Results of CN⁻ readings in water samples from the environment.

Sample	Spiked (μM)	Found (Xa ± SDb) (μM)	Recovery (%)	RSDc (%)
Tap water	2.0	1.992 ± 0.007	99.6	0.18
	4.0	3.998 ± 0.007	99.9	0.22
	6.0	6.009 ± 0.003	100.2	0.36
Distilled water	2.0	2.003 ± 0.002	100.2	0.34
	4.0	3.992 ± 0.007	99.8	0.44
	6.0	6.011 ± 0.008	100.2	0.62
Pond water	2.0	1.948 ± 0.004	97.4	0.60
	4.0	3.921 ± 0.006	98.0	0.51
	6.0	5.933 ± 0.005	98.9	0.78

^aMean of three determinations.

^bSD: standard deviation.

^cRSD: relative standard deviation.