Table 1.
Microplastic abundance (Particles kg−1) (Mean value ± SD) by shape, color, size range and, polymer categories in unpacked coarse salt samples from stations S1 to S8 (n = 3).
| S1 | S2 | S3 | S4 | S5 | S6 | S7 | S8 | |
|---|---|---|---|---|---|---|---|---|
| Shape | ||||||||
| Pellet | 6.3 ± 2.1 | 8.7 ± 3.5 | 10.7 ± 2.3 | 8.0 ± 2.0 | 7.0 ± 3.0 | 12.7 ± 4.0 | 8.7 ± 2.1 | 9.3 ± 6.4 |
| Fiber | 5.3 ± 1.5 | 8.7 ± 3.0 | 14.0 ± 4.6 | 18.3 ± 3.0 | 12.3 ± 3.5 | 18.0 ± 3.6 | 26.3 ± 5.0 | 19.7 ± 5.7 |
| Fragment | 37.7 ± 3.5 | 43.7 ± 9.1 | 27.0 ± 9.2 | 42.7 ± 10.5 | 32.7 ± 4.7 | 51.3 ± 13.6 | 59.3 ± 16.9 | 65.3 ± 7.5 |
| Film | 20.3 ± 6.1 | 13.7 ± 6.6 | 15.7 ± 5.5 | 22.7 ± 5.7 | 39.3 ± 7.5 | 22.0 ± 3.6 | 30.3 ± 5.5 | 17.7 ± 6.1 |
| Line | 7.3 ± 3.5 | 4.0 ± 2.0 | 7.3 ± 1.5 | 11.0 ± 2.0 | 17.0 ± 5.3 | 5.7 ± 2.5 | 12.0 ± 5.0 | 7.0 ± 2.6 |
| Color | ||||||||
| White | 8.0 ± 3.6 | 10.3 ± 2.5 | 7.3 ± 3.1 | 10.7 ± 1.5 | 9.7 ± 2.1 | 11.3 ± 5.0 | 19.7 ± 4.2 | 14.0 ± 5.3 |
| Blue | 2.3 ± 0.6 | 3.0 ± 1.0 | 6.3 ± 1.5 | 5.3 ± 2.5 | 4.0 ± 2.0 | 6.3 ± 1.5 | 5.7 ± 1.5 | 4.3 ± 2.5 |
| Green | 3.3 ± 0.6 | 1.7 ± 0.6 | 2.3 ± 2.1 | 3.0 ± 2.6 | 3.3 ± 1.5 | 5.3 ± 4.2 | 3.7 ± 2.5 | 2.7 ± 1.2 |
| Black | 4.3 ± 1.5 | 4.3 ± 1.5 | 3.0 ± 1.7 | 5.0 ± 2.6 | 5.7 ± 3.1 | 3.0 ± 2.0 | 7.0 ± 5.2 | 9.0 ± 3.6 |
| Pink | 1.7 ± 0.6 | 1.0 ± 1.0 | 0.7 ± 0.6 | 4.0 ± 1.0 | 2.7 ± 1.5 | 2.0 ± 1.0 | 1.3 ± 0.6 | 1.0 ± 1.0 |
| Transparent | 2.3 ± 0.6 | 2.7 ± 0.1 | 2.3 ± 0.6 | 1.7 ± 1.5 | 3.7 ± 3.1 | 3.0 ± 1.0 | 3.3 ± 1.5 | 4.7 ± 2.1 |
| Colorless | 1.3 ± 0.6 | 2.0 ± 1.0 | 0.7 ± 0.6 | 1.0 ± 1.0 | 2.7 ± 0.6 | 3.7 ± 1.5 | 1.0 ± 1.0 | 1.7 ± 0.6 |
| Size range (μm) | ||||||||
| 250–500 | 6.0 ± 3.0 | 7.0 ± 2.6 | 6.3 ± 3.1 | 8.7 ± 4.7 | 6.7 ± 4.2 | 9.0 ± 2.6 | 10.7 ± 4.0 | 9.0 ± 2.6 |
| 1000–500 | 9.7 ± 2.5 | 10.3 ± 4.2 | 7.0 ± 2.6 | 12.3 ± 2.1 | 13.0 ± 4.0 | 13.7 ± 4.2 | 17.3 ± 5.5 | 15.3 ± 2.5 |
| 1000–5000 | 7.7 ± 3.1 | 7.7 ± 2.5 | 9.3 ± 3.1 | 9.7 ± 2.1 | 11.0 ± 7.2 | 12.0 ± 3.0 | 13.7 ± 5.7 | 13.0 ± 5.3 |
| Polymer type | ||||||||
| PP | 7.0 ± 4.4 | 5.3 ± 2.08 | 5.3 ± 2.1 | 6.3 ± 1.5 | 7.7 ± 3.2 | 7.0 ± 4.0 | 9.3 ± 3.1 | 7.0 ± 2.0 |
| PET | 10.7 ± 4.2 | 11.7 ± 3.1 | 10.0 ± 6.2 | 15.3 ± 4.2 | 17.3 ± 4.9 | 19.3 ± 7.8 | 22.0 ± 6.6 | 21.7 ± 9.1 |
| PS | 4.7 ± 1.5 | 4.3 ± 1.5 | 5.0 ± 4.6 | 5.0 ± 2.0 | 5.0 ± 4.4 | 5.7 ± 3.1 | 5.7 ± 3.8 | 5.0 ± 1.7 |
| PE | 3.7 ± 2.1 | 5.0 ± 1.0 | 4.7 ± 1.5 | 7.3 ± 4.2 | 6.3 ± 6.7 | 4.3 ± 2.1 | 8.7 ± 3.1 | 6.0 ± 1.0 |
| Total | 77.0 ± 11.1 | 78.7 ± 11.0 | 74.7 ± 11.9 | 102.7 ± 11.4 | 108.3 ± 14.6 | 109.7 ± 17.9 | 136.7 ± 23.5 | 119.0 ± 22.6 |