. 2019 Sep 10;9:13058. doi: 10.1038/s41598-019-49087-z

Table 4.

Heavy metal concentration in recipes for dogs and comparison to maximum tolerable levels (MTL).

	Heavy metal concentration (mg/kg of DM)
	MTL	Mean ± SD	Range	% above MTL (n)	% samples with detection (n)
Aluminum (Al)	200^a	26.04 ± 25.37	<0.001–159.48	0.0 (0)	97.3 (73)
Arsenic (As)	12.5^b	0.17 ± 0.09	<0.001–0.58	0.0 (0)	18.7 (14)
Boron (B)	150^a	—	—	0.0 (0)	0.0 (0)
Barium (Ba)	100^a	4.93 ± 3.80	<0.001–15.02	0.0 (0)	97.3 (73)
Beryllium (Be)	5^b	0.43 ± 0.19	<0.001–1.52	0.0 (0)	8.0 (6)
Cadmium (Cd)	10^b	0.61 ± 0.57	<0.001–2.62	0.0 (0)	84.0 (63)
Cobalt (Co)	2.5^b	1.06 ± 0.68	<0.001–3.08	4.0 (3)	89.3 (67)
Chromium (Cr)	10^b	2.15 ± 1.11	<0.001–6.58	0.0 (0)	97.3 (73)
Mercury (Hg)	0.27^b	0.76 ± 1.07	<0.001–6.07	70.7 (53)	92.0 (69)
Nickel (Ni)	50^b	1.53 ± 2.27	<0.001–19.44	0.0 (0)	86.7 (65)
Lead (Pb)	10^b	8.28 ± 4.67	<0.001–20.07	26.7 (20)	89.3 (67)
Antimony (Sb)	40^b	1.13 ± 0.59	0.13–3.27	0.0 (0)	100.0 (75)
Tin (Sn)	100^a	6.94 ± 2.71	0.53–16.42	0.0 (0)	100.0 (75)
Uranium (U)	10^b	68.49 ± 40.57	<0.001–173.36	92.0 (69)	97.3 (73)
Vanadium (V)	1^b	1.51 ± 1.12	<0.001–5.02	53.3 (40)	84.0 (63)

MTL. maximum tolerable level; SD. standard deviation; ^areference level for most sensitive mammal according to National Research Council³⁷; ^breference level for most sensitive mammal according to United States Food and Drug Administration³⁶.