Human biomonitoring of microplastics and health implications: A review

The boom era of emerging contaminants: A review of remediating agricultural soils by biochar

Emerging contaminants (ECs) are widely sourced persistent pollutants that pose a significant threat to the environment and human health. Their footprint spans global ecosystems, making their remediation highly challenging. In recent years, a significant amount of literature has focused on the use of biochar for remediation of heavy metals and organic pollutants in soil and water environments. However, the use of biochar for the remediation of ECs in agricultural soils has not received as much attention, and as a result, there are limited reviews available on this topic. Thus, this review aims to provide an overview of the primary types, sources, and hazards of ECs in farmland, as well as the structure, functions, and preparation types of biochar. Furthermore, this paper emphasizes the importance and prospects of three remediation strategies for ECs in cropland: (i) employing activated, modified, and composite biochar for remediation, which exhibit superior pollutant removal compared to pure biochar; (ii) exploring the potential synergistic efficiency between biochar and compost, enhancing their effectiveness in soil improvement and pollution remediation; (iii) utilizing biochar as a shelter and nutrient source for microorganisms in biochar-mediated microbial remediation, positively impacting soil properties and microbial community structure. Given the increasing global prevalence of ECs, the remediation strategies provided in this paper aim to serve as a valuable reference for future remediation of ECs-contaminated agricultural lands.

A self-cleaning micro-fluidic chip biospired by the filtering system of manta rays

Size-based particle filtration has become indispensable in numerous biomedical and environmental applications. In this study, bioinspired by the filter-feeding mechanism (lobe filtration) of manta rays, we designed a U-shaped biomimetic gill rake filter that combined lobe filtration and Dean flow to filter monodisperse suspensions, bi-disperse suspensions and yeast cells. Compared with other equipment using the inertial focusing technology, our equipment can perform high-throughput (up to 8 mL min-1) and high-efficiency filtration of particles (maximum filtration efficiencies of 96.08% and 97.14% for 10 and 15 μm monodisperse suspensions at the optimum flow rate of 6 mL min-1). The complex velocity field of the micro-fluidic flow within the filter is numerically simulated, and in combination with experiments, a threshold for the flow rate is identified. When the inlet flow rate exceeds the threshold value, the efficiency of particle filtration is increased rapidly. Afterwards, by analysing the filtration mechanism, we develop three novel filtration processes. The equilibrium positions of the particles and yeast cells in the main channel are close to the outer wall at high flow rate, which diminishes the likelihood of particles and yeast cells entering the side channel. This configuration establishes a self-cleaning mechanism, ensuring prolonged and efficient operation of the filter with high-throughput processing. Furthermore, the influence of the filter lobe angle and channel width on the filtration efficiency and outlet flow rate ratio are explored, and an optimisation plan is prepared.

Microplastic prevalence and human exposure in the bottled drinking water in the west Godavari region of Andhra Pradesh, India

Microplastics (MPs) are widespread, minute plastic particles present in various aquatic environments, raising concerns about their effect on human health and ecosystems. The detrimental effects of MPs on the environment, include the contamination of ecosystems, harm to aquatic life through ingestion, potential disruption of food chains, and long-term ecological consequences. Despite numerous studies confirming the MP's presence in aquatic environments, research specifically focused on MPs in bottled drinking water (BDW) is limited. Research on MPs in drinking water is vital to assess potential health risks and develop strategies for ensuring water safety and quality. This study fills a research gap by investigating microplastics (MPs) in nine brands of BDW in the West Godavari region of Andhra Pradesh, India. The average MP concentration in BDW was found to be 2.89 ± 0.48 items/L, with fibers being the predominant shape and sizes ranging from 500 to 1000 μm. Transparent and blue were the most common colors. From ATR-FTIR analysis, the dominant polymer found was polypropylene (PP) followed by polyethylene terephthalate (PET). The human risk assessment was also calculated using the formula of Estimated daily intake (EDI) and Lifetime intake (LTI). The calculation found that the EDI of MPs for children and adults ranged from 0.041 to 0.291 MPs per kilogram per day and 0.019 to 0.133 MPs per kilogram per day, respectively. The mean LTI of MP consumption of an individual, ranged from 17,958 to 2,54,861 MPs, considering an average age of 75 years. The current findings offer valuable information for ongoing evaluations of the potential human risks linked to MP exposure.

Health assessment based on exposure to microplastics in tropical agricultural soil

Microplastic (MP) pollution of agricultural soils has caused global alarm over its widespread distribution and potential risks to terrestrial ecosystems and human health. This study assessed human health based on exposure to soil MPs through a comprehensive investigation of the factors influencing their occurrence and spatial distribution on Hainan Island, South China. The results showed that the abundance of soil MPs was 1128.6 ± 391.5 items·kg-1, whereas the normalized abundance of MPs based on using a power-law function was 19,261.4 items·kg-1. Regarding the extent of population exposure to agricultural soil MPs, the average daily exposure dose (pADD) model revealed that using mass as an indicator to assess the health risks associated with MP intake is more reliable than using abundance. However, abundance-based exposure assessments are also relevant because MPs with smaller particle sizes are more harmful to human health. Moreover, for adults, the normalized pADD values based on abundance and mass were 1.68E-02 item MPs·kg BW-1·d-1 and 7.23E-02 mg MPs·kg BW-1·d-1, respectively. Although the multidimensionality of MPs should be further aligned and quantified, the preliminary findings of this study contribute to the development of human health risk assessment frameworks for soil MPs.

Maternal exposure to polystyrene nanoplastics causes defective retinal development and function in progeny mice by disturbing metabolic profiles

Microplastics (MPs) and nanoplastics (NPs) are widely spreading in our living environment, accumulating in the human body and potentially threating human health. The retina, which is a terminally differentiated extension of the central nervous system, is essential for the visual system. However, the effects and molecular mechanisms of MPs/NPs on retina development and function are still unclear. Here, we investigated the effects and modes of action of polystyrene NPs (PS-NPs) on the retina using mice as a mammalian model species. Maternal PS-NP exposure (100 nm) at an environmentally realistic concentration of 10 mg L-1 (or 2.07 *1010 particles mL-1) via drinking water from the first day of pregnancy till the end of lactation (21 days after birth) caused defective neural retinal development in the neonatal mice, by depositing in the retinal tissue and reducing the number of retinal ganglion cells and bipolar cells. Exposure to PS-NPs retarded retinal vascular development, while abnormal electroretinogram (ERG) responses and an increased level of oxidative stress were also observed in the retina of the progeny mice after maternal PS-NP exposure. Metabolomics showed significant dysregulation of amino acids that are pivotal to neuron retinal function, such as glutamate, aspartate, alanine, glycine, serine, threonine, taurine, and serotonin. Transcriptomics identified significantly dysregulated genes, which were enriched in processes of angiogenesis, visual system development and lens development. Regulatory analysis showed that Fos gene mediated pathways could be a potential key target for PS-NP exposure in retinal development and function. Our study revealed that maternal exposure to PS-NPs generated detrimental effects on retinal development and function in progeny mice, offering new insights into the visual toxicity of PS-NPs.

Detection and quantification of various microplastics in human endometrium based on laser direct infrared spectroscopy

The pollution of microplastics (MPs) has received widespread attention with the increasing usage of plastics in recent years. MPs could enter the human body and exist in the circulatory system. Endometrium, with rich blood vessels, acts as an essential role in human health and female fertility. However, there is no study reporting the MPs exposure in human endometrium. We collected the endometrium samples to detect the presence of MPs qualitatively and quantitatively via laser direct infrared. We found that there was a total of 13 types of MPs existing in the collected samples, among which 6 special types of MPs were with both high abundance and high detection rate. The abundance of these MPs ranged from 0 to 117 particles/100 mg, with a median abundance of 21 particles/100 mg. Most detected MPs, accounting for 88.35 %, were in small size (20-100 μm). Among small-size MPs, ethylene-acrylic acid copolymer ranked first while polyethylene accounted for the largest proportion among large-size MPs (100-500 μm). Correlation analysis indicated there was no significant relationship between age and MP abundance or BMI and MP abundance. We also designed a questionnaire to investigate lifestyle and daily habits, aiming at revealing the potential relationship between MP exposure and living habits. We discovered that some drinking habits and chewing gum were significantly correlated with a higher level of MP exposure. For the first time, we identified the presence of MPs in human endometrium and clarified the potential connections between MP exposure and lifestyle. Further studies are still necessary to explore more underlying information.