A new method for detecting micro-fragments of biodegradable mulch films containing poly(butylene adipate-co-terephthalate) (PBAT) in soil.

Biodegradable mulch (BDM) is a potentially sustainable alternative to polyethylene plastic mulch film for intensive crop production. Certified BDMs must demonstrate >90% biodegradation in compost and agricultural soil, but the environmental fate of BDM micro-fragments is usually not measured. While using fatty acid methyl ester (FAME) analysis to study changes in soil microbial communities under different BDMs and management conditions, two peaks were detected by gas chromatography that were derived from a BDM containing poly(butylene adipate-co-terephthalate) (PBAT). The largest peak was identified as 1,4-benzenedicarboxylic acid, dimethyl ester, or dimethyl terephthalate (DMT). The smaller peak was hexanedioic acid dimethyl ester, or dimethyl adipate (DMA). From this observation we hypothesized that the FAME method could be used to detect and quantify micro-fragments ( 0.99). Based on our findings, the FAME method could be redeployed to study the environmental fate and possible accumulation of BDM micro-fragments in soil over time. This article is protected by copyright. All rights reserved.