Every few months a headline pops up about insects eating plastic, and someone asks me if BSFL can solve the plastic crisis. The honest answer is: the research is interesting, it's real science, and it's nowhere close to a practical solution. But it's worth understanding what's actually happening, because the biology is genuinely fascinating.
What Researchers Have Found
A 2025 study published in the Journal of Applied Microbiology by Dragone et al. fed BSFL diets containing microplastics, specifically polyethylene terephthalate (PET), polylactic acid (PLA), and polyhydroxybutyrate (PHB). What they found was that the larvae didn't break down the plastics directly. Instead, their gut microbiome shifted in response to the plastic exposure, selecting for bacteria with plastic-degrading capabilities.
The researchers isolated seven bacterial strains from plastic-fed BSFL guts and confirmed those bacteria could degrade polyhydroxybutyrate in lab conditions. The idea isn't that larvae eat plastic the way they eat food scraps. It's that their gut acts as a kind of incubator for plastic-degrading bacteria, concentrating and selecting for microbes that might be useful in other applications.
Earlier Work Showed Similar Patterns
De Filippis et al. (2023) and Piersanti et al. (2024) found that plastics like polyethylene, PVC, and polystyrene showed structural changes after passing through BSFL digestive tracts. The plastics came out different than they went in. That's meaningful from a research perspective, but "structural alteration" is a long way from "complete degradation." The gut microbes are doing something, but how much and how fast is still being worked out.
There's also the question of what this does to the larvae. Some studies report negative effects on larval fitness when they're exposed to plastics. Others report no significant impact. The research isn't settled, and the practical implications for anyone actually raising BSFL are straightforward: don't feed your larvae plastic.
Why This Matters Even If It's Not a Solution Yet
The value of this research isn't in BSFL as plastic processors. It's in using BSFL as a tool for discovering and isolating bacteria that can degrade plastics. If you can identify which microbes do the work, you can potentially culture those bacteria at scale for industrial plastic remediation. The larvae are the discovery tool, not the end product.
Scaling any biological plastic degradation method to industrial relevance is a massive challenge. Plastics are chemically stable by design, that's why they last centuries in a landfill. Breaking them down biologically requires finding organisms that can do what chemistry was specifically designed to prevent. Progress is being made, but it's measured in published papers, not in tons of plastic processed.
The Bottom Line
BSFL gut microbiomes show real, documented potential for plastic degradation research. The science is legitimate and the direction is promising. But if someone tells you BSFL can solve plastic pollution, they're about a decade and several breakthroughs ahead of where the research currently stands.
What BSFL can do right now, today, is process organic waste at impressive speed and efficiency. That's the proven application. The plastic research is worth following, but it's not a reason to start a colony. Turning your food scraps into chicken feed and garden fertilizer in three weeks, that's a reason to start a colony.
Reference: Dragone, N. B., et al. (2025). Examining the potential of plastic-fed black soldier fly larvae (Hermetia illucens) as "bioincubators" of plastic-degrading bacteria. Journal of Applied Microbiology, 136(4), lxaf085.
