A Comparative Study of Effects of Biodegradable and Non-biodegradable Microplastics on the Growth and Development of Black Soldier Fly Larvae (Hermetia illucens)

Waste Biomass Valorization. 2024;15(4):2313-2322. doi: 10.1007/s12649-023-02296-0. Epub 2023 Oct 21.

Abstract

Purpose: This study aimed to investigate the digestion process of biodegradable and non-biodegradable microplastics (MPs) within black soldier fly larvae (BSFL) and assess their impact on larval growth and development. The goal was to understand the fate of MPs within BSFL, considering their potential for waste conversion polluted with MPs.

Methods: BSFL were exposed to two types of MPs, and their growth, development, potential accumulation and excretion of MPs were monitored.

Results: The findings revealed that the MPs accumulated solely in the larval gut and had no adverse effects on the growth and development of BSFL. Larvae efficiently excreted MPs before reaching the pupation stage.

Conclusion: This research emphasizes the potential of BSFL as a bioconversion agent for organic waste, even in the presence of MPs. The effective excretion of MPs by BSFL before pupation suggests their ability to mitigate potential harm caused by MP accumulation. The fact that BSFL may excrete MPs before pupation would contribute to their safe use as animal feedstock. A careful evaluation of the effects of using BSFL reared on contaminated substrates especially containing visually non-detectable residuals like nanoplastics, chemicals or toxic metals and further examination of the broader implications for waste management and sustainable livestock farming remains important.

Graphical abstract: Experimental design outlining the workflow for the analyses used to investigate the effect of two types of microplastics, polyamide (PA), and polylactic acid (PLA), on growth and development of black soldier fly larvae.

Keywords: Circular economy; Histology; Insect frass; Insect-based bioconversion; Microplastic mismanagement; Organic fertilizer.