Feeding ability of Tenebrio molitor larvae on four common plastics

The "white pollution" caused by discarded plastics poses a serious threat on the environment, and the discovery of insects feeding on plastics provides a possibility to solve the problem of plastic pollution. This study evaluated the feeding ability of Tenebrio molitor larvae on four common plastics, such as polystyrene (disposable foam lunch boxes), polystyrene (foam boards), polypropylene (disposable plastic lunch boxes) and polyethylene (plastic bags), so as to clarify the feasibility of T. molitor larvae degrading plastics by feeding. Results indicated that when only plastic was fed, T. molitor larvae ate the most polystyrene (disposable foam lunch box), with an average feeding amount of 465 μg per larva within 7 days; followed by polystyrene (foam plates), polyethylene and polypropylene, and the average feeding amount of per larva within 7 days was 407 μg, 153.3 μg and 49.6 μg, respectively. When wheat bran exists, T. molitor larvae could also feed on plastics. Within 14 days, the average intake of polystyrene (disposable foam lunch box) and polystyrene (foam plates) fed by each larva was 317.1 μg and 337.6 μg, respectively. Moreover, adding wheat bran could significantly improve the survival rate of T. molitor larvae. The survival rate of T. molitor larvae in the wheat bran + polystyrene treatment group within 14 days (91%) was significantly higher than that of T. molitor larvae only fed on polystyrene (77%). Therefore, using T. molitor feeding on polystyrene has certain application prospects, and even the wheat bran exists, T. molitor lavea can still feed on polystyrene.