ENVIRONMENTAL MONITORING AND ASSESSMENT
·
2011
·Vol. 184
·期 5
·3085-3094
·
IF 1.436
Li Yongfang,Yang Zhongzhi,Kong Xiaoduo,He Guangjie
As facile “environmental media”, the outdoor dust may reflect the changes of contaminants in environment more promptly. In the present study, selected organochlorine contaminants (OCs) include hexachlorocyclohexanes (HCHs), dichlorodiphenyltrichloroethanes (DDTs), hexachlorobenzene (HCB), and pentachlorobenzene (PeCB) were detected in 20 outdoor dust samples collected from Xinxiang City. The concentrations of ΣHCHs, ΣDDTs, HCB, and PeCB in dust were in the range of 0.18–5.05 ng/g dry weight, 0.44–13.50 ng/g dry weight, 0.13–51.61 ng/g dry weight and ND-0.74 ng/g dry weight, respectively. Long-range transport, historical use, and recent impact of impure pesticides might be the main sources of OCs in the outdoor dust. The results of this study indicated that impure pesticide application maybe an important source of DDTs and HCB in the environment.
研究领域:
环境科学
·
污染生态学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF CHROMATOGRAPHY A
·
2015
·
IF 4.169
Yan-Bo Luo,Xue Li,Xing-Yi Jiang,Bao-Dong Cai,Feng-Peng Zhu,Hong-Fei Zhang,Zai-Gen Chen,Yong-Qiang Pang,Yu-Qi Feng
In this study, magnetic graphene was used as modified quick, easy, cheap, effective, rugged and safe (QuEChERS) adsorbent for the determination of organochlorine pesticide (OCPs) residues in tobacco. To achieve the optimum conditions of modified QuEChERS procedure toward target analytes, several parameters affecting the clean-up efficiency including the amount of the adsorbent and clean-up time were investigated. Under the optimized conditions, a method for the determination of 26 OCPs residues in tobacco was established by coupling the modified QuEChERS procedure to on-line gel permeation chromatography–gas chromatography–tandem mass spectrometry (on-line GPC–GC–MS 2 ). The limits of detection of proposed method for 26 OCPs residues ranged from 0.01275 to 3.150 ng/g. And good linearities of the proposed method were obtained with coefficients of determination ( R 2 ) greater than 0.9985 for all target analytes. Good reproducibility of method was obtained as intra- and inter-day precisions, the relative standard deviations were less than 11.1 and 15.0%, respectively. The apparent recoveries were in the range of 64–126% at different concentrations for real samples. Compared with the reported methods for the determination of OCPs residues in tobacco, the proposed method has the advantages of simple to operate, low cost and high clean-up ability. Finally, the method was successfully applied to the analysis of OCPs residues in real samples.
研究领域:
分析化学
·
环境科学
·
食品安全
✓ 已验证
DOI
PubMed
高影响因子
ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH
·
2019
·Vol. 26
·期 10
·9480-9489
·
IF 2.914
Dai Shijin,Zheng Yilin,Zhao Youcai,Li Qiang,Niu Dongjie
Chlorine-containing organic waste (COWs) is a big threat for the waste incineration because of the dioxin generation and equipment corrosion. Recently, dechlorination and detoxification of COWs is emergent in order to lower the environmental risk and treatment costs. In this study, base-catalyzed decomposition processes with different hydroxides, hydrogen donors, and catalysts were conducted for pre-treatment of COWs to reduce organic chlorine content, with the TCB as a model compound and industrial rectification residues for verification. Results showed that maximum chlorine retention efficiency (CRE) of four alkalis followed the order of KOH > NaOH–KOH > NaOH > Mg(OH) 2 , which were 98.3%, 93.4%, 97.2%, and 1.5%, respectively, and could be expressed as an apparent first-order reaction. The differences were resulted from the varying ionic potentials of the metal cations. Hydrogen donors (glycol, glycerol, paraffin oil, and PEG 200) acted as effective dechlorination regents follow the order of PEG > glycol > paraffin oil > glycerol. In addition, Fe, Ni, Cu, and activated carbon catalysts increased the CRE by 68.9% to 92.4%, 91.9%, 89.2%, and 73.3%, respectively. Residue analysis through X-ray diffraction and Fourier transform infrared spectroscopy revealed that KCl, sodium oxalate, and phenol were the main products and a plausible stepwise dechlorination pathway was proposed. The effectiveness of three optimized combinations including NaOH/PEG, KOH/PEG, and NaOH–KOH/PEG (with the Fe catalyst) was confirmed by using them for dechlorinating rectification residues, and they restrained 98.2%, 91.2%, and 94.6% of the chlorine, respectively. The organochlorine content decreased from 19.2 to 1.8% within 180 min, while inorganic chorine content increased from 1.5 to 18.9%, indicating the potential for COWs dechlorination.
研究领域:
环境科学
·
化学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
WASTE MANAGEMENT
·
2023
·
IF 8.1
Yang Ren,Hongyun Hu,Chengyang Cao,Guangzhao Guo,Xiaodong Zeng,Chan Zou,Xian Li,Hong Yao
Disposal of automobile shredder residue (ASR) via pyrolysis enables the recovery of valuable products; however, the production of hazardous pollutants and low-value products is inevitable due to its high chlorine content. In this work, chlorine evolution behavior and the conversion mechanism during ASR pyrolysis between 480 and 600 °C were systematically studied. The experimental results for organic chlorine (Org-Cl) showed that released chlorinated gases were complex, and HCl only accounted for 35% of the gas phase products, while short-chain hydrocarbons with carbon atoms between two and four accounted for 52%. Chlorine was predominantly retained in the char, and Org-Cl was the primary contributor to the residual chlorine, accounting for over 50% of the char. The content of inorganic chlorine (InO-Cl) was low in the raw sample but significantly increased in the char. Through the distinction between organic and inorganic chlorine content in char, it was confirmed that Org-Cl could be converted to InO-Cl due to complex secondary reactions with metallic compounds. The conversion was favored by increasing the Org-Cl content and the temperature. Our findings clarified the evolution mechanism of chlorine and the transformation from Org-Cl to InO-Cl, thus providing guidance for chlorine regulation and the efficient recycling of metal resources.
研究领域:
环境科学
·
化学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
SCIENCE OF THE TOTAL ENVIRONMENT
·
2023
·
IF 9.8
Peipei Gao,Zichao Hu,Yue Sheng,Weitong Pan,Lu Ding,Longfei Tang,Xueli Chen,Fuchen Wang
The release of chlorine during the pyrolysis of actual municipal plastic waste (MPW) was studied. Firstly, thermogravimetry-Fourier transform infrared (TG-FTIR) was analyzed to investigate the chlorine release behavior. Then, the effect of temperature on chlorine migrations was investigated by fast pyrolysis experiments in a fixed bed reactor. Results showed that chlorine released mainly between 241 and 353 °C in the form of HCl or chloroesters during MPW pyrolysis. After pyrolysis, chlorine was mainly distributed in the pyrolytic gas (74.34–82.89 %) and char (10.17–21.29 %). However, the release of chlorine was inhibited due to the melting behavior of MPW at <350 °C. Besides, the relative contents and types of organic chlorinated compounds in liquid products were both decreased with temperature. It was observed that polyethylene terephthalate (PET) was the greatest contributor to the formation of organic chlorinated compounds during MPW pyrolysis. Meanwhile, the pyrolysis of PET was significantly promoted by the HCl released from polyvinyl chloride (PVC). Subsequently, the pathways for the formation of organic chlorinated compounds through the co-pyrolysis of PVC and PET were proposed, including the initial degradation and subsequent chlorination of PET. These findings provided new insights into the release and regulation of chlorine-containing pollutants during actual MPW pyrolysis.
研究领域:
环境科学
·
化学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ENVIRONMENTAL POLLUTION
·
2023
·
IF 8.9
Fanfan Ju,Liuzhu Chen,Teng Ma,Xiaoli Wang,Zhanqiang Chen,Jiejun Zheng,Xinxing Xia
Studying the geochemical behavior of chlorine is the basis of understanding the chlorine cycle in nature. To explore the spatiotemporal distribution of natural organic chlorine (Cl org ), L layer (litter fall), F–H layer (humification zone), topsoil layer (0–20 cm), and deep soil layer (20–40 cm) samples were collected from 18 sampling sites at different altitudes (851–2918 m) in Shennongjia Forest in May, August, and December. Cl org content was analyzed, and the Cl org stocks were calculated. The major factors affecting the distribution of Cl org were explored. The results revealed that the sum of Cl org content in four layers varied from 7.958 to 184.686 mg/kg, and the highest value was observed in August. Cl org accounted for 46%–77% of total chlorine, with the highest mean ratio in soil layer (0–20 cm). Cl org content exhibited the following trend: F–H layer > L layer > topsoil layer (0–20 cm) > deep soil layer (20–40 cm). The seasonal patterns of Cl org in soil layers were different from that in L and F–H layers, which were mainly controlled by the content and humification degree of organic matter. Cl org storage was much higher in soil layers (61–246 kg/ha) than those in F–H layer (1.1–7.1 kg/ha) and in L layer (0.1–0.8 kg/ha) because of the large thickness of the soil layers. Overall, the Cl org content exhibited an increasing trend with altitude, except at an altitude of approximately 1800 m. Cl org content in L and F–H layers varied more obviously with altitude than that in soil layers. When inorganic chlorine (Cl in ) was not a limiting factor for the chlorination process, Cl org content in L and F–H layers was significantly affected by climate and organic matter controlled by altitude, while Cl org content in soil layers was also mediated by metal ions and pH, and soil particle size. This study could provide a scientific basis for assessing the chlorine cycle in nature.
研究领域:
环境科学
·
土壤学
✓ 已验证
DOI
PubMed
高影响因子
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
·
2024
·
IF 3.8
Bingtian Huang,Qing Sun,Liancheng Bing,Dezhi Han,Guangjian Wang,Fang Wang
Activated carbon (AC) treated with nitric acid (HNO3) and hydrogen peroxide (H2O2) was prepared for the study of the effect of oxygen-containing functional groups on the adsorptive removal of organochlorines from oil. The adsorption performance and physicochemical properties of the adsorbents were tested and analyzed. The results show that the HNO3–H2O2 comodified AC (NPAC) presented the best adsorptive efficiency, especially for the removal of aromatic chlorides. It has been found that the surface chemical groups and the physical texture of AC play major roles in the adsorption performance of organic chlorides. The potential of activated carbon (NPAC) treated with nitric acid and hydrogen peroxide in removing organic chlorine from oil was comprehensively evaluated through experimental data combined with mathematical models of kinetics and equilibrium. The adsorption process conforms to the Freundlich isotherm equation, which proves that there is multilayer adsorption in the adsorption process, and 1,2-dichlorobenzene (DCB) is more easily adsorbed by modified AC. The kinetic results indicate that there is chemical adsorption during the adsorption process, and the diffusion process of organic chlorides in AC is influenced by several factors.
研究领域:
环境科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
Food Analytical Methods
·
2017
·Vol. 11
·期 3
·693-702
·
IF 2.038
Qiu Bo,Wang Xiaochen,Li Haipu,Shu Bin,Li Shan,Yang Zhaoguang
A simple and rapid method applying acetonitrile extraction, dispersive-solid-phase extraction (d-SPE) cleanup, and dispersive liquid-liquid microextraction based on solidification of floating organic droplet (DLLME-SFO) was developed for determination of organochlorine pesticides in vegetables. In order to simplify operation, d-SPE cleanup was integrated to DLLME-SFO concentration procedure, and a protection device for glass tube was applied to achieving high-speed centrifugation. The comparison study between the integrated d-SPE and normal d-SPE showed that the former could shorten the sample preparation time without decrease of cleanup efficiency. Subsequently, the necessity of using a high-centrifugation speed (more than 8603 g) for complete separation of the d-SPE sorbents, water phase, and organic phase was confirmed through turbidity analysis. The recoveries of the proposed method ranged from 77.2 to 112.5%, and the relative standard deviations were less than 15%. The limits of detection were in the range of 0.45 ~ 1.33 μg kg −1 , while the limits of quantitation were from 1.35 to 3.99 μg kg −1 , respectively. Finally, the method was successfully applied to analyze real vegetable samples.
研究领域:
分析化学
·
食品科学
✓ 已验证
产品关联
DOI
高影响因子
ANALYST
·
2015
·Vol. 141
·期 3
·1127-1135
·
IF 4.107
Shuaihua Zhang,Qian Yang,Zhi Li,Wenchang Wang,Chun Wang,Zhi Wang
A new solid-phase microextraction (SPME) fiber coating material, a zeolitic imidazole framework-67 (ZIF-67) templated nanoporous carbon, Co-NPC, was fabricated by one-step direct carbonization of ZIF-67 without using any other carbon precursors. The prepared Co-NPC was then coated onto a functionalized stainless steel wire by a simple physical coating method to prepare SPME fibers. By coupling the Co-NPC coated fiber based SPME with gas chromatography/micro-electron capture detection (GC/μECD), the developed method exhibited low limits of detection (0.07–0.45 ng g−1) and a wide linearity (0.30–50 ng g−1) for the determination of five organochlorine pesticides (OCPs) in vegetable samples. The method was applied to the analysis of cabbage, cucumber and celery cabbage samples, and the recoveries of the analytes were in the range of 87.9–103.9% with the relative standard deviations (RSDs) ranging from 5.1% to 10.4% (n = 5). Single fiber repeatability and fiber-to-fiber reproducibility values expressed as RSDs were in the range of 4.9–9.6% and 5.8–11.0%, respectively. The method was simple, convenient and feasible for the determination of OCPs in real samples.
研究领域:
分析化学
·
环境科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
FOOD CHEMISTRY
·
2023
·
IF 8.8
Xiumin Yang,Junmin Wang,Guifen Chang,Cuihong Sun,Qiuhua Wu,Zhi Wang
Analysis of organochlorine pesticides (OCPs) residues in milk faces a significant challenge. Herein, a sea urchin structured covalent organic framework bearing boric acid groups named COF-B(OH) 2 was synthesized and applied as a coating material for solid-phase microextraction (SPME) of the OCPs in cattle’s milk. Its performance was superior to that of three commonly used commercial SPME fibers, which could be due to the coexistence of hydrogen bonding , halogen bonding, π-stacking and electrostatic interactions. Besides, the fiber coating displayed good stability and reusability. After optimization, a COF-B(OH) 2 based SPME coupled with gas chromatography-electron capture detection was established for the sensitive detection of the OCPs from milk samples. The limits of detection (S/N = 3) were between 0.04 and 1.00 μg kg −1 . Satisfactory accuracy was achieved with the method recoveries in the range of 87.5 % to 112.5 %. These results manifest the feasibility of the COF-B(OH) 2 coated fiber for the enrichment of the trace OCPs from milk samples.
研究领域:
分析化学
·
食品科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF HAZARDOUS MATERIALS
·
2025
·
IF 11.3
Yuheng Chen,Longjie Cheng,Pavel Nesterenko,Boqiang Li,Haolin Yang,Xiao Li,Lan Li,Baiyang Chen
Free chlorine (FC), primarily existing as hypochlorite anion in alkaline water (pK a 7.5), could theoretically be analyzed by an ion chromatography (IC) system. However, the feasibility of direct FC detection by IC remains controversial in previous researches. To address this issue, this study systematically examined the fate of FC under varying IC eluent pH, anion exchange column (AEC) types, detectors, and suppression conditions. The results ultimately disprove it and show that the primary obstacle to direct FC analysis with IC system is its transformation: 31 %–41 % became Cl - and 59 %–69 % became immobile organic chloramines in AEC, due to its reaction with quaternary ammonium compounds (QACs) in AECs. Moreover, IC analysis of Cl - might be interfered by coexisting FC, although FC concentrations are typically much lower than Cl - . Eluent suppressor can also consume FC even when residual FC after AEC is limited. In contrast, variations in water pH do not affect FC stability, and a UV detector effectively distinguishes FC from other anions. This study hence for the first time elucidates several FC consumption mechanisms in IC system, which represent key barriers hindering FC analysis by IC, and accordingly provide some guidance on future efforts to develop novel AEC to overcome these barriers.
研究领域:
环境科学
·
分析化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF FOOD PROTECTION
·
2021
·
IF 2.077
Lijun Xu,Meiqing Ren,Yue Cui,Xiaohuan Miao,Zhaoguang Yang,Haipu Li
ABSTRACT The present study was conducted to reveal the concentrations and patterns of organochlorine pesticides (OCPs) and polychlorinated biphenyls (PCBs) in seven species of freshwater food products ( Procambarus clarkii, Ctenopharyngodon idellus, Parabramis pekinensis, Hypophthalmichthys molitrix, Cyprinus carpio, Aristichthys nobilis, and Carassius auratus ) collected from aquaculture farms around Changsha, People's Republic of China. The OCPs and PCBs in the muscle tissue of these species were analyzed to assess the health risk associated with dietary intake. The mean concentrations of OCPs and PCBs were 6.38 to 15.90 and 3.18 to 5.12 ng g −1 wet weight, respectively. Heptachlor and δ-HCH were the main OCP contaminants in the tested samples, accounting for >74% of the total OCPs. PCB52 was the main PCB, accounting for >88% of the total PCBs. The bioaccumulation of OCPs and PCBs in these aquatic products depends upon the species. C. idellus had the highest concentrations of OCPs, and H. molitrix had the highest concentrations of PCBs. The mean lipid concentration in these freshwater species was 6.08 to 19.8% (dry weight) and was significantly correlated with the concentrations of OCPs and PCBs. The health risk from consumption of these freshwater species was assessed based on the hazard ratios and hazard quotient , and consumption of these products was determined to pose a carcinogenic risk.
研究领域:
环境科学
·
毒理学
·
公共健康
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）