Can Mealworms Eat Styrofoam?
Yes — but the real-world significance remains fiercely debated. The science is real. The scalability problem is enormous. And a 2025 challenge paper has reignited the argument over whether true biodegradation is occurring at all.
The Stanford Discovery
Wei-Min Wu and Craig Criddle at Stanford University published the foundational discovery in two companion papers in Environmental Science & Technology in September 2015. They showed that 100 mealworms (Tenebrio molitor larvae) consumed 34–39 mg of Styrofoam per day.
Within a 16-day test period, 47.7% of ingested carbon was converted to CO₂ and approximately 49.2% was excreted as biodegraded fragments. A companion paper identified the gut bacterium Exiguobacterium sp. strain YT2 as essential to the process — when antibiotics suppressed gut microbes, PS degradation ceased.
Superworms
A 2022 study from the University of Queensland (Rinke et al., Microbial Genomics) found that superworms (Zophobas morio) also degrade PS, identifying Pseudomonas, Rhodococcus, and Corynebacterium as genera with PS degradation genes. Superworms fed exclusively on PS for three weeks showed greater than 95% survival and marginal weight gains.
The 2025 Challenge
Tahroudi et al. (Australia) argued in 2025 that EPS undergoes only mechanical fragmentation in mealworm guts, not genuine biochemical degradation. Wu and Criddle published a rebuttal citing methodological limitations in the challenge study. This remains an active scientific debate.
The Scale Problem
The scalability problem is stark. Treating one ton of PS would require over 60 million mealworms, producing more than 4 tons of dead biomass. No company has scaled insect-based PS degradation commercially.
The field's real promise lies in isolating and engineering the responsible enzymes — particularly serine hydrolase from Pseudomonas sp. — for industrial bioreactors. No engineered enzyme analogous to PETase yet exists for PS. The fundamental challenge is that PS has a carbon-carbon backbone resistant to enzymatic cleavage, unlike PET's hydrolysable ester bonds.