An increasing number of states and municipalities are choosing to reduce plastic litter by replacing plastic items, particularly single-use ones, with same-use products manufactured from compostable plastics. This study investigated the formation and persistence of compostable film microplastic particles (CFMPs) from ultra-thin compostable carrier bags in soil under laboratory conditions, and the potential impact of CFMPs on Aspergillus flavus populations in the soil.

During a 12-month incubation period, compostable film samples in soils with small, medium or large populations of indigenous A. flavus, underwent 5.9, 9.8, and 17.1% reduction in total surface area, respectively. Despite the low levels of deterioration, the number of CFMPs released increased steadily over the incubation period, particularly fragments with size < 0.05 mm. Up to 88.4% of the released fragments had associated A. flavus and up to 68% of isolates from CFMPs produced aflatoxins. A. flavus levels associated with CFMPs increased rapidly during the initial part of the 12-month incubation period, whereas the percent aflatoxigenicity continued to increase even after A. flavus density leveled off later. During 12 months incubation, A. flavus DNA amounts recovered from CFMPs increased in soils with all levels of indigenous A. flavus, with the largest increases (119.1%) occurring in soil containing the lowest indigenous A. flavus. These results suggest that burying compostable film in soil, or application of compost containing CFMPs, may reduce soil quality and increase risk of adverse impacts from elevated aflatoxigenic A. flavus populations in soil.

越来越多的州和市政当局正在选择通过用可堆肥塑料制造的相同用途产品代替塑料物品（尤其是一次性物品）来减少塑料垃圾。这项研究调查了在实验室条件下土壤中超薄可堆肥载体袋中可堆肥薄膜微塑料颗粒（CFMP）的形成和持久性，以及CFMP对土壤中黄曲霉种群的潜在影响。

在为期12个月的孵育期间，在具有少量，中等或大量原生黄曲霉菌的土壤中，可堆肥薄膜样品的总表面积分别减少了5.9％，9.8％和17.1％。尽管降解程度很低，但在孵育期间释放的CFMP数量稳步增加，尤其是大小<0.05 mm的片段。高达88.4％的释放片段具有相关的黄曲霉，并且高达68％的CFMP分离物产生了黄曲霉毒素。在12个月的培养初期，与CFMP相关的黄曲霉菌水平迅速增加，而即使在黄曲霉菌发生后，黄曲霉菌性百分比仍继续增加稍后密度趋于平稳。在培养的12个月中，从所有水平的土著黄曲霉中提取的CFMP中的黄曲霉DNA量均增加，其中最大的增长（119.1％）发生在含有最低土著黄曲霉的土壤中。这些结果表明，将可堆肥膜埋在土壤中或使用含CFMPs的堆肥可能会降低土壤质量，并增加土壤中黄曲霉菌黄曲霉菌种群的增加而产生不利影响的风险。