Exploration of the correlation of serum polychlorinated biphenyl levels with luteal phase hormonal parameters and infertility in women with or without polycystic ovary syndrome.

Introduction: Polychlorinated biphenyls (PCBs) are organic lipophilic pollutants that accumulate in the body. Previous research has linked PCBs with menstrual function; therefore, this study was undertaken to investigate the correlation of PCBs with luteal phase hormonal parameters of menstrual function at day 21 in a group of non-obese women prior to fertilization (IVF).

Methods: Fifty-eight non-obese Caucasian women from a UK academic center, 29 with polycystic ovary syndrome (PCOS) and 29 without, were recruited.

Serum polychlorinated biphenyl levels and circulating miRNAs in non-obese women with and without polycystic ovary syndrome.

Introduction: Polychlorinated biphenyls (PCBs), organic lipophilic pollutants that accumulate through diet and increase with age, have been associated with polycystic ovary syndrome (PCOS) and shown to affect microRNA (miRNA) expression. This work aimed to determine if PCBs were associated with circulating miRNAs and whether there were any correlations with serum PCB/miRNA levels and hormonal changes.

Methods: 29 non-obese PCOS and 29 healthy control women, with similar age and body mass index (BMI), had their serum miRNAs measured together with 7 indicator PCBs (PCB28, PCB52, PCB101, PCB118, PCB138, PCB153, PCB180) using high resolution gas chromatography coupled with high resolution mass spectrometry.

Persistent Organic Contaminants in Dust from the International Space Station.

Polybrominated diphenyl ethers (PBDEs), hexabromocyclododecane (HBCDD), "novel" brominated flame retardants (NBFRs), organophosphate esters (OPEs), polycyclic aromatic hydrocarbons (PAH), perfluoroalkyl substances (PFAS), and polychlorinated biphenyls (PCBs) were measured in a composite sample of dust from the International Space Station (ISS). Notwithstanding the unique environment from which the dust originated, while concentrations of all target compound classes frequently exceeded the median values in terrestrial indoor microenvironments in the US and western Europe, ISS dust concentrations were generally within the terrestrial range. The relative abundance of the three HBCDD diastereomers is dominated by γ-HBCDD (96.

Association of flame retardants, polybrominated diethyl ethers (PBDEs), with vitamin D in female subjects.

Introduction: A class of flame retardants, polybrominated diethyl ethers (PBDEs), are known endocrine disrupters and may induce the hepatic enzymes CYP24 and CYP3A that promote 25-hydroxylation of vitamin D. Therefore, this study examined the association of PBDEs with vitamin D (25(OH)D) and the active 1,25-dihydrovitamin D (1,25(OH)D) in a cohort of non-obese women.

Methods: 58 female participants (age:31.

Association of polychlorinated biphenyls with vitamin D in female subjects.

Introduction: Polychlorinated biphenyls (PCBs) are known endocrine disrupters. A potentially causal association of PCBs with vitamin D has been reported. Higher body mass index (BMI) is associated with lower PCB levels whilst the strongest association of PCBs with BMI is in non-obese individuals.

Association between Organochlorine Pesticides and Vitamin D in Female Subjects.

In human population studies, organochlorine pesticides (OCPs) have been linked to vitamin D deficiency. Therefore, this study examined the association between OCPs, vitamin D (cholecalciferol, 25(OH)D), and the active metabolite 1,25-dihydrovitamin D (1,25(OH)D) in a cohort of non-obese women. The serum samples of 58 female participants (age-31.

Rapid Determination of Selected PFAS in Textiles Entering the Waste Stream.

Due to new European legislation, products entering the waste stream containing some perfluoro alkyl substances (PFAS) are subject to "low persistent organic pollutant concentration limits". Concentrations of restricted PFAS must be below this limit for them to be legally recycled or disposed of. A rapid extraction and clean-up method was developed for the determination of 21 PFAS in various polymers used in soft furnishings and upholstery.

Elevated concentrations of halogenated flame retardants in waste childcare articles from Ireland.

Concentrations of legacy and alternative halogenated flame retardants (HFRs) including chlorinated organophosphate esters (Cl-OPEs), were measured in waste childcare articles (n = 275 for Cl-OPEs, n = 187 for other HFRs) from the Republic of Ireland between 2019 and 2020. Articles studied comprised foams and fabrics from: child car seats, cot mattresses, changing mats, pushchairs, prams, and related items. Fifteen articles (7.

Chlorinated organophosphate esters in Irish waste foams and fabrics: Concentrations, preliminary assessment of temporal trends and evaluation of the impact of a concentration limit value.

Concentrations of the chlorinated organophosphate esters (Cl-OPEs): tris(2-chloroethyl) phosphate (TCEP), tris(1-chloro-2-propyl) phosphate (TCIPP), and tris(1,3-dichloro-2-propyl) phosphate (TDCIPP) were measured in 273 waste synthetic foam and fabric articles collected in Ireland between 2019 and 2020. Articles examined comprised: polystyrene building insulation foam, as well as foam fillings and fabric coverings from furniture, mattresses, end-of-life vehicles, curtains, and carpets. Cl-OPEs were also measured in 156 samples from the same categories (except for building insulation foam) collected in 2015-16.

Single-cell multi-omics profiling links dynamic DNA methylation to cell fate decisions during mouse early organogenesis.

Background: Perturbation of DNA methyltransferases (DNMTs) and of the active DNA demethylation pathway via ten-eleven translocation (TET) methylcytosine dioxygenases results in severe developmental defects and embryonic lethality. Dynamic control of DNA methylation is therefore vital for embryogenesis, yet the underlying mechanisms remain poorly understood.

Results: Here we report a single-cell transcriptomic atlas from Dnmt and Tet mutant mouse embryos during early organogenesis.

POP-BFRs in consumer products: Evolution of the efficacy of XRF screening for legislative compliance over a 5-year interval and future trends.

In 2015-16, a study of approximately 500 waste plastic articles showed that portable X-ray fluorescence (XRF) was up to 95 % effective in screening for compliance with low persistent organic pollutant (POP) concentration limits (LPCLs) on brominated flame retardants (BFRs) in waste. The present study conducted in 2019-20 mirrors that conducted five years prior on a similar number and range of articles, testing the hypothesis that increased use of alternative BFRs as replacements for POP-BFRs will reduce the effectiveness of XRF as a tool for monitoring compliance with LPCLs. In comparing the results, the overall screening efficacy for LPCL compliance reduced from ~95 % to ~88 %, due in part to decreased prevalence of POP-BFRs and potentially increased presence of alternative flame retardants, particularly in goods with shorter lifecycles such as electronics.

A case-control study of polychlorinated biphenyl association with metabolic and hormonal outcomes in polycystic ovary syndrome.

Polychlorinated biphenyls (PCBs) are a class of environmental pollutants with a long half-life that sequester in fat. Women with polycystic ovarian syndrome (PCOS) may represent a sensitive subgroup to endogenous exposure to PCBs because of associated weight gain. Seven PCB congeners were compared in age, ethnicity, and BMI matched women with ( = 29) and without ( = 30) PCOS and related to metabolic outcomes, and steroid and thyroid hormone levels.

Halogenated flame retardants in Irish waste polymers: Concentrations, legislative compliance, and preliminary assessment of temporal trends.

Halogenated flame retardants (HFRs) were measured in 470 waste plastic articles from Ireland between 2019 and 2020. We identified articles containing concentrations of polybrominated diphenyl ethers (PBDEs), hexabromocyclododecane (HBCDD), and tetrabromobisphenol-A (TBBP-A) exceeding European Union limits. Enforcement of existing limits of 1000 mg/kg will render an estimated 3.

Exposure, risk and predictors of hexabromocyclododecane and Tetrabromobisphenol-A in house dust from urban, rural and E-waste dismantling sites in Thailand.

In this study, for the first time, we determined concentrations of hexabromocyclododecane (HBCDD) and tetrabromobisphenol-A (TBBPA) in house dust and estimated human exposure to these substances in houses located in an e-waste dismantling site and in urban and rural residential areas of Thailand. The median HBCDD concentration in urban residential houses (2.10 ng g) was similar to that in houses in an e-waste dismantling site (2.

Maternal Dppa2 and Dppa4 are dispensable for zygotic genome activation but important for offspring survival.

Zygotic genome activation (ZGA) represents the initiation of transcription following fertilisation. Despite its importance, we know little of the molecular events that initiate mammalian ZGA in vivo. Recent in vitro studies in mouse embryonic stem cells have revealed developmental pluripotency associated 2 and 4 (Dppa2/4) as key regulators of ZGA-associated transcription.

Comparison of lipid-normalised concentrations of persistent organic pollutants (POPs) between serum and adipose tissue.

Human biomonitoring of persistent organic pollutants (POPs) is typically based on serum analysis and for comparison and modelling purposes, data are often normalised to the lipid content of the serum. Such approach assumes a steady state of the compound between the serum lipids and for example lipid-rich adipose tissue. Few published data are available to assess the validity of this assumption.

Interspecies comparisons of brominated flame retardants in relation to foraging ecology and behaviour of gulls frequenting a UK landfill.

This study quantifies and compares concentrations and profiles of legacy and alternative (alt-) brominated flame retardants (BFRs) in the eggs of three gull (Laridae) species of international/UK conservation concern - great black-backed gulls (Larus marinus; n = 7), European herring gulls (L. argentatus; n = 16) and lesser black-backed gulls (L. fuscus; n = 11) in relation to their foraging ecology and behaviour in order to investigate potential exposure pathways at a remote landfill in western Scotland, UK.

Phasing-out of legacy brominated flame retardants: The UNEP Stockholm Convention and other legislative action worldwide.

Due to their toxicity and persistence, several families of brominated flame retardants (BFRs) have been listed as persistent organic pollutants (POPs) in the Stockholm Convention, a multilateral treaty overseen by the United Nations Environment Programme. This treaty mandates that parties who have signed must take administrative and legislative actions to prevent the environmental impacts that POPs pose, both within their jurisdictions and in the global environment. The specific BFRs listed in the Stockholm Convention are Polybrominated Diphenyl Ethers (PBDEs), Hexabromocyclododecane (HBCDD), and Hexabromobiphenyl (HBB), chemicals which must therefore be heavily restricted within the jurisdictions of the signatories.

Children's exposure to hazardous brominated flame retardants in plastic toys.

We report concentrations of brominated flame retardants (BFRs) in 23 plastic samples from 20 new and second-hand children's toys sourced from the UK that had been previously shown to be Br-positive by XRF. The results reinforce existing evidence that the recycling of BFR-treated electronic plastics has led to the unintentional BFR contamination of articles not required to be flame-retarded. The principal BFRs detected were PBDEs (and in particular BDE-209), HBCDD and TBBP-A.

Perfluoroalkyl substances and brominated flame retardants in landfill-related air, soil, and groundwater from Ireland.

Between November 2018 and January 2019, samples of air and soil were collected from locations downwind and upwind of 10 landfills across the Republic of Ireland. Samples of groundwater (n = 10) were also collected from locations with links traceable to the studied landfills. Concentrations of perfluoroalkyl substances (PFASs), polybrominated diphenyl ethers (PBDEs), hexabromocyclodecane (HBCDD), and decabromodiphenyl ethane (DBDPE) determined in air and soil samples were not significantly different (p > 0.

Concentrations of perfluoroalkyl substances in human milk from Ireland: Implications for adult and nursing infant exposure.

Concentrations of 10 perfluoroalkyl substances (PFASs) were measured in 16 pools of human milk from Ireland. Only four PFASs were detected (PFOA, PFNA, PFHxS and PFOS), with concentrations dominated by PFOA which was detected in all samples at a median of 0.10 ng/mL.

Perfluoroalkyl Substances in Drinking Water, Indoor Air and Dust from Ireland: Implications for Human Exposure.

Perfluoroalkyl substances (PFASs) were measured in air and dust from cars, homes, offices, and school classrooms in Ireland, along with drinking water from homes and offices. Perfluorooctanoic acid (PFOA) dominated air and drinking water, while perfluorobutane sulfonate (PFBS) dominated dust. This is the first report of PFOA, perfluorooctane sulfonate (PFOS), perfluorohexane sulfonate (PFHxS), PFBS, and perfluorononanoic acid (PFNA) in air inside cars and school classrooms.

Differential Sperm Motility Mediates the Sex Ratio Drive Shaping Mouse Sex Chromosome Evolution.

The mouse sex chromosomes exhibit an extraordinary level of copy number amplification of postmeiotically expressed genes [1, 2], driven by an "arms race" (genomic conflict) between the X and Y chromosomes over the control of offspring sex ratio. The sex-linked ampliconic transcriptional regulators Slx and Sly [3-7] have opposing effects on global transcription levels of the sex chromosomes in haploid spermatids via regulation of postmeiotic sex chromatin (PMSC) [8-11] and opposing effects on offspring sex ratio. Partial deletions of the Y chromosome (Yq) that reduce Sly copy number lead to global overexpression of sex-linked genes in spermatids and either a distorted sex ratio in favor of females (smaller deletions) or sterility (larger deletions) [12-16].

Emerging and legacy brominated flame retardants in the breast milk of first time Irish mothers suggest positive response to restrictions on use of HBCDD and Penta- and Octa-BDE formulations.

The brominated flame retardants (BFRs) hexabromocyclododecane (HBCDD), eight polybrominated diphenyl ethers (PBDEs), and decabromodiphenyl ethane (DBDPE) were measured in 16 pools of human milk from Ireland. Concentrations of BDEs-47, -99, -100, -153, and HBCDD were significantly lower (p < 0.05) than those in Irish human milk collected in 2011.