Co-exposure of butyl benzyl phthalate and TiO nanomaterials (anatase) in Metaphire guillelmi: Gut health implications by transcriptomics.

During the COVID-19 pandemic, an abundance of plastic face masks has been consumed and disposed of in the environment. In addition, substantial amounts of plastic mulch film have been used in intensive agriculture with low recovery. Butyl benzyl phthalate (BBP) and TiO nanomaterials (nTiO) are widely applied in plastic products, leading to the inevitable release of BBP and nTiO into the soil system. However, the impact of co-exposure of BBP and nTiO at low concentrations on earthworms remains understudied. In the present study, transcriptomics was applied to reveal the effects of individual BBP and nTiO exposures at a concentration of 1 mg kg, along with the combined exposure of BBP and nTiO (1 mg kg BBP + 1 mg kg nTiO (anatase)) on Metaphire guillelmi. The result showed that BBP and nTiO exposures have the potential to induce neurodegeneration through glutamate accumulation, tau protein, and oxidative stress in the endoplasmic reticulum and mitochondria, as well as metabolism dysfunction. The present study contributes to our understanding of the toxic mechanisms of emerging contaminants at environmentally relevant levels and prompts consideration of the management of BBP and nTiO within the soil ecosystems.