Distribution, bioaccumulation, and health risk assessment of organochlorines across the riverine ecosystem of Punjab Province, Pakistan.

This study was designed to assess the distribution of organochlorines (OCs) in fish species, their spatio-temporal variations, bioaccumulation potential, and associated human health risks via dietary intake. The levels of twenty-three organochlorine pesticides (OCPs) and thirty-five polychlorinated biphenyls (PCBs) were analyzed in six fish species collected from the riverine ecosystem of Punjab Province, Pakistan. The results indicated that the mean levels of Σ23OCPs were 74.1 ng/g ww and 184 ng/g ww, and for Σ35PCBs the levels were 38.8 ng/g ww and 74.8 ng/g ww in herbivorous and carnivorous fish species, respectively. The most abundant contaminants in all fish species were DDTs (65%) and HCHs (14%) among OCPs and heavier PCB congeners (62%) among PCBs. As for dioxin-like PCBs, the WHO toxic equivalency values (ng TEQ/g ww) were in the range of 0.21 (Cyprinus Carpio) to 2.38 (Rita Rita), exceeding the maximum allowable limit of 0.004 ng TEQ/g, ww by the European Commission. Spatio-temporal analysis indicated relatively higher OC levels in winter season with elevated concentrations in fish samples from industrial zone. The bioconcentration factor (L/kg) values ranged from 723 to 2773 for PCBs and 315 to 923 for OCPs in all fish species, with higher levels were reported in carnivorous species. The human health risk assessment at both 50th and 95th percentiles revealed the absence of any significant non-carcinogenic risk as calculated HR was less than 1. However, the critical carcinogenic risk was found to be associated for most of the contaminants, signifying the dietary exposure to OCPs and PCBs might pose the public health concern.

Toxicokinetic Modeling of the Transfer of Non-Dioxin-like Polychlorinated Biphenyls (ndl-PCBs) from Feed and Soil into Laying Hens and Their Eggs.

Non-dioxin-like polychlorinated biphenyls (ndl-PCBs) are a subclass of persistent bioaccumulative pollutants able to enter the food chain. Toxicokinetic models for the transfer of the six ndl-PCB congeners (PCBs 28, 52, 101, 138, 153, and 180) from contaminated feed and soil into chicken eggs and meat are presented. Three independent controlled feeding study datasets were used to estimate the model parameters and four studies for evaluating the model performance. The yolk deposition of ndl-PCBs is modeled in a novel way that mimics the physiology of yolk growth and development, resulting in improved prediction of the experimental data without introducing an ad hoc time delay between ovulation and oviposition. Using the models, the highest level of 2.4 µg/kg dry matter (DM) was calculated for the sum of ndl-PCBs in laying hen feed to ensure that the current maximum levels in meat and eggs (40 ng/g fat) will not be exceeded. It is also shown how this highest level in feed should be adapted in case soil, in addition to feed, is also a source of ndl-PCBs for free-range chickens.

Brominated and chlorinated contaminants in food (PCDD/Fs, PCBs, PBDD/Fs PBDEs): Simultaneous determination and occurrence in Italian produce.

Validated methodology for the simultaneous determination of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs), polychlorinated biphenyls (PCBs), polybrominated dibenzo-p-dioxins and dibenzofurans (PBDD/Fs) and polybrominated diphenyl ethers (PBDEs) in foods of animal origin is presented. Method performance indicators were equivalent or better than those required for the control of EU regulated (EU, 2017/644) PCDD/F and PCB congeners in these foods, and for risk assessment through dietary intake. The method uses a high (>90%) proportion of 13Carbon-labelled surrogates for internal standardisation combined with high resolution mass spectrometry that allow accurate quantitation, and this was confirmed by multiple successful participations in proficiency testing for PCDD/Fs, PCBs and PBDEs in food. The same validation and method performance requirements as used for PCDD/Fs were followed for PBDD/Fs. The analysis of a range of food samples (eggs, milk, fish, shellfish, pork, beef and poultry), showed the occurrence of all four classes of contaminants at varying concentration ranges. In general, PCBs were the most prominent contaminant, both, in terms of dioxin-like toxicity, as well as in the occurrence of non-dioxin-like congeners, an observation that concurs with those made in other studies on Italian foods. The levels of PCDD/F and PCB occurrence are consistent with a gradual decline in contamination as reported by some other similar studies. Although all the determined contaminants were detected in the sampled foods, there was poor correlation between the occurrences of the brominated and chlorinated contaminants, and between PBDEs and PBDD/Fs, but better associations were observed between the occurrences of the chlorinated contaminants.

Unraveling Congener-Specific Transfer of Non-Dioxin-Like Polychlorinated Biphenyls (ndl-PCBs) from Feed into Chicken Meat.

Non-dioxin-like polychlorinated biphenyls (ndl-PCBs) are a subclass of persistent bioaccumulative pollutants able to enter the food chain. We investigated the transfer of ndl-PCBs from contaminated feed into meat and liver of fattening chickens. A total of 48 chicks were divided into five treatment and one control groups. Treated animals were fed with contaminated diets (11.7 ± 0.4 µg/kg sum of indicator ndl-PCBs; 88% dry matter (DM)) before slaughter for different subperiods of time: 16, 23, 28, 32, and 36 days for groups 1-5, respectively. One day after the end of each subperiod, three animals per group were slaughtered to determine the congener-specific ndl-PCB content. All remaining animals were fed the control feed until slaughter on day 37 to probe depuration. We used these data to generate congener-specific physiologically based toxicokinetic (PBTK) models for indicator ndl-PCBs. The models show that PCBs 28, 138, 153, and 180 form a more slowly eliminated cluster (with an observed transfer rate into meat over 74% and observed half-lives over 8.7 days) than PCBs 52 and 101 (with a transfer rate under 13% and half-lives under 2.6 days). Our simulations show that ndl-PCB levels in feed lower than 3.9 (long 56-day) or 4.4 µg/kg (short 37-day fattening period) would be necessary to ensure the current maximum level in muscle meat (fat basis), according to EU Regulations 1881/2006 and 1259/2011. The PBTK models are made available in the Python and Food Safety Knowledge Exchange formats.

Health risks and source identification of dietary exposure to indicator polychlorinated biphenyls (PCBs) in Lanzhou, China.

Polychlorinated biphenyls (PCBs) are widely present in multiple environmental media even long after the phaseout, posing a health risk to the general population. Dietary intake is the major exposure route of PCBs; however, information is limited regarding PCBs in food that people directly consume. This study aims to measure personal exposure to indicator PCBs, evaluate the health risks, and identify their sources in a typical metropolitan city in China. Multi-day food samples were collected from 21 subjects in Lanzhou, Gansu Province, in two seasons using the duplicate plate method. Samples were extracted and analyzed for seven indicator PCBs using gas chromatography/mass spectrometry. Average daily doses (ADDs) of ∑7PCBs were estimated using Monte Carlo analysis with food intake information. Results show that PCB-118 and PCB-180 were the major congeners in food samples with average concentrations of 1.42 and 1.11 ng/g, respectively. The average (± SD) ADD of ∑7PCBs was 26.47 ± 22.10 ng/kg day among adults aged 18-69 years and displayed small variation across age groups. Comparing with the chronic RfD of 7 ng/kg day, 67% of people had their ADDs exceeding this threshold. The median cancer risk was 5.52 × 10-5, and 51% of residents had risks exceeding the action level of 10-4. The principal component analysis identified waste incineration, gasoline engine production, and leakage of #1 PCBs as the major PCBs sources. In conclusion, a large portion of Lanzhou residents has high non-cancer and cancer risks from dietary exposure to PCBs, which warrants control actions targeting these major sources.

PCDD/PCDFs and PCBs in the irrigation water in Egypt: levels, patterns, and potential sources.

The contamination levels of PCDD/PCDFs in irrigation water are the most rarely studied throughout the world. The major problem in Egypt is the lack of studies and statistics about these contaminants of POPs in irrigation water. Therefore, this study is the first comprehensive report to elucidate the estimation and sources of PCDD/PCDFs and PCBs in irrigation water from Egypt and rare for worldwide may provide a reference to future studies of POPs compounds in irrigation water of Egypt. A total of 24 irrigated water samples were collected from different irrigation canals which are adjacent to industrial areas from six Egyptian governorates (Bani Swef, El-Giza, El-Sharkeya, El-Menoufeya, El-Gharbeya, and Alexandria). The study shows that irrigation water canals were contaminated with low levels of PCDDs/PCDFs, which were 0.95 pgWHO-TEQ/l, and the total of PCDD/PCDFs and dl-PCBs were 2.06 pgWHO-TEQ/l with contamination ranging between 0.88 to 2.97 pgWHO-TEQ/l while the levels of indicator PCBs were 18.52 ng/l and ranged between 0.39 to 165.6 ng/l. The most predominant dioxins congeners were HpCDD, OCDD, HpCDF, and OCDF while for dl-PCBs were PCB105 and PCB118, and for ndl-PCBs was PCB138. The areas with recent urbanization and industrialization were more contaminated with PCBs than the unindustrialized area. Lightly to moderately chlorinated congeners dominated the PCB profiles. The major sources for these contaminants were fire bricks followed by textile industries closer to the located sampling sites. The detected pattern was found to be similar to the patterns reported in the air by other studies. Although the concentrations of the studied POPs are found to be low in irrigated water, it may be considered as a potential source of soil pollution due to their accumulation process in the agricultural land and may lead to risk on human health by consuming the agricultural products irrigated by contaminated water.

Dioxin and PCB residues in meats from Italy: Consumer dietary exposure.

In order to investigate PCB and PCDD/F concentrations and potential human health risk a study has been conducted in meat samples (beef, pork, chicken and turkey) purchased from Italian supermarkets. PCBs were dominant (41.8-77.7 ng g-1 l.w.) with respect to PCDD/Fs (20.1-91.1 pg g-1 l.w.). The levels were variable and largely dependent upon the type of meat. Accumulation pattern showed a distribution typically reported for meat. PCBs tended to decrease from lowest to highest congeners, while for PCDD/Fs the concentration profile was dominated by highly chlorinated dioxins and furans. Concentrations of PCDD/Fs plus dl-PCBs and indicator PCBs exceeding the EU maximum permissible levels were found in 23.3% and 53.3% of the samples, respectively. Exposure estimates to PCDD/Fs plus dl-PCBs (0.08-4.16 pg WHO-TEQs kg-1 b.w. w.-1) were within the new limit proposed by the EFSA's expert panel, except for pork sausage, showing a twofold higher value. Concerning the exposure derived from indicator PCBs, the maximum level set by different European countries (10 ng kg-1 b.w. d.-1) was surpassed solely via consumption of pork sausage (17.22 ng kg-1 b.w. d.-1), thought also the estimated intake from hamburger consumption (6.88 ng kg-1 b.w. d.-1) merits attention being close to guideline limit.

RETRACTED: Threats of indicator polychlorinated biphenyls (PCBs) in six molluscs from market to food safety: A case study in Haikou City, China.

This article has been retracted: please see Elsevier Policy on Article Withdrawal (https://www.elsevier.com/about/our-business/policies/article-withdrawal). This article has been retracted at the request of the Editor-in-Chief and Authors. The article is a duplicate of a paper that has already been published in the Chinese language in the Journal of Ecology and Rural Environment, 34 (2018) 1091-1095. doi:10.11934/j.issn.1673-4831.2018.12.005). One of the conditions of submission of a paper for publication is that authors declare explicitly that the paper has not been previously published and is not under consideration for publication elsewhere. As such this article represents a misuse of the scientific publishing system. The scientific community takes a very strong view on this matter and apologies are offered to readers of the journal that this was not detected during the submission process.

Levels of polychlorinated biphenyls (PCBs) in whole milk powderand estimated daily intake for a population of children / Níveis de bifenilos policlorados (PCBs) em leite em pó integral e ingestão diária estimada para uma população infantil

ABSTRACT: Polychlorinated biphenyls (PCBs) are chemical contaminants classified as persistent organic pollutants. Although, their use has been banned for several decades, PCBs are still scattered in the environment and; therefore, all living organisms may be exposed to these compounds. Diet, especially fatty foods such as milk, has been recognized as one of the main sources of human exposure to PCBs. Hence, the aim of this study was to evaluate the residual levels of indicator PCBs in whole milk powder consumed by preschool children in the Municipality of Imbé, State of Rio Grande do Sul, Brazil and to determine the estimated daily intake of these PCBs through this food. Analyses were performed by GC-μECD and the results were confirmed by GC/MS. The PCBs 28, 52 and 153 displayed values ​​below the limit of quantification. The PCBs 138 and 180 showed mean values of 0.073 and 0.157ng.g-1 lipid, respectively. These values were below the reference limits established by the European Community. The estimated total daily intake of PCBs was 0.110ng.g-1 lipid of body weight per day, a value lower than that established by the legislations of Belgium and Norway.

RESUMO: Os bifenilos policlorados (PCBs) são contaminantes químicos classificados como poluentes orgânicos persistentes. Embora seu uso tenha sido banido há mais de décadas, os PCBs ainda encontram-se presentes no meio ambiente e portanto, todos os organismos vivos podem estar expostos a esses compostos. A alimentação, especialmente alimentos gordurosos, como leite, tem sido reconhecida como uma das principais fontes de exposição humana aos PCBs. Assim, o objetivo deste estudo foi avaliar os níveis residuais de PCBs indicadores em leite em pó integral consumido por pré-escolares no Município de Imbé, Rio Grande do Sul, e determinar a ingestão estimada desses PCBs por meio deste alimento. As análises foram realizadas em GC-µECD e os resultados foram confirmados em GC/MS. Os PCBs 28, 52 e 153 apresentaram valores abaixo do limite de quantificação. Os PCBs 138 e 180 apresentaram valores médios de 0,073 e 0,157ng.g-1 lipídio, respectivamente. Estes valores estavam abaixo dos limites de referência estabelecidos pela Comunidade Europeia. A ingestão diária total estimada de PCBs foi de 0,110ng.g-1 de peso corporal por dia, valor inferior ao estabelecido pelas legislações da Bélgica e da Noruega.

Indicator polychlorinated biphenyls (PCBs) and organochlorine pesticides (OCPs) in seafood from Xiamen (China): levels, distributions, and risk assessment.

Indicator polychlorinated biphenyls (PCBs) and organochlorine pesticides (OCPs) were determined in 289 seafood samples including fishes, crustaceans, and shellfish collected from six administrative regions in Xiamen of China. The residual levels of PCBs, dichlorodiphenyltrichloroethane and its metabolites (DDTs), and hexachlorocyclohexanes (HCHs) ranged