Faculty of Marine Resources and Environment, Tokyo University of Marine Science and Technology, Konan 4-5-7, Minato-Ku, Tokyo 108-8477, Japan.
Faculty of Marine Resources and Environment, Tokyo University of Marine Science and Technology, Konan 4-5-7, Minato-Ku, Tokyo 108-8477, Japan.
Mar Pollut Bull. 2023 Dec;197:115700. doi: 10.1016/j.marpolbul.2023.115700. Epub 2023 Oct 31.
Carbonyl index (CI) is a measure of the degradation status of microplastics. While many studies address environmental factors of microplastic degradation, intrinsic factors like physical properties, spectral properties, baseline correction, and CI calculation methods are less explored. This research focused on these aspects using surface seawater samples. We found that color and shape have limited dependence on particle size or signal-to-noise ratio (SNR). Baseline correction can significantly alter CI values, with the direction of the shift depending on the methods used. Additionally, most CI values before and after baseline correction and those calculated using different methods tend to be strongly correlated. Using the selected CI calculation methods, we found that CI values varied significantly by shape and color. CI's relation to the similarity between the sample and its pristine form suggests an alternative degradation measure. Our findings emphasize the need for standardized CI calculation methods.
羰基指数（CI）是衡量微塑料降解状态的一个指标。虽然许多研究都涉及微塑料降解的环境因素，但物理性质、光谱性质、基线校正和 CI 计算方法等内在因素的研究却较少。本研究使用表层海水样本对此进行了探讨。我们发现，颜色和形状与粒径或信噪比（SNR）的相关性较小。基线校正会显著改变 CI 值，其偏移方向取决于所采用的方法。此外，大多数基线校正前后以及使用不同方法计算得到的 CI 值之间往往具有很强的相关性。使用选定的 CI 计算方法，我们发现 CI 值因形状和颜色的不同而有显著差异。CI 值与样品与其原始形态之间相似性的关系表明，CI 是一种替代的降解衡量指标。我们的研究结果强调了需要采用标准化的 CI 计算方法。
