Female mosquito-a potential vector for transporting plastic residues to humans

Detection of heavy metals in various stages of development for wild mosquitoes of Aedes aegypti and Aedes albopictus sourced from artificial aquatic niches in arbovirus endemic areas

Bioaccumulation of heavy metals was observed in Aedes aegypti and Aedes albopictus mosquitoes. Both species are recognized as primary vectors of arboviruses such as dengue, chikungunya, and Zika in an endemic arbovirus region of Iguala and Tomatal, Guerrero, Mexico; where specimens were collected from contaminated artificial aquatic niches. A total of nine heavy metals, including nickel, Cadmium, copper, and lead, were detected in the artificial aquatic niches and at various stages of mosquito development (larvae, pupae, and adults). The findings indicated that nickel and cadmium are the predominant metals in these environments. Furthermore, substantial bioaccumulation of heavy metals was evident in mosquitoes throughout their life cycle, particularly in larvae and pupae, with cadmium as the most prevalent metal. Adult females of Ae. aegypti exhibited higher concentrations of heavy metals than males, suggesting potential implications for reproduction and disease transmission capacity. The investigation underscores the significance of monitoring heavy metals accumulation and pollution in these niches, as it may influence mosquito ecology and potentially enhance their resistance to insecticides and susceptibility to viral infections.

Can microplastic contamination affect the wing morphology and wingbeat frequency of Aedes aegypti (Diptera: Culicidae) mosquitoes?

Microplastics (MPs) are increasingly widespread in the environment, which raises questions about their potential effects at different biological levels. It is essential to assess the impacts on biodiversity, and it is also crucial to understand whether the presence of MPs can interfere with the biological traits of species of relevance in public health. Considering that the life-history traits of mosquitoes, such as size and the wingbeat frequency (WBF), are related to its vector competence, here, we study the effects of 106 particles L-1 (as expected concentration of MPs on the environment, using the polyethylene type) on WBF, as well as wing morphology, testing the Culicidae species found across all continents, Aedes aegypti, as an indicator. Results show that larvae survival and development were not affected by the tested concentration of MP. Geometric morphometrics showed some asymmetry in female mosquito wings, which were also smaller for individuals reared in MP suspension. As for WBF, results did not indicate any significant differences between females. Male mosquitoes, however, showed alterations in WBF and wing morphology, suggesting possible sex-specific reactions to microplastic exposure. Also, the combination of morphological parameters analyzed as covariates (wing centroid size and body weight) did not significantly affect WBF for both female and male mosquitoes. Overall, this study shows an inaugural investigation of the effects of MP on wing size and WBF on Ae. aegypti, shedding light on these parameters tested for a current pollution issue and its impact on a virus vector.

Changes in the wing shape and size in fruit flies exposed to micro and nanoplastics

Geometric morphometrics analysis (GMA) is a well-known technique to identify minute changes in Drosophila wings. This study aimed to determine potential changes in Drosophila wings shape and size after exposure to polystyrene nanoplastics (NPs) (50 nm) and microplastics (MPs) (1 μm). Flies were exposed from eggs to pupal eclosion and analyzed using GMA. Results revealed a difference in shape and size between male and female wings, as expected, due to sexual dimorphism. Therefore, wings were analyzed by sex. Wings of MPs and NPs treated females were elongated compared to controls and had a constriction of the wing joint. Additionally, MPs treated female flies had the most dissimilar shape compared to controls. In male flies, NPs flies had smaller wings compared to MPs and control flies. Compared to control, NPs wings of males were shrunken at the joint and in the entire proximal region of the wing. However, male MPs wings had a narrower anal region and were slightly elongated. These results reveal that wing shape and size can change in a different way based on the sex of the flies and size of plastic particles that larvae interacted with. All the changes in the wings occurred only within the normally allowed wing variation and treatment with NPs/MPs did not cause development of the aberrant phenotypes. Results can pave the way for further understanding of how MPs and NPs can alter phenotypes of flies.

The effects of nano- and microplastic ingestion on the survivorship and reproduction of Aedes aegypti and Aedes albopictus (Diptera: Culicidae)

Microplastics (MPs) and nanoplastics (NPs) are pervasive environmental pollutants that are commonly ingested by organisms at different trophic levels. While the effects of MPs on aquatic organisms have been extensively studied, the impacts of MP ingestion on the host fitness of terrestrial organisms, mainly insects, have been relatively unexplored. This study investigates the effects of MP and NP ingestion on the survivorship and reproduction of 2 medically important mosquito species, Aedes aegypti Linnaeus (Diptera: Culicidae) and Aedes albopictus Skuse (Diptera: Culicidae). Larval and pupal survivorship of Ae. albopictus were not significantly affected by particle size or concentration, but there was a reduction of Ae. aegypti pupal survivorship associated with the ingestion of 0.03 µm NPs. In addition, there was little observed impact of 0.03 µm NP and 1.0 µm MP ingestion on adult survivorship, fecundity, and longevity. To further investigate the effects of MP ingestion on mosquito fitness, we also examined the effects of MPs of varying shape, size, and plastic polymer type on Ae. aegypti immature and adult survivorship. The data suggest that the polymer type and shape did not impact Ae. aegypti immature or adult survivorship. These findings highlight that understanding the effects of microplastic ingestion by mosquitoes may be complicated by the size, composition, and amount ingested.

Exposure Pathways and Toxicity of Microplastics in Terrestrial Insects

The detrimental effects of plastics on aquatic organisms, including those of macroplastics, microplastics, and nanoplastics, have been well established. However, knowledge on the interaction between plastics and terrestrial insects is limited. To develop effective strategies for mitigating the impact of plastic pollution on terrestrial ecosystems, it is necessary to understand the toxicity effects and influencing factors of plastic ingestion by insects. An overview of current knowledge regarding plastic ingestion by terrestrial insects is provided in this Review, and the factors influencing this interaction are identified. The pathways through which insects interact with plastics, which can lead to plastic accumulation and microplastic transfer to higher trophic levels, are also discussed using an overview and a conceptual model. The diverse impacts of plastic exposure on insects are discussed, and the challenges in existing studies, such as a limited focus on certain plastic types, are identified. Further research on standardized methods for sampling and analysis is crucial for reliable research, and long-term monitoring is essential to assess plastic trends and ecological impacts in terrestrial ecosystems. The mechanisms underlying these effects need to be uncovered, and their potential long-term consequences for insect populations and ecosystems require evaluation.

Generation and Fate of Nanoplastics in the Intestine of Plastic-Degrading Insect (Tenebrio molitor Larvae) during Polystyrene Microplastic Biodegradation

The insect Tenebrio molitor exhibits ultrafast efficiency in biodegrading polystyrene (PS). However, the generation and fate of nanoplastics (NPs) in the intestine during plastic biodegradation remain unknown. In this study, we investigated the biodegradation of PS microplastics (MPs) mediated by T. molitor larvae over a 4-week period and confirmed biodegradation by analyzing Δδ13C in the PS before and after biotreatment (-28.37‰ versus -24.88‰) as an effective tool. The ·OH radicals, primarily contributed by gut microbiota, and H2O2, primarily produced by the host, both increased after MP digestion. The size distribution of residual MP particles in excrements fluctuated within the micrometer ranges. PS NPs were detected in the intestine but not in the excrements. At the end of Weeks 1, 2, 3, and 4, the concentrations of PS NPs in gut tissues were 3.778, 2.505, 2.087, and 2.853 ng/lava, respectively, while PS NPs in glands were quantified at 0.636, 0.284, and 0.113 ng/lava and eventually fell below the detection limit. The PS NPs in glands remained below the detection limit at the end of Weeks 5 and 6. This indicates that initially, NPs generated in the gut entered glands, then declined gradually and eventually disappeared or possibly biodegraded after Week 4, associated with the elevated plastic-degrading capacities of T. molitor larvae. Our findings unveil rapid synergistic MP biodegradation by the larval host and gut microbiota, as well as the fate of generated NPs, providing new insights into the risks and fate associated with NPs during invertebrate-mediated plastic biodegradation.

Unraveling the micro- and nanoplastic predicament: A human-centric insight

Micro- and nanoplastics are vast anthropogenic pollutants in our direct surroundings with a robust environmental stability and a potential for a long-lasting and increasing global circulation. This has raised concerns among the public and policy makers for human health upon exposure to these particles. The micro- and nanoplastic burden on humans is currently under debate, along with criticism on the experimental approaches used in hazard assessment. The present review presents an overview of the human-relevant aspects associated with the current micro-and nanoplastic burden. We focus on environmental circulation and the estimation of exposure quantities to humans, along with a state-of-the-art overview of particle accumulation in over 15 human organs and other specimen. Additionally, data regarding particle characteristics used in toxicity testing was extracted from 91 studies and discussed considering their environmental and human relevance.

Unraveling the threat: Microplastics and nano-plastics' impact on reproductive viability across ecosystems

Plastic pollution pervades both marine and terrestrial ecosystems, fragmenting over time into microplastics (MPs) and nano-plastics (NPs). These particles infiltrate organisms via ingestion, inhalation, and dermal absorption, predominantly through the trophic interactions. This review elucidated the impacts of MPs/NPs on the reproductive viability of various species. MPs/NPs lead to reduced reproduction rates, abnormal larval development and increased mortality in aquatic invertebrates. Microplastics cause hormone secretion disorders and gonadal tissue damage in fish. In addition, the fertilization rate of eggs is reduced, and the larval deformity rate and mortality rate are increased. Male mammals exposed to MPs/NPs exhibit testicular anomalies, compromised sperm health, endocrine disturbances, oxidative stress, inflammation, and granulocyte apoptosis. In female mammals, including humans, exposure culminates in ovarian and uterine deformities, endocrine imbalances, oxidative stress, inflammation, granulosa cell apoptosis, and tissue fibrogenesis. Rodent offspring exposed to MPs experience increased mortality rates, while survivors display metabolic perturbations, reproductive anomalies, and weakened immunity. These challenges are intrinsically linked to the transgenerational conveyance of MPs. The ubiquity of MPs/NPs threatens biodiversity and, crucially, jeopardizes human reproductive health. The current findings underscore the exigency for comprehensive research and proactive interventions to ameliorate the implications of these pollutants.

Interactions between microplastics and insects in terrestrial ecosystems-A systematic review and meta-analysis

The presence of microplastics (MPs) in terrestrial ecosystems has been confirmed worldwide. Due to their widespread distribution and diversity in habitats, insects will readily interact with MPs via various pathways. Although the topic of MP-insect interactions is still in the early stages of research, it is becoming increasingly important. We used a META approach with phylogenetic control and subgroup examination to summarize the evidence from both field and laboratory experiments in quantitative form. The field evidence suggests that insects can take and transfer MPs along food chains via ingestion and adherence. Also, they are active in the bio-fragmentation of MPs and the generation of secondary pollutants. The exposure to MPs impaired key biological traits of insects, mainly their behavior and health, such as reducing climbing ability and increasing oxidative stress. In terms of exposure conditions, the small-sized MPs can induce more severe effects on the insects, while the insect response to MPs was not significantly reliant on exposure times or MP concentrations based on the current evidence available. We propose that insects not only play roles in the redistribution of MPs spatially and in food chains via bio-fragmentation but are also threatened by MPs. Our research deepens our understanding of the environmental risks posed by MPs in insect ecosystems.

Microplastic ingestion perturbs the microbiome of Aedes albopictus (Diptera: Culicidae) and Aedes aegypti

Microplastics (MPs) are common environmental pollutants; however, little is known about their effects after ingestion by insects. Here we fed Aedes (Stegomyia) aegypti (L.) and Aedes (Stegomyia) albopictus (Skuse) mosquito larvae 1 µm polystyrene MPs and examined the impacts of ingestion on adult emergence rates, gut damage, and fungal and bacterial microbiota. Results show that MPs accumulate in the larval guts, resulting in gut damage. However, little impact on adult emergence rates was observed. MPs are also found in adult guts postemergence from the pupal stage, and adults expel MPs in their frass after obtaining sugar meals. Moreover, MPs effects on insect microbiomes need to be better defined. To address this knowledge gap, we investigated the relationship between MP ingestion and the microbial communities in Ae. albopictus and Ae. aegypti. The microbiota composition was altered by the ingestion of increasing concentrations of MPs. Amplicon sequence variants (ASVs) that contributed to differences in the bacterial and fungal microbiota composition between MP treatments were from the genera Elizabethkingia and Aspergillus, respectively. Furthermore, a decrease in the alpha diversity of the fungal and bacterial microbiota was observed in treatments where larvae ingested MPs. These results highlight the potential for the bacterial and fungal constituents in the mosquito microbiome to respond differently to the ingestion of MPs. Based on our findings and the effects of MP ingestion on the mosquito host micro- and mycobiome, MP pollution could impact the vector competence of important mosquito-transmitted viruses and parasites that cause human and animal diseases.

Reproductive toxicity of micro- and nanoplastics

Large-scale plastic pollution occurs in terrestrial and marine environments and degrades into microparticles (MP) and nanoparticles (NP) of plastic. Micro/nanoplastics (MP/NPs) are found throughout the environment and different kinds of marine organisms and can enter the human body through inhalation or ingestion, particularly through the food chain. MPs/NPs can enter different organisms, and affect different body systems, including the reproductive, digestive, and nervous systems via the induction of different stresses such as oxidative stress and endoplasmic reticulum stress. This paper summarizes the effects of MPs/NPs of different sizes on the reproduction of different organisms including terrestrial and marine invertebrates and vertebrates, the amplification of toxic effects between them through the food chain, the serious threat to biodiversity, and, more importantly, the imminent challenge to human reproductive health. There is a need to strengthen international communication and cooperation on the remediation of plastic pollution and the protection of biodiversity to build a sustainable association between humans and other organisms.

Multispectroscopy analysis of polystyrene nanoplastic interaction with diastase α-amylase

The digestive enzyme of plant are generally α-amylase. They functions enzyme that breakdown starch into maltose and sugars. This happens in the endosperm of the seed. Due to pollutants, this process get happened one of emergent xenobiotics are micro and nano plastics. This study involves the interaction 100 nm size of polystyrene nano plastic (PSNPs) on α-amylase. The hyperchromism of α-amylase - PSNPs conjugate's revealed that ground-state complex in a microenvironment. Fluorescence quenching happened when the concentration of PSNPs was increased. The Stern Volmer plot revealed binding constant (Ka) was 1.904 × 1019 M-1. S-1 while the quenching constant (Kq) was 1.036 × 1011 M-1, the blue shift of the peak showed static quenching. The binding constant was KA = 4.2 × 1012, the number of binding site on PSNPs for α-amylase was n = 1.12. The synchronous result showed a gradual reduction in the intensity of Trp residues because when the α-amylase interacts with PSNPs short-range π-π interaction happens around the Trp163 residues. The enzyme activity of α-amylase by 44 % and its IC50 value was found to be 100 µg/mL. The enzyme kinetics (Vmax) analysis showed the type of inhibition with and without PSNPs Vmax 769 and Vmax 303 µg/mL/min, uncompetitive inhibition respectively. The effect of PSNPs on the enzymatic activity of α-amylase showed structural alterations of the protein. Therefore the in vitro and in silico studies were shown evidence of interaction between α-amylase and PSNPs leads to conformational structural changes in α-amylase.

Plastic particles in medicine: A systematic review of exposure and effects to human health

Single-use plastics (SUPs) have become an essential constituent of our daily life. It is being exploited in numerous pharmaceutical and healthcare applications. Despite their advantages and widespread use in the pharma and medical sectors, the potential clinical problems of plastics, especially the release of micro-nanoplastics (MNPs) and additives from medical plastics (e.g. bags, containers, and administrative sets) and sorption of drugs remain understudied. Certainly, the MNPs are multifaceted stressors that cause detrimental effects to the ecosystem and human health. The origin and persistence of MNPs in pharmaceutical products, their administration to humans, endurance and possible health implication, translocation, and excretion have not been reviewed in detail. The prime focus of this article is to conduct a systematic review on the leaching of MNPs and additives from pharmaceutical containers/administrative sets and their interaction with the pharmaceutical constituents. This review also explores the primary and secondary routes of MNPs entry from healthcare plastic products and their potential health hazards to humans. Furthermore, the fate of plastic waste generated in hospitals, their disposal, and associated MNPs release to the environment, along with preventive, and alternative measures are discussed herein.