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Started by Recusant, December 22, 2021, 07:45:23 PM
QuotePlastic waste, amounting to 8 million tons annually, turns into microplastics(MPs) through constant exposure to UV rays and sea waves. These MPs are consumed by lower-level organisms such as plankton, posing a threat to humans at the top of the food chain.The research team conducted an experiment in which MPs of 2㎛ or less in size were administered orally to mice for 7 days in order to elucidate the hazards of MPs. The team discovered that nano-plastics with the size of 2㎛ or less even passed through the 'blood-brain barrier' that prevents the brain uptake of hazardous substances. It was highly unusual to observe solids such as MPs, passed through the brain-blood-brain barrier.Additionally, the team also revealed that MPs accumulate in microglial cells in the brain by applying immunohistochemistry. Through the experiments conducted on the MPs of different sizes(0.2㎛, 2㎛, 10㎛), the team was able to confirm that MPs of less than 2㎛ accumulated in the cytoplasm of microglial cells and significantly decreased the cell proliferation ability after several tens of hours. The team explained that microglial cells recognize MPs as an external threat, leading to microglial phagocytosis, which causes apoptosis following changes in cellular morphology.[Continues . . .]
QuoteAbstract:The remarkable increase in plastic usage and widespread microplastic (MP) pollution has emerged as a substantial concern today. Many recent studies have revealed MPs as potentially hazardous substances in mammals. Despite several reports on the impact of small MPs in the brain and behaviors in aquatic animals, it is still unclear how small MPs affect the brain and its underlying cellular physiology in terrestrial animals. In this study, we investigated the accumulation of polystyrene MPs (PS-MPs) in mouse brain after oral treatment using three types of fluorescent PS-MPs of different sizes (0.2,2 and 10 μm). We found that PS-MPs were deposited in microglial cells of the brain. Following differential treatment of PS-MPs in human microglial HMC-3 cells, we identified changes in cellular morphology, immune responses, and microglial apoptosis induced by phagocytosis of 0.2 and 2 μm PS-MPs. By analyzing the PS-MP-treated HMC-3 cell transcriptome, we showed that PS-MPs treatment altered the expression of clusters of immune response genes, immunoglobulins, and several related microRNAs. In addition, we confirmed alterations in microglial differentiation marker expression with the activation of NF-κB, pro-inflammatory cytokines and apoptotic markers in PS-MP-treated human microglial cells and in mouse brain. Our findings suggest a potential risk of small PS-MPs in microglial immune activation, which leads to microglial apoptosis in murine and human brains.[¶ added. - R]
Quote from: Davin on January 05, 2022, 10:42:59 PMWe really have to cut down on plastics use, as well as figuring out how to eliminate a majority of what we've already put out there,
Quote from: Bad Penny II on January 07, 2022, 12:55:58 PMQuote from: Davin on January 05, 2022, 10:42:59 PMWe really have to cut down on plastics use, as well as figuring out how to eliminate a majority of what we've already put out there,Today I saw flour packaged in a plastic bottle
QuoteMicroplastic pollution has been detected in human blood for the first time, with scientists finding the tiny particles in almost 80% of the people tested.The discovery shows the particles can travel around the body and may lodge in organs. The impact on health is as yet unknown. But researchers are concerned as microplastics cause damage to human cells in the laboratory and air pollution particles are already known to enter the body and cause millions of early deaths a year.[. . .]The scientists analysed blood samples from 22 anonymous donors, all healthy adults and found plastic particles in 17. Half the samples contained PET plastic, which is commonly used in drinks bottles, while a third contained polystyrene, used for packaging food and other products. A quarter of the blood samples contained polyethylene, from which plastic carrier bags are made."Our study is the first indication that we have polymer particles in our blood – it's a breakthrough result," said Prof Dick Vethaak, an ecotoxicologist at Vrije Universiteit Amsterdam in the Netherlands. "But we have to extend the research and increase the sample sizes, the number of polymers assessed, etc." Further studies by a number of groups are already under way, he said.[Continues . . .]
QuoteAbstract:Plastic particles are ubiquitous pollutants in the living environment and food chain but no study to date has reported on the internal exposure of plastic particles in human blood. This study's goal was to develop a robust and sensitive sampling and analytical method with pyrolysis double shot - gas chromatography/mass spectrometry and apply it to measure plastic particles ≥700 nm in human whole blood from 22 healthy volunteers. Four high production volume polymers applied in plastic were identified and quantified for the first time in blood. Polyethylene terephthalate, polyethylene and polymers of styrene (a sum parameter of polystyrene, expanded polystyrene, acetonitrile butadiene styrene etc.) were the most widely encountered, followed by poly(methyl methylacrylate). Polypropylene was analysed but values were under the limits of quantification. In this study of a small set of donors, the mean of the sum quantifiable concentration of plastic particles in blood was 1.6 µg/ml, showing a first measurement of the mass concentration of the polymeric component of plastic in human blood. This pioneering human biomonitoring study demonstrated that plastic particles are bioavailable for uptake into the human bloodstream. An understanding of the exposure of these substances in humans and the associated hazard of such exposure is needed to determine whether or not plastic particle exposure is a public health risk.
QuoteBiologists in Rio de Janeiro studying the presence of microplastics in marine life off the coast of Brazil's postcard city have found that the impact of plastic pollution is far worse than they had feared.The team of biologists don wetsuits and oxygen canisters to dive into the tropical waters around Rio and sample marine life from the ocean. They then measure the quantity of microplastics found inside the organisms in a laboratory.Plastic objects which end up in the ocean break down into smaller pieces and can eventually end up inside fish and other creatures, researchers told Reuters."I was frightened. I knew I would find some [microplastics] but I never thought it would be that much," said Raquel Neves, a marine biologist at the Federal University of the State of Rio de Janeiro (UNIRIO), who finds the microplastics under a microscope.[Continues . . .]
QuoteOn January 26, the Instituto Mar Urbano launched a video called "PlastiTox: A Multi-Integrated Approach to Assessing the Toxicity of Plastic Pollutants to Biota and Coastal Ecosystem Services," as a result of a partnership with UNIRIO and OceanPact to present an unparalleled scientific study about levels of microplastics found in the ocean and in sea creatures off the coast of Rio de Janeiro.The PlastiTox video was launched in a live online event on the Instituto Mar Urbano's YouTube channel, featuring UNIRIO researchers; the institute's director, Ricardo Gomes; and OceanPact's sustainability director, Fernando Borensztein. After that, the video was posted on all three institutions' social media.Over the course of three days, the expedition documented in PlastiTox collected samples in Guanabara Bay and around the Tijucas Islands, off the coast of the neighborhood of Barra da Tijuca. The entire project was supported by OceanPact, which provided a manned vessel to help with the research and production of the mini-documentary.[Continues . . .]
QuoteA new study by Tel Aviv University researchers found that in a marine environment, microplastics absorb and concentrate toxic organic substances and thus increase their toxicity by a factor of 10, which may lead to a severe impact on human health. The study was conducted by Dr. Ines Zucker of the School of Mechanical Engineering and the Porter School of the Environment and Earth Sciences at Tel Aviv University, together with Ph.D. student Andrey Eitan Rubin.The study was recently published in the journal Chemosphere.[Continues . . .]
QuoteAbstract:High levels of persistent contaminants such as microplastics (MPs) and trace organic compounds (TrOCs) in the aquatic environment have become a major threat on the ecosystem and human health. While MP's role as a vector of environmental TrOCs is widely discussed in the literature, the corresponding implications of the interaction between these two compounds on human health (i.e., their joint toxic effect) have not been illustrated. Using a TrOCs model (Triclosan, TCS) and primary MPs (polystyrene microbeads), this work evaluates the sorption and desorption potential of TCS and MPs in simulated environmental and cellular conditions, respectively, and estimates the single and joint toxicity of these interactions toward human cells (Caco-2). Surface functionality of the microbeads highly increased their adsorption capacity of TCS, from 2.3 mg TCS for non−functionalized microbeads to 4.6 mg and 6.1 mg TCS per gram of microbeads for amino- and carboxyl-functionalized MPs, respectively. Using non-functionalized MPs, non-specific "hydrophobic-like" interactions and π-π interactions dominated the sorption mechanism of TCS; however, the addition of hydrogen interactions between functionalized microbeads and TCS increased the microbeads' overall sorption capacity. TCS was desorbed from both functionalized and non-functionalized MPs when changing from environmental conditions to cellular conditions. Desorption was found to be dependent on the matrix complexity and protein content as well as microbead functionality. Finally, toxicity tests suggested that while low concentrations of TCS and MPs (separately) have minor toxic effect toward Caco-2 cells, TCS-sorbed MPs at similar concentrations have an order of magnitude higher toxicity than pristine MPs, potentially associated with the close interaction of both MP and TCS with the cells. Overall, this study not only elucidates the role of MPs as a TrOC vector, but also demonstrates a realistic scenario in which co-presence of these environmental contaminants poses risks to the environment and human health.
QuoteThere is global concern about PFAS because they have been used widely, are persistent in the environment and accumulate in our bodies over time.There was no way to reduce the amount of PFAS found in the body – until now.Our new randomised clinical trial, published in the journal JAMA Network Open, has found regularly donating blood or plasma can reduce blood PFAS levels.[Continues . . .]
QuoteAbstract--Results: A total of 285 firefighters (279 men [97.9%]; mean [SD] age, 53.0 [8.4] years) were enrolled; 95 were randomly assigned to donate plasma, 95 were randomly assigned to donate blood, and 95 were randomly assigned to be observed. The mean level of PFOS [perfluorooctane sulfonate] at 12 months was significantly reduced by plasma donation (–2.9 ng/mL; 95% CI, –3.6 to –2.3 ng/mL; P < .001) and blood donation (–1.1 ng/mL; 95% CI, –1.5 to –0.7 ng/mL; P < .001) but was unchanged in the observation group. The mean level of PFHxS [perfluorohexane sulfonic acid] was significantly reduced by plasma donation (–1.1 ng/mL; 95% CI, –1.6 to –0.7 ng/mL; P < .001), but no significant change was observed in the blood donation or observation groups. Analysis between groups indicated that plasma donation had a larger treatment effect than blood donation, but both were significantly more efficacious than observation in reducing PFAS levels.