Reviewing the current state of legacy POP-brominated flame retardants in plastic childcare products and toys: a scoping review protocol.

BACKGROUND: Due to their adverse environmental and health impacts, brominated flame retardants (BFRs) are listed in Annex A of the Stockholm Convention for global elimination of production and use. Their health impacts include endocrine disruption, cancer, reproductive effects, and neurobehavioral and developmental disorders in children. Emerging literature suggests that legacy POP-BFRs are increasingly found in consumer products, including those used for and by children. The presence of legacy POP-BFRs in children's products is a big concern. Children are more vulnerable to chemical exposure risks than adults because their bodies are still developing and fragile. The rising problem is contributed to by the global push towards a circular economy that encourages responsible production and consumption by practising the recycling of waste materials. Waste materials such as electronic and electrical equipment plastics often contain POP-BFRs. POP-BFRs in waste materials are transferred into new products through recycling. The recycled products have become a potential source of exposure to legacy POP-BFRs for vulnerable populations, particularly children. Our scoping review aims to map and summarise the emerging literature. This information is needed to inform evidence-based policies to protect children from toxic exposures. METHODS: Our scoping review will follow a methodological framework proposed by Arksey and O'Malley. Peer-reviewed and grey literature on the topic will be retrieved from electronic databases and other relevant sites. Two reviewers will screen titles and abstracts, followed by a full-text review of studies for eligibility based on the established inclusion and exclusion criteria. Data will be extracted, and findings will be mapped in a table according to study settings, types of children's products tested, and concentration of legacy POP-BFRs in contaminated products. A map chart will be created to display how contaminated products are spread globally. DISCUSSION: Because of their unique vulnerabilities, children continue to suffer disproportionate exposures to toxic chemicals compared to adults. Information on potential exposures, particularly for children, is crucial to make evidence-based policies. We intend to map and summarise the emerging literature on legacy POP-BFRs in children's products. Findings will be disseminated to relevant stakeholders through publishing in a peer-reviewed scientific journal and policy briefs. SYSTEMATIC REVIEW REGISTRATION: The protocol is registered with the Open Science Framework ( https://doi.org/10.17605/OSF.IO/7KDE5 ).

Microplastics and Nanoplastics in Atheromas and Cardiovascular Events.

BACKGROUND: Microplastics and nanoplastics (MNPs) are emerging as a potential risk factor for cardiovascular disease in preclinical studies. Direct evidence that this risk extends to humans is lacking. METHODS: We conducted a prospective, multicenter, observational study involving patients who were undergoing carotid endarterectomy for asymptomatic carotid artery disease. The excised carotid plaque specimens were analyzed for the presence of MNPs with the use of pyrolysis-gas chromatography-mass spectrometry, stable isotope analysis, and electron microscopy. Inflammatory biomarkers were assessed with enzyme-linked immunosorbent assay and immunohistochemical assay. The primary end point was a composite of myocardial infarction, stroke, or death from any cause among patients who had evidence of MNPs in plaque as compared with patients with plaque that showed no evidence of MNPs. RESULTS: A total of 304 patients were enrolled in the study, and 257 completed a mean (±SD) follow-up of 33.7±6.9 months. Polyethylene was detected in carotid artery plaque of 150 patients (58.4%), with a mean level of 21.7±24.5 µg per milligram of plaque; 31 patients (12.1%) also had measurable amounts of polyvinyl chloride, with a mean level of 5.2±2.4 µg per milligram of plaque. Electron microscopy revealed visible, jagged-edged foreign particles among plaque macrophages and scattered in the external debris. Radiographic examination showed that some of these particles included chlorine. Patients in whom MNPs were detected within the atheroma were at higher risk for a primary end-point event than those in whom these substances were not detected (hazard ratio, 4.53; 95% confidence interval, 2.00 to 10.27; P<0.001). CONCLUSIONS: In this study, patients with carotid artery plaque in which MNPs were detected had a higher risk of a composite of myocardial infarction, stroke, or death from any cause at 34 months of follow-up than those in whom MNPs were not detected. (Funded by Programmi di Ricerca Scientifica di Rilevante Interesse Nazionale and others; ClinicalTrials.gov number, NCT05900947.).

[Research Progress on Characteristics of Human Microplastic Pollution and Health Risks].

Microplastic pollution is not only an environmental problem but also a social problem. Many studies have been conducted on the sources, abundance, and distribution of microplastics in the environment, but an understanding of human exposure levels and potential health risks remains very limited. Based on the bibliometric methods, the present review systematically summarized the exposure pathways of microplastics in humans, and then the characteristics and potential adverse impacts on human health were expounded upon. Available literature showed that microplastics in human bodies were mainly concentrated on sizes smaller than 50 µm, and polyethylene (PE), polypropylene (PP), and polyethylene terephthalate (PET) were the main polymers. Microplastics in environments entered human bodies mainly through food and respiratory pathways, then accumulated in lung and gastrointestinal tissues. Most importantly, small-sized microplastics could distribute in tissues and organs via the circulatory system. The results from lab-based toxicological experiments showed that microplastics not only posed threats to cell membrane integrity, immune stress, gut microbiota, and energy metabolism but also had potentially adverse impacts on the reproductive system. To further understand the health risks of microplastic pollution, it is necessary to promote research on the toxicological effects of microplastics as well as the inner mechanisms and also to establish risk assessment frameworks for evaluating microplastic pollution. These works are crucial to preventing the risks of microplastic pollution with scientific evidence.

Pollution characteristics and potential health effects of airborne microplastics and culturable microorganisms during urban haze in Harbin, China.

In this study, active sampling technology was used to collect microplastics (MPs) and microorganisms simultaneously on haze days in Harbin, China. Airborne MPs concentrations in Junior high school (162.4 ± 44.6 particles/m3) with high vehicular and pedestrian traffic was higher than those in University (63.2 ± 21.8 particles/m3) and Park (12.8 ± 5.5 particles/m3). More airborne MPs were detected in the night samples than in the morning and noon samples. The majority (69.06 %) of airborne MPs measured less than 100 µm, with fibers (69.4 %) being the predominant form. Polyesters and polyethylene were the dominant polymers. In addition, airborne MPs concentrations were positively correlated with microorganisms and PM10 concentrations, and the health hazards associated with microorganisms and MPs exposure via inhalation far exceeded those associated with skin contact, which can serve as a theoretical foundation for considering MPs as indicators of air quality in the future.

Fish microplastic ingestion may induce tipping points of aquatic ecosystems.

Microplastics can be ingested by a wide range of aquatic animals. Extensive studies have demonstrated that microplastic ingestion-albeit often not lethal-can affect a range of species life-history traits. However, it remains unclear how the sublethal effects of microplastics on individual levels scale up to influence ecosystem-level dynamics through cascading trophic interactions. Here we employ a well-studied, empirically fed three-species trophic chain model, which was parameterized to mimic a common type of aquatic ecosystems to examine how microplastic ingestion by fish on an intermediate trophic level can produce cascading effects on the species at both upper and lower trophic levels. We show that gradually increasing microplastics in the ingested substances of planktivorous fish may cause population structure effects such as skewed size distributions (i.e. reduced average body length vs. increased maximal body size), and induce abrupt declines in fish biomass and reproduction. Our model analysis demonstrates that these abrupt changes correspond to an ecosystem-level tipping point, crossing which difficult-to-reverse ecosystem degradation can happen. Importantly, microplastic pollution may interact with other anthropogenic stressors to reduce safe operating space of aquatic ecosystems. Our work contributes to better understanding complex effects of microplastic pollution and anticipating tipping points of aquatic ecosystems in a changing world. It also calls attention to an emerging threat that novel microplastic contaminants may lead to unexpected and abrupt degradation of aquatic ecosystems, and invites systematic studies on the ecosystem-level consequences of microplastic exposure.

Adverse Effects of Micro- and Nanoplastics on Humans and the Environment.

The pervasive pollution caused by nano- and microplastics (N/MPLs) is a pressing concern, and was exacerbated during the COVID-19 pandemic due to the substantial release of disposable Personal Protective Equipment (PPE) into the environment [...].

Micro-algal astaxanthin ameliorates polystyrene microplastics-triggered necroptosis and inflammation by mediating mitochondrial Ca2+ homeostasis in carp's head kidney lymphocytes (Cyprinus carpio L.).

Polystyrene microplastics (PM) is a pressing global environmental concern, posing substantial risks to aquatic ecosystems. Microalgal astaxanthin (MA), a heme pigment, safeguards cells against oxidative damage induced by free radicals, which contributes to various health conditions, including aging, inflammation and chronic diseases. Herein, we investigated the potential of MA in ameliorating the immunotoxicity of PM on carp (Cyprinus carpio L.) based on head kidney lymphocytes treated with PM (250 µM) and/or MA (100 µM). Firstly, CCK8 results showed that PM resulted in excessive death of head kidney lymphocytes. Secondly, head kidney lymphocytes treated with PM had a higher proportion of necroptosis, and the levels of necroptosis-related genes in head kidney lymphocytes were increased. Thirdly, the relative red fluorescence intensity of JC-1 and MitoSox showed decreased mitochondrial membrane potential and increased mtROS in head kidney lymphocytes treated with PM. MitoTracker® Green FM fluorescence analysis revealed enhanced mitochondrial Ca2+ levels in PM-treated lymphocytes, corroborating the association between PM exposure and elevated intracellular Ca2+ dynamics. PM exposure resulted in upregulation of calcium homeostasis-related gene (Orail, CAMKIIδ and SLC8A1) in lymphocytes. Subsequent investigations revealed that PM exposure reduced miR-25-5p expression while increasing levels of MCU, MICU1, and MCUR1. Notably, these effects were counteracted by treatment with MA. Furthermore, PM led to the elevated secretion of inflammatory factors (IFN-γ, IL-1ß, IL-2 and TNF-α), thereby inducing immune dysfunction in head kidney lymphocytes. Encouragingly, MA treatment effectively mitigated the immunotoxic effects induced by PM, demonstrating its potential in ameliorating necroptosis, mitochondrial dysfunction and immune impairment via regulating the miR-25-5p/MCU axis in lymphocytes. This study sheds light on safeguarding farmed fish against agrobiological threats posed by PM, highlighting the valuable applications of MA in aquaculture.

Microplastics: Human exposure assessment through air, water, and food.

BACKGROUND: Microplastics (MP) are plastic particles with dimension up to 5 mm. Due to their persistence, global spread across different ecosystems and potential human health effects, they have gained increasing attention during the last decade. However, the extent of human exposure to MP through different pathways and their intake have not been elucidated. OBJECTIVES: The objective of this review is to provide an overview on the pathways of exposure to MP through inhalation, ingestion, and dermal contact considering data from the open bibliography on MP in air, dust, food, water and drinks. METHODS: A bibliographic search on Scopus and PubMed was conducted using keywords on MP in outdoor and indoor air, indoor dust, food including beverages and water and human intake (n = 521). Articles were sorted by their title and abstract (n = 213), and only studies reporting MP identification and quantification techniques were further considered (n = 168). A total of 115 articles that include quality assurance and quality control (QA/QC) procedures are finally discussed in the present review. Based on MP concentration data available in literature, we estimated the potential inhaled dose (ID), dust intake (DI), the estimated daily intake (EDI) via food and beverages. Finally, the total daily intake (TDI) considering both inhalation and ingestion routes are provided for adults, infants and newborns. RESULTS: The concentrations of MP in outdoor and indoor air, dust, and in food and water are provided according to the bibliography. Human exposure to MP through dust ingestion, inhalation of air and food/drinks consumption revealed that indoor air and drinking waters were the main sources of MP. CONCLUSIONS: This study reveals that humans are constantly exposed to MP, and that the indoor environment and the food and water we ingest decisively contribute to MP intake. Additionally, we highlight that infants and newborns are exposed to high MP concentrations and further studies are needed to evaluate the presence and risk of MP in this vulnerable age-population.

Migration of oligomers from Tritan™ copolyester: application of hydrolysis for overall oligomer determination.

Tritan™ (a kind of glycol-modified polycyclohexylene dimethylene terephthalate) is a novel copolyester mainly in use for the production of sports bottles and food storage containers. Oligomers in three food-grade Tritan™ samples were identified after dissolution-precipitation by high performance liquid chromatography with diode array detection and mass spectrometry and quantified after alkaline hydrolysis to the monomers. The obtained overall oligomer content <1000 Da determined by hydrolysis ranged from 7.2 to 10.6 mg/g material. Three consecutive migration experiments were performed according to the Commission Regulation (EU) No 10/2011. Oligomer migration values decreased from first to third migration during all simulations. Less than 25 µg/kg (third migrate) were detected in bottle migrates when tested under room temperature storage conditions (40 °C, 24 h) with simulants 3% acetic acid, 20 and 50% ethanol and during hot-fill testing (70 °C, 2 h) with simulants 3% acetic acid and 20% ethanol, respectively, while 170 µg/kg were determined in 50% ethanol after migration at 70 °C for 2 h. Food storage containers that were labelled as microwave-suitable by the supplier were tested according to the Joint Research Centre recommendations for microwave dishware. A strong deformation of the containers as well as a loss of transparency were observed during the tests (100 °C, 2 h with 10% ethanol and 3% acetic acid in an autoclave, 121 °C, 30 min with sunflower oil), questioning the suitability of the material for microwave applications. Maximum oligomer migration was 379 µg/kg during the third migration (sunflower oil at 121 °C for 30 min). Based on the migration data and an in silico oligomer evaluation according to the threshold of toxicological concern concept, no exceedances of daily thresholds for oligomers are expected from a proper use of Tritan™ drinking bottles, even with hot drinks.

Plastic pollution on the world's coral reefs.

Coral reefs are losing the capacity to sustain their biological functions1. In addition to other well-known stressors, such as climatic change and overfishing1, plastic pollution is an emerging threat to coral reefs, spreading throughout reef food webs2, and increasing disease transmission and structural damage to reef organisms3. Although recognized as a global concern4, the distribution and quantity of plastics trapped in the world's coral reefs remains uncertain3. Here we survey 84 shallow and deep coral ecosystems at 25 locations across the Pacific, Atlantic and Indian ocean basins for anthropogenic macrodebris (pollution by human-generated objects larger than 5 centimetres, including plastics), performing 1,231 transects. Our results show anthropogenic debris in 77 out of the 84 reefs surveyed, including in some of Earth's most remote and near-pristine reefs, such as in uninhabited central Pacific atolls. Macroplastics represent 88% of the anthropogenic debris, and, like other debris types, peak in deeper reefs (mesophotic zones at 30-150 metres depth), with fishing activities as the main source of plastics in most areas. These findings contrast with the global pattern observed in other nearshore marine ecosystems, where macroplastic densities decrease with depth and are dominated by consumer items5. As the world moves towards a global treaty to tackle plastic pollution6, understanding its distribution and drivers provides key information to help to design the strategies needed to address this ubiquitous threat.

Review of microplastics in the indoor environment: Distribution, human exposure and potential health impacts.

The emergence of microplastics (MPs) pollution as a global environmental concern has attracted significant attention in the last decade. The majority of the human population spends most of their time indoors, leading to increased exposure to MPs contamination through various sources such as settled dust, air, drinking water and food. Although research on indoor MPs has intensified significantly in recent years, comprehensive reviews on this topic remain limited. Therefore, this review comprehensively analyses the occurrence, distribution, human exposure, potential health impact and mitigation strategies of MPs in the indoor air environment. Specifically, we focus on the risks associated with finer MPs that can translocate into the circulatory system and other organs, emphasizing the need for continued research to develop effective strategies to mitigate the risks associated with MPs exposure. Our findings suggest that indoor MPs impose potential risk to human health, and strategies for mitigating exposure should be further explored.