Navigating the nexus: climate dynamics and microplastics pollution in coastal ecosystems.

Microplastics (MPs) pollution is an emerging environmental health concern, impacting soil, plants, animals, and humans through their entry into the food chain via bioaccumulation. Human activities such as improper solid waste dumping are significant sources that ultimately transport MPs into the water bodies of the coastal areas. Moreover, there is a complex interplay between the coastal climate dynamics, environmental factors, the burgeoning issue of MPs pollution and the complex web of coastal pollution. We embark on a comprehensive journey, synthesizing the latest research across multiple disciplines to provide a holistic understanding of how these inter-connected factors shape and reshape the coastal ecosystems. The comprehensive review also explores the impact of the current climatic patterns on coastal regions, the intricate pathways through which MPs can infiltrate marine environments, and the cascading effects of coastal pollution on ecosystems and human societies in terms of health and socio-economic impacts in coastal regions. The novelty of this review concludes the changes in climate patterns have crucial effects on coastal regions, proceeding MPs as more prevalent, deteriorating coastal ecosystems, and hastening the transfer of MPs. The continuous rising sea levels, ocean acidification, and strong storms result in habitat loss, decline in biodiversity, and economic repercussion. Feedback mechanisms intensify pollution effects, underlying the urgent demand for environmental conservation contribution. In addition, the complex interaction between human, industry, and biodiversity demanding cutting edge strategies, innovative approaches such as remote sensing with artificial intelligence for monitoring, biobased remediation techniques, global cooperation in governance, policies to lessen the negative socioeconomic and environmental effects of coastal pollution.

The dosage- and size-dependent effects of micro- and nanoplastics in lettuce roots and leaves at the growth, photosynthetic, and metabolomics levels.

The occurrence of microplastics (MPs) and nanoplastics (NPs) in soils potentially induce morphological, physiological, and biochemical alterations in plants. The present study investigated the effects of MPs/NPs on lettuce (Lactuca sativa L. var. capitata) plants by focusing on (i) four different particle sizes of polyethylene micro- and nanoplastics, at (ii) four concentrations. Photosynthetic activity, morphological changes in plants, and metabolomic shifts in roots and leaves were investigated. Our findings revealed that particle size plays a pivotal role in influencing various growth traits of lettuce (biomass, color segmentation, greening index, leaf area, and photosynthetic activity), physiological parameters (including maximum quantum yield - Fv/Fmmax, or quantum yield in the steady-state Fv/FmLss, NPQLss, RfdLss, FtLss, FqLss), and metabolomic signatures. Smaller plastic sizes demonstrated a dose-dependent impact on aboveground plant structures, resulting in an overall elicitation of biosynthetic processes. Conversely, larger plastic size had a major impact on root metabolomics, leading to a negative modulation of biosynthetic processes. Specifically, the biosynthesis of secondary metabolites, phytohormone crosstalk, and the metabolism of lipids and fatty acids were among the most affected processes. In addition, nitrogen-containing compounds accumulated following plastic treatments. Our results highlighted a tight correlation between the qPCR analysis of genes associated with the soil nitrogen cycle (such as NifH, NirK, and NosZ), available nitrogen pools in soil (including NO3- and NH4), N-containing metabolites and morpho-physiological parameters of lettuce plants subjected to MPs/NPs. These findings underscore the intricate relationship between specific plastic contaminations, nitrogen dynamics, and plant performance.

[Screening of quality markers and activity verification of Glycyrrhizae Radix et Rhizoma based on small molecule compound-protein interaction].

In order to solve the problem of weak correlation between quality control components and efficacy of Glycyrrhizae Radix et Rhizoma, this study detected the interaction between small molecular chemical components of Glycyrrhizae Radix et Rhizoma and total proteins of various organs of mice by fluorescence quenching method to screen potential active components. The 27 chemical components in Glycyrrhizae Radix et Rhizoma were detected by HPLC and their deletion rates in 34 batches of Glycyrrhizae Radix et Rhizoma were calculated. Combined with the principle of component effectiveness and measurability, the potential quality markers(Q-markers) of Glycyrrhizae Radix et Rhizoma were screened. RAW264.7 macrophage injury model was induced by microplastics. The cell viability and nitric oxide content were detected by CCK-8 and Griess methods. The levels of inflammatory factors(TNF-α, IL-1ß, IL-6, CRP) and oxidative stress markers(SOD, MDA, GSH) were detected by the ELISA method to verify the activity of Q-markers. It was found that the interaction strength between different chemical components and organ proteins in Glycyrrhizae Radix et Rhizoma was different, reflecting different organ selectivity and 18 active components were screened out. Combined with the signal-to-noise ratio of the HPLC chromatographic peaks and between-run stability of the components, seven chemical components such as liquiritin apioside, liquiritin, isoliquiritin apioside, isoliquiritin, liquiritigenin, isoliquiritigenin and ammonium glycyrrhizinate were finally screened as potential Q-markers of Glycyrrhizae Radix et Rhizoma. In vitro experiments showed that Q-markers of Glycyrrhizae Radix et Rhizoma could dose-dependently alleviate RAW264.7 cell damage induced by microplastics, inhibit the secretion of inflammatory factors, and reduce oxidative stress. Under the same total dose, the combination of various chemical components could synergistically enhance anti-inflammatory and antioxidant effects compared with the single use. This study identified Q-markers related to the anti-inflammatory and antioxidant effects of Glycyrrhizae Radix et Rhizoma, which can provide a reference for improving the quality control standards of Glycyrrhizae Radix et Rhizoma.

Revealing the metabolomics and biometrics underlying phytotoxicity mechanisms for polystyrene nanoplastics and dibutyl phthalate in dandelion (Taraxacum officinale).

Micro/nanoplastics (M/NPs) and phthalates (PAEs) are emerging pollutants. Polystyrene (PS) MPs and dibutyl phthalate (DBP) are typical MPs and PAEs in the environment. However, how dandelion plants respond to the combined contamination of MPs and PAEs remains unclear. In this study, we evaluated the individual and combined effects of PS NPs (10 mg L-1) and DBP (50 mg L-1) on dandelion (Taraxacum officinale) seedlings. The results showed that compared to control and individual-treated plants, coexposure to PS NPs and DBP significantly affected plant growth, induced oxidative stress, and altered enzymatic and nonenzymatic antioxidant levels of dandelion. Similarly, photosynthetic attributes and chlorophyll fluorescence kinetic parameters were significantly affected by coexposure. Scanning electron microscopy (SEM) results showed that PS particles had accumulated in the root cortex of the dandelion. Metabolic analysis of dandelion showed that single and combined exposures caused the plant's metabolic pathways to be profoundly reprogrammed. As a consequence, the synthesis and energy metabolism of carbohydrates, amino acids, and organic acids were affected because galactose metabolism, the citric acid cycle, and alanine, aspartic acid and glutamic acid metabolism pathways were significantly altered. These results provide a new perspective on the phytotoxicity and environmental risk assessment of MPs and PAEs in individual or coexposures.

Effects of microplastics on the phytoremediation of Cd, Pb, and Zn contaminated soils by Solanum photeinocarpum and Lantana camara.

Microplastics are emerging pollutants and have become a global environmental issue. The impacts of microplastics on the phytoremediation of heavy metal-contaminated soils are unclear. A pot experiment was conducted to investigate the effects of four additions (0, 0.1%, 0.5%, and 1% w·w-1) of polyethylene (PE) and cadmium (Cd), lead (Pb), and zinc (Zn) contaminated soil on the growth and heavy metal accumulation of two hyperaccumulators (Solanum photeinocarpum and Lantana camara). PE significantly decreased the pH and activities of dehydrogenase and phosphatase in soil, while it increased the bioavailability of Cd and Pb in soil. Peroxidase (POD), catalase (CAT), and malondialdehyde (MDA) activity in the plant leaves were all considerably increased by PE. PE had no discernible impact on plant height, but it did significantly impede root growth. PE affected the morphological contents of heavy metals in soils and plants, while it did not alter their proportions. PE increased the content of heavy metals in the shoots and roots of the two plants by 8.01-38.32% and 12.24-46.28%, respectively. However, PE significantly reduced the Cd extraction amount in plant shoots, while it significantly increased the Zn extraction amount in the plant roots of S. photeinocarpum. For L. camara, a lower addition (0.1%) of PE inhibited the extraction amount of Pb and Zn in the plant shoots, but a higher addition (0.5% and 1%) of PE stimulated the Pb extraction amount in the plant roots and the Zn extraction amount in the plant shoots. Our results indicated that PE microplastics have negative effects on the soil environment, plant growth, and the phytoremediation efficiency of Cd and Pb. These findings contribute to a better knowledge of the interaction effects of microplastics and heavy metal-contaminated soils.

Effects of land use on the distribution of soil microplastics in the Lihe River watershed, China.

Soil contamination by microplastics (MPs) has gained widespread attention, whose fate may be influenced by land use types. The effects of land use types and the intensity of human activities on the distribution and sources of soil MPs at the watershed scale are unclear. In this study, 62 surface soil sites in representing five land use types (urban, tea garden, dryland, paddy field and woodland) and 8 freshwater sediment sites were investigated in the Lihe River watershed. MPs were detected in all samples, and the average abundance of soil and sediments was 401.85 ± 214.02 and 222.13 ± 54.66 items/kg, respectively. The soil MPs abundance followed the sequence: urban > paddy field > dryland > tea garden > woodland. Soil MP distribution and MP communities were significant different (p < 0.05) among land use types. The similarity of MP community highly correlated with geographic distance, and woodlands and freshwater sediments may be a potential fate for MPs in the Lihe River watershed. Soil clay, pH, and bulk density significantly correlated with MP abundance and fragment shape (p < 0.05). The positive correlation between population density, Total- Point of Interest (POI) and MP diversity indicates the importance of intensity of human activities in exacerbating soil MP pollution (p < 0.001). Plastic waste sources accounted for 65.12%, 58.60%, 48.15% and 25.35% of MPs in urban, tea garden, dryland and paddy field soils, respectively. Differences in the intensity of agricultural activities and cropping patterns were associated with different percentages of mulching film sources in the three types of agricultural soils. This study provides new ideas for the quantitative analysis of soil MP sources in different land use types.

Microplastics composition and load from three wastewater treatment plants discharging into Mersin Bay, north eastern Mediterranean Sea.

Copious quantities of microplastics enter the sewage system on a daily basis, and hence wastewater treatment plants (WWTPs) could be an important source of microplastic pollution in coastal waters. Influent and effluent discharges from three WWTPs in Mersin Bay, Turkey were sampled at monthly intervals over a one-year period during 2017. When data from all WWTPs were combined, fibers constituted the dominant particle form, accounting for 69.7% of total microplastics. Although notable oscillations in microplastic particle concentrations were observed throughout the year influent waters on average contained about 2.5-fold greater concentrations of microplastics compared to the effluent waters. An average of 0.9 microplastic particles were found per liter of effluent from the three WWTPs amounting to around 180 × 106 particles per day to Mersin Bay. This shows that despite their ability to remove 55-97% of microplastics, WWTPs are one of the main sources of microplastics to the northeast Mediterranean Sea.

Holistic assessment of microplastics in various coastal environmental matrices, southwest coast of India.

Plastics in the marine environment are introduced through multiple pathways, and pose serious threats to aquatic biota. Recently microplastic pollution and its possible consequences in India have been recognized by the scientific community, however the extent of the crisis has not yet been quantified. The present study attempted to ascertain the abundance, distribution and characteristics of microplastics in coastal waters (14 locations), beach sediments (22 locations) and marine fishes (11 locations) from the state of Kerala, southwest coast of India. The results showed that the mean microplastic abundance was 1.25 ±â€¯0.88 particles/m3 in coastal waters and 40.7 ±â€¯33.2 particles/m2 in beach sediments with higher concentrations in the southern coast of the state. The abundance of microplastics, mostly contributed by fragments, fibre/line and foam, in both coastal waters and beach sediments, were highly influenced by river runoff and proximity to urban agglomeration. Fourier Transform Infrared Spectroscopy-Attenuated Total Reflection (FTIR-ATR) revealed that polyethylene (PE) and polypropylene (PP) were the dominant polymers in the marine environment. The digestive tracts of 15 out of 70 commercially important fishes studied, contained 22 microplastic particles. Polyethylene (PE; 38.46%) followed by cellulose (CE; 23.08%), rayon (RY; 15.38%), polyester (PL; 15.38%) and polypropylene (PP; 7.69%) were the major contributors in the fish ingested microplastic composition. A broad range of heavy metals, metalloids and other elements that are potentially indicative of hazardous chemicals were present in microplastics collected from the beaches of Kerala. These results enhance our understanding on the sources, transport pathways and the associated environmental risks of microplastics to marine ecosystems.

Microplastics in the crustaceans Nephrops norvegicus and Aristeus antennatus: Flagship species for deep-sea environments?

Ingestion of microplastics (MPs) has been documented in several marine organisms, but their occurrence in deep-sea species remains almost unknown. In this study, MPs were investigated in two economically and ecologically key crustaceans of the Mediterranean Sea, the Norwegian lobster Nephrops norvegicus and the shrimp Aristeus antennatus. Both the species were collected from 14 sites around Sardinia Island, at depths comprised between 270 and 660 m. A total of 89 and 63 stomachs were analysed for N. norvegicus and A. antennatus respectively, and more than 2000 MPs-like particles were extracted and sorted for identification and characterization by µFT-IR. In N. norvegicus, 83% of the specimens contained MPs, with an average abundance of 5.5 ±â€¯0.8 MPs individual-1, while A. antennatus showed a lower frequency of ingestion (67%) and a lower mean number of MPs (1.66 ±â€¯0.1 MPs individual-1). Composition and size of particles differed significantly between the two species. The non-selective feeding strategy of N. norvegicus could explain the 3-5 folds higher numbers of MPs in its stomach, which were mostly composed of films and fragments derived by polyethylene and polypropylene single-use plastic items. Contrarily, most MPs in the stomachs of A. antennatus were polyester filaments. The MPs abundance observed in N. norvegicus is among the highest detected in Mediterranean species considering both fish and invertebrates species, and provides novel insights on MPs bioavailability in deep-sea habitats. The overall results suggest that both N. norvegicus and A. antennatus, easily available in common fishery markets, could be valuable bioindicators and flagship species for plastic contamination in the deep-sea.