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Journal of Chromatography. A May 2024Birds are excellent bioindicators of environmental pollution, and blood provides information on contaminant exposure, although its analysis is challenging because of the...
Optimization and uncertainty assessment of a gas chromatography coupled to Orbitrap mass spectrometry method to determine organic contaminants in blood: A case study of an endangered seabird.
Birds are excellent bioindicators of environmental pollution, and blood provides information on contaminant exposure, although its analysis is challenging because of the low volumes that can be sampled. The objective of the present study was to optimize and validate a miniaturized and functional extraction and analytical method based on gas chromatography coupled to Orbitrap mass spectrometry (GCOrbitrap-MS) for the trace analysis of contaminants in avian blood. Studied compounds included 25 organochlorine pesticides (OCPs), 6 polychlorinated biphenyls (PCBs), 8 polybrominated diphenyl ethers (PBDEs) and 15 polycyclic aromatic hydrocarbons (PAHs). Four extraction and clean-up conditions were optimized and compared in terms of efficiency, accuracy, and uncertainty assessment. Extraction with hexane:dichloromethane and miniaturized Florisil pipette clean-up was the most adequate considering precision and accuracy, time, and costs, and was thereafter used to analyse 20 blood samples of a pelagic seabird, namely the Bermuda petrel (Pterodroma cahow). This species, endemic to the Northwest Atlantic, is among the most endangered seabirds of the region that in the '60 faced a decrease in the breeding success likely linked to a consistent exposure to dichloro-diphenyl-trichloroethane (DDT). Indeed, p,p'-DDE, the main DDT metabolite, was detected in all samples and ranged bewteen 1.13 and 6.87 ng/g wet weight. Other ubiquitous compounds were PCBs (ranging from 0.13 to 6.76 ng/g ww), hexachlorobenzene, and mirex, while PAHs were sporadically detected at low concentrations, and PBDEs were not present. Overall, the extraction method herein proposed allowed analysing very small blood volumes (∼ 100 µL), thus respecting ethical principles prioritising the application of less-invasive sampling protocols, fundamental when studying threatened avian species.
Topics: Animals; Gas Chromatography-Mass Spectrometry; Pesticides; Birds; Hydrocarbons, Chlorinated; Polychlorinated Biphenyls; Halogenated Diphenyl Ethers; Polycyclic Aromatic Hydrocarbons; Endangered Species; Environmental Monitoring; Environmental Pollutants
PubMed: 38604058
DOI: 10.1016/j.chroma.2024.464870 -
Chemosphere May 2023In support of the United Nations Environment Programme (UNEP) global monitoring plan under the Stockholm Convention concentrations of persistent organic pollutants...
In support of the United Nations Environment Programme (UNEP) global monitoring plan under the Stockholm Convention concentrations of persistent organic pollutants (POPs) were determined during two years in air from 42 countries in Asia, Africa, Latin America, and the Pacific by using polyurethane foams installed in passive samplers. The compounds included were polychlorinated biphenyls (PCBs), organochlorine pesticides (OCPs), polybrominated diphenylethers (PBDEs), one polybrominated biphenyl and hexabromocyclododecane (HBCD) diastereomers. Total-DDT and PCBs were the highest in concentrations in about 50% of the samples, which shows their high persistency. Total DDT in air from the Solomon Islands ranged from 200 to 600 ng/polyurethane foam disk (PUF). However, at most locations, a decreasing trend is observed for PCBs, DDT and most other OCPs. Patterns varied per country with e.g. elevated dieldrin in air from Barbados and chlordane in air from the Philippines. A number of OCPs, such as heptachlor and its epoxides, some other chlordanes, mirex and toxaphene have decreased down to almost undetectable levels. PBB153 was hardly found and penta and octa--mix related PBDEs were also relatively low at most locations. HBCD and the decabromodiphenylether were more prominent at many locations and may even still increase. To draw more holistic conclusions more colder climate countries should be included in this program.
Topics: Polychlorinated Biphenyls; Persistent Organic Pollutants; DDT; Halogenated Diphenyl Ethers; Latin America; Environmental Monitoring; Air Pollutants; Hydrocarbons, Chlorinated; Pesticides; Chlordan; Africa
PubMed: 36878366
DOI: 10.1016/j.chemosphere.2023.138271 -
PloS One 2015Endocrine-disrupting chemicals (EDCs) adversely affect human health. Our objective was to determine the association of EDC exposure with earlier age of menopause.
OBJECTIVE
Endocrine-disrupting chemicals (EDCs) adversely affect human health. Our objective was to determine the association of EDC exposure with earlier age of menopause.
METHODS
Cross-sectional survey using National Health and Nutrition Examination Survey (NHANES) data from 1999 to 2008 (n = 31,575 females). Eligible participants included: menopausal women >30 years of age; not currently pregnant, breastfeeding, using hormonal contraception; no history of bilateral oophorectomy or hysterectomy. Exposures, defined by serum lipid and urine creatinine-adjusted measures of EDCs, data were analyzed: > 90th percentile of the EDC distribution among all women, log-transformed EDC level, and decile of EDC level. Multi linear regression models considered complex survey design characteristics and adjusted for age, race/ethnicity, smoking, body mass index. EDCs were stratified into long (>1 year), short, and unknown half-lives; principle analyses were performed on those with long half-lives as well as phthalates, known reproductive toxicants. Secondary analysis determined whether the odds of being menopausal increased with EDC exposure among women aged 45-55 years.
FINDINGS
This analysis examined 111 EDCs and focused on known reproductive toxicants or chemicals with half-lives >1 year. Women with high levels of β-hexachlorocyclohexane, mirex, p,p'-DDE, 1,2,3,4,6,7,8-heptachlorodibenzofuran, mono-(2-ethyl-5-hydroxyhexyl) and mono-(2-ethyl-5-oxohexyl) phthalate, polychlorinated biphenyl congeners -70, -99, -105, -118, -138, -153, -156, -170, and -183 had mean ages of menopause 1.9 to 3.8 years earlier than women with lower levels of these chemicals. EDC-exposed women were up to 6 times more likely to be menopausal than non-exposed women.
CONCLUSIONS
This study of a representative sample of US women documents an association between EDCs and earlier age at menopause. We identified 15 EDCs that warrant closer evaluation because of their persistence and potential detrimental effects on ovarian function. Earlier menopause can alter the quantity and quality of a woman's life and has profound implications for fertility, human reproduction, and our global society.
Topics: Adult; Aged; Cross-Sectional Studies; Databases, Factual; Endocrine Disruptors; Environmental Pollutants; Female; Humans; Menopause, Premature; Middle Aged; Organic Chemicals; Public Health Surveillance; Reproduction; Risk Factors; United States
PubMed: 25629726
DOI: 10.1371/journal.pone.0116057 -
Heliyon Sep 2021The characterization of the population exposed to pesticides and the use of effective biomarkers to evaluate potential health effects are determinant to identify...
The characterization of the population exposed to pesticides and the use of effective biomarkers to evaluate potential health effects are determinant to identify vulnerable groups, understanding the causality of diverse pathologies and propose prevention policies. This is particularly important in countries where intensive agricultural practices had an explosive expansion in last decades. The aim of this study was assessing the usefulness of two exposure indexes questionnaire-based: Intensity Level of the pesticide Exposure (ILE) and Cumulative Exposure Index (CEI) and their scales, in terrestrial applicators of pesticide from the Province of Córdoba (Argentina). The analysis was performed contrasting ILE and CEI results with perceived symptomatology, in addition to effect and exposure biomarkers. A cross-sectional study was designed to compare pesticides body burdens and effect biomarkers between subjects occupationally (OE) and non-occupationally exposed (NOE) to pesticides. Prevalence of perceived symptomatology and genotoxicity damage was higher in the OE group. The exposure condition was the only variable explaining these differences. Significant associations were found between CEI and neurologic symptomatology (p < 0.05) and between ILE and plasmatic cholinesterase (p < 0.1). However, residues of HCB, β-HCH, α-endosulfan, pp'DDE, endrin, β-endosulfan, pp'DDT, endosulfan sulfate and mirex were found in blood samples from both groups. To our knowledge, this is the first report on pesticides body burdens in occupational exposure settings in Argentina. So far, our current results indicate that the occupational condition affects the health of the workers. Significant associations found between symptomatology and biomarkers with scales of CEI and ILE suggest their usefulness to verify different levels of exposure. Further research is necessary to propose these indexes as an affordable tool for occupational health surveillance in areas with difficult access to health care centres.
PubMed: 34522813
DOI: 10.1016/j.heliyon.2021.e07921 -
Cell Reports Apr 2023In metazoan cells, DNA replication initiates from thousands of genomic loci scattered throughout the genome called DNA replication origins. Origins are strongly...
In metazoan cells, DNA replication initiates from thousands of genomic loci scattered throughout the genome called DNA replication origins. Origins are strongly associated with euchromatin, particularly open genomic regions such as promoters and enhancers. However, over a third of transcriptionally silent genes are associated with DNA replication initiation. Most of these genes are bound and repressed by the Polycomb repressive complex-2 (PRC2) through the repressive H3K27me3 mark. This is the strongest overlap observed for a chromatin regulator with replication origin activity. Here, we asked whether Polycomb-mediated gene repression is functionally involved in recruiting DNA replication origins to transcriptionally silent genes. We show that the absence of EZH2, the catalytic subunit of PRC2, results in increased DNA replication initiation, specifically in the vicinity of EZH2 binding sites. The increase in DNA replication initiation does not correlate with transcriptional de-repression or the acquisition of activating histone marks but does correlate with loss of H3K27me3 from bivalent promoters.
Topics: Animals; Histones; Enhancer of Zeste Homolog 2 Protein; Polycomb Repressive Complex 2; Chromatin; DNA Replication; DNA
PubMed: 36995935
DOI: 10.1016/j.celrep.2023.112280 -
BMC Plant Biology Jun 2015MicroRNAs are the key post-transcriptional regulators of gene expression in development and stress responses. Thus, precisely quantifying the level of each particular...
BACKGROUND
MicroRNAs are the key post-transcriptional regulators of gene expression in development and stress responses. Thus, precisely quantifying the level of each particular microRNA is of utmost importance when studying the biology of any organism.
DESCRIPTION
The mirEX 2.0 web portal ( http://www.combio.pl/mirex ) provides a comprehensive platform for the exploration of microRNA expression data based on quantitative Real Time PCR and NGS sequencing experiments, covering various developmental stages, from wild-type to mutant plants. The portal includes mature and pri-miRNA expression levels detected in three plant species (Arabidopsis thaliana, Hordeum vulgare and Pellia endiviifolia), and in A. thaliana miRNA biogenesis pathway mutants. In total, the database contains information about the expression of 461 miRNAs representing 268 families. The data can be explored through the use of advanced web tools, including (i) a graphical query builder system allowing a combination of any given species, developmental stages and tissues, (ii) a modular presentation of the results in the form of thematic windows, and (iii) a number of user-friendly utilities such as a community-building discussion system and extensive tutorial documentation (e.g., tooltips, exemplary videos and presentations). All data contained within the mirEX 2.0 database can be downloaded for use in further applications in a context-based way from the result windows or from a dedicated web page.
CONCLUSIONS
The mirEX 2.0 portal provides the plant research community with easily accessible data and powerful tools for application in multi-conditioned analyses of miRNA expression from important plant species in different biological and developmental backgrounds.
Topics: Arabidopsis; Databases, Nucleic Acid; Gene Expression Profiling; Hepatophyta; Hordeum; Internet; MicroRNAs; RNA, Plant; Real-Time Polymerase Chain Reaction
PubMed: 26141515
DOI: 10.1186/s12870-015-0533-2 -
Are Fish Consumption Advisories for the Great Lakes Adequately Protective against Chemical Mixtures?Environmental Health Perspectives Apr 2017The North American Great Lakes are home to > 140 types of fish and are famous for recreational and commercial fishing. However, the presence of toxic substances has...
BACKGROUND
The North American Great Lakes are home to > 140 types of fish and are famous for recreational and commercial fishing. However, the presence of toxic substances has resulted in the issuance of fish consumption advisories that are typically based on the most restrictive contaminant.
OBJECTIVES
We investigated whether these advisories, which typically neglect the existence of a mixture of chemicals and their possible additive adverse effects, are adequately protective of the health of humans consuming fish from the Canadian waters of the Great Lakes.
METHODS
Using recent fish contaminant monitoring data collected by the government of Ontario, Canada, we simulated advisories using most-restrictive-contaminant (one-chem) and multi-contaminant additive effect (multi-chem) approaches. The advisories from the two simulations were compared to determine if there is any deficiency in the currently issued advisories.
RESULTS
Approximately half of the advisories currently issued are potentially not adequately protective. Of the four Great Lakes studied, the highest percentage of advisories affected are in Lake Ontario if an additive effect is considered. Many fish that are popular for consumption, such as walleye, salmon, bass and trout, would have noticeably more stringent advisories.
CONCLUSIONS
Improvements in the advisories may be needed to ensure that the health of humans consuming fish from the Great Lakes is protected. In this region, total polychlorinated biphenyls (PCBs) and mercury are the major contaminants causing restrictions on consuming fish, whereas dioxins/furans, toxaphene, and mirex/photomirex are of minor concern. Regular monitoring of most organochlorine pesticides and metals in fish can be discontinued.
Topics: Animals; Canada; Consumer Advocacy; Diet; Dioxins; Environmental Exposure; Environmental Policy; Fishes; Food Contamination; Great Lakes Region; Humans; Mercury; Water Pollutants, Chemical; Water Pollution, Chemical
PubMed: 27697747
DOI: 10.1289/EHP104 -
Environmental Pollution (Barking, Essex... Sep 2016Seabirds play an important role as top consumers in the food web and can be used as biomonitors of exposure to pollutants. Contamination studies involving...
Seabirds play an important role as top consumers in the food web and can be used as biomonitors of exposure to pollutants. Contamination studies involving non-destructive sampling methods are of considerable importance, allowing better evaluation of the levels of pollutants and their toxic effects. In the present study, organohalogen contaminants were analyzed in 113 blood samples from Southern Giant Petrel (Macronectes giganteus) adults and chicks collected in the austral summer of 2011/2012 and 2012/2013 from colonies on Elephant and Livingston Islands, South Shetland, Antarctica. Polychlorinated biphenyls (PCBs), hexachlorobenzene (HCB), pentachlorobenzene (PeCB), mirex, dichlorodiphenyltrichloroetane and derivatives (DDTs) and chlordanes were detected in all birds, whereas polybrominated diphenyl ethers (PBDEs) were not detected in any blood samples. No significant differences were found in organochlorine levels between sampling events. Adults exhibited significantly higher levels than chicks, except for PeCB. PCBs, HCB, mirex and DDTs were statistically similar in males and females from Elephant Island. Females on Livingston Island exhibited higher HCB values than males, but no sex differences were found regarding other organochlorines. The similarity in organochlorine levels between sexes in birds with very marked sexual segregation in feeding habits during the breeding season may indicate that significant amounts of contaminants are acquired during migration to lower latitudes, when the diets of males and females are similar. Birds sampled on Livingston Island exhibited significantly lower levels of PCBs, HCB, DDTs, mirex and chlordanes in comparison to those on Elephant Island, which could be the result of distinct foraging patterns between the two colonies. Organochlorine levels were similar between years in birds captured in two consecutive breeding seasons. Blood samples from Southern Giant Petrels adults and chicks proved to be useful for the comparison of intraspecific contamination levels and appear to be adequate for the long-term assessment of organohalogen contaminants in antarctic top predators. Organochlorine contaminants in blood samples of Southern Giant Petrels reflected intra-specific differences and suggested distinct foraging patterns between colonies.
Topics: Animals; Antarctic Regions; Birds; Environmental Monitoring; Female; Food Chain; Hydrocarbons, Halogenated; Islands; Male; Water Pollutants, Chemical
PubMed: 27235927
DOI: 10.1016/j.envpol.2016.05.041 -
Environmental Research Mar 2020Although some persistent organic pollutants (POPs) are considered human carcinogens, results from studies evaluating exposures and breast cancer risk have been...
INTRODUCTION
Although some persistent organic pollutants (POPs) are considered human carcinogens, results from studies evaluating exposures and breast cancer risk have been inconsistent, potentially related to varying ages at exposure. Additionally, few studies evaluated the association between POPs exposure and mammographic breast density (MBD), an intermediate biomarker of breast cancer risk. We carried out a cross-sectional study to investigate associations between serum POPs concentrations and MBD measured in 1998 in female residents of Triana, Alabama, in a predominately African American population with high POPs exposures, particularly to p,p'-DDT (1,1,1-trichloro-2,2-bis(p-chlorophenyl)ethane).
METHODS
We measured lipid-adjusted serum concentrations (ng/g lipid) of p,p'-DDT and its main metabolite p,p'-DDE (1,1-dichloro-2,2-bis(p-chlorophenyl)ethylene), polychlorinated biphenyls (PCBs), β-hexachlorocyclohexane (β-HCCH), heptachlor epoxide, oxychlordane, trans-nonachlor, mirex, and aldrin for each woman in our study (n = 210). We also measured two MBD metrics, percent MBD (%MBD) and area of MBD (aMBD). Using adjusted Spearman correlation coefficients (r) we evaluated correlations between %MBD and aMBD with individual POPs in the overall population and by age group (19-40, 41-54, and 55-91 years) and also estimated adjusted mean measures of MBD with 95% confidence intervals across tertiles of analytes using generalized linear models (GLM). We calculated p-values for multiplicative interaction by age group using GLM. Additional analyses excluded women with current hormone replacement therapy (HRT) use and evaluated early-life exposure (prior to age 18) during the heaviest contamination period in Triana (1947-90).
RESULTS
Among all women, we found no correlation between p,p'-DDE and %MBD, but after age stratification and exclusion of HRT users, there was a suggestion of a difference by age group, with younger women having a weak positive correlation (r = 0.12, p = 0.37) and older women having a weak negative correlation (r = -0.12, p = 0.43); p = 0.06. In contrast, PCBs were weakly positively correlated with %MBD among all women, with the correlation magnitudes increasing after excluding current HRT users (r = 0.17, p = 0.03). After age stratification and exclusion of HRT users, correlations for PCBs were higher among younger and middle-age women, with only a handful of these correlations being statistically significant. For β-HCCH, the strongest finding was a negative correlation among older women (r = -0.26, p = 0.07). Correlations were positive predominantly in the younger age group for heptachlor epoxide (r = 0.27, p = 0.04), oxychlordane (r = 0.35, p = 0.006), and trans-nonachlor (r = 0.37, p = 0.003), and largely null for the middle and older age groups; p range: 0.03-0.05. Similar patterns were found in GLM analyses using tertiles of exposure and aMBD as the metric for MBD. Women exposed during the heaviest chemical contamination period in Triana prior to age 18 had positive correlations between %MBD and PCBs, heptachlor epoxide, mirex, oxychlordane, and trans-nonachlor.
CONCLUSIONS
In this population, despite high exposures to p,p'-DDT and thus high serum concentrations of its main metabolite, p,p'-DDE, we did not find strong evidence of a positive association with MBD. In fact, there was some evidence of a negative association among older women for p,p'-DDE; a similar pattern was found for β-HCCH. However, younger women with higher serum levels of PCBs, heptachlor epoxide, oxychlordane, and trans-nonachlor, who were likely exposed in early life, had higher MBD. These findings should be replicated in larger studies.
Topics: Aged; Alabama; Breast Density; Cross-Sectional Studies; Dichlorodiphenyl Dichloroethylene; Environmental Pollutants; Female; Humans; Hydrocarbons, Chlorinated; Middle Aged; Polychlorinated Biphenyls
PubMed: 31918312
DOI: 10.1016/j.envres.2019.109068 -
Chemosphere Feb 2023Human breast milk reflects body burden of chemicals and has been used for exposure assessment to estimate risks of humans from pollutants. Harmonized protocols for...
Human breast milk reflects body burden of chemicals and has been used for exposure assessment to estimate risks of humans from pollutants. Harmonized protocols for sampling and analysis of persistent organic pollutants (POPs) have become widely available after the entry-into-force of the Stockholm Convention on POPs and activities coordinated by the United Nations Environment Programme (UNEP). These protocols promote the generation of national pools consisting of breast milk from first mothers directed to assess at national level but have not been assessed comprehensively. Early surveys date back to the mid-1980s, but the majority of the pools and high numbers of POPs analytes were available after the year 2000. Our assessment of pools from 90 countries for 29 POPs showed declining time trends for almost all POPs and significant differences between all 5-year time periods. However, in general, the most recent data from samples collected between 2015 and 2019, were no longer different from the period immediately prior. The strongest declines were seen for POPs that have already been measured for more than 30 years, i.e., dioxin-like POPs and polychlorinated biphenyls (PCB). For certain initial and newly listed POPs, such as aldrin, endrin, mirex, toxaphene, α-HCH, chlordecone, endosulfan, pentachlorobenzene, hexachlorobutadiene, decabromo diphenyl ether, hexabromobiphenyl 153, and perfluorohexane sulfonate, the median values in pools were always zero, and some of them were never quantified in these human milk pools. Since these POPs may be present at national level, we recommend including all listed POPs into surveys related to the Stockholm Convention.
Topics: Female; Humans; Persistent Organic Pollutants; Milk, Human; Environmental Monitoring; Environmental Pollutants; Polychlorinated Biphenyls
PubMed: 36513202
DOI: 10.1016/j.chemosphere.2022.137484