-
Chemical Research in Toxicology Feb 2024Exposure to environmental pollutants is linked to numerous toxic outcomes, warranting concern about the effect of pollutants on human health. To assess the threat of...
Exposure to environmental pollutants is linked to numerous toxic outcomes, warranting concern about the effect of pollutants on human health. To assess the threat of pollutant exposure, it is essential to understand their biological activity. Unfortunately, gaps remain for many pollutants' specific biological activity and molecular targets. A superfamily of signaling proteins, G-protein-coupled receptors (GPCRs), has been shown as potential targets for pollutant activity. However, research investigating the pollutant activity at the GPCRome is scarce. This work explores pollutant activity across a library of human GPCRs by leveraging modern high-throughput screening techniques devised for drug discovery and pharmacology. We designed and implemented a pilot screen of eight pollutants at 314 human GPCRs and discovered specific polychlorinated biphenyl (PCB) activity at sphingosine-1-phosphate and melatonin receptors. The method utilizes open-source resources available to academic and governmental institutions to enable future campaigns that screen large numbers of pollutants. Thus, we present a novel high-throughput approach to assess the biological activity and specific targets of pollutants.
Topics: Humans; Environmental Pollutants; Polychlorinated Biphenyls; Melatonin; Sphingosine-1-Phosphate Receptors; Receptors, G-Protein-Coupled
PubMed: 38295294
DOI: 10.1021/acs.chemrestox.3c00388 -
Biomedical Microdevices Jan 2024Direct 3D printing of active microfluidic elements on PCB substrates enables high-speed fabrication of stand-alone microdevices for a variety of health and energy...
Direct 3D printing of active microfluidic elements on PCB substrates enables high-speed fabrication of stand-alone microdevices for a variety of health and energy applications. Microvalves are key components of microfluidic devices and liquid metal (LM) microvalves exhibit promising flow control in microsystems integrated with PCBs. In this paper, we demonstrate LM microvalves directly 3D printed on PCB using advanced digital light processing (DLP). Electrodes on PCB are coated by carbon ink to prevent alloying between gallium-based LM plug and copper electrodes. We used DLP 3D printers with in-house developed acrylic-based resins, Isobornyl Acrylate, and Diurethane Dimethacrylate (DUDMA) and functionalized PCB surface with acrylic-based resin for strong bonding. Valving seats are printed in a 3D caterpillar geometry with chamber diameter of 700 µm. We successfully printed channels and nozzles down to 90 µm. Aiming for microvalves for low-power applications, we applied square-wave voltage of 2 V at a range of frequencies between 5 to 35 Hz. The results show precise control of the bistable valving mechanism based on electrochemical actuation of LMs.
Topics: Microfluidics; Polychlorinated Biphenyls; Catheters; Metals; Alloys
PubMed: 38289398
DOI: 10.1007/s10544-024-00697-z -
Toxics Dec 2023Polychlorinated biphenyls (PCBs) are persistent organic pollutants and endocrine disruptors that have been implicated in potential damage to human semen. However, the...
Polychlorinated biphenyls (PCBs) are persistent organic pollutants and endocrine disruptors that have been implicated in potential damage to human semen. However, the studies conducted so far provide contrasting results. Our study aimed to investigate the associations between PCB serum and semen levels and semen quality in high school and university students living in a highly PCB-polluted area of Italy. Subjects with a normal body mass index who did not make daily use of tobacco, alcohol, drugs, or medication were selected. All participants provided a fasting blood and a semen sample. Gas chromatography-mass spectrometry was used to determine the concentrations of 26 PCB congeners. The concentrations of PCB functional groups and total PCBs were also computed. A total of 143 subjects (median age 20, range 18-22 years) were enrolled. The median total PCB concentrations were 3.85 ng/mL (range 3.43-4.56 ng/mL) and 0.29 ng/mL (range 0.26-0.32 ng/mL) in serum and semen, respectively. The analysis of the associations between sperm PCB concentration and semen parameters showed (a) negative associations between some PCB congeners, functional groups and total PCBs and sperm total motility; (b) negative associations of total PCBs with sperm normal morphology; and (c) no association of PCBs with sperm concentration. Subjects at the highest quartile of semen total PCB concentration had 19% and 23% mean reductions in total motility and normal morphology, respectively, compared to those at the lowest quartile. The analysis of the associations of serum PCB levels with sperm parameters yielded null or mixed (some positive, other negative) results. In conclusion, the present study provides evidence of a negative effect of some PCB congeners and total PCBs in semen on sperm motility and normal morphology. However, the associations between the concentration of serum and semen PCB congeners and functional groups and sperm quality parameters were inconsistent.
PubMed: 38276719
DOI: 10.3390/toxics12010006 -
Journal of Hazardous Materials Mar 2024This review provides a comprehensive overview of the occurrence, fate, treatment and multi-criteria analysis of microplastics (MPs) and organic contaminants (OCs) in... (Meta-Analysis)
Meta-Analysis Review
This review provides a comprehensive overview of the occurrence, fate, treatment and multi-criteria analysis of microplastics (MPs) and organic contaminants (OCs) in biosolids. A meta-analysis was complementarily analysed through the literature to map out the occurrence and fate of MPs and 10 different groups of OCs. The data demonstrate that MPs (54.7% occurrence rate) and linear alkylbenzene sulfonate surfactants (44.2% occurrence rate) account for the highest prevalence of contaminants in biosolids. In turn, dioxin, polychlorinated biphenyls (PCBs) and phosphorus flame retardants (PFRs) have the lowest rates (<0.01%). The occurrence of several OCs (e.g., dioxin, per- and polyfluoroalkyl substances, polycyclic aromatic hydrocarbons, pharmaceutical and personal care products, ultraviolet filters, phosphate flame retardants) in Europe appear at higher rates than in Asia and the Americas. However, MP concentrations in biosolids from Australia are reported to be 10 times higher than in America and Europe, which required more measurement data for in-depth analysis. Amongst the OC groups, brominated flame retardants exhibited exceptional sorption to biosolids with partitioning coefficients (log K) higher than 4. To remove these contaminants from biosolids, a wide range of technologies have been developed. Our multicriteria analysis shows that anaerobic digestion is the most mature and practical. Thermal treatment is a viable option; however, it still requires additional improvements in infrastructure, legislation, and public acceptance.
Topics: Microplastics; Plastics; Biosolids; Dioxins; Flame Retardants
PubMed: 38266587
DOI: 10.1016/j.jhazmat.2024.133471 -
Chemosphere Mar 2024Torrefaction constitutes one of the promising technologies for the management of waste biomass and the production of high-carbon products for combustion, gasification,...
Torrefaction constitutes one of the promising technologies for the management of waste biomass and the production of high-carbon products for combustion, gasification, adsorption of pollutants or soil treatment. Unfortunately, waste biomass may be contaminated with toxic persistent organic pollutants, such as polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/PCDF) and dioxin-like biphenyls (dl-PCB). Literature does not provide consistent measurements on how the low-temperature thermochemical processing, such as torrefaction, affects the toxicity of biomass. This contribution assesses how a torrefaction treatment, conducted at 200 °C, modifies the toxicity due to PCDD/PCDF/dl-PCB in biomass. We deploy the XDS-CALUX biotest on five types of waste biomass (sewage sludge, tree bark, cattle manure, spent coffee ground, common reed), before and after treatment. The content of total dioxin- & biphenyl fraction compounds in the raw biomass, investigated in this study, varies from 0.14 to 3.67 pg BEQ·g, and in the torrefied biomass between 0.17 and 6.00 pg BEQ·g; BEQ stands for bioanalytical equivalent. This increase is statistically insignificant at p = 0.05, taking into account all types of examined biomass. This proves that low-temperature torrefaction cannot detoxify biomass, i.e., chars, produced from biomass characterized by elevated concentration of PCDD/PCDF/dl-PCB, will reflect the contamination of the feedstocks. With respect to heavy metals, we conclude that only the content of Cd in biomass, and, to a lesser extent, the abundance of Cu and Fe, modify the toxicity of this material during its thermochemical treatment at low temperature.
Topics: Animals; Cattle; Dioxins; Biomass; Polychlorinated Biphenyls; Benzofurans; Polychlorinated Dibenzodioxins; Sewage; Biological Assay; Dibenzofurans, Polychlorinated
PubMed: 38253086
DOI: 10.1016/j.chemosphere.2024.141258 -
Toxics Jan 2024Polychlorinated biphenyls (PCBs) are organic chemicals consisting of a biphenyl structure substituted with one to ten chlorine atoms, with 209 congeners depending on the...
Theoretical Studies on the Quantitative Structure-Toxicity Relationship of Polychlorinated Biphenyl Congeners Reveal High Affinity Binding to Multiple Human Nuclear Receptors.
Polychlorinated biphenyls (PCBs) are organic chemicals consisting of a biphenyl structure substituted with one to ten chlorine atoms, with 209 congeners depending on the number and position of the chlorine atoms. PCBs are widely known to be endocrine-disrupting chemicals (EDCs) and have been found to be involved in several diseases/disorders. This study takes various molecular descriptors of these PCBs (e.g., molecular weight) and toxicity endpoints as molecular activities, investigating the possibility of correlations via the quantitative structure-toxicity relationship (QSTR). This study then focuses on molecular docking and dynamics to investigate the docking behavior of the strongest-binding PCBs to nuclear receptors and compares these to the docking behavior of their natural ligands. Nuclear receptors are a family of transcription factors activated by steroid hormones, and they have been investigated to consider the impact of PCBs on humans in this context. It has been observed that the docking affinity of PCBs is comparable to that of the natural ligands, but they are inferior in terms of stability and interacting forces, as shown by the RMSD and total energy values. However, it is noted that most nuclear receptors respond to PCBs similarly to how they respond to their natural ligands-as shown in the RMSF plots-the most similar of which are seen in the ER, THR-β, and RAR-α. However, this study is performed purely in silico and will need experimental verification for validation.
PubMed: 38251005
DOI: 10.3390/toxics12010049 -
Toxics Dec 2023Suspended particulate matter (SPM), polychlorinated biphenyls (PCBs), and organochlorine pesticides (OCP) were studied in the snow cover at urban and suburban localities...
Persistent Organic Pollutants and Suspended Particulate Matter in Snow of Eastern Siberia in 2009-2023: Temporal Trends and Effects of Meteorological Factors and Recultivation Activities at Former Industrial Area.
Suspended particulate matter (SPM), polychlorinated biphenyls (PCBs), and organochlorine pesticides (OCP) were studied in the snow cover at urban and suburban localities in the Irkutsk region, Eastern Siberia for their temporal variations in 2009-2023, daily deposition fluxes (DDFs), and effects of some meteorological factors, as well as the effects of different technogenic activities in the industrial area of the former organochlorine enterprises of Usol'ekhimprom. SPM loads at both stations were found to be at a low level of pollution. The levels of HCB, α + γ-HCH, and ∑,'-DDX were lower than Russian maximum permissible levels (MPLs) in drinking water, groundwater, and surface water for household drinking and cultural purposes. The sums of all organochlorine compounds studied in snow were higher than the MPL in freshwater water bodies for fishery purposes. The levels of the DDFs of HCHs, DDTs, and heptachlorinated PCB decreased, di- and trichlorinated PCB levels increased, and HCB levels changed at a polynomial line during 2009-2023. The change in the relative composition of PCBs was found as a result of recultivation activities at the industrial area of the former organochlorine enterprise of Usol'ekhimprom. The air humidity and temperature are the key meteorological factors affecting the DDFs of PCBs and OCPs.
PubMed: 38250967
DOI: 10.3390/toxics12010011 -
Environment International Jan 2024Polychlorinated alkanes (PCAs) constitute a large group of individual congeners originating from commercial chlorinated paraffin (CP) products with carbon chain lengths...
BACKGROUND
Polychlorinated alkanes (PCAs) constitute a large group of individual congeners originating from commercial chlorinated paraffin (CP) products with carbon chain lengths of PCAs-C, PCAs-C, and PCAs-C, occasionally containing PCAs-C impurities. The extensive use of CPs has led to global environmental pollution of PCAs. This study aimed to quantify PCAs in paired serum and breast milk of lactating Swedish mothers, exploring their concentration relationship.
METHODS
Twenty-five paired samples of mothers' blood serum and breast milk were analysed and concentrations were determined for PCAs C and compared to 4,4'-DDE, the PCB congener 2,2',4,4',5,5'-hexachlorobiphenyl (CB-153), and hexachlorobenzene (HCB).
RESULTS
The median concentrations of PCAs-C, PCAs-C, PCAs-C, PCAs-C and ΣPCAs in serum were 14, 790, 520, 16 and 1350 ng/g lipid weight (lw), respectively, and in breast milk 0.84, 36, 63, 6.0 and 107 ng/g lw. Levels of 4,4'-DDE, CB-153 and HCB were comparable in the two matrices, serum and breast milk at 17, 12 and 4.9 ng/g lw. The results show significant differences of PCAs-C and PCAs-C in breast milk with 22- and 6.2-times lower lw-based concentrations than those measured in serum. On wet weight the differences serum/breast milk ratios of PCAs-C, PCAs-C, PCAs-C, PCAs-C and ΣPCAs were 1.7, 3.2, 1.0, 0.4 and 1.6, respectively, while the ratio for 4,4'-DDE, CB-153 and HCB were each close to 0.1.
CONCLUSION
Swedish lactating mothers had high serum concentrations of PCAs-C and PCAs-C, with the ΣPCAs median serum concentration of 1350 ng/g lw. The breast milk concentration, although considerably lower at 107 ng/g lw, still surpassed those of 4,4'-DDE, CB-153 and HCB, suggesting an exposure risk of infants to PCAs. The variation in blood and breast milk accumulation between PCAs and studied legacy POPs, is rarely discussed but warrants further studies on partitioning properties as well as associated toxicological implications.
Topics: Female; Infant; Humans; Milk, Human; Environmental Pollutants; Lactation; Hexachlorobenzene; Serum; Sweden; Cohort Studies; Polychlorinated Biphenyls; Hydrocarbons, Chlorinated
PubMed: 38232504
DOI: 10.1016/j.envint.2024.108440 -
Neurotoxicology Mar 2024Occupational exposure to polychlorinated biphenyls (PCBs) continues to affect the health of exposed individuals until today. This study aims to expand previous findings...
Occupational exposure to polychlorinated biphenyls (PCBs) continues to affect the health of exposed individuals until today. This study aims to expand previous findings by examining the development of neuropsychological functions of occupationally exposed participants over time. Especially verbal fluency and sensorimotor processing, found to be impaired in a previous study, were thus of particular interest. A total of 116 participants, who were part of the HELPcB cohort, underwent a neuropsychological test battery covering a multitude of cognitive functions. Plasma PCB levels were determined for each participant and classified as elevated or normal based on comparative values drawn from the German general population. Two structural equation models were then used to examine the effects of elevated PCB levels on neuropsychological functions. Results suggest that participants who displayed increased PCB plasma levels continued to show impairments in verbal fluency but not in sensorimotor processing after a second examination one year after the first measurement. Specifically, low chlorinated PCBs are associated with impaired verbal fluency, as compared to high-chlorinated and dioxin-like congeners. Alteration of dopamine concentration in response to PCB exposure might be a potential explanation of this result.
Topics: Humans; Polychlorinated Biphenyls; Occupational Exposure; Polychlorinated Dibenzodioxins; Dopamine; Dioxins
PubMed: 38215798
DOI: 10.1016/j.neuro.2024.01.001 -
Journal of Hazardous Materials Mar 2024The environmental fate of hazardous hydrophobic pollutants in the marine environment is strongly influenced by organic carbon (OC) cycling. As an example, the...
The environmental fate of hazardous hydrophobic pollutants in the marine environment is strongly influenced by organic carbon (OC) cycling. As an example, the seasonality in primary production impacts both water column OC quantity and quality, which may influence pollutant mass transport from the water column to the sediment. This study aims to better understand the role of water column OC variability for the fate of pollutants in a near-coastal area. We conducted an in situ sampling campaign in the coastal Baltic Proper during two seasons, summer and autumn. We used polycyclic aromatic hydrocarbons (PAHs) and polychlorinated biphenyls (PCBs) as model compounds, as they represent a wide range in physicochemical properties and are ubiquitous in the environment. Freely dissolved, and OC-bound concentrations were studied in the water column and surface sediment. We found stronger sorption of pollutants to suspended particulate matter (SPM) during the summer compared to the autumn (average 0.6 and 0.9 log unit higher particle-water partition coefficients during summer for PAHs and PCBs). Our data suggest that stronger sorption mirrors a compositional change of the OC towards higher contribution of labile OC during the summer, characterized by two times higher fatty acid and 24% higher dicarboxylic acids in SPM during summer. High concentrations of OC in the water column during the autumn resulted in increased SPM-mediated sinking fluxes of pollutants. Our results suggest that future changes in primary production are prone to influence the bioavailability and mobility of pollutants in costal zones, potentially affecting the residence time of these hazardous substances in the circulating marine environment.
PubMed: 38211519
DOI: 10.1016/j.jhazmat.2023.133393