Microplastic Polystyrene Ingestion Promotes the Susceptibility of Honeybee to Viral Infection

Abstract

Microplastics (MPs) are an emerging threat to ecological conservation and biodiversity; however, little is known of the types and possible impacts of MPs in pollinators. To examine whether MPs were present in honeybees, we analyzed the honeybee samples collected in fields from six provinces in China. Four types MPs were identified in honeybee including polystyrene (PS) by Raman spectroscopic analysis, and these plastic polymers were detected in 66.7% bee samples. Then, we assessed the physical and biological impacts of PS of three sizes (0.5, 5, and 50 μm) on bees for 21 days. Next, we measured how the presence of PS affected the Israeli acute paralysis virus proliferation, a small RNA virus associated with bee colony decline. Experimental evidence showed that a large mass of PS was ingested and accumulated within the midgut and enhanced the susceptibility of bees to viral infection. Not only histological analysis showed that PS, especially 0.5 μm PS, damaged the midgut tissue and was subsequently transferred to the hemolymph, trachea, and Malpighian tubules, but also qPCR and transcriptomic results indicated that genes correlated with membrane lipid metabolism, immune response, detoxification, and the respiratory system were significantly regulated after PS ingestion. Our results highlight neglected MP contamination to the bees, a pollination ecosystem stressed by the anthropogenic pollution, and have implications for human health via ingestion of bee products.

Polystyrene Microplastic Beads Caused Cellular Alterations in midgut cells and Sex-Specific Toxic Effects on Survival, Starvation Resistance, and Excretion of the Model Insect Drosophila melanogaster

“…We found uorescent PS beads in the gut tissues, Malpighian tubules, hemolymph, body cavity of adult D. melanogaster ies. Our ndings support earlier studies that showed PS-MPs could be ingested and accumulated in the midgut and hind gut of honeybees as well as transported to the trachea and Malpighian tubules 52,53 . Ingested microscopic plastic also have been shown to translocate to the circulatory system of the mussel, Mytilus edulis (L.) 54 and recently have been detected in human blood and human placenta 55,56 .…”

“…Between columnar cells and inside the nucleus, intracellular clefts were seen, along with vacuolated cellular membrane, aberrant basement membrane folding, indentation in the nuclear membrane, matrix lysis, and rupture of mitochondrial cristae. Previous research has found comparable effects in bees that have been chronically exposed to PS-MPs 53 . The blue mussel (Mytilus edulis L.) also underwent considerable histological alterations after ingesting high-density polyethylene (HDPE) particles 59 .…”

Microplastics interact with SARS-CoV-2 and facilitate host cell infection

“…47 Interestingly, MP ingestion was reported to promote the susceptibility of honeybees to viral infection. 48 Since many different microorganisms are present in the human gut, their interaction with ingested MP may lead to acquisition of new properties detrimental for human health. It has been reported that SARS-CoV-2 can be found in the intestinal tract of infected people, 18 and that the virus can attach to plastic surfaces and survive there for at least 72 h. 28 There is also evidence in the mouse that inhaled MP could translocate to the brain, 49 which is another site where they can interact with SARS-CoV-2.…”

Combined transcriptome and metabolite profiling analyses provide insights into the chronic toxicity of carbaryl and acetamiprid to Apis mellifera larvae

“…Several studies have demonstrated that chronic oral exposure of larvae to insecticides significantly reduced larval survival, developmental rate and larval weight 17 – 19 . Particularly, synergistic effects may occur when pesticide exposure interact with pathogens or parasites of A. mellifera 20 – 22 . For instance, the combination of sublethal doses of thiacloprid and black queen cell virus (BQCV) significantly aggravated the proliferation of virus on host larval and potentially enhance the deleterious effects of the virus on honey bees 20 .…”