文章导读

自20世纪70年代以来，海洋中的塑料碎片一直被认为是一大环境隐患。由于人类活动的影响，塑料会在其价值链的任意一点流失到环境中，还会经历不同的运输和转化过程。为有效减少塑料对海洋生态环境的影响，首先应该确定那些因人类活动而进入环境中的塑料总量。因此，本文从聚合物类型及其应用、地理区域和塑料的生命周期等角度全面的评估了环境中塑料的损失量。原文摘要海洋中的塑料污染问题备受关注，因此迫切需要量化世界上塑料的环境损失，包括不同地理区域，不同聚合物类型，以及沿塑料价值链产生的损失。在这项研究中，我们使用现有文献和数据库以及经改进的量化损失方法模型，对全球整个塑料价值链中塑料的环境损失进行了估算，还进行了综合的敏感性和不确定性分析，以确定塑料在环境损失方面的关键因素。总体上，我们发现，2015年大约有6.2 Mt（95％置信区间，CI：2.0-20.4 Mt）的大塑料和3.0 Mt（CI：1.5-5.2 Mt）的微塑料损失到环境中。大塑料主要来源于中低收入国家（4.1 Mt）城市垃圾管理不善。对于微塑料，主要来源是橡胶轮胎的磨损，道路标记的磨损以及城市扬尘中的塑料。为了遏制海洋塑料污染，需要像我们这样的量化以评估塑料在不同来源和位置对环境造成的损失的程度，并能够进一步评估其对环境的破坏。通过不确定性和敏感性分析，我们重点介绍了在进一步研究工作中应该优先考虑的塑料来源，以便更全面、准确地表示全球塑料损失。

图1 全球塑料价值链和2015年塑料在环境中的损失估计量

图2 不同区域和来源的大塑料和微塑料的损失量

图3 不同聚合物类型和应用的大塑料和微塑料的损失量

图4 塑料损失的概率分布

图5 对塑料损失量最敏感的十个参数

原文信息

AbstractWith the increasing focus on marine plastic pollution, quantification of the environmental losses of plastics in the world, with differentiation into geographic regions, polymers and loss occurrences along the plastics value chains, is required. In this study, we make a global estimation of the losses of plastics to the environment across the entire plastic value chain, using existing literature and databases coupled with improved and additional methodological modelling of the losses. The resulting loss estimates are unprecedented in their detailed differentiations between polymers (23), plastic applications (13), geographical regions (11), and plastic value chain stages. Comprehensive sensitivity and uncertainty analyses were also conducted to identify key drivers in terms of plastic losses. We overall found that approximately 6.2 Mt (95% confidence interval, CI: 2.0–20.4 Mt) of macroplastics and 3.0 Mt (CI: 1.5–5.2 Mt) of microplastics were lost to the environment in 2015. The major macroplastic loss source was identified as the mismanaged municipal solid waste (MSW) management in low-income and lower-middle income countries (4.1 Mt). For microplastics, the major sources were abrasion of tyre rubbers, abrasion of road markings and plastics contributing to city dust generation. To curb marine plastic pollution, such quantified mapping as ours are needed to evaluate the magnitude of the plastics losses to environment from different sources and locations, and enable a further assessment of their environmental damage. Through our uncertainty and sensitivity analyses, we highlight plastics sources that should be prioritized in further research works to obtain a more comprehensive and accurate representation of global plastics losses.

本期编辑：刘盈，北京林业大学环境科学与工程学院，硕士研究生，研究方向：产业生态学