An optimized procedure for extraction and identification of microplastics in marine sediment

Yandong Liu; Fenglei Gao; Zhaozhao Li; Huiping Ding; Dahai Zhang; Lijuan Feng; Xianguo Li

doi:10.1016/j.marpolbul.2021.112130

An optimized procedure for extraction and identification of microplastics in marine sediment

Mar Pollut Bull. 2021 Apr:165:112130. doi: 10.1016/j.marpolbul.2021.112130. Epub 2021 Feb 11.

Authors

Yandong Liu¹, Fenglei Gao², Zhaozhao Li¹, Huiping Ding¹, Dahai Zhang³, Lijuan Feng¹, Xianguo Li⁴

Affiliations

¹ Key Laboratory of Marine Chemistry Theory and Technology (Ocean University of China), Ministry of Education, Qingdao 266100, China.
² Key Laboratory of Marine Chemistry Theory and Technology (Ocean University of China), Ministry of Education, Qingdao 266100, China; Marine Bioresource and Environment Research Center, Key Laboratory of Marine Ecological Environment Science and Technology, First Institute of Oceanography, Ministry of Natural Resources, Qingdao 266061, China.
³ Key Laboratory of Marine Chemistry Theory and Technology (Ocean University of China), Ministry of Education, Qingdao 266100, China. Electronic address: dahaizhang@ouc.edu.cn.
⁴ Key Laboratory of Marine Chemistry Theory and Technology (Ocean University of China), Ministry of Education, Qingdao 266100, China. Electronic address: lixg@ouc.edu.cn.

PMID: 33582421
DOI: 10.1016/j.marpolbul.2021.112130

Abstract

Microplastics (MPs) in sediment environments have been widely reported. As the number of samples increases, establishing a reliable and effective method becomes increasingly urgent for the rapid extraction and identification of MPs in sediments. Herein, we proposed a system with continuous density flotation of NaBr-ZnCl₂ (mixture of NaBr and ZnCl₂) solution for extracting MPs in a sediment sample, combined with micro-Fourier transform infrared (μ-FT-IR) imaging scanning for identification of MPs. The recoveries of MPs were estimated for four different sizes, shapes, and ten different types of polymers. The results indicated NaBr-ZnCl₂ solution showed a high recovery rate from 88.33% to 100.00% for extracting these different MPs. The μ-FT-IR imaging scanning allows for the detection of plastic down to the size of 6.25 μm in filed samples, and merely takes about 3 min, which was validated by testing of sediments from Jiaozhou Bay, China and its adjacent estuaries.

Keywords: Extraction; Jiaozhou Bay; Microplastics; Sediment; μ-FT-IR imaging scanning.

MeSH terms

China
Environmental Monitoring
Geologic Sediments
Microplastics*
Plastics
Spectroscopy, Fourier Transform Infrared
Water Pollutants, Chemical* / analysis

Substances

Microplastics
Plastics
Water Pollutants, Chemical