Table 2.

Analysis of thiacloprid residue

Time after contamination (h)	Mean measured concentrations ± standard deviation at different time-points after contamination (μg/l)
	Nominal concentration (μg/l)
	0.1	3.2	100
First-year contamination (n = 4)a
48	NM	3.55 ± 2.80	36.64 ± 10.37
120	NM	1.29 ± 1.61b	6.48 ± 1.43
264	NM	NM	5.43 ± 0.75b
Second-year contamination (n = 8)c
4	0.07 ± 0.05	2.64 ± 0.21	76.33 ± 10.03d
10	NM	NM	65.67 ± 11.91d
48	0.04 ± 0.01	0.48 ± 0.54	32.62 ± 9.88
120	0.02 ± 0.01	0.23 ± 0.20	9.23 ± 7.08
216	0.02 ± 0.02e	0.07 ± 0.05	2.52 ± 3.61
312	<0.01e	<0.01	0.36 ± 0.53
480	<0.01e	<0.01	0.08 ± 0.12
648	NM	NM	<0.01

NM not measured

^aTwo samples from each of the two channels

^b n = 2

^cTwo samples from each of the four channels

^d n = 6, two out of four streams were sampled with three samples each

^e n = 4, one sample from each of the four channels