Perfluorinated Compounds

Persistent organic pollutants (POPs) are industrial chemicals and ubiquitous global contaminants. They share properties of persistence, toxicity, bioaccumulation potential and propensity for long-range environmental transport. POPs are recognised as posing a threat to environmental and human health and are subject to the Stockholm Convention on Persistent Organic Pollutants. Since the first group of POPs were listed under the Stockholm Convention, an increasingly diverse range of chemicals from consumer products have been included under the Convention [1] .

This commentary argues that the field of criminology can aid in addressing PFAS (per-and polyfluoroalkyl substances) pollution, providing levers to achieve public health aims of drastically lowering and abating new PFAS emissions while addressing historic exposure. Based on a European example of the large DuPont de Nemours (now Chemours) industrial facility in Dordrecht, the Netherlands, we frame the history of PFAS exposures as a crime. We discuss how PFAS pollution emerged in part due to knowledge asymmetries, perpetuated by the close alignment of corporate and governmental interests, and the fragmentation of regulatory enforcement, both historic and contemporary.

The purpose of this study was to evaluate the efficacy of a low-cost filter regarding per-and polyfluoroalkyl substances (PFAS). PFAS is a commonly used man-made chemical that can be found in a variety of household and industrial products with deleterious effects on humans. The filter consists of a combination of low-cost materials which could be locally procured. Water testing results for 4 different PFAS contaminants indicated that for Perfluorooctane sulfonic acid (PFOS), the Agency for Toxic Substances and Disease Registry (ATSDR) regulation is 7 ppt, the initial concentration was 15 ppt, and the final concentration was 3.9 ppt. For Perfluorononanoic acid (PFNA), the ATSDR regulation is 10.5 ppt, the initial concentration was 15 ppt, and the final concentration was 3.9 ppt. For Perfluorooctanoic acid (PFOA), the ATSDR regulation is 11 ppt, the initial concentration was 15 ppt, and the final concentration was 3.9 ppt. For Perfluorohexane sulfonic acid (PFHxS), the ATSDR regulation is 70 ppt, the initial concentration was 15 ppt, and the final concentration was 3.9 ppt. The results indicated a 74% reduction in PFAS concentration in filtered samples. Statistical data through regression analysis showed 0.9 validity of the sample data. Initial tests show the efficiency of the proposed filter described could be far greater if tested at a greater scale. It is highly recommended further testing to be conducted to validate the data for an innovative solution to a ubiquitous problem.

Perfluorinated compounds (PFCs), synthetic musks compounds (SMCs), bisphenol A (BPA), para-nonylphenol (p-NP) and polybrominated diphenyl ethers (PBDEs) are known for their toxicity and ability to interfere with the endocrine system. The aim of this study was to determine levels and distribution of the above mentioned compounds in liver samples of Caretta caretta and levels of porphyrins that have been proposed as sensitive biomarkers of exposure to contaminants. This paper reports the results for 9 specimens yet analysed. Musk ketone was never detected, PFOA was found in one sample, while PFOS was the prevalent contaminant. For PFCs the levels are lower than the results of studies of comparison. The porphyrins profile showed a predominance of protoporphyrins on coproporphyrins and uroporphyrins, with a positive statistical correlation between levels of PFOS and uroporphyrins. These data represent, for several parameters, the first evidence of contaminant levels and biomarker responses in loggerhead turtles.

Many known purification systems have failed in the removal of per- and poly-fluoroalkyl substances (PFASs), and there is no known natural degradation process. PFAS are a group of synthetic fluoroorganic compounds that have a unique dual nature of both lipophobic and hydrophobic, as well as high-energy chemical bonds that make them pervasive in the environment. Currently, these compounds receive less attention; however, they pose serious health problems. Studies have shown PFAS's dispersion pathways, health concerns, and suggestions for their removal in soil and water, but there is still limited information on the natural or subjective degradation of the compounds. Several technologies, such as phytoremediation, reverse osmosis, nanofiltration, and photolysis, have been demonstrated to remove PFAS. However, these techniques come with their challenges and drawbacks, especially in the complete removal of the compounds. Thus, this overview described the pathways and mechanisms of some PFAS, including biotransformation pathways of 6:2 FTOH, biotransformation and degradation pathways of 8:2 FTOH, and fragmentation pathways for PFOA, PFOS, and 8:2 FTOH, degraded by the Phanerochaete chrysosporium fungus. Furthermore, this study suggests that the integration of plants and fungi into constructed wetland technology holds promise for effective PFAS removal.

Many known purification systems have failed in the removal of per-and poly-fluoroalkyl substances (PFASs), and there is no known natural degradation process. PFAS are a group of synthetic fluoroorganic compounds that have a unique dual nature of both lipophobic and hydrophobic, as well as high-energy chemical bonds that make them pervasive in the environment. Currently, these compounds receive less attention; however, they pose serious health problems. Studies have shown PFAS's dispersion pathways, health concerns, and suggestions for their removal in soil and water, but there is still limited information on the natural or subjective degradation of the compounds. Several technologies, such as phytoremediation, reverse osmosis, nanofiltration, and photolysis, have been demonstrated to remove PFAS. However, these techniques come with their challenges and drawbacks, especially in the complete removal of the compounds. Thus, this overview described the pathways and mechanisms of some PFAS, including biotransformation pathways of 6:2 FTOH, biotransformation and degradation pathways of 8:2 FTOH, and fragmentation pathways for PFOA, PFOS, and 8:2 FTOH, degraded by the Phanerochaete chrysosporium fungus. Furthermore, this study suggests that the integration of plants and fungi into constructed wetland technology holds promise for effective PFAS removal.

The chemical hazards associated with handling tetrafluoroethylene (TFE) on industrial production facilities are presented. TFE is an extremely flammable and chemically unstable gas. Even in the absence of oxygen, it can explosively decompose and unfortunately there have been many industrial accidents from the un-wanted ignition of TFE; some of which have resulted in fatalities and significant equipment damage. In addition to TFE property and toxicity data, this report presents some of the latest experimental data on TFE flammability and decompositions, particularly those caused by hot-spots and adiabatic (heat of) compression of other gases in pipes with a diameter up to 2.5 cm. Furthermore, details of potential ignition sources are discussed as are the risks and hazards of storing and handling TFE at industrial facilities. Examples of explosion protection equipment and procedures are given.

Exposure to environmental chemicals can modulate the developing immune system, but its role in the pathogenesis of type 1 diabetes is largely unexplored. Our objective was to study the levels of circulating concentrations of environmental pollutants during the first years of life and their associations with the later risk of diabetes-predictive autoantibodies. From two birth-cohort studies including newborn infants with HLA-conferred susceptibility to type 1 diabetes (FINDIA and DIABIMMUNE), we identified case children with at least one biochemical diabetes-associated autoantibody (n = 30-40) and from one to four autoantibody-negative controls per each case child matched for age, gender, diabetes-related HLA-risk, delivery hospital, and, in FINDIA, also dietary intervention group. Plasma levels of 13 persistent organic pollutants and 14 per-and polyfluorinated substances were analyzed in cord blood and plasma samples taken at the age of 12 and 48 months. Both breastfeeding and the geographical living environment showed association with circulating concentrations of some of the chemicals. Breastfeedingadjusted conditional logistic regression model showed association between decreased plasma HBC concentration at 12-monthold children and the appearance of diabetes-associated autoantibodies (HR, 0.989; 95% Cl, 0.978-1.000; P = 0.048). No association was found between the plasma chemical levels and the development of clinical type 1 diabetes. Our results do not support the view that exposure to the studied environmental chemicals during fetal life or early childhood is a significant risk factor for later development of β-cell autoimmunity and type 1 diabetes.

Fish samples of Baltic herring, sprat, flounder, perch, salmon, and river lamprey were collected from the Gulf of Finland in 2013 and 2014 with the aim to get an overview of the occurrence of pollutants in fish caught in Estonian waters. The content of non-dioxin-like polychlorinated biphenyls (ndl PCBs), polybrominated diphenyl ethers (PBDEs), organic tin (OT) and perfluorocompounds (PFAS) are examined and discussed in the study. The results revealed that potentially higher content of organo-tin compounds, perfluorocompounds and polybrominated diphenyl ethers in Baltic herring, salmon and river lamprey may cause concern regarding human exposure. It is important to link pollutant content to lipid content of fish taking into account their seasonal variation in different age classes.

Immune suppression may be a critical effect associated with exposure to perfluorinated compounds (PFCs), as indicated by recent data on vaccine antibody responses in children. Therefore, this information may be crucial when deciding on exposure limits. Results obtained from follow-up of a Faroese birth cohort were used. Serum-PFC concentrations were measured at age 5 years, and serum antibody concentrations against tetanus and diphtheria toxoids were obtained at age 7 years. Benchmark dose results were calculated in terms of serum concentrations for 431 children with complete data using linear and logarithmic curves, and sensitivity analyses were included to explore the impact of the low-dose curve shape. Under different linear assumptions regarding dose-dependence of the effects, benchmark dose levels were about 1.3 ng/mL serum for perfluorooctane sulfonic acid and 0.3 ng/mL serum for perfluorooctanoic acid at a benchmark response of 5%. These results are below average serum concen...

Per-and polyfluoroalkyl substances (PFASs) are a class of environmentally persistent industrial compounds that disrupt various metabolic pathways. Among the protein receptors to which PFASs bind, the human pregnane X receptor (hPXR) is found to be a host for a variety of long-and short-chain PFASs that lead to its overactivation. Overactivation of hPXR is linked to potential endocrine disruption, oxidative stress, hepatic steatosis, and adverse drug interactions. In this study, molecular dynamics (MD) is used to study the binding between hPXR and a number of PFAS compounds, including alternatives whose activity on hPXR has not been experimentally tested. This is the first-time MD is used to study the interactions between PFASs and hPXR, showing how relative binding free energies of PFASs relate to hPXR agonism. Binding free energy calculations, hydrogen bond analysis, per-residue decomposition calculations, and alanine scanning studies are done to provide further insight. Activities on hPXR for several short-chain and alternative PFAS compounds to long-chain PFASs that have yet to be reported will also be considered. These short-chain and alternative species include perfluorobutane sulfonic acid (PFBS), Gen-X (trade name for 2,3,3,3-tetrafluoro-2-heptafluoropropoxy propanoic acid), ADONA (trade name for 4,8-dioxa-3Hperfluorononanoic acid), and 6:2 fluorotelomer carboxylic acid (6:2 FTCA). The study shows key aspects of PFAS recognition on the hPXR, the link between PFAS binding to hPXR and the hPXR activity change observed upon the PFAS exposure, and the potential effects of alternative PFASs on hPXR activity.

Förekomst och effekter av globalt spridda persistenta organiska miljöföroreningar (POPs) har blivit en mycket uppmärksammad fråga. Två kategorier av kemikalier som har fått ökad uppmärksamhet är organiska flamskyddsmedel (FRs) och perfluoroalkylerade substanser (PFASs). Det har visat sig att många av dessa är bioackumulerande, persistenta och giftiga, vilket har lett att flera av dem fasats ut eller förbjudits under de senaste årtiondena. Eftersom FRs och PFASs är väl spridda i miljön och dessutom svåra att avlägsna från avloppsvatten, återfinns de regelbundet i ytvatten och i vissa fall även i grundvatten. Kunskap om FRs och PFASs i miljön är begränsad, både vad gäller förekomst, spridning och effekter, och särskilt då för ämnen som introducerats relativt nyligen (t.ex. nya FRs). Det finns alltså ett behov av att lära mer om dessa ämnen. Syftet med detta projekt var att studera förekomst av PFASs samt relativt nya FRs i vattendrag längs hela kusten. Vi provtog på 44 platser (totalt 41 vattendrag) och bestämde innehållet av PFASs (alla platser) och FRs (25 provtagningsplatser som representerar 23 vattendrag). Av de 12 utvalda FRs, kunde 3 kvantifieras (2,4,6-TBP, TCIPP och TPHP). TCIPP var det klart dominerade ämnet med en halt på upp till 3 900 ng L-1 (Fyrisån). 2,4,6-TBP uppvisade högre halter i åar i södra Sverige. Vattendraget med den högsta halten av FRs var Fyrisån, och den totala belastningen på Östersjön av FRs uppskattades till 38 kg dag-1 , där Ångermanlandsälven och Norrström stod för de största bidragen. Det ska noteras att dessa i belastningssiffror ingår bara de utvalda, relativt nya FRs, medan äldre med omfattande historisk användning, t.ex. PBDE, inte ingår. Totalt 13 av 25 de analyserade PFASs kunde kvantifieras (PFBA,

The water channels milestones include: the vague idea of "hydrophilic pores" or "water-filled channels" in the red blood cell (RBC), the proposal that water channels (WCh) are accommodated in proteins, experiments associating WCh with the major RBC membrane protein called Band 3 (the anion exchanger), and the crucial experiment performed in 1985 by Benga group in Cluj-Napoca, Romania, proving the presence and location of a minor protein of the RBC membrane involved in water transport. In the landmark papers of 1986, Benga introduced the concept of the WCh being a protein specialized in water transport, i.e. a water channel protein (WCP). The first WCP discovered by our group was rediscovered in 1992 by Agre group. In the same year two other WCPs were discovered. The name aquaporins was proposed in 1993. In subsequent years hundreds of WCPS have been discovered in organisms from all kingdoms of life. WCPs are a family of membrane proteins, belonging to the Membrane Intrinsic Proteins superfamily. WCPs family include three subfamilies: 1) aquaporins (AQPs) which are mainly water selective channels; 2) aquaglyceroporins are permeable to water and to other small uncharged molecules; 3) S-aquaporins (subcellular or superaquaporins). Benga called aquaglyceroporins and S-aquaporins the "relatives of aquaporins". Twelve WCPs were identified in the human body, having a great importance in a lot of physiological phenomena, as well as in pathological conditions, from well defined "water channelopathies" to a wide range of diseases. Benga propose the name of aquaporinology for the domain of biomedical and natural sciences dedicated to the integrated approach of WCPs (aquaporins and relatives), which is also a chapter of Cellular and Molecular Biology.

Since 2000, long-chain perfluoroalkyl acids (PFAAs) and their respective precursors have been replaced by numerous fluorinated alternatives. The main rationale for this industrial transition was that these alternatives were considered less bioaccumulative and toxic than their predecessors. In this study, we evaluated to what extent differences in toxicological effect thresholds for PFAAs and fluorinated alternatives, expressed as administered dose, were confounded by differences in their distribution and elimination kinetics. A dynamic onecompartment toxicokinetic (TK) model for male rats was constructed and evaluated using test data from toxicity studies for perfluorobutanoic acid (PFBA), perfluorohexanoic acid (PFHxA), perfluorobutane sulfonic acid (PFBS), perfluorooctanoic acid (PFOA), perfluoroctanesulfonic acid (PFOS) and ammonium 2,3,3,3-tetrafluoro-2-(heptafluoropropoxy)-propanoate (GenX). Dose-response curves of liver enlargement from sub-chronic oral toxicity studies in male rats were converted to internal dose in serum and in liver to examine the toxicity ranking of PFAAs and fluorinated alternatives. Converting administered doses into equivalent serum and liver concentrations reduced the variability in the dose-response curves for PFBA, PFHxA, PFOA and GenX. The toxicity ranking using modeled serum (GenX > PFOA > PFHxA > PFBA) and liver (GenX > PFOA ≈ PFHxA ≈ PFBA) concentrations indicated that some fluorinated alternatives have similar or higher toxic potency than their predecessors when correcting for differences in toxicokinetics. For PFOS and perfluorobutane sulfonic acid (PFBS) the conversion from administered dose to serum concentration equivalents did not change the toxicity ranking. In conclusion, hazard assessment based on internal exposure allows evaluation of toxic potency and bioaccumulation potential independent of kinetics and should be considered when comparing fluorinated alternatives with their predecessors.

Per-and polyfluoroalkyl substances (PFAS) are manmade, fluorinated organic chemicals which have been identified as persistent organic pollutants. PFAS have surface active properties that have made them suitable for applications in oil-and water-resistant products, as well as many firefighting foams. No on-site remediation strategies exist to treat PFAS impacted soils. Mechanochemical remediation of PFOS-and PFOA-amended sand via a planetary ball mill was studied. The effect of sand mass, KOH as a co-milling reagent, and water saturation on the degradation of PFOA and PFOS was evaluated. By 4 h of milling concentrations were reduced by up to 98% for PFOS-amended dry sand and 99% for PFOA-amended dry sand without the addition of a co-milling reagent. Water saturation was determined to be a significant hindrance on the mechanochemical destruction of PFOS and PFOA. A maximum of 89% of fluoride was recovered from PFOS-amended sand when KOH was used as a co-milling reagent. It is hypothesized that reactive particles generated from the fracture of sand grains react with PFAS molecules to initiate destruction, which can result in full defluorination. Milling experiments were also conducted on soils from a Canadian firefighting training area (FFTA), demonstrating that PFOS concentrations can be reduced by up to 96% in site soils. For the first time, ball milling for the remediation of PFAS in environmental media has been demonstrated using amended sand and legacy soils from a FFTA.

Per-and polyfluoroalkyl substances (PFAS) are manmade, fluorinated organic chemicals which have been identified as persistent organic pollutants. PFAS have surface active properties that have made them suitable for applications in oil-and water-resistant products, as well as many firefighting foams. No on-site remediation strategies exist to treat PFAS impacted soils. Mechanochemical remediation of PFOS-and PFOA-amended sand via a planetary ball mill was studied. The effect of sand mass, KOH as a co-milling reagent, and water saturation on the degradation of PFOA and PFOS was evaluated. By 4 h of milling concentrations were reduced by up to 98% for PFOS-amended dry sand and 99% for PFOA-amended dry sand without the addition of a co-milling reagent. Water saturation was determined to be a significant hindrance on the mechanochemical destruction of PFOS and PFOA. A maximum of 89% of fluoride was recovered from PFOS-amended sand when KOH was used as a co-milling reagent. It is hypothesized that reactive particles generated from the fracture of sand grains react with PFAS molecules to initiate destruction, which can result in full defluorination. Milling experiments were also conducted on soils from a Canadian firefighting training area (FFTA), demonstrating that PFOS concentrations can be reduced by up to 96% in site soils. For the first time, ball milling for the remediation of PFAS in environmental media has been demonstrated using amended sand and legacy soils from a FFTA.

Per uoroalkyl substances (PFAS) are highly persistent organic pollutants that have been detected in a wide array of environmental matrices and, in turn, biota including humans and wildlife wherein they have been associated with a multitude of toxic, and otherwise adverse effects, including ecosystem impacts. In the present study, we developed a toxicity assay for embryonic stages of mahi-mahi (Coryphaena hippurus), as an environmentally relevant pelagic sh species, and applied this assay to the evaluation of the toxicity of "legacy" and "next-generation" PFAS including, respectively, per uorooctanoic acid (PFOA) and several per uoroethercarboxylic acids (PFECA). Acute embryotoxicity, in the form of lethality, was measured for all ve PFAS toward mahi-mahi embryos with median lethal concentrations (LC 50) in the micromolar range. Consistent with studies in other similar model systems, and speci cally the zebra sh, embryotoxicity in mahi-mahi generally (1) correlated with uoroalkyl chain length and hydrophobicity, i.e., log P, of PFAS, and thus, aligned with a role of uptake in the relative toxicity; and (2) increased with continuous exposure, suggesting a possible role of developmental stage speci cally including a contribution of hatching (and loss of protective chorion) and/or differentiation of target systems (e.g., liver). Compared to prior studies in the zebra sh embryo model, mahi-mahi was signi cantly more sensitive to PFAS which may be related to differences in either exposure conditions (e.g., salinity) and uptake, or possibly differential susceptibility of relevant targets, for the two species. Moreover, when considered in the context of the previously reported concentration of PFAS within upper sea surface layers, and co-localization of buoyant eggs (i.e., embryos) and other early developmental stages (i.e., larvae, juveniles) of pelagic sh species to the sea surface, the observed toxicity potentially aligns with environmentally relevant concentrations in these marine systems. Thus, impacts on ecosystems including, in particular, population recruitment are a possibility. The present study is the rst to demonstrate embryotoxicity of PFAS in a pelagic marine sh species, and suggests that mahi-mahi represents a potentially informative, and moreover, environmentally relevant, ecotoxicological model for PFAS in marine systems.

Emerging chemical contaminants [e.g. toxic metals speciation, flame retardants (FRs) and perfluorinated compounds (PFCs), among others], that have not been historically recognized as pollutants nor their toxicological hazards, are increasingly more present in the marine environment. Furthermore, the effects of environmental conditions (e.g. temperature and pH) on bioaccumulation and elimination mechanisms of these emerging contaminants in marine biota have been poorly studied until now. In this context, the aim of this study was to assess, for the first time, the effect of warmer seawater temperatures (Δ = + 4°C) and lower pH levels (Δ = - 0.4 pH units), acting alone or combined, on the bioaccumulation and elimination of emerging FRs (dechloranes 602, 603 and 604, and TBBPA), inorganic arsenic (iAs), and PFCs (PFOA and PFOS) in two estuarine bivalve species (Mytilus galloprovincialis and Ruditapes philippinarum). Overall, results showed that warming alone or combined with acidificat...

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This article examines the tensions that arise when Patagonia simultaneously pursues sustainability and quality objectives embedded within its mission statement: "Build the best product, cause no unnecessary harm, use business to inspire and implement solutions to the environmental crisis." Specifically, this case study focuses on Patagonia's durable water repellent (DWR) problem. DWR is a highly effective chemical treatment used to waterproof jackets (supporting the quality objective) but has by-products that are toxic and persist in the environment (undermining the sustainability objective). This case explores the challenges Patagonia has faced and presents some creative solutions to them.

Perfluorinated compounds (PFCs) have been recognized as an important class of environmental contaminants commonly detected in blood samples of both wildlife and humans. These compounds have been in use for more than 60 years as surface treatment chemicals, polymerization aids, and surfactants. They possess a strong carbon-fluorine bond, which leads to their environmental persistence. There is evidence from both epidemiology and laboratory studies that PFCs may be immunotoxic, affecting both cell-mediated and humoral immunity. Reported effects of PFCs include decreased spleen and thymus weights and cellularity, reduced specific antibody production, reduced survival after influenza infection, and altered cytokine production. Immunosuppression is a critical effect associated with exposure to PFCs, as it has been reported to reduce antibody responses to vaccination in children. Mounting evidence suggests that immunotoxicity in experimental animals can occur at serum concentrations below...

The PREVIENI project (funded by the Ministry of Environment) investigated the exposure to endocrine disrupters in samples of human population and environmental biota in Italy. The environmental biomonitoring considered two Italian WWF Oasis, with the aim to compare the presence and effects of endocrine disruptors in organisms from two protected natural areas, respectively, upstream and downstream a chemical emission site. Chemical analysis of pollutants tissue levels was made on tissues from earthworm, barbell, trout, and coot, selected as bioindicator organisms. The contaminants considered were as follows: the perfluorinated compounds perfuoroctane sulfonate (PFOS) and perfluorooctanoic acid (PFOA), polychlorinated biphenyls (PCBs 58 congeners), polybrominated diphenyl ethers (PBDEs, 13 congeners), polycyclic aromatic hydrocarbons (PAHs, 16 compounds), toxic trace elements, the phthalate di-2-ethylexyl phthalate (DEHP) and its primary metabolite, bisphenol A, synthetic musk compounds (musk xylene, musk ketone, tonalide, and galaxolide), and p-nonylphenol. The analyses showed low concentrations of most pollutants in all species from both areas, compared to available literature; noticeable exceptions were the increases of DEHP's primary metabolite, PBDE, PAHs, Hg, and Pb in barbells, and of PCB and Cd in earthworms from the downstream area. The results showed the presence of endocrine disruptors, including those considered as Bnon-persistent,^in bioindicators from protected areas, albeit at low levels. The results provide a contribution to the evaluation of

This research investigated the spatial distribution of chemical contamination and toxicity of marine surfacial sediments collected from six sites along the Turkish coast in Black Sea. Sediment toxicity to sea urchin (Paracentrotus lividus) embryonic development was evaluated with whole sediment specimens. Concurrently, sediment samples were analyzed for their chemical characterisation to evaluate toxicity data.

Perfluoroalkyl substances (PFASs) are synthetic chemicals that are harmful to both the environment and human health. Using self-interaction-corrected Born-Oppenheimer molecular dynamics simulations, we provide the first real‐time assessment of PFAS degradation in the presence of excess electrons. In particular, we show that the initial phase of the degradation involves the transformation of an alkane-type C-C bond into an alkene-type C=C bond in the PFAS molecule, which is initiated by the trans elimination of fluorine atoms bonded to these adjacent carbon atoms.

Striped catfish (Pangasianodon hypophthalmus) is an economically important fish in Vietnam. The catfish fillets contain high fatty acid composition. The FABP family is involved in lipid transport and metabolism as well as in the regulation of gene expression and cell development. In this study, the catfish genome database was searched for fabp gene family; then, gene structure, classification and phylogenetic relationships were analyzed. In striped catfish genome, we found 10 fabp genes that are homologous to other fish species and other 5 novel fabp genes that have not been clearly annotated. These newly identified fabp genes cluster separately from the known members of the fabp family on the phylogenetic tree, and further studies are needed to understand their roles and functions. We examined transcriptional gene expression of fabp3, fabp7 and fabp10a genes in muscle, liver and brain tissues of the stripped catfish. The results showed that fabp10a gene was not strongly expressed i...

The chemical industry is a particularly sensitive sector that very often works with toxic, harmful and dangerous substances. This paper offers insight into the corporate socially responsible (CSR) behaviour of a specific segment of the chemical industry—the production of fluorinated ski waxes. Perfluorinated compounds, which excel in water and fat stability and repellency, are nowadays considered as harmful to human health and nature. During 2020, the basic compound, perfluorooctanoic acid (PFOA), will be banned, and finding its replacement will be a difficult task. So far, there are no alternatives in terms of environmentally friendly compounds that can maintain the desired properties of extreme ski glide. Based on a questionnaire distributed to twenty wax producers worldwide, we have concluded that, although the attitudes of companies towards CSR certification was rather negative (87.5%), and companies had not developed or documented any CSR policy/strategy with specific goals, th...

The PREVIENI project (funded by the Ministry of Environment) investigated the exposure to endocrine disrupters in samples of human population and environmental biota in Italy. The environmental biomonitoring considered two Italian WWF Oasis, with the aim to compare the presence and effects of endocrine disruptors in organisms from two protected natural areas, respectively, upstream and downstream a chemical emission site. Chemical analysis of pollutants tissue levels was made on tissues from earthworm, barbell, trout, and coot, selected as bioindicator organisms. The contaminants considered were as follows: the perfluorinated compounds perfuoroctane sulfonate (PFOS) and perfluorooctanoic acid (PFOA), polychlorinated biphenyls (PCBs 58 congeners), polybrominated diphenyl ethers (PBDEs, 13 congeners), polycyclic aromatic hydrocarbons (PAHs, 16 compounds), toxic trace elements, the phthalate di-2-ethylexyl phthalate (DEHP) and its primary metabolite, bisphenol A, synthetic musk compounds (musk xylene, musk ketone, tonalide, and galaxolide), and p-nonylphenol. The analyses showed low concentrations of most pollutants in all species from both areas, compared to available literature; noticeable exceptions were the increases of DEHP's primary metabolite, PBDE, PAHs, Hg, and Pb in barbells, and of PCB and Cd in earthworms from the downstream area. The results showed the presence of endocrine disruptors, including those considered as Bnon-persistent,^in bioindicators from protected areas, albeit at low levels. The results provide a contribution to the evaluation of

Livers of birds collected from Japan and Korea (n ¼ 83) were analyzed to determine the concentrations of perfluorooctanesulfonate (PFOS), perfluorooctanesulfonamide (FOSA), perfluorooctanoic acid (PFOA) and perfluorohexanesulfonate (PFHS). PFOS was found in the livers of 95% of the birds analyzed at concentrations greater than the limit of quantitation (LOQ) of 10 ng/g, wet weight. The greatest concentration of PFOS of 650 ng/g, wet weight, was found in the liver of a common cormorant from the Sagami River in Kanagawa Prefecture. Concentrations of PFOS in bird livers from Japan and Korea were within the ranges of values reported for those from the United States and certain European countries. PFOA and PFHS were found in 5-10% of the samples analyzed. The greatest concentrations of PFOA and PFHS in bird livers were 21 and 34 ng/g, wet weight, respectively. FOSA was found in all the samples (n ¼ 10) of cormorants collected from the Sagami River in Japan. The greatest concentration of FOSA in cormorant liver was 215 ng/g, wet weight. There was no significant correlation between the concentrations of PFOS and FOSA in cormorants collected from the Sagami River. These results suggested that the distribution of FOSA is localized. No ageor gender-specific differences in fluorochemical concentrations could be discerned in birds.

A challenge of in vitro to in vivo extrapolation (IVIVE) is to predict the physical state of organisms exposed to chemicals in the environment from in vitro exposure assay data. Although toxicokinetic modeling approaches promise to bridge in vitro screening data with in vivo effects, they are often encumbered by a need for redesign or re-parameterization when applied to different tissues or chemicals. We demonstrate a parameterization of reverse toxicokinetic (rTK) models developed for the adult zebrafish (Danio rerio) based upon particle swarm optimizations (PSO) of the chemical uptake and degradation rates that predict bioconcentration factors (BCF) for a broad range of chemicals. PSO reveals a relationship between chemical uptake and decomposition parameter values that predicts chemical-specific BCF values with moderate statistical agreement to a limited yet diverse chemical dataset, and all without a need to retrain the model to new data. The presented model requires only the oc...

Perfluorinated alkyl acids (PFAAs) are environmental contaminants that have been used in many products for over 50 years. Interest and concern has grown since 2000 on the widespread presence of PFAAs, when it was discovered that PFAAs were present in wildlife samples around the northern hemisphere. Since then, several studies have reported PFAAs in wildlife from many locations, including the remote regions of Antarctica and the Arctic. Although there are a multitude of studies, few have reported PFAA concentrations in reptiles and wildlife in the Southern Hemisphere. This study investigated the presence of PFAAs in the plasma of Nile crocodiles (Crocodylus niloticus) from South Africa. Crocodiles were captured from five sites in and around the Kruger National Park, South Africa, and plasma samples examined for PFAAs. Perfluorooctane sulfonate (PFOS) was the most frequent PFAA detected; with median values of 13.5 ng/g wet mass in crocodiles. In addition to PFOS, long chain perfluorinated carboxylic acids *

Background: Studies exploring the associations between perfluoroalkyl acids (PFAAs) and type 2 diabetes mellitus (T2DM) are rather limited and have reported conflicting results. All studies to date, including prospective ones, have relied on a single blood sample to study this association. Similarly, studies investigating how T2DM status may influence the longitudinal changes in PFAA concentrations have not been previously performed. As PFAA concentrations in humans have changed considerably over the last two decades, and as individuals diagnosed with T2DM usually undergo lifestyle changes that could influence these concentrations, a single blood sample may not necessarily reflect the lifetime exposure to PFAA concentrations. Hence, repeated measurements from the same individuals will extend our understanding of how PFAAs are associated with T2DM. The present study, therefore, aimed to explore associations between pre-and post-diagnostic PFAA blood profiles and T2DM and assess factors associated with longitudinal changes in PFAAs in T2DM cases and controls. Methods: Questionnaire data and blood samples from women participating in the Norwegian Women and Cancer study were used to conduct a nested case-control study among 46 T2DM cases matched to 85 non-diabetic controls. PFAAs were measured in blood samples collected prior to (2001/02) and after (2005/6) T2DM diagnosis. We investigated the association between PFAAs and incident and prevalent T2DM using conditional logistic regression. We assessed the longitudinal changes in PFAA concentrations within and between matched cases and controls using t-tests and linear regression models. Results: We observed no significant associations between pre-diagnostic PFAA concentrations and T2DM incidence. Similar results were observed for the post-diagnostic PFAA concentrations and T2DM prevalence. Decrease over time in PFAA concentrations were observed for PFOA and ∑PFOS concentrations, whereas increase over time were observed for PFNA, PFDA and PFUnDA concentrations. Longitudinal trends in PFAA concentrations among T2DM cases were similar to the changes observed in controls. Conclusions: The study did not find evidence of association between PFAAs and incident or prevalent T2DM. The longitudinal changes in PFAAs concentrations were not influenced by T2DM status.

Poly-and perfluoroalkyl substances are synthetic chemicals that are widely present in the global environment including the Arctic. However, little is known about how these chemicals (particularly perfluoroalkyl acids, PFAA) enter the Arctic marine system and cycle between seawater and sea ice compartments. To evaluate this, we analyzed sea ice, snow, melt ponds, and near-surface seawater at two ice-covered stations located north of the Barents Sea (81°N) with the aim of investigating PFAA dynamics in the late-season ice pack. Sea ice showed high concentrations of PFAA particularly at the surface with snow-ice (the uppermost sea ice layer strongly influenced by snow) comprising 26−62% of the total PFAA burden. Low salinities (<2.5 ppt) and low δ 18 O H20 values (<1‰ in snow and upper ice layers) in sea ice revealed the strong influence of meteoric water on sea ice, thus indicating a significant atmospheric source of PFAA with subsequent transfer down the sea ice column in meltwater. Importantly, the under-ice seawater (0.5 m depth) displayed some of the highest concentrations notably for the long-chain PFAA (e.g., PFOA 928 ± 617 pg L −1), which were ≈3-fold higher than those of deeper water (5 m depth) and ≈2-fold higher than those recently measured in surface waters of the North Sea infuenced by industrial inputs of PFAAs. The evidence provided here suggests that meltwater arising early in the melt season from snow and other surface ice floe components drives the higher PFAA concentrations observed in under-ice seawater, which could in turn influence the timing and extent of PFAA exposure for organisms at the base of the marine food web.

Moreton Bay is affected by a wide range of persistent pollutants, including the following four broad groups: (i) dioxins and persistent organic pollutants (POPs), (ii) trace elements (e.g. metals, metalloids and non-metals), (iii) perfluoroalkyl substances (PFAAs) and (iv) plastic-based marine debris. The pollutants discussed in this paper come from diverse chemical groups, and are similar in that they are persistent in the environment and impact the health of animals and/or humans. While most of these pollutants are banned and/or actively monitored by health organisations on a global scale, (e.g. PCBs and DDT) many are still entering our waterways daily (e.g. marine debris). We discuss how dioxins have impacted on the health, lifestyle, and culture of the region’s Traditional Custodians. Case studies are presented, highlighting the impacts of the four pollutant groups on marine megafauna found in Moreton Bay including sea turtles, seabirds, and stingrays. In all cases, the authors ...

Perfluorinated alkyl acids (PFAAs) are environmental contaminants that have been used in many products for over 50 years. Interest and concern has grown since 2000 on the widespread presence of PFAAs, when it was discovered that PFAAs were present in wildlife samples around the northern hemisphere. Since then, several studies have reported PFAAs in wildlife from many locations, including the remote regions of Antarctica and the Arctic. Although there are a multitude of studies, few have reported PFAA concentrations in reptiles and wildlife in the Southern Hemisphere. This study investigated the presence of PFAAs in the plasma of Nile crocodiles (Crocodylus niloticus) from South Africa. Crocodiles were captured from five sites in and around the Kruger National Park, South Africa, and plasma samples examined for PFAAs. Perfluorooctane sulfonate (PFOS) was the most frequent PFAA detected; with median values of 13.5 ng/g wet mass in crocodiles. In addition to PFOS, long chain perfluorinated carboxylic acids *

A comprehensive analysis of 15 target chemical compounds (pharmaceuticals and personal care product, perfluoroalkyl compounds and industrial chemicals) were carried out to determine their concentrations in selected commercially exploited, wild caught small and medium sized pelagic fish species and their organs (Thyrsites atun (snoek), Sarda orientalis (bonito), Pachymetopon blochii (panga) and Pterogymnus laniarius (hottentot)) obtained from Kalk Bay harbour, Cape Town. Solid phase extraction (SPE) method based on Oasis HLB cartridges were used to concentrate and clean-up the samples. Liquid chromatographyemass spectrometry analysis of these chemical compounds revealed the simultaneous presence of at least 12 compounds in different parts of the selected fish species in nanogram-per-gram dry weight (ng/g dw) concentrations. The results revealed that perfluorodecanoic acid, perfluorononanoic acid and perfluoroheptanoic acid were the most predominant among the perfluorinated compounds and ranged between: (20.13e179.2 ng/g), (21.22e114.0 ng/g) and (40.06e138.3 ng/g). Also, diclofenac had the highest concentration in these edible fish species out of all the pharmaceuticals detected (range: 551.8e1812 ng/g). The risk assessment values were above 0.5 and 1.0 for acute and chronic risk respectively which shows that these chemicals have a high health risk to the pelagic fish, aquatic organisms and to humans who consume them. Therefore, there is an urgent need for a precautionary approach and the adequate regulation of the use and disposal of synthetic chemicals that persist in aquatic/marine environment in this province and other parts of South Africa, to prevent impacts on the sustainability of our marine environment, livelihood and lives.