program of China (Grant No. 2003CB415001)Chinese Academy of Sciences (Grant No. KZCX3-SW-431)
文摘Concentrations of polybrominated diphenyl ethers (PBDEs), organochlorine pesticides (OCPs) and heavy metals in two sediment cores, taken from the Dagu Drainage River, were determined. The contamination trends of these three kinds of compounds were obtained. The results showed that concentrations of PBDEs increased in recent years; there were new contamination sources for OCPs in this area; contamination levels of heavy metals had no significant change in the last several years. Comparing the results of these two cores, erosion and dilution of seawater had different effects on the transportation of these compounds.
文摘The mechanisms of adsorption of pesticides（dimethoate, metalaxyl, atrazine, malathion and prometryn） and heavy metals（Cu, Cd, Pb, Zn and Ni） coexisting in sediments, with pesticides as target pollutants, and the influence of their main effects and double-order interaction effects were studied using the experimental design module in the Minitab software package with a 2^10-3 fractional factorial design method at resolution V. The main, double-order interaction, synergistic and antagonistic effect values of pollutant concentrations influencing the adsorption of pesticides were set as dependent variables, while various quantum chemical parameters of pesticides were set as independent variables, and two-dimensional quantitative structure activity relationship（2D-QSAR） models were established by stepwise regression to reveal the adsorption mechanisms of pesticides in a composite contamination system. The main effects of pollutants concentration played the primary role in the adsorption of dimethoate and malathion（the rates of contributions were 53.54% and 56.46%, respectively）, while double-order interaction effects were primarily responsible for metalaxyl, atrazine and prometryn adsorption（the rates of contributions were 79.05%, 60.21% and 57.89%, respectively） in the pesticide/heavy metals coexisting sediment system. The synergistic effects of the main effects and double-order interaction effects of pollutants concentration（synergistic effects） played a leading role in adsorption of malathion and prometryn（the rates of contributions were 70.61% and 69.61%, respectively）, while an- tagonistic effects of the main effects and double-order interaction effects of pollutants（antagonistic effects） played a dominant role in the adsorption of dimethoate, metalaxyl and atrazine（the rates of contributions were 58.82%, 56.89% and 58.24%, respectively）. Moreover, the correlation coefficient value（R2） ranged from 0.986 to 0.999（〉0.8783） in the 2D-QSAR model, while the standard deviation（SD） ranged from 0.006 to 0.066 and the Ftest values were 22.684-199.544, indicating the model has good predictive ability and fit. The 2D-QSAR model revealed a significant correlation（P=0.05） between the main effects of pollutants concentrations on pesticides adsorption（main effect values） and the most positive hydrogen atomic charge（qa＋）, the highest occupied molecular orbital energy（EHOMO） and the dipole moment（μ）. Furthermore, double-order interaction effect values of pollutant concentrations influenced the adsorption of pesticides（double-order interaction effect values）, and the most positive atomic charge（q＋）, qH＋, and the lowest unoccupied molecular orbital energy（ELMO） were significantly correlated. The qw, EHOMO and μ of pesticides were found to be significant factors promoting pesticides adsorption, while the q＋ and ELVMO of pesticides were significant inhibiting factors（P=0,05）. Overall, this study provides a theoretical basis for further realization of combined pollution control of pesticide pollutants in complex environmental systems.
文摘Apple orchard surface soils in Japan are polluted with copper (Cu), lead (Pb), and arsenic (As) due to long-term use of metal-based pesticides. We investigated the effects of heavy metals accumulated in the surface soils in apple orchards on the microbial biomass and the microbial communities. Soil samples were taken from a chestnut orchard (unpolluted control) and five apple orchards with different degrees of heavy metal pollution. Total concentrations of Cu, Pb, and As in soil ranged from 29 to 931 mg/kg, 35 to 771 mg/kg, and 11 to 198 mg/kg, respectively. The amount of microbial biomass carbon expressed on a soil organic carbon basis decreased with increasing concentrations of heavy metals. Thus, the heavy metals that accumulated in apple orchard surface soils had adverse effects on the soil microbial biomass. The analysis of phospholipid fatty acid (PLFA) composition indicated that the microbial community structure had changed because of the pesticide-derived heavy metals in soil. The relative abundance of gram-positive bacterial marker PLFAs increased and that of fungal marker PLFA decreased with increasing concentrations of heavy metals in soil. Denaturing gradient gel electrophoreses targeting the 16S ribosomal RNA gene of bacteria and the 18S ribosomal RNA gene of fungi also showed shifts in the composition of bacterial and fungal communities induced by soil pollution with heavy metals. However, the diversity of microbial communities was not significantly affected by the heavy metal pollution. This was attributable to the adaptation of the microbial communities in apple orchard surface soils to heavy metals derived from previously used pesticides.
