Table 1. Results of the Siphon Sampling and the Microplastics Quantification.

							Counted microplastics (np)		No. of plastics per standard sample volume (Cp)
Sample	Flume-tank floor [deg]	Sampling location	Height above the bed [cm]	Sample vol [ml]	Sediment conc (C) [%Vol]	Sediment wt (w) [g]	Melamine fragments	Polyester fibers	Melamine fragments	Polyester fibers
1	8	Mixture		27.9	15.0	11.1	194	97	6.95	3.40
2	8	Mixture		26.9	15.0	10.7	178	95	6.61	3.83
3	8	Siphon	8	555.7	0.7	10.5	48	94	0.09	0.17
4	8	Siphon	4	91.5	4.2	10.3	119	58	1.30	0.63
5	8	Siphon	2	36.4	11.8	11.4	119	35	3.26	0.96
6	8	Siphon	1	19.3	20.3	10.4	130	29	6.73	1.50
7	4	Mixture		28.2	15.0	11.2	204	103	7.24	3.44
8	4	Deposits	–1	6.5	60.0	10.4	28	43	4.28	6.57
9	4	Deposits	–2	6.5	60.0	10.4	19	29	2.90	4.43
10	4	Deposits	–3	6.5	60.0	10.3	17	35	2.62	5.40