Table 1.

Average recovery rates ($\overline{\mathrm{R}}\%$) and relative standard deviation (RSD) of 4 IPR laboratory tests for pesticides and PCBs. (“L” means ¹³C₁₂-labeled).

	Laboratory Test Results		EPA 1699 Accepted Range
	$\mathbf{IPR}\overline{\mathbf{R}}\mathbf{\%}$	IPR RSD	$\mathbf{IPR}\overline{\mathbf{R}}\mathbf{\%}$	IPR RSD
α-HCH	87	8	55–108	30
γ-HCH	72	4	55–108	30
HCB	103	3	55–108	30
p,p′,-DDE	81	1	55–108	30
o,p′-DDT	90	8	55–108	30
D6-α-HCH	94	4	6–112	62
13C6-γ-HCH	98	5	6–112	62
13C12-p,p′-DDE	75	17	29–152	43
13C6-HCB	87	4	6–108	70
81L	78	15	57–100	33
77L	74	12	57–100	35
123L	84	6	66–103	32
118L	96	4	65–102	33
114L	86	5	57–100	41
105L	90	4	66–101	31
126L	83	5	67–100	29
167L	86	2	74–103	24
156L	92	2	61–100	35
157L	93	5	61–100	35
169L	95	4	66–103	33
189L	99	3	68–100	28