Department of Agricultural Sciences, University of Naples Federico II, via Università 100, 80055, Portici, Italy; Task Force on Microbiome Studies, University of Naples Federico II, Naples, Italy.
Department of Biology, University of Naples Federico II, Complesso Universitario di Monte S. Angelo, via Cinthia ed. 7, 80126, Naples, Italy.
Environ Pollut. 2020 Jun;261:114108. doi: 10.1016/j.envpol.2020.114108. Epub 2020 Jan 31.
Cigarette butts (CBs) are the most common litter item on Earth but no long-term studies evaluate their fate and ecological effects. Here, the role of nitrogen (N) availability and microbiome composition on CBs decomposition were investigated by a 5-years experiment carried out without soil, in park grassland and sand dune. During decomposition, CBs chemical changes was assessed by both C CPMAS NMR and LC-MS, physical structure by scanning electron microscope and ecotoxicity by Aliivibrio fischeri and Raphidocelis subcapitata. Microbiota was investigated by high-throughput sequencing of bacterial and eukaryotic rRNA gene markers. CBs followed a three-step decomposition process: at the early stage (∼30 days) CBs lost ∼15.2% of their mass. During the subsequent two years CBs decomposed very slowly, taking thereafter different trajectories depending on N availability and microbiome composition. Without soil CBs showed minor chemical and morphological changes. Over grassland soil a consistent N transfer occurs that, after de-acetylation, promote CBs transformation into an amorphous material rich in aliphatic compounds. In sand dune we found a rich fungal microbiota able to decompose CBs, even before the occurrence of de-acetylation. CBs ecotoxicity was highest immediately after smoking. However, for R. subcapitata toxicity remained high after two and five years of decomposition.
烟头（CBs）是地球上最常见的垃圾，但没有长期研究评估它们的命运和生态影响。在这里，通过在公园草地和沙丘上进行为期 5 年的无土壤实验，研究了氮（N）供应和微生物群落组成对 CBs 分解的作用。在分解过程中，通过 C CPMAS NMR 和 LC-MS 评估 CBs 的化学变化，通过扫描电子显微镜评估物理结构，通过发光细菌和斜生栅藻评估生态毒性。通过细菌和真核 rRNA 基因标记的高通量测序研究了微生物组。CBs 遵循三步分解过程：在早期（约 30 天），CBs 损失了约 15.2%的质量。在随后的两年中，CBs 分解非常缓慢，此后根据 N 供应和微生物群落组成呈现不同的轨迹。在没有土壤的情况下，CBs 仅发生微小的化学和形态变化。在草地土壤上，持续发生 N 转移，在去乙酰化后，促进 CBs 转化为富含脂肪族化合物的无定形物质。在沙丘上，我们发现了丰富的真菌微生物群，它们能够在去乙酰化发生之前分解 CBs。CBs 的生态毒性在吸烟后立即最高。然而，对于斜生栅藻，在分解两年和五年后，毒性仍然很高。
