Microplastics and Nanoplastics Effects on Plant-Pollinator Interaction and Pollination Biology

Microplastic ingestion and co-exposure to Nosema ceranae and flupyradifurone reduce the survival of honey bees (Apis mellifera L.)

Bees are exposed to several threats, including pathogens (i.e. Nosema ceranae), pesticides and environmental contaminants. The new insecticide flupyradifurone, and the microplastics in the environment, have raised significant concerns on bee health. This study evaluated the simultaneous effects of microplastics, flupyradifurone, and N. ceranae on honey bee health, focusing on survival rates, N. ceranae replication, daily food consumption, and bee midgut histological alterations. Results showed a significant decrease in bee longevity across all treatments compared to the control, with the combination of flupyradifurone, microplastics, and N. ceranae having the most severe impact. Microplastics and flupyradifurone exposure also increased N. ceranae proliferation, especially in bees subjected to both stressors. Histological analysis revealed reduced regenerative cell nests in the midgut and changes in the nuclear matrix, indicating stress responses. Overall, the simultaneous presence of both biotic and abiotic stressors in nature can synergistically interact, leading to harmful effects on bees.

Plastic pollution in agricultural landscapes: an overlooked threat to pollination, biocontrol and food security

Ecosystem services such as pollination and biocontrol may be severely affected by emerging nano/micro-plastics (NMP) pollution. Here, we synthesize the little-known effects of NMP on pollinators and biocontrol agents on the organismal, farm and landscape scale. Ingested NMP trigger organismal changes from gene expression, organ damage to behavior modifications. At the farm and landscape level, NMP will likely amplify synergistic effects with other threats such as pathogens, and may alter floral resource distributions in high NMP concentration areas. Understanding exposure pathways of NMP on pollinators and biocontrol agents is critical to evaluate future risks for agricultural ecosystems and food security.

Micro and nanoplastics pollution: Sources, distribution, uptake in plants, toxicological effects, and innovative remediation strategies for environmental sustainability

Microplastics and nanoplastics (MNPs), are minute particles resulting from plastic fragmentation, have raised concerns due to their widespread presence in the environment. This study investigates sources and distribution of MNPs and their impact on plants, elucidating the intricate mechanisms of toxicity. Through a comprehensive analysis, it reveals that these tiny plastic particles infiltrate plant tissues, disrupting vital physiological processes. Micro and nanoplastics impair root development, hinder water and nutrient uptake, photosynthesis, and induce oxidative stress and cyto-genotoxicity leading to stunted growth and diminished crop yields. Moreover, they interfere with plant-microbe interactions essential for nutrient cycling and soil health. The research also explores the translocation of these particles within plants, raising concerns about their potential entry into the food chain and subsequent human health risks. The study underscores the urgency of understanding MNPs toxicity on plants, emphasizing the need for innovative remediation strategies such as bioremediation by algae, fungi, bacteria, and plants and eco-friendly plastic alternatives. Addressing this issue is pivotal not only for environmental conservation but also for ensuring sustainable agriculture and global food security in the face of escalating plastic pollution.

More than just sweet: current insights into microplastics in honey products and a case study of Melipona quadrifasciata honey

Honey, traditionally known as a pure and natural substance, has become an unexpected reservoir for microplastic contamination. This study consisted of an experimental investigation to assess the occurrence of microplastics in honey produced by Melipona quadrifasciata, a native bee species in Brazil. Our investigation covers eight areas (one sample per area), including built and vegetated areas located in São Paulo city, Brazil, to understand the distribution of microplastics in these environments. Honey samples (10 mL) were collected using a syringe and sent to the laboratory for further analysis. Microplastics extracted from honey samples were characterized under a stereomicroscope to determine their size, color, and morphology. Also, the polymer type was determined by FTIR analysis. All honey samples (100%) showed microplastics. The predominant particles displayed a fiber shape with a size below 299 μm and a transparent color and were primarily composed of polypropylene. Their concentrations ranged from 0.1 to 2.6 particles per mL of honey, raising concerns about their potential impact on bee populations and human consumers. This study underscores the need for further research on the sources and implications of microplastic contamination in Melipona quadrifasciata honey, shedding light on the broader issue of environmental plastic pollution and its impact on pollinators.

Exploring the risk of microplastics to pollinators: focusing on honey bees

The rapid increase in global plastic production and usage has led to global environmental contamination, with microplastics (MPs) emerging as a significant concern. Pollinators provide a crucial ecological service, while bee populations have been declining in recent years, and MPs have been recognized as a new risk factor contributing to their losses. Despite the pervasive distribution and persistence of MPs, understanding their risks to honey bees remains a critical knowledge gap. This review summarizes recent studies that investigate the toxicity of MPs on honey bee health from different perspectives. The findings revealed diverse and material-/size-/dosage-dependent outcomes, emphasizing the need for comprehensive assessments in the follow-up studies. MPs have been detected in honey and in bees' organs (e.g., gut and brain), posing potential threats to bee fitness, including altered behavior, cognitive abilities, compromised immunity, and dysfunction of the gut microbiota. It should be noticed that despite several laboratory studies suggesting the aforementioned adverse effects of MPs, field/semi-field experiments are still warranted. The synergistic toxicity of MPs with other environmental contaminants (pesticides, antibiotics, fungicides, heavy metals, etc.) still requires further investigation. Our review highlights the critical need to understand the relationships between MPs, pollinators, and the ecosystem to mitigate potential risks and ensure the sustainability of vital services provided by honey bees.

The Plasticene era: Current uncertainties in estimates of the hazards posed by tiny plastic particles on soils and terrestrial invertebrates

Plastics are ubiquitous in our daily life. Large quantities of plastics leak in the environment where they weather and fragment into micro- and nanoparticles. This potentially releases additives, but rarely leads to a complete mineralization, thus constitutes an environmental hazard. Plastic pollution in agricultural soils currently represents a major challenge: quantitative data of nanoplastics in soils as well as their effects on biodiversity and ecosystem functions need more attention. Plastic accumulation interferes with soil functions, including water dynamics, aeration, microbial activities, and nutrient cycling processes, thus impairing agricultural crop yield. Plastic debris directly affects living organisms but also acts as contaminant vectors in the soils, increasing the effects and the threats on biodiversity. Finally, the effects of plastics on terrestrial invertebrates, representing major taxa in abundance and diversity in the soil compartment, need urgently more investigation from the infra-individual to the ecosystem scales.

Polystyrene nanoplastics induce vascular stenosis via regulation of the PIWI-interacting RNA expression profile

Nanoplastics (NPs) have become common worldwide and attracted increasing attention due to their serious toxic effects. Owing to their higher surface area and volume ratios and ability to easily enter tissues, NPs impose more serious toxic effects than microplastics. However, the effect of NP exposure on vascular stenosis remains unclear. To measure the effects of polystyrene NP (PS-NP) exposure on vascular toxicity, we conducted analyses of blood biochemical parameters, pathological histology, high-throughput sequencing, and bioinformatics. Red fluorescent PS-NPs (100 nm) were effectively uptake by mouse vascular arterial tissue. The uptake of PS-NPs resulted in vascular toxicity, including alterations in lipid metabolism and thickening of the arterial wall. Based on PIWI-interacting RNA (piRNA) sequencing, 1547 and 132 differentially expressed piRNAs (DEpiRNAs) were detected in the PS-NP treatment group after 180 and 30 days, including 787 and 86 upregulated and 760 and 46 downregulated compared with the control group, respectively. Gene Ontology and Kyoto Encyclopedia of Genes and Genomes enrichment analyses indicated that the target genes of DEpiRNAs were mostly involved in cell growth and cell motility-related signaling, such as the MAPK signaling pathway. This is the first study to highlight the alteration in piRNA levels in mouse vascular arterial tissue after PS-NP exposure. This study adds to the knowledge regarding the regulatory mechanism of pathological changes induced by PS-NP exposure.

Co-exposure to polystyrene nanoplastics and triclosan induces synergistic cytotoxicity in human KGN granulosa cells by promoting reactive oxygen species accumulation

In recent years, nanoplastics (NPs) and triclosan (TCS, a pharmaceutical and personal care product) have emerged as environmental pollution issues, and their combined presence has raised widespread concern regarding potential risks to organisms. However, the combined toxicity and mechanisms of NPs and TCS remain unclear. In this study, we investigated the toxic effects of polystyrene NPs and TCS and their mechanisms on KGN cells, a human ovarian granulosa cell line. We exposed KGN cells to NPs (150 μg/mL) and TCS (15 μM) alone or together for 24 hours. Co-exposure significantly reduced cell viability. Compared with exposure to NPs or TCS alone, co-exposure increased reactive oxygen species (ROS) production. Interestingly, co-exposure to NPs and TCS produced synergistic effects. We examined the activity of superoxide dismutase (SOD) and catalase (CAT), two antioxidant enzymes; it was significantly decreased after co-exposure. We also noted an increase in the lipid oxidation product malondialdehyde (MDA) after co-exposure. Furthermore, co-exposure to NPs and TCS had a more detrimental effect on mitochondrial function than the individual treatments. Co-exposure activated the NRF2-KEAP1-HO-1 antioxidant stress pathway. Surprisingly, the expression of SESTRIN2, an antioxidant protein, was inhibited by co-exposure treatments. Co-exposure to NPs and TCS significantly increased the autophagy-related proteins LC3B-II and LC3B-Ⅰ and decreased P62. Moreover, co-exposure enhanced CASPASE-3 expression and inhibited the BCL-2/BAX ratio. In summary, our study revealed the synergistic toxic effects of NPs and TCS in vitro exposure. Our findings provide insight into the toxic mechanisms associated with co-exposure to NPs and TCS to KGN cells by inducing oxidative stress, activations of the NRF2-KEAP1-HO-1 pathway, autophagy, and apoptosis.

Discussion: Harnessing microbiome-mediated adaptations in insect pollinators to mitigate climate change impact on crop pollination

Insect pollinators, vital for agriculture and biodiversity, face escalating threats from climate change. We argue and explore the pivotal role of the microbiomes in shaping adaptations of insect pollinator resilience amid climate-induced challenges (climate change and habitat alteration). Examining diverse taxonomic groups, we unravel the interplay between insect physiology, microbiomes, and adaptive mechanisms. Climate-driven alterations in microbiomes impact insect health, behavior, and plant interactions, posing significant effects on agricultural ecosystems. We propose harnessing microbiome-mediated adaptations as a strategic approach to mitigate climate change impacts on crop pollination. Insights into insect-pollinator microbiomes offer transformative avenues for sustainable agriculture, including probiotic interventions (use of EM PROBIOTIC) and microbiome engineering (such as engineering gut bacteria) to induce immune responses and enhanced pollination services. Integrating microbiome insights into conservation practices elucidates strategies for preserving pollinator habitats, optimizing agricultural landscapes, and developing policies to safeguard pollinator health in the face of environmental changes. Finally, we stress interdisciplinary collaboration and the urgency of understanding pollinator microbiome dynamics under climate change in future research.

Investigating the ecological implications of nanomaterials: Unveiling plants' notable responses to nano-pollution

The rapid advancement of nanotechnology has led to unprecedented innovations; however, it is crucial to analyze its environmental impacts carefully. This review thoroughly examines the complex relationship between plants and nanomaterials, highlighting their significant impact on ecological sustainability and ecosystem well-being. This study investigated the response of plants to nano-pollution stress, revealing the complex regulation of defense-related genes and proteins, and highlighting the sophisticated defense mechanisms in nature. Phytohormones play a crucial role in the complex molecular communication network that regulates plant responses to exposure to nanomaterials. The interaction between plants and nano-pollution influences plants' complex defense strategies. This reveals the interconnectedness of systems of nature. Nevertheless, these findings have implications beyond the plant domain. The incorporation of hyperaccumulator plants into pollution mitigation strategies has the potential to create more environmentally sustainable urban landscapes and improve overall environmental resilience. By utilizing these exceptional plants, we can create a future in which cities serve as centers of both innovation and ecological balance. Further investigation is necessary to explore the long-term presence of nanoparticles in the environment, their ability to induce genetic changes in plants over multiple generations, and their overall impact on ecosystems. In conclusion, this review summarizes significant scientific discoveries with broad implications beyond the confines of laboratories. This highlights the importance of understanding the interactions between plants and nanomaterials within the wider scope of environmental health. By considering these insights, we initiated a path towards the responsible utilization of nanomaterials, environmentally friendly management of pollution, and interdisciplinary exploration. We have the responsibility to balance scientific advancement and environmental preservation to create a sustainable future that combines nature's wisdom with human innovation.