Table 5. Metals tests of dry plant tissue.

Element	5001	5002a	5002b	5003	5004-1	5004-2	5005	5006	5007	5009-1	5009-2
As	1.71	1.69	1.66	1.68	1.52	1.61	1.66	1.62	1.69	1.59	1.57
Cd	0.709	0.859	<0.383	<0.391	0.506	0.500	5.38	<0.383	<0.400	<0.392	<0.399
Cr	<0.787	<0.767	<0.767	<0.781	<0.767	<0.769	<0.781	<0.766	<0.797	<0.784	<0.799
Cu	13.9	13.6	7.97	7.87	8.87	9.04	17.5	4.79	8.51	5.27	5.07
Pb	<3.94	<3.83	<3.83	<3.91	<3.83	<3.85	<3.91	<3.83	<3.99	<3.92	<3.99
Hg	<0.0393	<0.0383	<0.0383	<0.0390	<0.0383	<0.0384	<0.0390	<0.0382	<0.0398	<0.0391	<0.0399
Mo	<3.94	<3.83	<3.83	<3.91	<3.83	<3.85	<3.91	<3.83	<3.99	<3.92	<3.99
Ni	<0.787	<0.767	<0.767	<0.781	<0.767	<0.769	<0.781	<0.766	<0.797	<0.784	<0.799
Se	<2.36	<2.30	<2.30	<2.34	<2.30	<2.31	<2.34	<2.30	<2.39	<2.35	<2.40
Zn	161.0	69.6	71.8	110.6	183.1	183.5	398.2	115.2	70.9	30.7	30.5
DWT%	24.3	13.9	12.8	12.6	19.6	19.6	12.6	15.1	12.7	19.3	19.3

Results are in mg/kg (i.e., parts per million by mass). Tests were performed by Brookside Laboratories, Inc., New Bremen, OH. The concentration of lead (Pb) was below quantification limits in all samples. The repeated measurements differ by far more than the reported precision of the measurements, but with the exception of Cu, the measurements seem to be repeatable to two or three digits. Samples 5004-1 and 5004-2 are repeated tests on sample 5004; 5009-01 and 5009-02 were repeated tests on sample 5009. The bottom row, DWT%, gives the dry weight percentage for each sample. For instance, sample 5005 (a wild lettuce) weighed 36g before drying and 4.537g dry; the dry weight percentage is 100 × 4.537/36 = 12.6%. The original concentration of Cd in the wet tissue of 5005 is thus estimated to be 5.383 × 0.126 = 0.678ppm. See Table 4 for more information about the samples.