TY - JOUR

T1 - Microplastics in European sea salts – An example of exposure through consumer choice and of interstudy methodological discrepancies

AU - Thiele, Christina

AU - Grange, Laura

AU - Haggett, Emily

AU - Hudson, Malcolm

AU - Hudson, Philippa

AU - Russell, Andrea

AU - Zapata-Restrepo, Lina M.

PY - 2023/4/15

Y1 - 2023/4/15

N2 - Microplastics are contaminants of emerging concern, not least due to their global presence in marine surface waters. Unsurprisingly, microplastics have been reported in salts harvested from numerous locations. We extracted microplastics from 13 European sea salts through 30% H O digestion and filtration over 5-µm filters. Filters were visually inspected at magnifications to x100. A subsample of potential microplastics was subjected to Raman spectroscopy. Particle mass was estimated, and human dose exposure calculated. After blank corrections, median concentrations were 466 ± 152 microplastics kg ranging from 74 to 1155 items kg . Traditionally harvested salts contained fewer microplastics than most industrially harvested ones (t-test, p < 0.01). Approximately 14 µg of microplastics (< 12 particles) may be absorbed by the human body annually, of which a quarter may derive from a consumer choosing sea salt. We reviewed existing studies, showing that targeting different particle sizes and incomplete filtrations hinder interstudy comparison, indicating the importance of method harmonisation for future studies. Excess salt consumption is detrimental to human health; the hazardousness of ingesting microplastics on the other hand has yet to be shown. A portion of microplastics may enter sea salts through production processes rather than source materials. [Abstract copyright: Copyright © 2023 The Authors. Published by Elsevier Inc. All rights reserved.]

AB - Microplastics are contaminants of emerging concern, not least due to their global presence in marine surface waters. Unsurprisingly, microplastics have been reported in salts harvested from numerous locations. We extracted microplastics from 13 European sea salts through 30% H O digestion and filtration over 5-µm filters. Filters were visually inspected at magnifications to x100. A subsample of potential microplastics was subjected to Raman spectroscopy. Particle mass was estimated, and human dose exposure calculated. After blank corrections, median concentrations were 466 ± 152 microplastics kg ranging from 74 to 1155 items kg . Traditionally harvested salts contained fewer microplastics than most industrially harvested ones (t-test, p < 0.01). Approximately 14 µg of microplastics (< 12 particles) may be absorbed by the human body annually, of which a quarter may derive from a consumer choosing sea salt. We reviewed existing studies, showing that targeting different particle sizes and incomplete filtrations hinder interstudy comparison, indicating the importance of method harmonisation for future studies. Excess salt consumption is detrimental to human health; the hazardousness of ingesting microplastics on the other hand has yet to be shown. A portion of microplastics may enter sea salts through production processes rather than source materials. [Abstract copyright: Copyright © 2023 The Authors. Published by Elsevier Inc. All rights reserved.]

U2 - 10.1016/j.ecoenv.2023.114782

DO - 10.1016/j.ecoenv.2023.114782

M3 - Article

VL - 255

JO - Ecotoxicology and Environmental Safety

JF - Ecotoxicology and Environmental Safety

M1 - 114782

ER -