Organic Chlorinated Pesticides Research Articles

ÇEVRESEL KİRLETİCİLER VE PLASENTAL TRANSPORTERLAR: PCB ile SLC VE ABCB1 ÖRNEĞİ

Aim: Due to the environmental usage, these substances can be applied to the placental blood industry due to the shelves and the deteriorated membrane transportation. It is intended that their environmental effects can be influenced by these transport proteins. Materials and Methods: Within the scope of the study, in the placenta of the owner and endotheliochorial dog; Good by analysis of 28 good (PCB, PBDE, PAH and Organic chlorinated pesticides); The expression profile of the placental whole genome was investigated by RNAseq, evaluated in silico (mole clamping) and in vitro (SLC and ABCB1 mRNA analysis in the placental cell line HTR8/SVneo treated with PCB 101, PCB118). Results: PCB101 826.4μg/kg in one of the 60 samples tested; In 23 samples, PCB118 was found to be between 0.14 and 41.9μg/kg. In 55 samples in the sequence analysis in bioinformatics, PCB was found in 742 genes between positive and negative (p

Quantitative analysis and contamination profiles of PCBs, OCPs, and PAHs in black-tailed gull eggs in the Republic of Korea.

The simultaneous determination of 8 polychlorinated biphenyls (PCBs), 23 organic chlorine pesticides (OCPs), and 35 polycyclic aromatic hydrocarbons (PAHs) in black-tailed gull eggs was described using ultrasound-assisted extraction and gas chromatography-tandem mass spectrometry (GC-MS/MS). The ranges of the lower limits of detection for PCBs, OCPs, and PAHs were 0.006-0.029, 0.01-0.10, and 0.01-0.20μgkg-1, respectively. The intraday precision was in the range of 0.650-12.9% and the intraday accuracy was in the range of 86.6-113%. When the proposed method was used to analyze the target compounds in gull eggs collected from six sites in the Republic of Korea, the analytical results demonstrated concentration ranges of 113.32-394.07µgkg-1 for total PCBs, 422.92-1082.09µgkg-1 for total OCPs, and 134.50-231.27µgkg-1 for total PAHs in the samples. The PCA results for PAHs and OCPs were well differentiated by sampling site, whereas those for PCBs differed little by sampling site. There were more pyrogenic PAHs in the West Sea and the South Sea with many industrial areas than in the East Sea with few industrial areas. Differences in the OCP patterns of samples from the West Sea close to China were considered to be related to the use of DDT in China until recently. PCBs were accumulated in the samples regardless of region, so there was no significant difference in the PCB patterns between the samples obtained from the three Seas.

Comprehensive Risk Assessment of Organchlorine Pesticides (Ocps) Based on a Large Region-Scale Characterization of Ocps in Freshwater Sediments and Multiple Aquatic Foods in China

Comprehensive Risk Assessment of Organchlorine Pesticides (Ocps) Based on a Large Region-Scale Characterization of Ocps in Freshwater Sediments and Multiple Aquatic Foods in China

Time Trend of Persistent Organic Pollutants and Metals in Greenlandic Inuit during 1994-2015.

Persistent organic pollutants (POPs), including polychlorinated biphenyls (PCBs), organchlorine pesticides and perfluoroalkylated substances (PFASs) and heavy metals bioaccumulate in the marine food chain in the Arctic regions, and thus, the Greenlandic population has a higher body burden due to relatively high intake of marine mammals. We assessed the temporal trend for POPs, including PCB 153; 1,1-dichloro−2,2-bis (p-chlorophenyl)-ethylene (p,p’-DDE); oxychlordane; six PFASs; mercury; lead and selenium in Inuit from Ilulissat, Nuuk, and across Greenland (including thirteen towns/districts), from 1994 to 2015. Data showed a significant annual decrease of 6.85–8.61% for PCB153, 6.67–8.61% for p,p’-DDE, 6.11–9.52% for oxychlordane, 5.92–6.76% for mercury and 6.48–9.43% for lead in Inuit women from Nuuk, Ilulissat, and across thirteen Greenlandic districts. The blood selenium level of all Greenlandic women increased 1.01% annually, while the trend direction was negative for Nuuk women. A similar pattern was seen for men across Greenland, with a yearly decrease of 11.3% for PCB 153, 8.61% for p,p’-DDE, 15.6% for oxychlordane, 13.1% for mercury and 12.2% for lead. Perfluorooctane sulfonate, perfluorohexane sulfonate and perfluorooctanoic acid significantly decreased 5.82–11.7% annually for both women and men across Greenland. For perfluorononanoic acid, perfluorodecanoic acid and perfluoroundecanoic acid, we observed an increasing trend for women across Greenland. In conclusion, there was a decreasing trend of the regulated POPs and metals but a potential increasing trend of the nonregulated PFASs in the Greenlandic population between 1994 and 2015. The continuing biomonitoring of contaminants of concern is important to protect the Arctic population heath.

Determination of pesticide residues in wolfberry using QuEChERS-gas chromatography-tandem mass spectrometry

A method based on QuEChERS-gas chromatography-tandem mass spectrometry (GC-MS/MS) was established for the determination of 20 pesticide residues in wolfberry. The samples were extracted with acetonitrile. The extract was purified with PSA (primary secondary amine), GCB (graphite carbon black) and C18 to suppress the matrix in wolfberry. The analytical results showed that the calibration curves for the 20 pesticides obtained by GC-MS/MS were linear in the range of 5-500 μg/L, with the correlation coefficients higher than 0.99. The recoveries ranged from 70.02% to 110.78% with relative standard deviations (RSDs) ranging from 2.05% to 9.53%. This method has the advantages of being time-saving, convenient and sensitive. The proposed method can simultaneously detect organic phosphorus and organic chlorine pesticides residues with a good performance in terms of qualitative and quantitative detection.

MEASURING THE ECONOMIC IMPACT AND HEALTH RISKS OF PESTICIDE RESIDUES IN POTATOES AND GRAPES CROPS

The research aims to study pesticide residues on potatoes and grapes to improve and develop the management of integrated control programs, reduce economic losses and do not harm human health, To achieve this, the research relied on the results of the sample data collected from some local markets of some governorates of the Republic, Pesticide residues were evaluated and potential risks assessed for food containing pesticide residues exceeding the maximum allowable limit for each crop. The most important results of the study: - The results of the analysis of the sample of the study, which included 79 samples, potato yield 44 samples, grapes 35 samples, showed that the number of samples free of pesticide residues 31 samples represents 39.24% of the total samples, The number of samples contaminated with pesticide residues was 48 samples representing 60.76% of the total samples. The number of samples exceeding the maximum allowable residues (MRLs) of 16 pesticides represented 33.3% of the total samples contaminated with pesticide residues. - The study also showed the emergence of some organic chlorine pesticides banned since 1972 in some potato crop samples in Assiut governorate. - The results of the study show the presence of some pesticides that exceeded the limit allowed daily intake (EDI), according to what the Food and Agriculture Organization (FAO), and the World Health Organization (WHO): Carbofuran with a risk index of about 1128%, or more than the daily intake of about 1028%, followed by the pesticide dezynone with a risk index of about 168% more than the daily intake of 68%. Recommendations:To tighten control on pesticides that are not allowed to be used and to track smuggled pesticides to prevent their circulation in local markets. 2- Raising awareness and training for farmers in the Upper Egypt governorates to rationalize the use of pesticides and methods of applying them with optimum economic efficiency to reduce pollution and the absence of pesticide residues beyond the permissible limits. 3- Continued pesticide residue monitoring programs in all food products to provide and update a database through which future strategies for pest control and consumer protection can be implemented through random exposure to pesticides. 4- Directing the producers of the grapes to rationalize the use of pesticides because they use large amounts and different types of pesticides, which leads to pollution of the crop and thus causing significant economic losses.

The temporal changes of the concentration level of typical toxic organics in the river sediments around Beijing

In this study, the current situation of five types of toxic organics and endocrine disrupters in the sediments of rivers around Beijing, i.e., polycyclic aromatic hydrocarbons (PAHs), phthalic acid esters (PAEs), organic chlorinated pesticides (OCPs), estrogens (Es), and bisphenol A (BPA), which included 56 contaminants, was analyzed and compared with that registered by the historical literatures. The ecological risks were also assessed. The total concentration of PAHs, PAEs, OCPs, Es, and BPA ranged from 232.5 ng·g–1 to 5429.7 ng·g–1, 2047.2 ng·g–1 to 18051.5 ng·g–1, 4.5 ng·g–1 to 11.7 ng·g–1, 18.1 ng·g–1 to 105.2 ng·g–1, and 36.3 ng·g–1 to 69.6 ng·g–1, respectively. Among these five types of organic compounds, the concentration levels of PAHs and OCPs have decreased significantly in the last ten years, while those of PAEs and Es had an upward trend compared with the previous studies. BPA still remained at a moderately high level, as it was ten years ago. The risks of the PAEs in all of the sample sites, and fluoranthene, benzo[a]anthrene, and benzo[a]pyrene in the Wenyu River sediment, were relatively high. These results supplemented the database of toxic organics’ concentration levels in the sediments of Beijing rivers.

Organochlorine pesticides in soils from the Issyk-Kul region in the western Tian Shan Mountains, Kyrgyzstan: Implication for spatial distribution, source apportionment and ecological risk assessment

As organchlorine pesticides (OCPs) may be an ecologic threat to mountain environments due to their tendency to deposit and accumulate in mountain regions undergoing long-range air transport, OCPs were analyzed in soils collected from an intermontane basin of the western Tian Shan Mountains, which is the UNESCO protected natural reserve of Issyk-Kul. Total OCP concentrations in the Issyk-Kul region ranged from 4.63 to 414 ng/g dw, of which two extraordinary high OCP concentrations (414 ng/g dw and 213 ng/g dw, respectively) influenced by an abandoned dumping site and urban sewage, respectively, were found. Principal component analysis (PCA) and correlation analysis inferred that the OCP inputs in the east of the Issyk-Kul region were mainly from local endogenous sources, and exogenous input via LRAT processes were prominent in the west and south. Additionally, the isomeric and parent substance/metabolite ratios revealed most pesticides accumulated in this region were from old usage, while DDTs had fresh input because of possibly illegal regional application and a slow degradation from the dumping site. Furthermore, ecological risk assessment revealed that no frequently adverse ecological effects were observed in the Issyk-Kul region, but potential risks on neighbouring organisms induced by p,p’-DDT and γ-HCH in dumping site and urban sewage should be considered when devising an efficient management plan to prevent secondary pollution.

Occurrence and Ecological Risk Assessment of Typical Persistent Organic Pollutants in Baiyangdian Lake

A comprehensive survey of the pollution characteristics of persistent organic pollutants (POPs) in the surface water and surface sediment of Baiyangdian Lake was carried out. The survey showed that:① The concentrations of the polycyclic aromatic hydrocarbons(PAHs), organic chlorine pesticides (OCPs), and polybrominated diphenyl ethers (PBDEs) in the surface water of Baiyangdian Lake were 71.32-228.27 ng·L-1, 2.62-6.13 ng·L-1, and 0-6.5 ng·L-1, respectively, and those in the surface sediment were 163.20-861.43 ng·g-1, 2.25-6.07 ng·g-1, and 230.96-1224.13 pg·g-1, respectively. On comparison with historical data, the concentrations of PAHs and OCPs in both the surface water and surface sediment were found to be decreasing, while compared with the domestic and foreign lakes, the concentration of PBDEs in the surface sediment was at a low level. ② The main source of PAHs, both in the surface water and surface sediment in Baiyangdian Lake, originated from fuel discharge and combustion sources. HCHs compose the main part of OCPs in both the surface water (93.76%) and surface sediment (63.10%). In the surface water body, HCHs mainly originated from the degradation of industrial HCHs; in some sites HCHs originated from atmospheric long-distance transmission and the usage of Lindane, while DDTs originated from historical residues. In surface sediment, HCHs mainly originated from the usage of new Lindane, with little industrial HCHs, and DDTs mainly originated from historical residues, while new DDTs may have been used in some sites. BDE-2 (65.80%) composed the main part of PBEDs in the surface water, and it mainly originated from atmospheric long-distance transmission and degradation of high brominated diphenyl ethers; BDE-209 (63.82%) constituted the main part of PBDEs in the surface sediment, and it mainly originated from the commercial Deca-BDEs.③ Ecological Risk Assessment show that there was no obvious ecological risks in Baiyangdian Lake, but in some sites POPs may cause ecological risks; these sites should be monitored more frequently.

Pesticides and Risk of Obesity and Diabetes

Objective: This study seeks to examine current research evidence and literature linking pesticide exposure with obesity and diabetes. Study Design and Setting: The review presented here summarizes research studies regarding the association between pesticides and obesity, including diabetes and the metabolic syndrome. Published literature was reviewed between 1996 and 2015. Studies highlighting investigations examining the potential association between pesticides and the outcomes of interest were included. Results: Although this is not a meta-analysis, a summary of research finding that showed the most studies investigating an association between pesticides and obesity and/or diabetes are presented. Overall, many of the studies demonstrate a positive correlation between pesticide exposure and key measures of these two health conditions (Body Mass Index, Weight, Glycated Hemoglobin (Hemoglobin A1c), Blood Glucose Levels, And Serum Insulin Levels). Likewise, inherent complexities of pesticide chemicals and the multifactorial nature of obesity and diabetes further limit study conclusions. Conclusions: Literature supports a potential positive association between pesticide exposure and obesity and/or diabetes. However, mechanisms accounting for such an association have yet to be defined, and notable gaps exist in assessing the extent to which an association may exist. In this regard, evidence supports further research to better define these areas. Keywords: Diabetes; Metabolic Syndrome; Obesity; Pesticides Abbreviations: OP : Organophosphate pesticides OC : Organ chlorine pesticides POPs : Persistent organic pollutants BMI : Body Mass Index MB : Methanobacteriales DDT : Dichloro diphenyl trichloroethane DDE : Dichloro diphenyl dichloroethylene PCBs : Polychlorinated biphenyls AHS : Agricultural Health Study

Pesticide use in the wheat-maize double cropping systems of the North China Plain: Assessment, field study, and implications

In the North China Plain (NCP), rising inputs of pesticides have intensified the environmental impact of farming activities in recent decades by contributing to surface water and groundwater contamination. In response to this, the Chinese government imposed stricter regulations on pesticide approval and application, and better monitoring strategies are being developed. However, sufficient and well-directed research on the accumulation and impact of different pesticides is needed for informed decision-making.In this study, current pesticide use, and recent and current research on water contamination by pesticides in the NCP are reviewed and assessed. Additionally, a small-scale field study was performed to determine if residuals from currently-used pesticides in the NCP can be detected in surface water, and in connected shallow groundwater. The contaminants of interest were commonly used pesticides on winter wheat-summer maize fields (the dominant cropping system in the NCP), such as 2,4-D and atrazine. Sampling took place in May, July, and October 2013; and March 2014.Results from our literature research showed that sampling is biased towards surface water monitoring. Furthermore, most studies focus on organic chlorinated pesticides (OCPs) like the isomers of dichlorodiphenyltrichloroethane (DDT) and hexachlorocyclohexane (HCH), which were banned in China in 1983. However, currently-used herbicides like 2,4-D and atrazine were detected in river water and groundwater in all samplings of our field study. The highest concentrations of 2,4-D and atrazine were found in the river water, ranging up to 3.00 and 0.96μg/L, respectively.The monitoring of banned compounds was found to be important because several studies indicate that they are still accumulating in the environment and/or are still illegally in use. However, supported by our own data, we find that the monitoring in groundwater and surface water of currently permitted pesticides in China needs equal attention, and should therefore be increased.

The evolution of pollution profile and health risk assessment for three groups SVOCs pollutants along with Beijiang River, China.

Three important groups of semi-volatile organic compounds (SVOCs), polycyclic aromatic hydrocarbons (PAHs), organic chlorinated pesticides (OCPs) and phthalate esters (PAEs), were produced by various human activities and entered the water body. In this study, the pollution profiles of three species including 16 PAHs, 20 OCPs and 15 PAEs in water along the Beijiang River, China were investigated. The concentrations of Σ16PAHs in the dissolved and particulate phases were obtained as 69-1.5×102 ng L-1 and 2.3×103-8.6×104 ngg-1, respectively. The levels of Σ20OCPs were 23-66ng L-1 (dissolved phase) and 19-1.7×103 ngg-1 (particulate phase). Nevertheless, higher levels of PAEs were found both in the dissolved and particulate phases due to abuse use of plastic products. Furthermore, non-cancer and cancer risks caused by these SVOCs through the ingestion absorption and dermal absorption were also assessed. There was no non-cancer risk existed through two kinds of exposure of them at current levels, whereas certain cancer risk existed through dermal absorption of PAHs in the particulate phase in some sampling sites. The results will show scientific insights into the evaluation of the status of combined pollution in river basins, and the determination of strategies for incident control and pollutant remediation.

Dichloro-Diphenyl-Trichloroethane (DDT) and Endosulfan in Sediments of Sabancuy Lagoon, Campeche, Mexico

DDT and Endosulfan are persistent organic compounds which have been prohibited and their use has been limited in agricultural activities due to their toxicity, persistence and bioaccumulation potential. The use of DDT in fumigation campaigns against endemic diseases transmitted by vectors of malaria and dengue was prohibited in Carmen Island, Campeche, Mexico since 1995. In the surroundings of Sabancuy Lagoon, many and diverse agricultural activities are carried out and it is a common practice to use organ-chlorine pesticides as endosulfan. In order to know the levels of these compounds in this area, a sediment sampling campaign was carried out in ten sampling points randomly located within the Sabancuy Lagoon, Campeche and considering one reference sampling point located 2 km away from Sabancuy Lagoon within the Mexican Gulf. Three metabolites were identified in sediments samples belonging to DDT’s family: (4,4’-DDD; 4,4’-DDE; 4,4’- DDT) and Endosulfan’s family (Endosulfan I, Endosulfan II y Endosulfan sulfate). Higher concentrations in DDT’s family were found for 4,4’-DDD, followed by 4,4’-DDE and 4,4’-DDT. Endosulfan’s family, showed the following order for concentrations: Endosulfan II > Endosulfan I > Endosulfan sulfate. Mean concentration for S-DDT and S-Endosulfan in Sabancuy Lagoon sediments was twice higher than those found in other studies carried out in Términos Lagoon, Campeche, Mexico in 2002.

Influences of binding to dissolved organic matter on hydrophobic organic compounds in a multi-contaminant system: Coefficients, mechanisms and ecological risks

The complexation flocculation (CF) method was successfully employed to identify binding coefficients (Kdoc) of specific organic contaminants to dissolved organic matter (DOM, often indicated by dissolved organic carbon, DOC) in a multi-contaminant hydrophobic organic contaminant (HOC) system. Kdoc values were obtained for most of the evaluated 33 HOCs, indicating the feasibility and applicability of the CF method in a multi-contaminant system. Significant positive correlations were observed between binding coefficients and octanol–water partition coefficients (Kow) for organic halogen compounds, such as polybrominated diphenyl ethers (PBDEs) (R2 = 0.95, p < 0.05) and organic chlorine pesticides (OCPs) (methoxychlor excluded, R2 = 0.82, p < 0.05). The positive correlations identified between the lgKdoc and lgBCF (bioconcentration factor) for PBDEs and OCPs, as well as the negative correlation observed for polycyclic aromatic hydrocarbons (PAHs), indicated that different binding or partition mechanisms between PAHs and organic halogen compounds exist. These differences further result in discriminative competition partitions of HOCs between DOM and organisms. Assuming that only freely dissolved HOCs are bioconcentrative, the results of DOM-influenced bioconcentration factor (BCFDOM) and DOM-influenced lowest observed effect level (LOELDOM) indicate that the ecological risk of HOCs is decreased by DOM.

A passive sampler based on solid phase microextraction (SPME) for sediment-associated organic pollutants: Comparing freely-dissolved concentration with bioaccumulation

The elevated occurrence of hydrophobic organic chemicals (HOCs) such as polycyclic aromatic hydrocarbons (PAH), polychlorinated biphenyls (PCBs) and legacy organchlorine pesticides (e.g. chlordane and DDT) in estuarine sediments continues to poses challenges for maintaining the health of aquatic ecosystems. Current efforts to develop and apply protective, science-based sediment quality regulations for impaired waterbodies are hampered by non-concordance between model predictions and measured bioaccumulation and toxicity. A passive sampler incorporating commercially available solid phase microextraction (SPME) fibers was employed in lab and field studies to measure the freely dissolved concentration of target HOCs (Cfree) and determine its suitability as a proxy for bioaccumulation. SPME deduced Cfree for organochlorines was highly correlated with tissue concentrations (Cb) of Macoma and Nereis spp. co-exposed in laboratory microcosms containing both spiked and naturally contaminated sediments. This positive association was also observed in situ for endemic bivalves, where SPME samplers were deployed for up to 1month at an estuarine field site. The concordance between Cb and Cfree for PAH was more variable, in part due to likely biotransformation by model invertebrates. These results indicate that SPME passive samplers can serve as a proxy for bioaccumulation of sediment-associated organochlorines in both lab and field studies, reducing the uncertainty associated with model predictions that do not adequately account for differential bioavailability.

Evaluation of Liquid–Liquid Extraction Methods for Determining the Levels of Lipids and Organochlorine Pollutants in Human Milk

Organic chlorine pesticides and polychlorinated biphenyls are organic pollutants that are stored in the adipose tissues of humans. The concentrations of those pollutants in human milk have previously been utilized as a biomarker for monitoring the body burden of lipophilic pollutants in humans. Liquid–liquid extraction methods have been applied to lipids, chlorinated pesticides, and polychlorinated biphenyls from breast milk. In this study, the effectiveness of four extraction methods, which have been widely used to isolate fats and organic pollutants from milk, were compared. The organic solvents included hexane, hexane/acetone (2:1, v/v), ethanol/ethyl ether/hexane (2:3:4, v/v), and methanol/chloroform (1:1, v/v). These results demonstrated that hexane yields the lowest extraction recoveries for lipids (approximately 21.3%) and analytes (approximately 50%). The other three organic solvents demonstrated better performance in extracting the target compounds, with the ethanol/ethyl ether/hexane system showing the optimum efficiency. The optimized system was employed to determine the analytes in human milk.

Distribution, possible sources, and health risk assessment of SVOC pollution in small streams in Pearl River Delta, China.

The pollution levels of typical semivolatile organic compounds (SVOCs) consisting of 15 polycyclic aromatic hydrocarbons (PAHs), 20 organic chlorinated pesticides (OCPs), and 15 phthalate esters (PAEs) were investigated in small rivers running through the flourishing cities in Pearl River Delta region, China. The concentrations of ∑15PAHs were 2.0-48 ng/L and 29-1.2 × 10(3) ng/g in the water and sediment samples, respectively. The ∑20OCPs were 6.6-57 ng/L and 9.3-6.0 × 10(2) ng/g in the water and sediment samples, respectively. The concentrations of ∑15PAEs were much higher both in the water and sediments. The partition process of the detected SVOCs between the water and sediment did not reach the equilibrium state at most of the sites when sampling. The combustion of petroleum products and coal was the major source of the detected PAHs. The OCPs were mainly historical residue, whereas the new inputs of dichlorodiphenyltrichloroethane (DDT), chlordane, and endosulfan were possible at several sites. The industrial and domestic sewage were the major source for the PAEs; storm water runoff accelerated the input of PAEs. No chronic risk of the SVOCs was identified by a health risk assessment through daily water consumption, except for the ∑20OCPs that might cause cancer at several sites. Nevertheless, the integrated health risk of the SVOCs should not be neglected and need intensive investigations.

Identification of two interference peaks during dioxin analysis for biological samples

Two interference peaks which generally appeared in company with 13C labeled 2,3,7,8-tetrachlorodibenzofuran (13C12-2,3,7,8-TCDF) in the same ion channel during dioxin analysis for biological samples were identified using high resolution gas chromatography/high resolution mass spectrometry (HRGC/HRMS) and high resolution gas chromatography/low resolution mass spectrometry (HRGC/LRMS). It was firstly inferred that the interference peaks should be the two isomers of dichlorodiphenyldichloroethylene (DDE), which was a breakdown product of dichlorodiphenyltrichloroethane (DDT), one of the typical organic chlorine pesticides (OCPs). Thereafter, the standard solution of DDE including o,p'-DDE and p,p'-DDE was analyzed for confirmation. By evaluation of the peak separation in HRGC/HRMS, comparison of the GC retention times and ion abundance ratios of the two interference peaks in real samples with the two DDE isomers in standard solution, the interference peaks were finally confirmed as o,p'-DDE and p,p'-DDE in sequence on a DB-5MS column. This study provided valuable information for accurate identification of dioxin compounds during the biological sample analysis.

Transcriptional responses, metabolic activity and mouthpart deformities in natural populations of chironomus riparius larvae exposed to environmental pollutants

Biomarkers are an important tool in laboratory assays that link exposure or effect of specific toxicants to key molecular and cellular events, but they have not been widely used in invertebrate populations exposed to complex mixtures of environmental contaminants in their natural habitats. The present study focused on a battery of biomarkers and their comparative analysis in natural populations of the benthic larvae of Chironomus riparius (Diptera), sampled in three differentially polluted rivers (the Con, Sar, and Louro in Galicia, Spain). In our study, some parameters were identified, such as hsp70 gene activity, GST enzymatic activity, total glycogen content and mouthpart deformities, which showed significant differences among populations from the three rivers that differed in the levels and types of sedimentary contaminants analyzed (metals, organic-chlorine pesticides, alkylphenols, pharmaceutical, and personal care products). In contrast to these sensitive biomarkers, other parameters showed no significant differences (hsc70 gene, EcR gene, P450 gene, RNA:DNA ratio, total protein content), and were stable even when comparing field and nonexposed laboratory populations. The hsp70 gene seems to be particularly sensitive to conditions of pollutant exposure, while its constitutive counterpart hsc70 showed invariable expression, suggesting that the hsc70/hsp70 ratio may be a potential indicator of polluted environments. Although further studies are required to understand the correlation between molecular responses and the ecological effects of pollutants on natural populations, the results provide new data about the biological responses to multiple-stressor environments. This field study adds new molecular endpoints, including gene expression, as suitable tools that, complementing other ecotoxicological parameters, may help to improve the methodologies of freshwater monitoring under the increasing burden of xenobiotics.

Assessment of halogenated POPs and PAHs in three cities in the Yangtze River Delta using high-volume samplers

The objective of this study was to quantify organic chlorinated pesticides, polychlorinated biphenyls (PCBs), polybrominated diphenyl ethers (PBDEs) and polycyclic aromatic hydrocarbons (PAHs) in air samples collected from July 2009 to April 2010 in Suzhou, Wuxi and Nantong in the Yangtze River Delta (YRD) and to identify potential sources of these pollutants during the period. Gas- and particle-phase concentrations of these species were determined using gas chromatography–mass spectrometry on samples collected using high volume samplers. Phenanthrene, fluoranthene, hexachlorobenzene (HCB), p,p′-DDE, tri-CB (#18), tri-CB (#28) and deca-BDE (#209) were the most abundant compounds in the YRD. Average concentrations of these pollutants in Suzhou, Wuxi and Nantong, respectively, were 88.4, 105 and 69.5ng/m3 for PAHs, 162, 237 and 136pg/m3 for HCB, 35.7, 41.7 and 34.7pg/m3 for hexachlorocyclohexane, 131, 83.1 and 229pg/m3 for DDTs, 63.4, 52.4 and 31.7pg/m3 for chlordanes, 80.5, 51.8 and 65.1pg/m3 for PCBs, 30.4, 32.0 and 54.6pg/m3 for PBDEs (tri- to hepta-BDE) and 882, 807 and 1200pg/m3 for deca-BDE (#209). Concentrations of the emerging persistent organic pollutant, deca-BDE (#209), in the three cities were greater than those of other countries. Massive production and/or the use of commercialized deca-BDE (#209) may occur in metropolitan areas and development zones in the YRD.