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. 2017 Apr 6;7:46173.
doi: 10.1038/srep46173.

The Presence of Microplastics in Commercial Salts From Different Countries

Free PMC article

The Presence of Microplastics in Commercial Salts From Different Countries

Ali Karami et al. Sci Rep. .
Free PMC article

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The occurrence of microplastics (MPs) in saltwater bodies is relatively well studied, but nothing is known about their presence in most of the commercial salts that are widely consumed by humans across the globe. Here, we extracted MP-like particles larger than 149 μm from 17 salt brands originating from 8 different countries followed by the identification of their polymer composition using micro-Raman spectroscopy. Microplastics were absent in one brand while others contained between 1 to 10 MPs/Kg of salt. Out of the 72 extracted particles, 41.6% were plastic polymers, 23.6% were pigments, 5.50% were amorphous carbon, and 29.1% remained unidentified. The particle size (mean ± SD) was 515 ± 171 μm. The most common plastic polymers were polypropylene (40.0%) and polyethylene (33.3%). Fragments were the primary form of MPs (63.8%) followed by filaments (25.6%) and films (10.6%). According to our results, the low level of anthropogenic particles intake from the salts (maximum 37 particles per individual per annum) warrants negligible health impacts. However, to better understand the health risks associated with salt consumption, further development in extraction protocols are needed to isolate anthropogenic particles smaller than 149 μm.

Conflict of interest statement

The authors declare no competing financial interests.


Figure 1
Figure 1. Histogram of the number of isolated particles across different sizes.
Figure 2
Figure 2. Chemical composition of the isolated particles.
(a) Pie chart of the chemical composition of the isolated particles from all salt samples and the corresponding proportion of different (b) plastic polymers and (c) pigments.
Figure 3
Figure 3. Stacked bar charts of the isolated particles across the salt brands.
Stacked bar chart of the number of (a) plastic polymer and (b) pigment particles isolated from different salt brands.
Figure 4
Figure 4. Pie chart of microplastic type.
Figure 5
Figure 5. Microscopic images of some of the extracted particles.
A (a) polyisoprene/polystyrene, (b) polyethylene, and (c) pigment (phthalocyanine) fragment. Image d is a nylon-6 filament.
Figure 6
Figure 6. Flow diagram of the developed microplastic extraction protocol from salt samples.

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    1. PlasticsEurope. Plastics e the Facts 2015. An Analysis of European Latest Plastics Production, Demand and Waste Data. (Association of Plastics Manufacturers, 2015).
    1. Jambeck J. R. et al. . Plastic waste inputs from land into the ocean. Science 347, 768–771 (2015). - PubMed
    1. Karami A. et al. . A high-performance protocol for extraction of microplastics in fish. Sci Total Environ 578, 485–494 (2017). - PubMed
    1. Karami A., Romano N., Galloway T. & Hamzah H. Virgin microplastics cause toxicity and modulate the impacts of phenanthrene on biomarker responses in African catfish (Clarias gariepinus). Environ Res 151, 58–70 (2016). - PubMed
    1. Reddy M. S., Basha S., Adimurthy S. & Ramachandraiah G. Description of the small plastics fragments in marine sediments along the Alang-Sosiya ship-breaking yard, India. Estuar Coast Shelf Sci 68, 656–660 (2006).