New evidence of the presence of micro- and nanoplastic particles in bronchioalveolar lavage samples of clinical trial subjects

In vitro effects of aged low-density polyethylene micro(nano)plastic particles on human airway epithelial cells

Airborne micro(nano)plastic (MNP) pollution has emerged as a major global concern due to its increasingly worrying adverse health effects. Environmental weathering and UV irradiation of plastic waste, together with tire wear, generate airborne MNPs with irregular shapes and varied sizes, with low-density polyethylene (LDPE) being the predominant plastic type. However, knowledge of MNPs' toxicological effects remains scarce, as current in vitro research mainly focuses on commercial polystyrene beads. In this study, we investigated for the first time the toxicological effects of environmentally relevant aged LDPE MNPs on human bronchial epithelial cells (BEAS-2B). UV-aged LDPE fragments of irregular sizes and shapes were used to mimic real atmospheric particles, and BEAS-2B cells were exposed to 10-1000 μg/cm2 of LDPE MNPs. Our results showed that MNPs were internalized by BEAS-2B cells and promoted epithelial-to-mesenchymal transition (EMT), characterized by reduced β-catenin and increased vimentin expression, enhanced motility, and disturbed cell cycle. Moreover, exposure to aged LDPE MNPs significantly increased intracellular ROS levels and reduced cell proliferation rate at the highest dose. LDPE MNPs triggered oxidative stress in BEAS-2B cells through activation of the NRF2 signaling pathway, with impaired autophagic flux indicated by increased expression of p62 and LC3A/B. Importantly, LDPE MNP exposure significantly increased the secretion of pro-inflammatory mediators (CD62E, CD62P, ICAM-1, IL-6, IL-8), accompanied by suppressive effects on mitochondrial respiration and glycolytic function at 1000 μg/cm2. Taken together, our findings suggest that inhalation of LDPE MNPs could impact the morphology and function of the human airway epithelium and respiratory health in general.

Unseen toxins: Exploring the human health consequences of micro and nanoplastics

Micro and nanoplastics (MNPs) contamination constitute a pressing global issue with considerable ramifications for human health. Particles originating from the decomposition of plastic waste permeate ecosystems and disturb biological systems, especially the gastrointestinal (GI) tract. MNPs compromise the intestinal barrier, provoke oxidative stress, inflammation, and immunological dysfunction, and modify gut microbiota, which is associated with metabolic problems, inflammatory bowel disease (IBD), and colorectal cancer. MNPs traverse biological barriers beyond the gastrointestinal system, including the blood-brain barrier, colonic mucus layer, and placental barrier, resulting in accumulation in essential organs such as the liver, kidneys, and brain. This results in inflammatory damage, metabolic abnormalities, and oxidative stress, specifically affecting liver disease due to microbiota metabolite alteration and nephrotoxicity in the kidneys. Airborne MNPs pose an additional risk to respiratory health, aggravating ailments such as asthma, chronic obstructive pulmonary disease (COPD), and pulmonary fibrosis. At-risk groups, such as pregnant women, newborns, and the elderly, encounter increased dangers, as MNPs traverse the placental barrier and may induce neurological and intergenerational health consequences. These particles function as vectors for environmental pollutants, exacerbating their cardiovascular and neurological effects. Addressing the long-term consequences of MNP exposure necessitates interdisciplinary collaboration to enhance comprehension and alleviate their growing risk to human health.

Microplastic pollution: a review of specific blood-tissue barrier breaches and health effects

Microplastic (1 μm - 5 mm) and nanoplastic (<1 μm) pollution is a heightening global challenge affecting the environment and the health of living creatures within. As primary precursors for plastic manufacturing, microplastics predominantly get into the environment through plastic product degradation and integrate into water, food chain and consumer products leading to potential health consequences. The mammalian system is equipped with several blood-tissue barriers with exclusive tight junctions that selectively regulate material transfer and protect vulnerable and functionally important organs. Nonetheless, emerging evidence indicates microplastics interact, traverse and compromise the integrity of these complex barriers. This review summarises the known and potential impact of microplastics on human health, focusing on specific organ barrier breaches. Evidence of microplastic traversal and deposition in distal mammalian organs are discussed. We further highlight current challenges facing both researchers and clinicians and provide an outlook for expanding our understanding of the impact of microplastic on health.

Preparation of dual mode spectroscopic system for testing: Analysis of sample holder and investigation of intensity noise

Absorption spectroscopy is combined with the principle of multiple wavelengths to develop a biomedical sensing mechanism, laid by two Fibre Bragg Gratings. It is essential to incorporate a sample holder in the setup in which the substances can be tested, necessitating its complete investigation without and with the holder, in both directions. The average losses of the fibre junctions are 0.44 and 0.18 dB, respectively, with accuracy of ±0.2 dB which lies within the intensity profile specified by the manufacturer (0.3 dB). Next, the spectral profiles and its respective factors (slope, threshold, mode spacing, intensity levels) of both systems are compared and thoroughly investigated on technical grounds, to examine any anticipated issues for the sensor's operation. Afterwards, we place the holder in the laser setup and check its efficiency by comparing it the intensity profiles of the system without it, under identical parametric values. The average Relative Intensity Noise is found to be consistently low and analogous in both setups, with scientific justifications. Repetition in the forward and reverse directions, and swapping the positions of the lenses, the outcomes show homogenous patterns, which provides conclusive approval with specified parametric regulations in this work.

Medical exposure to micro(nano)plastics: An exposure pathway with potentially significant harm to human health that should not be overlooked

Micro(nano)plastics (MNPs) are an emerging type of contaminants that are widely present in the environments that people live in. MNPs can enter the human body in a variety of pathways, but the three main ones are through dietary intake, air inhalation, and skin contact. However, it has been discovered that medical plastics used in medical activities also pose potential risks to MNPs exposure as exposure pathways are continuously refined and clarified. Unfortunately, there is currently insufficient study on the exposure of medical plastics and MNPs, and exposure risks and potential health problems are frequently overlooked. This study aimed to close this research gap by searching the databases of China National Knowledge Infrastructure (CNKI), PubMed, and Web of Science for relevant literature. It then filtered out publications that contained information relevant to keywords such as micro(nano)plastics, medical plastics, exposure pathways, and human health in order to do analysis and summary. We discovered that medical plastics are a high-risk source of direct MNPs exposure to the human body, and this exposure could pose a potential harm to human health. Because of the potential harm to human health, this work presents the medical exposure of MNPs for the first time and calls for more research and attention on this vital area.

Microplastics, as a risk factor in the development of interstitial lung disease- a preliminary study

Microplastic (MPs) pollution is a global concern that affects all living organisms, yet research on MP-related disorders in humans, including incidence and symptoms, remains limited. In this study, the presence, composition, and characterization of MPs in bronchoalveolar lavage (BAL), which reflects lung tissue, and blood were examined. Fiberoptic bronchoscopy was performed to collect BAL samples from patients suspected of having interstitial lung disease (ILD) as well as from a control group. MPs were identified and measured using μ-Raman techniques. In BAL samples, the most common MPs color observed was grey/white, with sizes ranging from 4.19 to 792.00 μm. The particle shapes and polymer types identified included polyamide (PA), polyester (PET), polyvinyl chloride (PVC), and polyurethanes (PU). For blood samples, MPs were predominantly grey/white and blue, with sizes ranging from 13.14 to 20. 29 μm. The identified polymers in blood samples included polyamide (PA) and polyethylene (PE). MPs were detected in 10 out of 18 patients (55%) suspected of having ILD, with most of these patients presenting with the fibrotic type of the disease. In the control group, two patients whose BAL samples were positive for MPs were found to have chronic lung disease. This study is the first to explore the relationship between interstitial lung disease (ILD) and microplastics (MPs), revealing a tendency for the presence of MPs in the bronchoalveolar lavage (BAL) of ILD patients, particularly those with a fibrotic phenotype. Further research is needed to determine the cumulative effects of MPs on human health, especially concerning the respiratory system, which is highly exposed to environmental pollutants.

Measurement of Microplastic Release After the Use of Polypropylene Nasal Irrigation Bottles

OBJECTIVES

Microplastics originating from plastic materials may pose risks to human health. This study investigated the presence of microplastics in nasal irrigation fluids collected from reused bottles, focusing on the duration of bottle usage.

METHODS

Readily available nasal irrigation bottles made of polypropylene were purchased. Unused bottles served as controls. Test samples were prepared to simulate 1-, 3-, and 6-month reuse. Nasal irrigation fluid samples (n=12) were collected from each set of bottles: three from the new control bottles and nine from the bottles simulating 1-, 3-, and 6-month reuse. Raman spectroscopy was used to detect microplastics in the nasal irrigation samples, and the results were compared based on the duration of bottle use.

RESULTS

An average of 33.00±20.42 microplastic particles per 300 mL was detected in the nasal irrigation fluid from the control bottles. In comparison, bottles used for 1, 3, and 6 months contained averages of 68.66±30.07, 261.66±20.59, and 204.33±52.16 microplastic particles per 300 mL, respectively. The majority of these particles ranged in size from 10 to 100 μm and were primarily fragment-shaped. Polypropylene was identified as the predominant type of microplastic, suggesting it was directly released from the irrigation bottles.

CONCLUSION

We detected microplastics in nasal irrigation fluids, which likely originated from the repeated use of nasal irrigation bottles. The quantity of microplastics was significantly higher in samples from bottles simulating 3 months of use compared to the control samples. Therefore, we recommend the development of guidelines to regulate the duration of nasal irrigation bottle usage to reduce microplastic infiltration into the body via the sinonasal cavity.

Microplastic and plastic pollution: impact on respiratory disease and health

Throughout their lifecycle, from production to use and upon disposal, plastics release chemicals and particles known as micro- and nanoplastics (MNPs) that can accumulate in the environment. MNPs have been detected in different locations of the human body, including in our lungs. This is likely a consequence of MNP exposure through the air we breathe. Yet, we still lack a comprehensive understanding of the impact that MNP exposure may have on respiratory disease and health. In this review, we have collated the current body of evidence on the implications of MNP inhalation on human lung health from in vitro, in vivo and occupational exposure studies. We focused on interactions between MNP pollution and different specific lung-resident cells and respiratory diseases. We conclude that it is evident that MNPs possess the capacity to affect lung tissue in disease and health. Yet, it remains unclear to which extent this occurs upon exposure to ambient levels of MNPs, emphasising the need for a more comprehensive evaluation of environmental MNP exposure levels in everyday life.

Characteristics and removal efficiency of microplastics at secondary wastewater treatment plant in Lithuania

Wastewater treatment plants (WWTPs) are the most significant barrier between anthropogenic microplastics and environmental ecosystems. The distribution and characteristics of microplastics in WWTPs remain uncertain and incompletely understood, particularly in northeastern Europe (Baltic States), where there is a lack of data on microplastic pollution and distribution. This study presents the removal efficiency and variation in characteristics of microplastics in different stages of the secondary WWTP during a 3-month sampling campaign in Lithuania. The abundance, size, shape, color, and chemical composition of microplastics in the wastewater at different treatment stages were thoroughly examined, in a size range from 20 to 1000 μm. On average, 2962 ± 25 particles/L of microplastic enter the studied WWTP. The obtained microplastic removal efficiency was 55.4% ± 3.9%, highlighting the necessity to enhance wastewater treatment strategies focusing on microplastic removal. Fragment-type microplastics smaller than 100 μm were removed from wastewater samples with the highest removal efficiency. Furthermore, our study includes recommendations to improve microplastic removal efficiency and contribute to mitigating microplastic pollution. PRACTITIONER POINTS: A large number of MPs in the size range of 20-1000 μm enter Lithuanian WWTP. Small-sized MPs within a range of 20-50 μm and 50-100 μm were removed with the highest efficiency of 54.07 ± 1.68% and 56.4 ± 2.43%, respectively. The shape and size of MPs have a major impact on the efficiency of their removal. Future research should prioritize the development of economical and energy-efficient systems, specifically designed for the removal of MPs in WWTPs.