Study on Detection of Organochlorine Pesticide Residue in Ginseng

To investigate the residue situation of pesticides in ginseng, total 17 samples of ginseng-growing soil, ginseng roots and ginseng seeds were collected from 5 regions of Fusong County, and the contents of organochlorine pesticide residues in the samples were detected by using ultrasonic-assisted extraction and gas chromatography with acetone-ligroin as the solvent, thereby providing suitable recommendations and scientific basis for the selection of ginseng-growing soil.

Advances in Analytical Techniques for Organochlorine Pesticide Detection in Tea Samples

The pretreatment and analytical techniques for organochiorine residues, including ultrasonic extraction, accelerated solvent extraction pesticide microwave extraction, solid phase extraction, and solid-phase micro-extraction and the analytical techniques of gas chromatography and gas chromatography-mass spectrometry）in tea samples in recent years were reviewed. The prospect of organochlorine pesti- cide residue analysis was proposed in this paper.

Potentialities of Maize on the Removal of Organochlorine Pesticides from Contaminated Soils

In this paper, glasshouse experiments were conducted to determine the accumulation, distribution and transformation of DDTs and HCHs by maize under pot culture conditions. The culture soil was spiked with the organic pollutants and samples were collected in different durations. Analysis of the plants at harvest showed that the selected plant varied widely in their ability to remove and translo- cate DDTs and HCHs from the soil, the bioconcentration factor ranged from 0.004 to 0.027 for the shoot and from 0.036 to 0.097 for the roots, and the translocation factors were lower than 0.1 with variation between DDTs and HCHs, but no signifi- cant differences were observed. DDTs appeared to have accumulated by both pas- sive adsorption and active absorption, p,p＇-DDT and p,p＇-DDE were the major metabolite and the transformation was mediated by reductive dehalogenation, the affinity of the OCPs for lipids is one of the major factors affecting their uptake and translocation within the plants.

Residual Characteristics of Organochlorine Pesticides in Lou Soils with Different Fertilization Modes

Soll samples with three fertilization treatments （no fertilizer, corn straw and farm manure） collected from a Lou soil （Eum-orthic Anthrosol classfied using Chinese Soil Taxonomy） in northwestern China were analysed for residual levels and their characteristics of organochlorine pesticides （α-HCH, β-HCH,γ-HCH, δ-HCH, HCB, o, p＇-DDT, p, p＇-DDT, o, p＇- DDE, p,p＇-DDE, p,p＇-DDD, α-endosulfan, dieldrin and endrin）. Organochlorine pesticides （OCPs） were detected in all soil samples except δ-HCH and their total concentrations ranged from 159.31 ± 9.00 to 179.77 ± 2.58 ng g^-1 with an order of HCHs 〉 DDTs 〉 （dieldrin ＋ endrin） 〉 HCB 〉 α-endosulfan. Among all the compounds, γ-HCH had the highest concentration followed by p, p＇-DDE. The residual levels of HCH isomers and DDT as well as their metabolites in soil with different fertilization treatments were in the order of γ-HCH 〉β-HCH ≈ α-HCH 〉 δ-HCH and p,p’-DDE 〉 p, p’-DDT 〉 o,p＇-DDT 〉 p, p＇-DDD ≈ o, p＇-DDE, respectively. DDE/DDT ratios ranged from 1.59 ± 0.13 to 3.35± 0.16 and endrin/dieldrin ratios from 1.40 ±0.06 to 9.20± 4.05, both indicating no new occurrence of these pesticides in these soils, while α-HCH/γ-HCH ratios of 0.04 indicated a new input of lindane （almost pure γ-HCH） in the past several years. The farm manure treatments showed lower DDT residues than samples without fertilizer. Also addition of corn straw and farm manure increased soil organic matter content and decreased the soil pH which could retard the degradation of DDT in the soil.

Extraction of Organochlorine Pesticides in Sediments Using Soxhlet,Ultrasonic and Accelerated Solvent Extraction Techniques

The application of soxhlet, ultrasonic and accelerated solvent extractiontechniques to the analysis of six organochlorine pesticides (α-HCH, β-HCH, γ-HCH, o, p'-DDT,p,p'-DDT and p,p'-DDE) in Taihu Lake sediment samples is described. It was found that the limits ofquantification ranged from 0.002 μg g^(-1) to 0.004 μg g^(-1), and the recoveries oforganochlorine pesticides with the three extraction techniques were acceptable ( 】80.7%). With amass selective detector, better results were obtained by accelerated solvent extraction usinghexane-acetone (1:1) as compared with soxhlet and ultrasonic extraction. It was shown that theaccelerated solvent extraction was the optimum technique for the analysis of organochlorinepesticides in sediments. The general features of the three extraction techniques are also presented.

Organochlorine pesticides and polycyclic aromatic hydrocarbons in water and sediment of the Bosten Lake,Northwest China

We evaluated organic pollution in Bosten Lake, Xinjiang, China, by measuring the concentrations and distributions of organochlorine pesticides （OCPs） and polycyclic aromatic hydrocarbons （PAHs）. Water and sediment samples were collected from 19 sites 031-1319） in the lake for analysis. Our analytical results show that the concentrations of total OCPs in water ranges from 30.3 to 91.6 ng/L and the concentrations of PAHs ranges from undetectable （ND） to 368.7 ng/L. The concentrations of total OCPs in surface （i.e., lake bottom） sediment ranges from 6.9 to 16.7 ng/g and the concentrations of PAHs ranges from 25.2 to 491.0 ng/g. Hexachlorocyclohexanes （HCHs） and dichlorodiphenyltrichloroethanes （DDTs） account for large proportions of the OCPs. Low α- to γ-HCH ratios in both water and sediment samples indicate possible contributions from both industrial products and lindane. DDTs in water are probably from historical input, whereas DDTs in sediments are from both historical and recent inputs. Moreover, DDT products in both water and sediments were from multiple sources in the northwestern part of the lake（B11, B12, B13, and B14）. Fugacity ratios for DDT isomers （p,p＇-DDE and p,p＇-DDT） at these sites were generally higher than equilibrium values. These results suggest that the input from the Kaidu River and diffusion of DDTs from the sediment to the water are responsible for DDT pollution in the water. Lower-molecular-weight PAHs, which originate primarily from wood and coal combustion and petroleum sources, represent the major fraction of the PAHs in both water and sediment samples. Our findings indicate that OCPs and PAHs in Bosten Lake can be attributed primarily to human activities. A risk assessment of OCPs and PAHs in water and sediment from Bosten Lake, however, suggests that concentrations are not yet high enough to cause adverse biological effects on the aquatic ecosystem.

Reduction of recruitment of Acartia pacifica nauplii from benthic resting eggs due to organochlorine pesticides

Many estuarine and coastal planktonic copepods depend on the hatching of benthic resting eggs for recruitment ofnauplii to the water column population. The potential effects of two organochlorine pesticides, hexchloriobinzene （HCH） and dichlorodiphenyltrichloroethane （DDT）, on the recruitment of A ccu＇tla pacifica nauplii from benthic resting eggs in the seabed of Xiamen Bay were experimentally investigated. The abundance of A. pacifica nauplii hatched from the sediment significantly decreased with the increase of pesticide concentration. Trimmed Spearman-Karber analysis gave sediment 96-h LC50 values were 84.81 ng/g for HCH, and 157.94 ng/g for DDT. The median AI （Al50） was -0.77, which suggested that the combined effect of riCH and DDT showed a weak effect than individual effects. There was a positive relationship between mortality and exposure time in DDT treatment, while the relationship was not significant in HCH treatment. The results suggest that organochlorine pesticides can reduce recruitment of A. pacifica nauplii from benthic resting eggs to planktonic population.

Organochlorine pesticide and heavy metal residues in some edible biota collected from Quanzhou Bay and Xinghua Bay,Southeast China

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.

Residues of organochlorine pesticides in surface soils from college school yards in Beijing, China

Organochlorine pesticides (OCPs) have been a major environmental issue, attracting much scientific concern because of their nature of toxicity, persistence, and endocrine disrupting effects. Soil samples were collected from ten college school yards in Beijing in 2006 and analyzed to determine fifteen OCPs. Dichlorodiphenyltrichloroethanes (DDTs) were found to be the main pollutants, accounting for 93.70% of total OCPs, followed by hexachlorohexanes (HCHs) (2.25%) and hexachlorobenzene (HCB) (1.82%). Content...

Dynamic microwave-assisted extraction combined with liquid phase microextraction based on the solidification of a floating drop for the analysis of organochlorine pesticides in grains followed by GC

A convenient,cost-effective and fast method using dynamic microwave-assisted extraction and liquid phase microextraction based on the solidification of a floating drop was proposed to analyze organochlorine pesticides in grains including rice,maize and millet.Twelve samples can be processed simultaneously in the method.During the extraction process,10%acetonitrile-water solutions containing 110μL of n-hexadecane were used to extract organochlorine pesticides.Subsequently,1.0 g sodium chloride was placed in the extract,and then centrifuged and cooled.The n-hexadecane drops containing the analytes were solidifi ed and transferred for determination by gas chromatography-electron capture detector without any further filtration or cleaning process.Limits of detection for organochlorine pesticides were 0.97–1.01μg/kg and the RSDs were in the range of 2.6%–8.5%.The developed technology has succeeded in analyzing six real grains samples and the recoveries of the organochlorine pesticides were 72.2%–94.3%.Compared with the published extraction methods,the developed method was used to analyze organochlorine pesticides in grains,being more environmentally friendly,which is suitable for the daily determination of organochlorine pesticides.

Concentrations and distribution of organochlorine pesticides in shellfish from Changjiang estuary

To analyze and evaluate the status of organochlorine pollutants in the Changjiang （Yangtze River） estuary and adjacent waters, the concentrations of hexachlorocyclohexane （HCHs） and dichlorodiphenyltrichloroethane （DDTs） in shellfish collected in study area from 2006 to 2007 were determined with gas chromatography （GC）. The concentration range of HCHs was （ND-12.13）×10^-3 mg/kg wet weight and averaged at 0.54×10^-3 mg/kg while the concentration of DDTs was in the range of （4.06-281.73） ×10^-3 mg/kg with a mean of 57.52×10^-3 mg/kg in the survey areas. The concentrations of DDTs in the shellfish were higher than HCHs＇, so that DDTs could be considered as typical organochlorine pollutants in the areas. The concentrations of DDTs in the shellfish were higher than HCHs＇, so that DDTs could be considered as typical organochlorines pollutants. The HCHs in all the shellfish conformed to the first level of criterion （0.02 mg/kg） of the Marion Biology Quality （GB 18421-2001）, and that of DDTs in most samples were beyond the first level （0.01 mg/kg） but conformed to the second level （0.10 mg/kg）. On average, α-HCH and δ-HCH occupied the most part of HCHs, while O,P＇-DDT and P,P＇-DDT occupied the most part of DDTs. The concentrations of organocholorine pesticides in shellfish samples varied in site and in species. The highest level occurred at the Shengsi （SS）, followed by Yangkougang （YKG）, Lvsi （LS）, Dongyuan （DY） and Beibayao （BBY）, low concentrations were observed at Changsha （CS）, Beidaodi （BDD）, and Gouqi （GQ）. The concentration of HCHs and DDTs in most sites decreased clearly from 2006 to 2007 except for YKG, DY, BDD, LYS, and SS. All of above results suggested that the study area was slightly affected by organochlorine pesticide, special by DDTs.

Gridded inventories of historical usage for selected organochlorine pesticides in Heilongjiang River Basin, China

The use of technical HCH （1, 2, 3, 4, 5, 6-hexachlorocyclohexane）, DDT （dichlorodiphenyltrichloroethane） and lindane in Heilongjiang River Basin （HRB） of China was studied. Between 1952 and 1984 the total usage in the HRB was 108900 t for technical HCH, and 4900 t for DDT, respectively, and the use of DDT due to dicofol application in the HRB was 220 t from 1984 to 2003. The usage of lindane in HRB was 109 t from 1991 to 2000. The results show that the highest technical HCH use （41800 t） in HRB was on maize, accounting for 38.3% of the total usage on all crops, followed by the use on wheat （28000 t, 25.7%） and on soybean （26600 t, 24.4%）. The highest DDT use （2300 t） was on soybean, accounting for 46.8% of the total usage on all crops, followed by the use on maize （1500 t, 31.3%） and on sorghum （600 t, 13.2%）. The major use of lindane was mainly on wheat. Gridded usage inventories of these three OCPs （organochlorine pesticides）, in HRB with a 1/6° latitude by 1/4° longitude resolution have been created by using different gridded cropland as surrogates. Some soil samples have also been collected in HRB. Data of usage and soil concentrations of 5： HCH in HRB match quite well to those in Shanghai region, and much higher soil concentration of 5： DDT in Shanghai region could be due to much heavier dicofol use in this region.

Distribution of persistent organochlorine pesticides in tissue/organ of silver carp (Hypophthalmichthys molitrix) from Guanting Reservoir, China

The concentration of organochlorine pesticides（OCPs） in tissues and organs of silver carp（Hypophthalmichthys mofitrix） from Guanting Reservoir were investigated to evaluate the pollution potential and distribution of OCPs. A total of 16 OCPs were measured and the concentrations were in the range of 1.61-69.01 ng/g wet weight（ww） for total OCPs, 0.16- 0.75 ng/g ww for HCB. 0.75 -26.80 ng/g ww for SHCH（sum of α-,β-, γ- and δ-HCH） and 0.68-35.94 ng/g ww for SDDT（ sum of p, p＇-DDE, p, p＇-DDD, o, p＇-DDT and p, p＇- DDT）. The mean concentrations of total OCPs, HCB, ∑HCH, and ∑DDT were 18.04, 0.96, 7.14 and 9.28 ng/g ww, respectively. Among the organochlorine pesticides, β-HCH and p, p＇-DDE were the most dominant compounds in tissue and organ with the average concentrations of 4.42 and 8.14 ng/g, respectively. The results obtained in this study show that the levels of 16 OCP residues found in silver carps are low and pose no threat to human health and wildlife fed upon them on the basis of existing related quality guidelines. However, recent input of lindane and DDT might still exist in the area investigated and further investigation should be carried on.

Isolation of Organochlorine Pesticide from Ginseng with Supercritical CO_2

The feasibility of removal of the organochlorine pesticides residues of hexachlorocyclohexane(BHC) from radix ginseng with supercritical CO2 was explored. Some factors, such as extraction pressure, extraction temperature, and kinds of co-solvents were investigated. The experimental results indicate that it is possible to reduce BHC residues in radix ginseng to the level of 0.1 × 10^-6 with supercritical CO2 in the presence of suitable amount of co-solvent, such as water.

Monitoring of Organochlorine Pesticide Residues──The GEMS/Food Program in China

This paper covers the monitoring activities of organochlorine (OCS) pesticide residues in the GEMS/Food program, which China took part in for the first time in 1992. The levels of HCH and DDT were determined in 355 samples of eight main varieties of food , taken from five provinces and cities. The results show that the positive rate of HCH is 69%, of which 99. 44 % is in accord with the National Standards of Food Hygiene of China. As to DDT, the two rates are 42 % and 100 % respectively. The daily intakes of HCH and DDT are 0. 22 mg/ kg.bw and 0. 54 mg/kg. bw respectively, which are far below their corresponding ADIs.Compared with those in 1970s, the OCS residues have decreased significantly. Therefore the monitored varieties of food are safe to people's health

Inferring of Organochlorine Pesticide Transmission under Atmospheric Circulation Impact

[ Objective] The study aims to infer the transmission of organochlorine pesticides under the influence of atmospheric circulation. [ Meth- od] A transmission profile of organochlorine pesticides was established in the region from the western margin of the Sichuan Basin to the western Si- chuan plateau, from which atmospheric particulate matter, atmospheric dry and wet deposition samples as well as corresponding soil samples were collected and analyzed. [ Result~ The study showed that HCHs content was the highest on the elevation boundaries of the study area, and,8-HCH content was the highest in the study area, indicating that there were no new HCHs input to the study area. In respect of HCHs content in the soil and atmospheric precipitation, it was significantly higher in low-lying areas than that of high-altitude areas. Besides, sources of organechlorine pesti- cides in high-altitude areas were mostly derived from atmospheric particulate matter and atmospheric dry deposition. A variety of factors affected the long-distance transmission of organochlorine pesticides, and the form of the atmospheric transport of organochlorine pesticides could be determined accurately based on the content of organochlorine pesticides in different media of each sample point. In different months, the sources of organechlo- rine pesticides in the atmospheric transmission varied with atmospheric circulation direction, so it could not be simply thought that organochlorine pesticides were transmitted from low-lying areas to high-altitude areas. Meanwhile, there was a transformation between the source and sink of or- ganochlorine pesticides in plateau areas because of atmospheric circulation changed. [ Condusionl The research could provide scientific references for the control of persistent organic pollutant diffusion and establishment of environmental protection measures. ds

Assessment of Organochlorine Pesticide Residues in Vegetable Samples from Some Agricultural Areas in Togo

The study was conducted to monitor the concentration of pesticide residues in three staple vegetables (tomato, cabbage, lettuce) collected from 12 prefectures belonging to 4 agro-ecological regions of Togo. A total of 150 samples of ripe tomato, cabbage and lettuce were collected from the study areas and analyzed for 20 OCPs (organochlorine pesticides) residues, which can be grouped into DDTs, Drins, Heptachlors, Chlordanes and HCHs. The data revealed that 100% of the analyzed vegetable samples were contaminated by one or more pesticide residues;83.32% and 100% were below the maximum residue limits (MRLs) set par European Union and FAO/WHO respectively whereas 16.68% were above the EU (MRLs) adopted values. Overall, cabbage contained the highest number of samples with pesticide residues above the MRLs followed by tomato, whilst none of lettuce samples contained pesticide residues above the MRLs. It is therefore proposed to perform continuous monitoring studies of pesticide residues in vegetables cultivated in Togo.

Residues of organochlorine pesticides in intertidal flat surface sediments from coastal zone of Jiangsu Province, China

Sixteen surface sediment samples were collected and analysed to evaluate the residues of organochlorine pesticides （OCPs） from intertidal fiat in Jiangsu Province. Overall, 22 OCPs were detected with total concentrations of OCPs ranging widely from 0.96 to 12.14 ng/g （dry wt）. Total hexachlorocyclohexane （HCH） and total dichlorodiphenyltrichloroethane （DDT） levels varied from 〈0.01 to 0.67 ng/g and from 0.23 to 4.85 ng/g, respectively. DDTs were the predominant compounds. The dominance of β-HCH indicated a history of HCH pollution. According to the ratios of （p,p＇-DDD＋p,p＇-DDE）/p,p＇DDT and o,p＇-DDT/p,p＇- DDT, new input of DDTs did not occur in most sites, and the main sources were historical usage of technical DDTs. OCPs such as dieldrin, endrin, p,p＇-DDD, and p,p＇-DDT exceeded the effects range low, showing adverse biological effects that would occasionally occur at some sites of the study area.

Analysis Method for Pesticide Residues in Biological Matrices： Gas Chromatography-mass Spectrometry

Pesticides have done a great service to human, but their use is not safe for public health. Apart from pesticides acute toxicity, their chronic toxicity can cause various problems for human health. The objective of this work was to validate a liquid-liquid extraction method, which allows a fairly reliable analysis of pesticides using gas chromatography-spectrometry mass （GC/MS） in toxicology laboratory at National Institute of hygiene, Rabat Morocco. The equipment required to perform these analyzes are the biological matrices （blood, gastric fluid）, in which the authors have doped the Organophosphorus pesticides such as Chlorpyrifos, Dichlorvos and Organochlorine pesticide： dichlorodiphenyltrichloroethane （DDT） and Heptachlor. After extracting the mixture with toluene, the supernatant was collected after centrifugation and concentrated in a small volume of 1.5 mL and then analyzed in GC/MS. After analyzing, the authors found that the yields of each pesticide in samples are significant; respectively they represented 73.4% of Chlorpyrifos, 70.8% of Dichlorvos, 47.8% of DDT and 71.6% of Heptachlor. The blood has a strong link with the most pesticides, where it＇s important to use the GC/MS to identify these products. The extraction with toluene was effective, especially to OP, but it＇s also sensitive to OC.

Organochlorine pesticides in sediments from Honghu Lake, China

The levels of 13 organochlorine pesticides （OCPs） in sediments of Honghu Lake were investigated in order to evaluate their potential pollution and risk. A total of 30 sediment samples from 15 sampling locations were collected in the lake during July, 2005. The total concentrations in top-sediment samples and sub-sediment samples ranged from 3.52 ng/g to 69.71 ng/g and 0.49 ng/g to 97.37 ng/g, respectively. The HCH isomers, DDT congeners, aldrin, trans-chlordane, cis-chlordane, heptachlor and endrin-ketone were significant in these samples. The concentrations of OCPs in the lakeshore sediments were higher than those sampled across the lake. Distribution of HCHs, DDTs and other OCPs were different, indicating their various contamination sources. Composition analysis in sediments indicated recent usage or discharge of lindane, dicofol into the lake.