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Natural purification of pollutants is highly recognized as regulating ecosystem services; however, the purification capacity of tidal flats remains largely unknown and/or unquantified. A 60-day mesocosm transplant experiment was conducted in situ to assess the purification capacity of natural tidal flats. We adopted the advanced sediment quality triad approach, monitoring 10 endpoints, including chemical reduction, toxicity changes, and community recoveries. The results indicated that contaminated sediments rapidly recovered over time, particularly > 50% within a day, then slowly recovered up to ∼ 70% in a given period (60 days). A significant early reduction of parent pollutants was evidenced across all treatments, primarily due to active bacterial decomposition. Notably, the presence of benthic fauna and vegetated halophytes in the treatments significantly enhanced the purification of pollutants in both efficacy and efficiency. A forecast linear modeling further suggested additive effects of biota on the natural purification of tidal flats, reducing a full recovery time from 500 to 300 days. Overall, the triad approach with machine learning practices successfully demonstrated quantitative insight into the integrated assessment of natural purification.

Despite its reputation as one of the cleanest regions globally, recent studies have identified the presence of various persistent toxic substances (PTSs) in the environmental matrices collected from Svalbard. This study investigated the chronological distribution and potential sources of 81 PTSs in soils from the glacier foreland of Midtre Lovénbreen. Soil samples (n = 45) were categorized by age based on exposure to the atmosphere due to glacier retreat in July 2014 into five age groups: 80–100 years (n = 7), 60–80 years (n = 12), 40–60 years (n = 16), 20–40 years (n = 7), and <20 years (n = 3). Concentrations of polychlorinated biphenyls (PCBs, n = 32) in soils varied with age, ranging from 0.29 to 0.74 ng g−1 dw. In addition, the concentrations of polycyclic aromatic hydrocarbons (PAHs, n = 28), perylene, and alkyl-PAHs (n = 20) in soils ranged from 21 to 80 ng g−1 dw, 2.9–62 ng g−1 dw, and 73–420 ng g−1 dw, respectively. The concentrations of PTSs were observed to be greater in older soils. Principal component analysis revealed that PCBs in soils originated from various product sources. Positive matrix factorization modeling estimated the association of PAHs in soils with potential origins, such as diesel emissions, petroleum and coal combustion, and coal. Potential sources of PAHs were mainly coal in younger soils and diesel emissions and petroleum combustion in older soils. Alkyl-PAH compositions in the soil were similar to those of bituminous coal, with a noteworthy degree of weathering observed in older soils. The accumulation rate and flux of PTSs in soils exhibited compound-specific patterns, reflecting factors such as long-range transport, fate, origin, and recent inputs. These findings can serve as baseline data for protecting and preserving polar environments. [Display omitted] • PTS concentrations were higher in older soils than in younger soils. • PAH sources were mainly coal in younger soils and diesel emissions in older soils. • Alkyl-PAHs originated from bituminous coal and were highly weathered in older soils. • Accumulation rate and flux of PTSs in soils exhibited compound-specific patterns. [ABSTRACT FROM AUTHOR]

Environmental pollution always threatens the public health of our country, and the incidence of diseases closely related to environmental pollution has continued to rise in recent years. With the rapid urbanization and industrialization, the pollutions of persistent toxic substances (PTS) in air, water, and soil constitute a major hidden danger, which are urgent to be investigated for ecological safety and environmental health risks. In order to solve realistic environmental issues, the potential health hazards of PTS desire to be uncovered through interdisciplinary research. In this article, we review the background and development history of environmental health research on PTS, as well as the current status and recent trend in this field. We also discuss the main scientific issues and challenges in this aspect, and elaborate policy recommendations for the development of environmental health research on PTS. [ABSTRACT FROM AUTHOR]

Abstract Hyperuricemia is becoming a serious public health issue, which is highly influenced by environmental factors, although there is still controversial information on the potential influence of the exposure to Persistent Toxic Substances (PTSs) in the general population. In this study we aimed to assess the association. PTS exposure with uric acid homeostasis in a sample of the Spanish population. Participants were recruited during 2009–2010 in all the main geographical areas of Spain. Exposure to 34 PTSs was estimated by chemical analyses of serum levels of 6 Polychlorinated Biphenyls (PCBs, n = 950), 13 Organochlorine Pesticides (OCPs, n = 453), 6 Perfluoroalkyl Substances (PFAs, n = 755), 7 Polybrominated Diphenyl Ethers (PBDEs, n = 365), urinary Cadmium (n = 926), and Lead in whole blood (n = 882). The two study outcomes were defined as the prevalence of hyperuricemia in the study population and uric acid levels, the latter only in individuals with no previous diagnosis of hyperuricemia. Statistical analyses were performed by means of binomial logistic regression and linear regression, and mixture effects were screened using Weighted Quantile Sum Regression (WQS). Serum concentrations of γ-HCH, o,p´- DDE, PCB-138, PCB-153, PFOA, and urinary Cadmium were associated with an increased risk of hyperuricemia, while PBDE-153 showed an inverse association with the effect. Furthermore, exposure to Cadmium, PCB-138, and to PCB-153 was positively associated with uric acid levels. Results were consistent after lipid adjustment or standardization. WQS analyses revealed a major contribution of PCB-153 within the PCB mixture on both the risk of hyperuricemia and uric acid levels. Sensitivity analyses were performed by adjusting for dietary habits, fasting glucose and estimated glomerular filtration rate. Overall, we found novel associations between human exposure to mixtures of PTSs and disturbances in uric acid homeostasis. However, we cannot completely rule out potential residual confounding effect or reversed-causality related to the cross-sectional design. Highlights • We assessed the contribution of PTSs on uric acid homeostasis in Spanish population. • Concentrations of 34 PTSs were analyzed in serum or urine. • PCB-138, PCB-153, PFOA, and Cadmium were positively associated with hyperuricemia. • Cadmium, PCB-138, and PCB-153 were positively associated with uric acid levels. • WQS analyses revealed a major effect of PCB-153 within the PCB mixture. [ABSTRACT FROM AUTHOR]

This paper analyzes the ways in which pregnant and breastfeeding women perceive the presence of chemical substances in food products. It also deals with how they reflect on the effects of those substances on their own health and that of the baby and the foetus when they think about processes of accumulation, transmission and elimination of those substances inside their bodies. Our first hypothesis is that women's discourses about the health effects of Persistent Toxic Substances (PTS) is related to the social distance of the social actors that reproduce these discourses. The acceptability of these discourses is more evident the greater is the trust in the social actors who transmit this information. This paper analyzes the discourses of health workers and the close social environment of these women, since both play an essential role in the transmission of these discourses. Despite the fact that the dietary advice received by women is strongly medicalized, the information provided on chemical substances in food in the medical environment is scarce and not homogeneous. Thus, this type of risk is made invisible in the doctor-patient relationship, and the responsibility for managing it usually falls on women. [ABSTRACT FROM AUTHOR]

Over the past century, industrialization and urban practices have resulted in the contamination of the Great Lakes ecosystem-the world's largest surface freshwater system-that provides drinking water and recreation to more than 40 million residents. In 2010, the Great Lakes Restoration Initiative was launched to accelerate efforts to protect and restore the Great Lakes and surrounding areas. Funded by GLRI, the Agency for Toxic Substances and Disease Registry initiated the Biomonitoring of Great Lakes Populations (BGLP) program. The objective of the program is to assess human exposure to legacy and emerging contaminants in the Great Lakes by measuring the body burden of contaminants in potentially susceptible populations. The BGLP program consists of a series of cross-sectional studies carried out collaboratively with states that are funded through ATSDR. The first BGLP Program (BGLP-I) began in 2010 and was completed in September 2015 through cooperative agreements with state health departments in Michigan, Minnesota, and New York. The three state programs targeted susceptible adult populations living in designated areas of contamination. Contaminants measured in all populations include mercury, lead, mirex, hexachlorobenzene, dichlorodiphenyltrichloroethane, and selected polychlorinated biphenyl congeners. In addition, some chemicals of emerging concern, such as per- and polyfluoroalkyl substances, were measured in several populations. The biomonitoring results helped guide public health actions to mitigate chemical exposures in these vulnerable Great Lakes populations. We provide an overview of the BGLP-I program's study populations, designs, and general methods. This overview provides a lead-in for subsequent manuscripts that present human biomonitoring data for legacy and emerging contaminants in culturally diverse susceptible populations-i.e., shoreline anglers, sport anglers, American Indians, and Burmese immigrants-residing in seven areas of concern. [ABSTRACT FROM AUTHOR]

Aunque en España se han realizado estudios sobre concentraciones en medios biológicos humanos de compuestos tóxicos persistentes (CTP) desde hace varias décadas, no se ha llevado a cabo una revisión sistemática. Los objetivos fueron: a) identificar los estudios realizados en España en los últimos 30 años que hubiesen determinado concentraciones en humanos de diclorodifeniltricloroetano (DDT), diclorodifenildicloroeteno (DDE), hexaclorobenceno (HCB), hexaclorociclohexanos (HCH) y policlorobifenilos (PCB), y b) sintetizar las principales características y resultados de cada estudio. Los estudios son sumamente heterogéneos y la mayoría carece de representatividad poblacional. Las concentraciones de DDT y DDE parecen haber decrecido moderadamente en los últimos 20 años. Hay numerosas fluctuaciones en los valores de HCB, HCH y PCB, en algún caso compatibles con un estancamiento. Se observan grandes diferencias en los valores detectados en los distintos estudios y dentro de un mismo grupo: las concentraciones de CTP de algunos individuos pueden llegar a ser más de 200 veces superiores a los de otros. La magnitud real de la contaminación humana por CTP y sus tendencias a lo largo del territorio español, así como su diversidad geográfica y social, siguen siendo ampliamente desconocidas.No systematic review is available on studies conducted in Spain on human concentrations of persistent toxic substances (PTS). The objectives were: to identify studies conducted in Spain in the past 30 years that determined concentrations in humans of dichlorodiphenyltrichloroethane (DDT), dichlorodiphenyldichloroethane (DDE), hexachlorobenzene (HCB), hexachlorocyclohexane (HCH) and polychlorinated biphenyls (PCBs); and to summarize the main characteristics and results of each study. Studies are highly heterogeneous and most lack population representativeness. Concentrations of DDT and DDE might have decreased moderately in the last 20 years. Numerous fluctuations are apparent in levels of HCB, HCHs and PCBs, in some instances compatible with some stagnation. There are enormous differences in levels detected across and within studies: PTS concentrations of some individuals may be over 200-fold higher than those of others. The actual magnitude of human contamination by PTS and their trends across Spain -as well as the geographic and social heterogeneity- remain largely unknown.

Distribution and sources of polychlorinated biphenyls (PCBs) and polycyclic aromatic hydrocarbons (PAHs) in the glacimarine sediments (35 sites) of Svalbard were investigated. PCBs (32 congeners), traditional PAHs (15 homologs), emerging PAHs (11 homologs), and alkylated PAHs (16 homologs) were widely distributed in the Svalbard sediments (ranges: below method detection limit to 20, 21 to 3600, 1.0 to 1400, and 31 to 15,000 ng g−1 dry weight, respectively). Compositional analysis indicated that PCBs mainly originated from combustion sources, with PAHs being strongly influenced by local sources. Positive matrix factorization analysis showed that PAHs were associated with vehicle and petroleum combustion, coal, and coal combustion. Coal-derived PAHs contributed significantly to the sediments of Van Mijenfjorden. Remnants of coal mining activity trapped in the permafrost appear to enter the coastal environments as ground ice melts. Consequently, PAHs are currently emerging as the most significant contributors to potential risks in the Svalbard ecosystems. [Display omitted] • Distributions of PCBs and PAHs in the sediments of Arctic Svalbard were investigated. • Hornsund and Van Mijenfjorden showed relatively high concentrations of PAHs. • PAHs in Svalbard sediments mainly originated from local coal and petrogenic sources. • PAHs contributed greatly to the potential ecological risks of sediments in Svalbard. [ABSTRACT FROM AUTHOR]

The present article presents an assessment of PTS in Brazil including polychlorinated biphenyls, polycyclic aromatic hydrocarbons, benzene hexachloride, aldrin, dieldrin, endrin, p,p,-DDT, p,p,DDE, p,p,-DDD, hexachlorocyclohexanes (alpha-HCH, beta-HCH, gamma-HCH and delta-HCH), endossulfan, heptachlor and pentachlorophenol. The data presented here are related to a survey of PTS levels in different environmental matrixes (soil, sediment, water, air, biota) and human tissues (milk, blood, human hair), according to the scope of the UNEP-GEF Regionally Based Assessment of PTSs. Potential sources were evaluated considering national products and imports, since most of the literature does not allow source identification. Finally, Brazilian legislation was updated.

Semi-volatile pollutants can undergo long-range atmospheric transport from low-altitude source regions to high-altitude regions and then accumulate in surface matrices (soil and plants). The Himalayas is the highest mountain range worldwide, but there have been limited studies on the source, transport, and deposition of polycyclic aromatic hydrocarbons (PAHs) and mercury (Hg) in the region. In this study, atmospheric PAHs, and the PAHs and Hg in soil and foliage were determined along a transect on a southern slope of the Himalayas, Nepal. The study showed anthropogenic emissions of PAHs and Hg occurred in the lowland areas of Nepal, and upslope transport to the high-altitude regions happened for both pollutants. During the upslope transport, forest filter effect and snow scavenging may be the important factors that enhance the deposition of PAHs, contributing to the negative pattern between concentrations of PAHs and altitudes. On the contrary, more Hg accumulated in the high Himalayas, relating to the enhanced deposition in the high altitude caused by the higher input from upper atmosphere. [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

An impedimetric sensor for persistent toxic substances, including organic pollutants and toxic inorganic ions is presented. The persistent toxic substances are detected using an ultrasensitive technique that is based on electron‐transfer blockage. This depends on the formation of guest–host complexes, hydrogen bonding, or a cyclodextrin (CD)‐metal complex (Mm(OH)n−β‐CD) structure between the target pollutants and β‐CD. [ABSTRACT FROM AUTHOR]

Fish and fishery products may represent one of the main sources of dietary exposure to persistent toxic substances (PTSs) such as polychlorinated dibenzodioxins, dibenzofurans, and biphenyls; polybromodiphenyl ethers; organochlorine pesticides; perfluorooctanoic acid and perfluorooctane sulfonate; and inorganic mercury and methyl mercury. In this study, PTS contamination of Mediterranean fish and crustaceans caught in Italian coastal waters was investigated in order to increase the representativeness of the occurrence database for wild species. The objectives were to verify the suitability of regulatory limits for PTSs, identify background concentrations values, if any, and examine the possible sources of variability when assessing the chemical body burdens of aquatic species. Twelve wild species of commercial interest and two farmed fish species were chosen. Excluding methyl mercury, chemical concentrations found in wild species fell generally towards the low ends of the concentration ranges found in Europe according to EFSA database and were quite lower than the tolerable maximum levels established in the European Union; farmed fish always showed contamination levels quite lower than those detected in wild species. The data obtained for wild species seemed to confirm the absence of local sources of contamination in the chosen sampling areas; however, species contamination could exceed regulatory levels even in the absence of specific local sources of contamination as a result of the position in the food web and natural variability in species' lifestyle. A species-specific approach to the management of contamination in aquatic organisms is therefore suggested as an alternative to a general approach based only on contaminant body burden. A chemical-specific analysis performed according to organism position in the food chain strengthened the need to develop this approach. [ABSTRACT FROM AUTHOR]

Abstract: The priority control screening (PCS) and water quality benchmarking (WQB) of toxic chemicals in water are key steps to ensure the safety of drinking water and aquatic ecosystem that is the crucial goal of water environment management. Owing to the different levels of social-economic development in different countries and regions, the PCS and WQB of toxic chemicals must be determined in accordance with their specific water environment situations. However, in China, the PCS and WQB of toxic chemicals in water were mainly introduced from the other countries. A method for the PCS and WQB of toxic chemicals in water based on the ecological risks was proposed, and a platform named Bayesian Matbugs Calculator (BMC) was developed. As a case study, the WQB and PCS of sixty-nine PTSs based their ecological risks were performed on the basis of one-year monthly monitoring in Lake Chaohu. The results showed that the current national water quality criteria (WQC) would underestimate the toxicological risk to organisms in this aquatic ecosystem. It appears necessary to develop new WQC for the protection of aquatic organisms in Lake Chaohu. Four grades of priority control chemicals (PCCs) in Lake Chaohu were proposed. The highest priority was assigned to organonitrogen-phosphorus pesticides, including parathion, dichlorvos, malathion, omethoate, and di-n-butyl phthalate. However, the national “blacklist” of toxic compounds only covered 7 of 20 PCCs, indicating that the other 13 PCCs would not be controlled efficiently. Because the pollution pattern of PTSs in various water bodies might be quite different, we appealed to the governments to screen the regional PPC lists or develop a more comprehensive national list for aquatic ecosystem protection in China. [Copyright &y& Elsevier]

Abstract: Mariculture activity has increased its production along the Atlantic Coast of Brazil over the last years. This protein source for human consumption may also represent risks due to the exposure to bioaccumulated contaminants in the tissues of organisms reared in polluted shallow waters. This study evaluated the bioaccumulation of pesticides and dioxin-like compounds in two commercial marine bivalve species reared at different sites along the Rio de Janeiro State coast (SE-Brazil). We observed distinct contamination profiles in bivalve tissues reared at each sampling site, which may be related to human activities historically developed in those areas. A pronounced tendency for higher contamination levels in animals sampled in the last month of winter (September) is discussed as being likely due to environmental issues, rather than biological factors. Based on Minimal Risk Level, Maximum Residue, Acceptable Daily Intake and Toxic Equivalent, bivalves are classified as safe for human consumption. [Copyright &y& Elsevier]

A case study of the cancer risk to humans posed by persistent organic pollutants (POPs) in an industrial area of China, which has a long history of contamination from many sources, is presented. Relatively great concentrations of POPs around the chemical industrial parks have the potential to be chronically carcinogenic to local people. Sixteen individual PAHs listed for priory control by the U.S. Environmental Protection Agency (USEPA), metabolites of DDTs, and isomers of HCHs were measured in soils and a human health risk assessment was conducted by use of USEPA exposure models for children and adults, respectively. Geostatistical methods were used to simulate the spatial diffusion of potential carcinogenic risk, and non-parametric Mann-Whitney U and Kruskal-Wallis tests were employed to analyze the impact of point sources on the surrounding area. The mean value of the sum of Excess Lifetime Cancer Risk (∑ELCR) exceeded the generally acceptable risk level of 1.0E-06 recommended by the USEPA for carcinogenic chemicals. The maximum ∑ELCR was 2.9E-04 for children, which was observed inside the chemical industrial parks. Contamination at the chemical industrial parks caused significant spatial diffusion of ELCR values caused by PAHs, DDT, and HCH. [ABSTRACT FROM AUTHOR]

Uncontrolled electronic-waste (e-waste) recycling processes have induced serious environmental pollution and human health impacts. This paper reviewed studies on the wide range of toxic chemicals through the use of primitive recycling techniques, their transfer to various ecological compartments, and subsequent health impacts. Results indicated that local food items were heavily polluted by the pollutants emitted, notably heavy metals in vegetables, rice, fish and seafood, and persistent organic pollutants (POPs) in livestock. Dietary exposure is the most important exposure pathway. The associations between exposure to e-waste and high body burdens of these pollutants were evident. It seems apparent that toxic chemicals emitted from e-waste activities are causing a number of major illnesses related to cardiovascular, digestive and respiratory systems, according to the information provided by a local hospital (Taizhou, an e-waste recycling hot spot in China). More epidemiological data should be made available to the general public. It is envisaged that there are potential dangers of toxic chemicals passing on to the next generation via placental transfer and lactation. There is a need to monitor the development and health impacts of infants and children, born and brought up in the e-waste sites. [Display omitted] • Local food in e-waste sites is heavily polluted, notably Cd, Pb, PBDEs and PCBs. • Dietary exposure is more related to the body burdens of toxic chemicals. • Toxicants from e-waste sites cause cardiovascular, digestive and respiratory related illnesses. • Epidemiological data in e-waste recycling sites should be made available to the general public. • Understanding of adverse health impacts of toxicants on younger generation should be investigated. [ABSTRACT FROM AUTHOR]

Abstract: Assessing the adverse effects on human health of persistent organic pollutants (POPs) and the impact of policies aiming to reduce human exposure to POPs warrants monitoring body concentrations of POPs in representative samples of subjects. While numerous ad hoc studies are being conducted to understand POPs effects, only a few countries are conducting nationwide surveillance programs of human concentrations of POPs, and even less countries do so in representative samples of the general population. We tried to identify all studies worldwide that analyzed the distribution of concentrations of POPs in a representative sample of the general population, and we synthesized the studies'' main characteristics, as design, population, and chemicals analyzed. The most comprehensive studies are the National Reports on Human Exposure to Environmental Chemicals (USA), the German Environmental Survey, and the Arctic Monitoring and Assessment Programme. Population-wide studies exist as well in New Zealand, Australia, Japan, Flanders (Belgium) and the Canary Islands (Spain). Most such studies are linked with health surveys, which is a highly-relevant additional strength. Only the German and Flemish studies analyzed POPs by educational level, while studies in the USA offer results by ethnic group. The full distribution of POPs concentrations is unknown in many countries. Knowledge gaps include also the interplay of age, gender, period and cohort effects on the prevalence of exposures observed by cross-sectional surveys. Local and global efforts to minimize POPs contamination, like the Stockholm convention, warrant nationwide monitoring of concentrations of POPs in representative samples of the general population. Results of this review show how such studies may be developed and used. [Copyright &y& Elsevier]

Bivalve mussels are usually used for biomonitoring persistent toxic substances (PTS) in coastal ecosystems. Nevertheless, these organisms, which live attached on hard substrates, can be found along the sandy coasts only on human manufactured products. In this work different species collected in the Gulf of Gdańsk were compared to evaluate their suitability for monitoring PTS pollution at a local scale. The clam Mya arenaria seems to represent an excellent indicator of sediment pollution, mainly for organotin compounds which are selectively bioaccumulated. Organochlorine compounds are bioaccumulated in the different species mainly in function of their lipid body burden. Habitat conditions (salinity, substrate, pollution), however, strongly limited the occurrence of different species in the sampling sites; the most ubiquitous species, the common shrimp Crangon crangon, resulted therefore the most suitable to be used for the comparison of PTS pollution in this aquatic environment. Although the blue mussel (Mytilus trossulus) was confirmed to be a very useful sentinel species to compare pollution level inside and outside the Gulf of Gdańsk, we recommend the use of other species to give a more detailed picture of the pollution situation in coastal areas. [Copyright &y& Elsevier]

The results are presented of a survey planned to assess the presence of high concern chemicals in sediments collected in a northern sector of the Adriatic sea neighboring the Venice lagoon. For the assessment, persistent marker chemicals were selected from the families of polycyclic aromatic hydrocarbons, polychlorobiphenyls, polychlorodibenzo-p-dioxins (PCDDs), polychlorodibenzofurans (PCDFs), and chlorinated pesticides. Based on the chemical-specific concentrations and PCDD+PCDF profiles determined in the sediments analyzed, dumping zones appear to have existed approximately 5–6km away from lagoon shoreline. Contamination levels exceed the quality criteria established by the pertinent Italian national regulation at many sampling sites, eventually reflecting (“fingerprinting”) industrial activities once performed in the industrial settlement of Porto Marghera within the Venice lagoon. In coastal samples, concentration levels appear to be lower than those determined at offshore sampling sites. [Copyright &y& Elsevier]

In the United States, some 80,000 commercial and industrial chemicals are now in use of which over 30,000 are produced or used in the Great Lakes region. Thus, the environmental quality within the Great Lakes basin has been compromised particularly with respect to persistent toxic substances (PTS). Information derived from wildlife studies, prospective epidemiological and toxicological studies, databases, demographics, and Geographical Information Systems (GIS) demonstrate significant public health implications. Studies of human populations indicate: ( a) elevated body burden levels of PTSs, ( b) decrease in gestational age, ( c) low birth weight (LBW), ( d) greater risk of male children with birth defects (OR = 3.01), ( e) developmental and neurological deficits, ( f) increased risk of infertility, ( g) changes in sex ratio, and ( h) fluctuations in thyroid hormones. These findings have been identified in vulnerable populations, such as the developing fetus, children, minorities, and men and women of reproductive age who are more susceptible because of their physiologic sensitivity and/or elevated exposure to toxic chemicals. Typically such health effects are assessed on a chemical specific basis; however, most human populations are exposed to hazardous chemicals as mixtures in air, water, soil, and biota. In this article we present an assessment of the potential for joint toxic action of these substances in combinations in which they are typically found. These evaluations represent an integration of all available scientific evidence in accordance with the “NAS paradigm” for risk assessment. In aggregate, our evaluations have demonstrated a need for community-based frameworks and computational techniques to track patterns of environmentally related exposures and associated health effects. [ABSTRACT FROM AUTHOR]

The objective of this review is to provide a comprehensive assessment of the threats posed by persistent toxic substances (PTS) to the environment and human health in Egypt and to identify priorities, data gaps and recommendations for future intervention to control, reduce or eliminate releases of PTS. Data on available concentrations of persistent toxic substances in the different environmental compartments and their impacts on the ecosystem, and humans have been assembled and summarized. Despite extensive studies, most of the data available deal with limited studies or hot spot situations. Localized inputs of PTS have been identified from freshwater discharges in coastal areas (e.g., Nile estuaries and coastal lakes) and near sewage outfalls from highly industrialized and populated cities. Data are often missing for certain contaminants and in some compartments and geographical areas. The lack of standardized methodologies makes it difficult to compare and use existing data to provide exact conclusions on spatial and temporal trends. In spite of these restrictions, available data indicate that it is unlikely that present levels of cyclodiene pesticides would adversely affect marine organisms. Compounds which are proven to be of concern are DDT, PCBs, γ-HCH, PAHs, HCB and organotin compounds. Other compounds are suspected to be ubiquitous but data are lacking. Based on few recent data, the reported levels of organochlorine pesticides in fish and human milk samples suggest a concentration decline during the 1990s consistent with the regulatory restrictions on the use of these compounds. It is essential to activate monitoring programs to fill data gaps in appropriate abiotic and biotic. Monitoring programs should be follow standard procedures and include improved QA/QC protocols. [Copyright &y& Elsevier]

We investigated the sedimentary pollution by persistent toxic substances (PTSs) and their potential impacts on the macrobenthic faunal community in the Geum River Estuary, South Korea. Sediment and benthic macrofauna samples were collected from eight sites every two months during the period of February to December in 2015. Target PTSs encompassed metals (Cd, Cr, Cu, Hg, Ni, Pb, and Zn), one metalloid (As), polycyclic aromatic hydrocarbons (PAHs), and alkylphenols (APs). The significant difference to the environment of the inner and outer parts of the estuary (p < 0.05) was found with relatively high concentrations of PTSs in sediment from the inner estuary. The concentrations of Cu and Zn exceeded the sediment quality guidelines of Korea representing a potential risk to aquatic organisms. The primary source of PAHs was by-products of diesel and gasoline combustion (37%), followed by a coke oven (32%) and oil-burning (31%). The macrofaunal community was spatially distinguished between the inner and outer parts of the estuary (p < 0.05), regardless of the season. In the inner part of the estuary, the density of the macrofaunal community was high, due to the increased opportunistic species and/or some indicator species (organic polluted or enrichment), implying that the given environment was disturbed. Among the environmental parameters analyzed by the distance-based linear model (DistLM), salinity, chlorophyll- a , and nutrient concentrations were found to be key factors controlling the changes in macrofaunal community structure. Such changes in the closed estuary system would indicate that each taxonomic group had to adjust to lower salinities and alternative food sources. Overall, the distribution of PTSs and macrozoobenthic communities in the Geum River Estuary collectively reflected the environmental gradients caused by surrounding activities in the inner part of the estuary together with direct effects by the irregular inflow of freshwater. Unlabelled Image • Benthic environment of estuary is clearly divided as the inner and outer parts of estuary. • PTSs concentrations are obviously high in the inner part of estuary within one year-round. • Concentrations of Cu and Zn within one year-round pose a potential ecological risk. • Spatial variation of macrofaunal community prevailed with no seasonal fluctuations. • Salinity and chlorophyll- a were key factors that determine macrofaunal assemblages. [ABSTRACT FROM AUTHOR]

This research aims to explore clusters of a mixture of 15 Persistent Toxic Substances (PTSs) in the adipose tissue of 227 individuals of an adult cohort from Granada Province (Southern Spain). Information about residence and occupation during participants lifetime was gathered by means of validated questionnaires. Clusters of pollutants in the study population were identified by Principal Component Analyses (PCA). PCA analyses revealed three major clusters of pollutants: PC1, representing predominantly an assortment of metal(loid)s, namely aluminium, arsenic, chromium, nickel and lead; PC2, including mostly Organochlorine Pesticides (OCPs), such as HCB, β-HCH and p,p' -DDE; and PC3, gathering mainly a mixture of Polychlorinated Biphenyls (PCB-138, PCB-153 and PCB-180) and metals (cadmium, cobalt and chromium). The patterns of distribution of individual pollutants and their mixtures were explored through Geographic Information Systems and multivariable linear regression models. Living in rural areas was associated with decreased levels of the mixture of PCBs and metals. Residents of industrial and heavy traffic areas showed increased levels of the mixture of metal(loid)s. Those living in rural and semi-rural areas at recruitment had decreased levels of the OCP mixture. Occupational history related to agriculture and food industry was associated with increased levels of the mixture of metal(loid)s, whereas those who had been involved in motor and industrial activities showed increased levels of the OCP mixture. Participants who had worked in cleaning and housekeeping activities for long periods showed decreased levels of the mixture of PCBs and metals. Our research revealed suggestive clusters of exposure, that emphasized the need for further epidemiological studies to address the effect of environmental pollutants from a mixture perspective. Results also highlight the potential of adipose tissue as a matrix for exposure assessment to combinations of different families of contaminants. Image 1 • We explored mixtures of persistent pollutants in adipose tissue of 227 adults. • We studied associations of pollutant' concentrations with residence and occupation. • Relevant differences between urban, industrial and rural zones were found. • Exposure patterns differed depending on the occupational history. [ABSTRACT FROM AUTHOR]

• eDNA was used to characterize long-term changes in benthic bacterial communities. • Succession of certain bacterial taxa represented year-round chemical pollution. • Planctomycetes was indicative and/or sensitive taxa to PAH and Hg pollution. • ER-mediated potencies were correlated with benthic bacterial communities at class level. • Characterizing in situ bacterial communities was useful for sediment quality assessment. During the past few decades, contamination of sediments by persistent toxic substances (PTSs) has been observed in estuarine and coastal areas on the west coast of South Korea. The contaminants are suspected to cause toxicities in aquatic biota, but little is known about their ecological effects, particularly on benthic microbial communities. In this study, an eDNA-based assessment was applied along with classic assessments of exposure, such as chemistry and in vitro bioassays, to evaluate condition of benthic bacterial communities subjected to PTSs. Two strategies were adopted for the study. One was to conduct a comprehensive assessment in space (by comparing seawater and freshwater sites at five coastal regions) and in time (by following change over a 5-y period). Although we found that bacterial composition varied among and within years, some phyla, such as Proteobacteria (28.7%), Actinobacteria (13.1%), Firmicutes (12.7%), and Chloroflexi (12.5%) were consistently dominated across the study regions. Certain bacterial groups, such as Firmicutes and Verrucomicrobia have been linked to contamination at some sites in the study area and at specific points in time. Bacterial communities were not significantly correlated with salinity or AhR- and ER-mediated potencies, whereas concentrations of PAHs, APs, and certain metals (Cd and Hg) exhibited significant associations to the structure of bacterial communities at the phylum level. In fact, the relative abundance of microbes in the phylum Planctomycetes was significantly and negatively correlated with concentrations of PAHs and metals. Thus, the relative abundance of Planctomycetes could be used as an indicator of sedimentary contamination by PAHs and/or metals. Based on our correlation analyses, Cd and ER-mediated potencies were associated more with bacterial abundances at the class taxonomic level than were other PTSs and metals. Overall, the eDNA-based assessment was useful by augmenting more traditional measures of exposure and responses in a sediment triad approach and has potential as a more rapid screening tool. [ABSTRACT FROM AUTHOR]

The objective of this study was to explore what motivates pregnant and breastfeeding women to make changes in their diet, specifically to examine how their perceptions regarding diet facilitate or act as obstacles to introducing healthy eating habits. For the optimal development of the mother, the fetus, or breastfeeding baby, it is important to avoid foods containing substances, such as persistent toxic substances (PTSs), that are harmful to health during pregnancy and after the baby's birth. This study used a qualitative research methodology, based on semi-structured individual interviews, food diaries, free lists, and focus groups with 111 pregnant and breastfeeding women in Spain. This approach was followed by a systematic and exhaustive exploitation of the qualitative data obtained, following the methodological principles of grounded theory. From the study results, we conclude that the motivation for a change in diet to avoid PTSs is based on the desire to promote good health, beliefs about the importance of having a varied diet, and the avoidance of potential risks. The main obstacles to change can be attributed to inadequate information, contradictory discourses, and socioeconomic difficulties.

We conducted an observational study of 194 pregnant women from two different study sites in rural Cambodia. Socioeconomic and anthropometric data was obtained from the women and their newborns. In addition, we collected blood and urine samples from the women for further analyses in planned papers. There were significant differences between the two study groups for clinical outcomes. The mothers from the poorer area were shorter and weighed less at the time of inclusion. Their babies had significantly smaller head circumferences and a lower ponderal index. Conclusion: There are significant anthropometric differences between women and their newborns from two separate study sites in Cambodia. Possible associations between stunting and exposure to Persistent Toxic Substances (PTS) as organochlorines and toxic trace elements will be investigated in future studies.