Table 3.

Serum concentrations of essential trace and toxic elements (expressed in µg L⁻¹ and arithmetic mean values) in observational studies in dogs.

Type Study/Country	N	Element													References [16]
		As	Cd	Co	Cu	Cr	Fe	Mn	Hg	Mo	Ni	Pb	Se	Zn
Reference Values 1			3–5 a		200–800		940–1220	20			1.8–4.2	10–100 a	220 a	700–2000
General Dog Population
Turkey 1	73			24	830		1320	10			13	100		730	[17]
Poland 2,b	48	556			1363	249	1690	683				489		1523	[18]
Italy 2,c	31	390			780	130		20	510		230	60	230	1970	[19]
Control Healthy Dogs
India 1	10			36.6 ± 3.6	1050 ± 21		872 ± 21	172 ± 2						642 ± 10	[20]
USA 3,d	50			0.30	450		1625	3.15		8.45			300	740	[11]
Bulgaria 2	10				946 ± 143			24 ± 5					291 ± 57	1692 ± 180	[21]
Turkey 4	10				1006 ± 12		860 ± 199							620 ± 76	[22]
USA 1,4	50					4.66 ± 2.83	1751 ± 567							1220 ± 360	[23]
Turkey 4,b	16				511 ± 59		1543 ± 240	20 ± 1							[24]
Iran 4	14				1514 ± 255		1730							593 ± 226	[25]

^a Whole blood, ^b urban area, ^c polluted area, ^d median. Analytical techniques: ¹ atomic absorption spectrophotometer (AAS); ² inductively coupled plasma optical emission spectroscopy (ICP-OES); ³ inductively coupled plasma mass spectroscopy (ICP-MS); ⁴ UV spectrophotometry.