Atmospheric monitoring of organochlorine pesticides across some West African countries

Most African countries have ratified the Stockholm Convention on persistent organic pollutants (POPs) and are expected to reduce emissions of POPs such as organochlorine pesticides (OCPs) to the atmosphere. Emerging evidence, however, suggests that there are contemporary sources of OCPs in African countries despite the global ban on these products. This study investigated the atmospheric contamination from OCPs in four West African countries—Togo, Benin, Nigeria, and Cameroon—to ascertain the emission levels of OCPs and the characteristic signatures of contamination. Polyurethane foam (PUF) disk passive air samplers (PAS) were deployed in each country for ca. 55 days in 2012 and analyzed for 25 OCPs. Hexachlorocyclohexanes (HCHs) and DDTs constituted the highest burden of atmospheric OCPs in the target countries, at average concentrations of 441 pg m^?3 (range 23–2718) and 403 pg m^?3 (range 91–1880), respectively. Mirex had the lowest concentration, ranged between 0.1 and 3.3 pg m^?3. The concentration of OCPs in rainy season was higher than in dry season in Cameroon, and presupposed inputs from agriculture during the rainy season. The concentrations of ∑25 OCPs in each country were in the following order: Cameroon > Nigeria > Benin > Togo. There was significant evidence, based on chemical signatures of the contamination that DDT, aldrin, chlordane, and endosulfan were recently applied at certain sites in the respective countries.     

Monitoring of organochlorine pesticides residues in green mussels (Perna viridis) from the coastal area of Thailand

The utilization of organochlorine pesticides for pest control chemical has been of great interest on residue contamination from biological organisms in the environment. Green mussel (Perna viridis) samples were monitored as bioindicators for assessment of the water quality in coastal waters along the Gulf of Thailand. Thirty-six samples were collected from 12 stations during 1997-1999 and analysed for 26 organochlorine pesticide compounds. This paper focuses on the contamination of organochlorine pesticide residues in green mussel (P. viridis) during 1997-1999. The limit of detection of all organochlorine pesticides compounds was at the range of 0.1-8.3 ng g(-1) wet weight and recovery 75-95%. The concentration of organochlorine pesticides residues in green mussel was lower than the maximum residue limit for aquatic animals as recommended by the Ministry of Public Health of Thailand. The trend of organochlorine pesticide residue contamination in this area decreased from 1989 to 1999.     

Atmospheric deposition of organochlorine contaminants to Galveston Bay,Texas

Atmospheric monitoring of PCBs and chlorinated pesticides (e.g., HCHs, chlordanes, and DDTs) in Galveston Bay was conducted at Seabrook, Texas. Air and wet deposition samples were collected from 2 February 1995 and continued through 6 August 1996. Vapor total PCB (tPCB) concentrations in air ranged from 0.21 to 4.78 ng m⁻³ with a dominance of tri-chlorinated PCBs. Dissolved tPCBs in rain ranged from 0.08 to 3.34 ng l⁻¹, with tetra-chlorinated PCBs predominating. The predominant isomers found in air and rain were α- and γ-HCH, α- and γ-chlordanes, 4,4′-DDT, and dieldrin. The concentrations of PCBs and pesticides in the air and rain revealed no clear seasonal trend. Elevated levels of PCBs in the air occurred when temperatures were high and wind came from urban and industrialized areas (S, SW, NW, and W of the site). Concentrations of HCHs were elevated in April, May, and October, perhaps due to local and/or regional applications of γ-HCH (lindane). Other pesticides showed no notable temporal variation. When winds originated from the Gulf of Mexico (southeasterly), lower concentrations of organochlorines were detected in the air. The direct deposition rate (wet+dry) of PCBs to Galveston Bay (6.40 μg m⁻² yr⁻¹) was significantly higher than that of pesticides by a factor of 5–10. The net flux from gas exchange estimated for PCBs was from Galveston Bay water to the atmosphere (78 μg m⁻² yr⁻¹). Gas exchange of PCBs from bay water to the atmosphere was the dominant flux.     

Nationwide monitoring of polychlorinated biphenyls and organochlorine pesticides in sediments from coastal environment of Korea

To assess the organochlorine contamination in the Korean marine environment, a nationwide monitoring study was conducted. A total of 138 surface sediments, covering the whole Korean coast, were collected and analyzed. Organochlorine compounds (OCs) were widely distributed in the Korean coastal environment, with PCB and DDT contamination being particularly prevalent. The overall concentrations of PCBs, DDTs, HCHs, CHLs, and HCB in surface sediments were in the range of 0.088-199ngg(-1) (median value: 1.56ngg(-1)), 0.006-135ngg(-1) (0.68ngg(-1)), not detected (ND)-5.46ngg(-1) (0.32ngg(-1)), ND-3.26ngg(-1) (0.14ngg(-1)), and ND-2.59ngg(-1) (0.05ngg(-1)), respectively. The southeastern coast was found to be highly contaminated. Overall contamination status of Korean coastal sediments with regard to OCs is lower than that of USA. With the exception of highly industrialized sites, Korean coastal areas in general showed similar OC concentrations to those of other Asian countries. There was a significant correlation between distributions of most organochlorine contaminants with each other. OC contamination is closely related to shipping and industrial activities. Of the 7 sites categorized as highly polluted, 4 are in a harbor zone. Adverse effects to benthic communities are expected at the levels of OC contamination observed from harbor and industrial areas.     

Atmospheric deposition of organochlorines (PCBs and pesticides) in northern France

Bulk deposition measurements were made in northern France for a number of organochlorines (PCBs, HCB, pp'DDE, alpha-HCH and gamma-HCH) over a 1-y period, at urban, semi-rural, rural and forest sites located in accordance with prevailing wind direction. The west-east rise of PCB bulk deposition (average annual values as sigma 7) ranged from 12.2 to 46.8 ng l(-1) and showed the anthropogenic influence arising from towns, industries, storage areas and landfills over continental areas. The values were maximal at the urban site 3, Paris (122 ng l(-1)) and were still high at the eastern site 6, Abreschviller near landfills (62 ng l(-1)). Also, the highest annual deposits were found at sites 3 and 6 (Paris and Abreschviller), 38.6 and 47.3 microgm-2, respectively, i.e. 3.6 and 4 times higher than the western site value: Pleumeur. A temporal trend was observed, at the urban site where a rise occurred (up to 441 ng l(-1)) in March and April. PCB distribution according to the chlorination degree displayed high proportions of 3 Cl and 4 Cl congeners, particularly in the forest area. Annual gamma-hexachlorocyclohexane (gamma-HCH) concentration values at sites 1 (Ouessant) and 2 (Pleumeur) were close to the background noise (1.7 ng l(-1)). At the agricultural (4) and the urban (3) sites, values were maximal (19.2 and 15.9 ng l(-1)) with peaks in spring and autumn. At Pleumeur, without any local input, negative correlations were found between PCB/temperature (r = -0.503, p < 0.05), HCB/temperature ( r = -0.549, p < 0.01) and gamma-HCH/temperature ( r = -0.675, p < 0.01). A clear influence of south-west winds upon the magnitude of PCB fluxes throughout the sites was noticed. Whereas there was no global decrease of PCB contamination since 1986, the general trend of gamma-HCH total deposits was a 10-time fall, as a result of the restricting legislation in use.     

Atmospheric trace elements in Antarctic prehistoric ice collected at a coastal ablation area

We present here the results of the analysis of 22 elements or compounds in a large block of prehistoric blue ice more than 12000 years old collected at a coastal ablation area in east Antarctica. Successive veneer layers chiselled in sequence from the exterior to the center have been analysed separately in order to determine the contamination characteristics of the block.Concentrations measured in the central parts probably represent the original concentrations in the prehistoric blue ice, thus giving estimates of pre-man natural reference, levels of these elements or compounds in Antarctic precipitations. For the enriched elements Cd, Cu, Zn, Au, Se and for SO₄, concentrations are shown not to differ significantly from those presently observed in surface snow in the central plateau areas from which the ice is thought to originate. This suggests that the remote polar regions of the southern hemisphere are still little affected by global pollution for these elements and for S compounds. For crustal derived elements, concentrations in prehistoric ice are found to be significantly higher than those in present day snow; this confirms that crustal flux to the Antarctic continent was higher during Wisconsin times than now.     

Atmospheric deposition of polycyclic aromatic hydrocarbons near New England coastal waters

Wet and dry deposition of polycyclic aromatic hydrocarbons (PAHs) was measured at Nahant, Massachusetts, a peninsula jutting into Massachusetts Bay and Wolf Neck, a peninsula jutting into Casco Bay, Maine. Wet deposition (rain and snow) was collected in a funnel which drains into a shielded, temperature controlled receiving bottle. Dry deposition of gaseous and particulate PAHs was collected onto an exposed water surface. PAHs were analyzed by solid phase extraction and gas chromatography-mass spectrometry. Sixteen PAH species were analyzed, ranging from acenaphthylene to coronene. The mean wet deposition rate of the sum of the 16 species is 720 ng m⁻² cm⁻¹ precipitation at Nahant, and 831 ng m⁻² cm⁻¹ precipitation at Wolf Neck. Wet deposition is attributed to regional PAH emitting sources. Storm patterns appear to bring somewhat higher wet deposition of PAHs to Wolf Neck than to Nahant. The mean dry deposition rate is 95 ng m⁻² h⁻¹ at Nahant and 9.3 ng m⁻² h⁻¹ at Wolf Neck. The large difference is attributed to the fact that Nahant is close to the urban-industrial metropolitan Boston area and Logan International Airport, whereas Wolf Neck has no major PAH-emitting sources nearby. Individual measurements have an error bracket of ±30%. The Chemical Mass Balance model was used to apportion the dry deposition to source categories. At Nahant, nine samples gave valid statistical attributes with a mean apportionment: jet exhaust 35%, gasoline fueled vehicles 32%, diesel fueled vehicles 17%, wood combustion 13%, others 3%. At Wolf Neck, six samples yielded a mean apportionment: jet exhaust 30%, gasoline vehicles 28%, diesel vehicles 18%, wood combustion 16%, others 8%. There is a considerable variation between the samples. The apportionment is greatly dependent on the quality and selection of the model inputs, i.e. source signatures, which for PAHs are questionable.     

Chiral organochlorine pesticides in the atmosphere

We measured the enantiomeric fractions (EF) of various organochlorine pesticides in air samples from Indiana, Arkansas, and Louisiana collected in 2002–2003. Enantiomeric fractions for o,p′-DDD are reported here for the first time, and they suggest preferential depletion of one enantiomer over the other, with a mean value of 0.44. For the chlordanes, the EFs followed the same trends as reported in previous studies. EF values for trans-chlordane (TC) were slightly below 0.5, and values for cis-chlordane (CC) were slightly above 0.5. For cis-heptachlor epoxide (HEPX), the EF values averaged 0.65, indicating a clear preferential depletion of the (−)-enantiomer. For TC and CC, no clear distinction could be made between the values measured among the three sites, suggesting that it is not possible to use these EF values as “source signatures”. For HEPX, the Indiana site had significantly higher EF values than did the Arkansas site; this difference may reflect differences in the historic use of heptachlor in these two regions.     

Concentration of organochlorine pesticides in wine corks

Wine corks were extracted and analyzed for 23 organochlorine pesticides, including alpha-, beta-, and gamma-hexachlorocyclohexanes (HCH), hexachlorobenzene, DDT, DDE and DDD, chlordane, endosulfan, dieldrin, aldrin, and endrin. This was done to investigate the occurrence, concentrations, composition profiles, and possible sources of organochlorine contamination. All groups of compounds were detected in every sample investigated, with the exception of aldrin and endrin. The total concentrations of organochlorine compounds in all samples ranged from 75-120 ng/g lipid, and for most compounds, the concentrations of organochlorines in cork were consistent with published data for other plant tissues. Differences in the relative abundances of the various classes of organochlorine pesticides were substantial and were probably due to differences in the pesticide usage practices of the various regions in which the cork producing trees were grown.     

Residues of organochlorine pesticides in Alabama soils

A survey was made of 36 Alabama agricultural soils to assess residues of formerly used organochlorine pesticides. Compounds determined comprised alpha- and gamma-hexachlorocyclohexane, heptachlor, heptachlor-exo-epoxide, trans- and cis-chlordane, trans-nonachlor, dieldrin, toxaphene, DDT and DDE. Concentrations varied by several orders of magnitude among farms and appeared to be log-normally distributed. Highest concentrations (ng g(-1) dry soil, arithmetic means) were found for toxaphene (285+/-390) and DDTs (p,p'-DDE, 22.7+/-21.4; p,p'-DDT, 24.6+/-30.5; o,p'-DDT, 4.00+/-5.86; p,p'-DDD, 2.40+/-2.41) which were once heavily used in the southern USA. Pesticide residues were not proportional to soil organic carbon content indicating that residue concentrations were a reflection of pesticide application history and dissipation rates rather than air-soil equilibrium. Mean ratios of DDT/DDE in six regions of the state ranged from 0.39 to 1.5, and compound ratios for chlordanes and toxaphene were different from those in the technical mixtures.     

Atmospheric deposition of polybrominated diphenyl ethers (PBDEs) in coastal areas in Korea

Atmospheric bulk samples were collected monthly, for one year, from urban, suburban, and rural sites located in the coastal areas of Korea, for the assessment of depositional fluxes and seasonal variations in atmospheric concentrations of PBDEs. Twenty individual PBDE congeners were found in atmospheric samples, and their depositional fluxes varied from 10.1 to 89.0 microg/m2/year. The highest depositional fluxes were found in two urbanized areas, with a strong urban-rural gradient. The relationship between PBDE and particulate depositional fluxes showed significant correlation for all locations, which suggested the association of PBDEs to particulate phase. Deca-BDE (BDE 209) was the predominant congener (>93%) in all deposition samples, which is consistent with a high consumption of deca-BDE for the flame-retardant market in Korea. Seasonal variability was observed in PBDE concentrations for the two urban sites, whereas no seasonal trend was found for either the suburban or the rural location.     

Residues of organochlorine pesticides in fishes in Sudan

Abstract

Cotton‐producing areas of the Centrol Sudan, bordered by the Blue and the White Nile, have been subjected to repeated applications of pesticides. This region is irrigated by a series of canals, the Gezira canals, which hold large amounts of fresh water. Lake Nubia at the Sudan‐Egypt border is another important fresh water reservoir and fisheries ground. Fish from both the Gezira and Lake Nubia showed elevated concentrations of pesticides, suggesting that continued pesticides application would endanger the equatic fauna of this region and the proposed fresh water fishery.     

北京城市雨水、树冠水和地表径流中有机氯农药的污染特征

对北京降雨过程中雨水、树冠水、地表径流等介质中有机氯农药(OCPs)的污染特征进行了研究,研究的污染物包括六氯苯(HCB)、六六六(HCH)和滴滴涕(DDT)。结果显示,在雨水、树冠水和地表径流中,HCH含量最高(几何平均浓度分别为11.1、21.6和25.1 ng/L),其次是HCB(几何平均浓度分别为3.71、3.54和5.91 ng/L)和DDT(几何平均浓度分别为2.64、4.66和10.6 ng/L)。对地表径流样品中所测的OCPs组分浓度与径流水质参数和气象参数的相关分析显示,所测各OCPs组分浓度与pH呈显著负相关,与径流的溶解性有机碳含量呈显著正相关,降雨量和雨前晴天数对不同组分OCPs的影响并不完全相同。平均贡献率的计算表明,雨水是城市地表径流中OCPs的一个重要来源,树冠水的贡献也不可忽视。     

Residues of organochlorine pesticides in Hong Kong soils

It was short of research on the organochlorine pesticides (OCPs) residues in the soils of Hong Kong. Sixty-six representative soil samples were collected from the 46 sites covering five types of land uses in Hong Kong. Hexachlorohexanes (HCH) and 7 Stockholm Convention OCPs were analyzed by gas chromatograph (GC) equipped with a Nickel 63 electronic capture detector (muECD). The results presented that HCH and 5 Stockholm Convention pesticides were detected in Hong Kong soils although the detectable ratio varies to a great extent. The concentration sequence of the five detectable OCPs was HCH > dichlorodiphenyltrichloroethane (DDT) > hexachlorobenzene (HCB) approximately = Endrin > alpha-endosulfan. Among the OCPs and their homologues or isomers, beta-HCH and p,p'-DDE were the two predominant substances according to the concentrations and detectable ratios, concentrations of which in soils were averagely 6.12 microg kg(-1) and 0.41 microg kg(-1) respectively. Soil horizon samples of 0-10 cm, 10-30 cm and >30 cm depth were selected from nine soil profiles to demonstrate the depth distributions of DDT and HCH in soil profiles. Concentrations of HCH tended to increase gradually from the topsoil to bottom layer while the lowest concentration of DDT is usually found in the subsoil (10-30 cm) in most sampling sites. In addition, close correlations of pH(KCl) and total organic carbon (TOC) with HCH indicated an effect on the residues of HCH caused by these two soils properties, but such relationships were not found with DDT or other OCPs.     

Atmospheric PCBs and organochlorine pesticides in Birmingham,UK: concentrations,sources, temporal and seasonal trends

Concentrations of individual PCBs and DDT, DDE, α- and γ-HCH were recorded in 62 air samples of 24 h duration taken every 1–2 weeks at an urban location in Birmingham, UK between April 1999 and July 2000. Concentrations of PCBs 31/28, 52, 49, 47, 105, 149, 153, 138/164, 174, and 180 were significantly lower (p<0.05) than those recorded at the same site in 1997–1998. While DDT concentrations and DDT:DDE ratios were much lower than those recorded in southern England in 1992–1993; no such decline was observed in concentrations of α- and γ-HCH, or the α:γ-HCH ratio. These data are consistent with declining European usage of DDT, but continuing UK use of γ-HCH, and overseas use and subsequent atmospheric transport of “technical” HCH. γ-HCH concentrations displayed two non-temperature dependent peaks in spring and late summer/early autumn, consistent with agricultural use patterns. Multiple linear regression analysis was used to elucidate the relative influence of temperature, wind direction and a variety of other meteorological variables on atmospheric concentrations of PCBs. When all samples were considered, concentrations of most PCB congeners were influenced by a combination of reciprocal temperature, wind direction, and wind speed. Plotting the ratio of the Beta weightings for the regression coefficients for reciprocal temperature and sine (or cosine) of wind direction against chlorine number, revealed a general increase in the relative influence of temperature compared to wind direction with increasing chlorine number. However, when the 31 samples for which the wind speed <4.4 m s⁻¹ were analysed; only temperature and atmospheric relative humidity were influential for most congeners. This absence of influence of wind direction under relatively calm atmospheric conditions, suggests that it is medium-to-long range transport rather than local sources that exerts the greatest influence on PCB concentrations at our site.     

舟山近岸海域贝类中有机氯农药残留水平及人体健康风险评估

于2012年的7月在舟山群岛新区的海域采集贝类样本,测定了其中的有机氯农药残留量,并进行了人体健康风险评估和安全食用量推算。结果表明,采集的5种贝类样本中,六六六(BHCs)的各组分均未被检出,而滴滴涕(DDTs)在各种样本中均有检出,其中僧帽牡蛎和部分縊蛏样本中DDTs总量超过《海洋生物质量标准》(GB 18421—2001)一类标准(10μg/kg);健康风险评估结果显示,贝类样本中α-BHC、β-BHC、γ-BHC、p,p’-滴滴伊(p,p’-DDE)、p,p’-滴滴滴(p,p’-DDD)、p,p’-DDT的总致癌风险指数均低于10-4,致癌风险均在可接受的安全范围,α-BHC、β-BHC、γ-BHC、p,p’-DDE的总接触风险指数均小于1,接触风险指数未超过危害剂量参考值,人体食用舟山近岸海域的贝类是安全的;按可接受的致癌风险指数进行评估,人体的贝类安全消费量为9.8~138.0g/(kg·d)(按体重计,下同),而按可接受的接触风险指数进行评估,人体的贝类安全消费量在24.6~235.0g/(kg·d)。     

Distribution and ecological risk of organochlorine pesticides and polychlorinated biphenyls in sediments from the Mediterranean coastal environment of Egypt

Organochlorine contamination in the Mediterranean coastal environment of Egypt was assessed based on 26 surface sediments samples collected from several locations on the Egyptian coast, including harbors, coastal lakes, bays, and estuaries. The distribution and potential ecological risk of contaminants is described. Organochlorine compounds (OCs) were widely distributed in the coastal environment of Egypt. Concentrations of PCBs, DDTs, and chloropyrifos ranged from 0.29 to 377 ng g⁻¹ dw, 0.07 to 81.5 ng g⁻¹ dw, and below the detection limit (DL) to 288 ng g⁻¹ dw, respectively. Other organochlorinated pesticides (OCP) studied were 1–2 orders of magnitude lower. OCP and PCBs had higher concentrations at Burullus Lake, Abu Qir Bay, Alexandria Eastern Harbor, and El Max Bay compared to other sites. OCP and PCB contamination is higher in the vicinity of possible input sources such as shipping, industrial activities and urban areas. PCB congener profiles indicated they were derived from more than one commercially available mixture. The ratios of commercial chlordane and heptachlor metabolites indicate historical usage; however, DDT and HCHs inputs at several locations appear to be from recent usage. The concentrations of PCBs and DDTs are similar to those observed in sediments from coastal areas of the Mediterranean Sea. Ecotoxicological risk from DDTs and PCBs is greatest in Abu Qir Bay, Alexandria Harbor, and El-Max Bay.     

Removal of organochlorine pesticides from lindane production wastes by electrochemical oxidation

This study is focused on the effective removal of recalcitrant pollutants hexaclorocyclohexanes (HCHs, isomers α, β, γ, and δ) and chlorobenzenes (CBs) present in a real groundwater coming from a landfill of an old lindane factory. Groundwater is characterized by a total organic carbon (TOC) content of 9 mg L^?1, pH₀?=?7, conductivity?=?3.7 mS cm^?1, high salt concentration (SO₄^2?, HCO₃^?, Cl^?), and ferrous iron in solution. The experiments were performed using a BDD anode and a carbon felt (CF) cathode at the natural groundwater pH and without addition of supporting electrolyte. The complete depletion of the four HCH isomers and a mineralization degree of 90% were reached at 4-h electrolysis with a current intensity of 400 mA, the residual TOC (0.8 mg L^?1) corresponding mainly to formic acid. A parallel series reaction pathway was proposed: HCHs and CBs are transformed into chlorinated and hydroxylated intermediates that are rapidly oxidized to non-toxic carboxylic acids and/or mineralized, leading to a rapid decrease in solution pH.     

Accumulation of organochlorine pesticides by semipermeable membrane devices using composite complex

Semipermeable membrane devices (SPMDs) were developed for passive in situ monitoring of organochlorine pesticides (OCPs) in aqueous solution in both laboratory and field (Pearl River Delta, China) studies. The device consisted of a thin film of neutral lipid triolein, enclosed in thin-walled tubing made of composite cellulose acetate membrane (CA) supported by linear low density polyethylene (LLDPE) (CAPE). Results from the laboratory and field application indicated that triolein-CAPE (TCAPE) could quickly and efficiently accumulate hydrophobic OCPs in water and uptake equilibrium could reached within 20h in the laboratory. Some mathematical relationships of TCAPE-water partition coefficient (logK(sw)), triolein-water partition coefficient (logK(tw)) and octanol-water partition coefficient (logK(ow)) were developed under the laboratory conditions. A good correlation of accumulation in TCAPE with r(2) values ranging from 0.55 to 0.86 for individual OCPs (n=8) and an excellent correlation of logK(sw) and logK(ow) was also obtained under the field conditions. The average OCPs concentration in the surface water could be estimated by measuring OCPs concentration in the device under the field conditions.     

Distribution of organochlorine pesticides in soils from South Korea

Soil samples were collected from rice growing and industrial areas in South Korea and analysed for organochlorine pesticide content using gas chromatography with electron capture detection. The soils were monitored for the presence of 18 organochlorine pesticides. The main pesticides found were gamma- and delta-hexachlorocyclohexane, heptachlor epoxide and dieldrin. The range of concentrations, for each compound, was respectively, 0.17-0.94, 0.77-2.97, 1.38-48.0 and 0.32-0.49 ng/g soil. The highest values were found in soil obtained from rice fields indicating that, although the use of organochlorine pesticides has been discontinued since 1980, substantial concentrations of residues particularly the oxidised form of heptachlor remain in the soil.