Table 1. Recoveries from 10 μM AP Solution Containing Potentially Interferent Common Soil Ions at a 1- to 5-Fold Concentrations.

interferent ion	interferent ion final concentration (μM)	(analyte/interferent ion) mole ratio	recovery (%)	(analyte/cation–anion/EDTA) mole ratio	recovery (%)
Cl–	10	1	110
	50	5	95
NO3–	10	1	100
	50	5	100
SO42–	10	1	110
	50	5	90
CH3COO–	10	1	101
	50	5	102
HCO3–	10	1	98
	50	5	93
B4O72–	10	1	96
	50	5	90
F–	10	1	108
	50	5	96
NO2–	10	1	110	1:5:1	106
	50	5	126
K+	10	1	95
	50	5	90
NH4+	10	1	101
	50	5	109
Mg2+	10	1	93	1:5:0.25	100
	50	5	85
	100	10	106
Ca2+	10	1	90	1:5:0.25	90
	50	5	83
	100	10	102
Fe3+	10	1	105
	50	5	97
Cu2+	10	1	110
	50	5	87