Effect of pesticides on phosphorylation of tau protein,and its influence on Alzheimer’s disease

Alzheimer’s disease(AD)is a progressive and neurodegenerative illness which results in alterations in cognitive development.It is characterized by loss/dysfunction of cholinergic neurons,and formation of amyloid plaques,and formation of neurofibrillary tangles,among other changes,due to hyperphosphorylation of tau-protein.Exposure to pesticides in humans occurs frequently due to contact with contaminated food,water,or particles.Organochlorines,organophosphates,carbamates,pyrethroids and neonicotinoids are associated with the most diagnosed incidents of severe cognitive impairment.The aim of this study was to determine the effects of these pesticides on the phosphorylation of tau protein,and its cognitive implications in the development of AD.It was found that exposure to pesticides increased the phosphorylation of tau protein at sites Ser198,Ser199,Ser202,Thr205,Ser396 and Ser404.Contact with these chemicals altered the enzymatic activities of cyclin-dependent kinase 5 and glycogen synthase kinase 3 beta,and protein phosphatase-2A.Moreover,it altered the expression of the microtubule associated protein tau gene,and changed levels of intracellular calcium.These changes affected tau protein phosphorylation and neuroinflammation,and also increased oxidative stress.In addition,the exposed subjects had poor level of performance in tests that involved evaluation of novelty,as test on verbal,non-verbal,spatial memory,attention,and problem-solving skills.

Assessment of Pesticide Contamination in Cidade Dos Meninos, Rio de Janeiro, Brazil, Using Regional Screening Levels (RSL)

In the mid-20th century, the Malaria Institute in Brazil researched hexachlorocyclohexane (HCH), dichlorodiphenyltrichloroethane (DDT), and other organochlorines in Cidade dos Meninos, Rio de Janeiro, Brazil. After Malaria Institute closure, there was a 200-ton stock of chemicals compounds abandoned without any surveillance, which led to massive contamination of the nearby community by carcinogenic organochlorines. This article presents a new review of the Cidade dos Meninos’ case, analyzing the HCH and DDT contamination using a Haddon Matrix and Regional Screening Levels (RSL).

Status, Distribution and Ecological Risk Assessment of Persistent Toxic Substances in Suburban Agricultural Soils in Hohhot City, North China

A total of 52 soil samples of Hohhot City were collected and four heavy metals and eight organochlorine pesticides were analyzed. The results showed that Cr, Cu, Zn, and Pb in soil were in range of 20.54 - 48.15 mg/kg, 40.10 - 94.60 mg/kg, 35.14 - 110.48 mg/kg, 38.86g - 245.36 mg/kg, with a mean value of 37.24 mg/kg, 60.76 mg/kg, 80.49 mg/kg, and 145.99 mg/kg, respectively. The high degree of variation of Pb, Zn, and Cu, reflected that the heavy metals were mainly interfered by human factors. The content values of ∑DDTs ranged from 5.01 ng/g to 105.08 ng/g with a mean of 36.94 ng/g, while the ∑HCHs ranged from 6.52 ng/g to 48.65 ng/g with an average of 23.29 ng/g, indicated that DDTs were highly used than HCHs in the study area. The relatively low α-HCH/γ-HCH ratio and relatively high o,p’-DDT/p,p’-DDT ratio indicated the application of lindane and dicofol on regional agricultural soil. The mean Igeo values was Pb (2.9) > Cu (1.5) > Cr (-0.31) > Zn (-0.35), revealing that the soil in Hohhot City was not polluted by Cr and Zn (Igeo 0), moderate polluted by Cu (1 Igeo 2), moderate to heavy pollution by Pb (2 Igeo 3). The range of potential ecological risk index of metals was from 35.02 to 132.96, indicating low to moderate potential ecological risk. HCHs in all soil samples were less than 50 ng/g, which could be considered as unpolluted, while DDTs in several samples were between 50 and 500 ng/g, which could be regarded as having low pollution.

凝胶渗透色谱和气相色谱-质谱法测定动物食品中27种有机氯和15种拟除虫菊酯类农药残留量

A GC-MS method for the determination of 27 organochlorine pesticides and 15 Pyrethroid pesticides in animal food is established.The method was based on Gel Permeation chromatography combined with solid-phase extraction for sample preparation.Rapid qualitative and quantitative analyses was carried out by gas chromatography-mass spectrometry under the selective-ion monitoring mode.The experimental results showed that the correlation coefficients were better than 0.99,the recoveries for spiked standards were 70%-104%,the relative standard deviations were 2.1%-15.9%.

多壁纳米碳管固相萃取测定水中的有机氯农药

对于水样中的有机氯农药的净化方法主要是采用传统的液液分配的方法,缺点是溶剂使用量和前处理复杂.近年来固相萃取及固相微萃取等技术被应用到水样中的有机污染物的测定[1,2].如利用键合在硅胶上的非极性(C18,LC18等)或极性物质(LC-CN,LC-NH2)对水中有机物进行富集,用GDX或XAD自填的固相柱的报道也很多[3,4].……

气相色谱-负离子化学电离质谱法对咖啡中8种有机氯农药的检测

An efficient and selective analytical method for the determination of 8 organochlorines pesticides residues(α-666,β-666,γ-666,δ-666,op’-DDT,pp’-DDT,pp’-DDD,pp’-DDE) in coffee has been developed.The coffee samples were extracted with hexane-acetone(1 ∶1,by volume) according to a selective extraction step using accelerated solvent extraction(ASE),followed by a clean-up by gel permeation chromatography(GPC) and a column combined with Florisil and GCB.Identification and quantification were performed using gas chromatography with negative chemical ionization mass spectrometric detection(GC-NCI MS).The method detection limits varied between 0.002 and 0.069 ng/g.The calibration curves showed a good linearity for all OCPs(r≥0.999 5) under a concentration of 0.20-50.0 μg/L.When the spiked levels were 0.5 μg/L and 5 μg/L,the average recoveries were range of 94%-110% with RSD of 3.5%-10.6%.The method was accurate,sensitive and suitable for the analysis of pesticides.

Eco-Toxicological Approach as a Contribution to Integrated Water Management on Okpara Dam at Kpassa in Benin: Evaluation of Contamination of Fish and Surface Water by Organochlorine Pesticides

The paper explores the degree of pollution of organochlorine pesticides in fish and water in the dam at Kpassa on a tributary of Okpara River that is pumped by Benin National Water agency (SONEB) in supplying drinking water to supply the city of Parakou. Doing so, fourteen parameters of organochlorine are analyzed. Most of obtain organoclorine concentration in water and fish below is indicated critical values. However, DDT and endrine concentration in water is slightly above legal tolerable values. Hexachlorobenen and dieldrine concentrations are three times higher than legal limit value while aldrine is ten times higher. However, heptachlore is double concentrated in fishery while aldrine (endrine, dieldrine aldrine, lindane, hexachloro-benzene, DDT) is found in the dam fish and surface water three times concentrated than tolerated value. These levels of concentrations result from the intensification of organoclorine pesticide used in agriculture especially in cotton production. These are caused by the chemical application accumulated in soil and through the food value chain system. Therefore, it is very important to extract sediment from the reservoir by dredging in oder to renew the ecosystem of the dam. To persistently manage the basin water resources, it is imperatively important to observe a significant behaviour changed from all stakeholders.

Impact of Pesticides Contamination on Nutritional Values of Marinefishery from Karachi Coast of Arabian Sea

The present study explores the chemical and economic aspects of pesticide contamination of marinefishery in relation to nutritional values Marine Pollution of pesticides poses signify can tricks to the environment and non-target organisms ranging from beneficial marine micro organisms, to insects, seaweeds, fish, and mangroves at Karachi Coast. Fish typically contains good quality nutrition, particularly oily fish has maximum commercial values but contamination of fishery is the major problem caused by pesticides and PCBs pollution resulting in serious health hazards. A number of fish and shell fish samples were analyzed for determination of pesticides contamination due to marine environment pollution. It was found that most pesticides pose risk to humans, fishery or the environment because they are designed to kill or adversely affect living organisms. Quantitative analysis of pesticides and PCBs was performed using GC equipped with ECD and the FPD for organophosphorus and GC-MS. The arithmetic mean concentrations of each pesticide were calculated and statistical evaluation was done. Relationship of protein and pesticides level has been determined to determine impact of pesticide on protein content of each type of fish. There is a considerable difference found in the pesticides contents of each type of fishery, which reveals that environmental pollution status that attributes towards pesticides distribution.

Pesticide Biomonitoring in Florida Agricultural Workers

This descriptive study evaluates the blood serum levels of relevant pesticides in fern/ornamental and tomato agricultural workers in central and south Florida whose work activity is related to pesticide application or crop maintenance. The objectives of this study are to broadly evaluate pesticide absorption in agricultural workers, assess personal protective equipment (PPE) use and their potential relevance to pesticide absorption, and to evaluate the feasibility of using primary biomonitoring as a method of exposure assessment for long-term epidemiological investigations. Three rounds of sampling were conducted where 41 subjects provided serum samples analyzed for individual pesticides and responded to a survey regarding PPE use. Serum samples yielded quantifiable detections of DDE, Methiocarb, Malathion, Chlorpyrifos, and Endosulfan in select subjects. The personal protective equipment survey did not demonstrate association with positive serum samples. These results demonstrate that the evaluated workers are effectively protected against exposures known to result in acute toxicity. Biomonitoring for parent compounds and primary metabolites may have limited utility in long-term epidemiological studies to evaluate chronic toxicity where workers are exposed to a great diversity of workplace chemicals (fern/or- namental workers) compared to agricultural sectors where workplace chemical diversity is more limited (tomato workers).

Assessment of Lindane and Atrazine Residues in Maize Produced in Ghana Using Gas Chromatography-Electron Capture Detector (GC-ECD) and Gas Chromatography-Mass Spectrometry (GC-MS)

Maize is consumed by over 95% of the Ghanaian populace and the practice of using Atrazine and Lindane (an Organochlorine) pesticides in its production has raised concerns about potential adverse effects on human health and the environment. A field survey was conducted in this study to assess farmers’ knowledge of safe handling and use of these chemicals as well as toxicity awareness and symptoms among farmers and traders. Residues of these pesticides in maize samples as well as the potential health risk associated with exposure to them were also evaluated. Composite maize samples were collected for nine of ten regions in Ghana and analyzed. Data obtained from the field survey indicate that a large proportion of farmers are at risk of pesticide poisoning through occupational exposure. Over 80% of applicators do not apply safety precautions during pesticide mixing and application;resulting in considerable prevalence of pesticide related illnesses in the study area. Residues of Lindane and atrazine were below detection limits of 0.005 mg/kg and 0.010 mg/kg respectively;except in the Ashanti region where atrazine was 0.05 mg/kg which was within the EU-MRL of 0.1 mg/kg. However, minute concentrations of other Organochlorines (endrin—0.007 mg/kg;heptachlor—0.023 mg/kg;alpha-endosulfan—0.013 mg/kg) were found in maize samples from Brong Ahafo, eastern, central and upper west regions. Though endrin and alpha-endosulfan were below the EU-MRL of 0.01 mg/kg and 0.10 mg/kg respectively, heptachlor was slightly above the EU-MRL of 0.01 mg/kg. The estimated dose for all these pesticides however does not pose direct hazard to human health although present in the maize samples since the values were lower than toxic thresholds and reference doses. However, due to the unsafe application practices by applicators, there exists a potential risk for systemic and carcinogenic health effects by these chemicals in the study area.

Determination of Pesticide Residues in Soils of Cotton Farming Areas in Togo

The main cash crop in Togo is cotton, with about 70% of agricultural exports. This crop is very dependent on the use of chemical inputs, in particular pesticides. Pesticides used in cotton farming in Togo include organochlorines, triazines, organophosphates and pyrethroids. We conducted a study on the impact of these pesticide use, in particular organochlorines and triazines, on cotton farming soils. We chose the Plateaux region (southern Togo) as the study area because of its high cotton production. Analysis was carried out on crop soil samples at the 0 - 20 cm horizon. Several pesticide residues were found: simazine (0.051 to 0.103 μg/Kg soil);atrazine (0.149 to 0.197 μg/Kg soil);lindane (0.259 to 0.672 μg/Kg soil);β-endosulfan (1.37 to 5.727 μg/Kg soil);dieldrin (0.063 to 1.16 μg/Kg soil);endrin (0.512 μg/Kg soil), Heptachlor (0.489 to 1.243 μg/Kg soil);Heptachlor epoxide (0.928 to 1.633 μg/Kg soil);[2,4'DDT] (0.257 μg/Kg soil);[4,4'DDE] (0.262 μg/Kg soil). These results show pesticide contamination of cotton farming soils.

Contamination by Organochlorine Pesticides in the Estuaries of Southeast China

Persistent organic pollutants(POPs) such as organochlorine pesticides are of global concern due to their widespread occurrence and persistence. This paper reports recent research studying the distribution and fate of organochlorine pesticides in the Jiulong River, the Minjiang River and the Pearl River estuaries in Southeast China. Eighteen organochlorine pesticides were extracted from water, pore water and sediment samples, followed by analysis by GC ECD. The results showed that the contamination levels were similar in these three estuaries. The levels of the total organochlorine pesticides in porewater were significantly higher than those in surface water, due to the high affinity of these hydrophobic compounds for sediment phase. Among the hexachlorocyclohexane(HCH) compounds, β HCH was found to be the most important isomer. The analysis of 1,1,1 trichloro 2,2 bis chlorophenyl ethane(DDT) and its metabolites showed that 1,1 dichloro 2[ o chlorophenyl] 2[ p chlorophenyl] ethylene(DDE) was dominant in the group.

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 of chlordanes (CHLs), heptachlors (HEPTs), and endosulfans comprised 0.51%, 1.05%, and 0.79% of fifteen OCPs, respectively. The preliminary pollution assessment indicated that DDTs have caused high OCPs levels in some schools. Source identification showed that HCHs in soils were originated from an old mixed source of technical HCHs and lindane. And DDTs were mainly from mixed use of technical DDTs and dicofol containing DDT impurities. According to GB15618-1995 (guidelines of Chinese environmental quality standards for soils), HCHs and DDTs levels might be categorized as little and low polluting pesticides. This study indicated that the environmental quality of college school yards with large green land were not as good as was expected and there existed potential exposure risk of college population to OCPs.

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(B1–B19) 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.

Distribution of organochlorine compounds in water, porewater and sediments in Xiamen Harbour

The Concentrations of 18 organochlorine pesticides and 12 polychlorinated biphenyls (PCBs) in water, porewater and sediments from the Xiamen Harbour were analyzed quantitatively. It shows that, the levels of all organochlorine insecticides varied from 6. 60 to 19 .6 ng/dm3 (in water), 11. 9-78. 5 ng/dm3(in porewater) and not detected (ND) - 0. 58 ng/g dry weight (in sediments), and those of total DDTs were in the range ND - 0. 06 ng/g dry weight. Concentrations of PCBs and in- secticides in porewater were higher than in surface water, due to the higher affinity of these hydrophobic compound for sedimentary phase than to water. It implies there would be a potential flux of pollutants from sediments to overlying water. Compared with the concentrations of these pollutants measured in the Xiamen Harbour in 1993, it is one to several magnitude order lower, which suggests their inputs have been decreased in recent years and possible degradation of these compounds. The levels of these pollutants were also compared with other estuaries.

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.

Polychlorinated Biphenyls and Chlorinated Pesticides in Sediments along the Semi-Closed Areas of Alexandria, Egypt

The residues of 19 EPA-organochlorine pollutants were analyzed in sediments collected from 49 different locations along the semi-closed areas of Alexandria, Egypt. The pollutants studied were 7 individual polychlorinatedbiphenyl (PCB) congeners, α,β,γ-hexachlorocyclohexane (HCHs), cyclodienes (aldrin, endrin, dieldrin) and dichlorodiphenyltrichloroethanes (DDTs) (o,p-DDE, p,p-DDE, o,p-DDD, p,p-DDD, o,p-DDT, p,p-DDT). The concentration of total DDTs ranged between ND and 123.76 ng.g-1 (dry wt) whereas the concentration of PCBs, HCHs and cyclodienes ranged from ND to 192.24 ng.g-1;ND to 20.78 ng.g-1 and ND to 8.04 ng.g-1 dry wt, respectively. The average total organic carbon (TOC) percent was varied from 0.04 to 7.65%.

有机氯农药DDT对秋茄萌生的影响

有机氯农药ＤＤＴ对秋茄萌生的影响黄建斌，林鹏（生物学系环境科学研究中心）红树林是热带、亚热带河口海岸的木本植物群落￣［１］．它具有较强的生活力，对河口海区的污染物有一定净化能力，红树植物生长在有机机氯农药污染的水体中它将在生长上受到什么影响，尚未见过...

Synthetic Detergents (Surfactants) and Organochlorine Pesticide Signatures in Surface Water and Groundwater of Greater Kolkata, India

An assessment on the concentration of surfactants and pesticides of chlorinated hydrocarbon group in surface and groundwater, is made from Greater Kolkata located in the Western Ganga Delta, one of the largest urban agglomerate in Asia. Concentration of both anionic synthetic detergents and organochlorine pesticide resi-dues analysed from 54 and 19 sampling stations covering groundwater and surface water sources respec-tively, are generally found to be within the tolerance limit for human consumption. The concentration of synthetic detergent ranges from 0.084 to 0.425mg/l. Residues of organochlorine pesticides are analysed from different sources like tanks, lakes, rivers and groundwater. Lindane (0.01-0.43μg/l) and DDT (0.03-0.65 μg/l) are the most widely detected pesticide residues. Howerer, the two have not exceeded the limits for drinking anywhere. High value of aldrin and dieldrin (0.9μg/l) is obtained in the river Hugli at Barakpur-Seoraphuli, 20 km north of Kolkata. Likewise high value of Heptachloreis detected in a canal water sample at Palta (0.05 μg/l), a suburban area. Seasonally, the pesticide concentration in surface water is maximum during winter due to their higher application and minimum during monsoon. In groundwater, however, this relationship is reverse due to higher infiltration of surface water during monsoon.