Table 6.

Regulatory levels for soil metals established between different countries.

Order	Country	Concentration (mg kg−1)							Reference
		Pb	Zn	Ni	Cu	Cr	Cd	As
1	Australia	—	200	60	60	50	—	20	[81]
2	Japan	—	—	—	125	—	1	15	[82]
3	Taiwan	100	300	—	150	200	4	20	[83]
4	Turkey	150	500	—	100	—	5	—	[84]
5	EU	300	300	75	140	150	3	—	[85]
6	Netherlands	150	500	100	100	250	5	—	[86]
7	Spain	300	450	112	210	150	3	—	[87]
8	Germany	100	300	50	100	100	3	20	[88]
9	France	100	300	50	100	150	2	20	[89]
10	UK	550	280	35	140	600	4	10	[90]
11	USA	150	300	31	45	212	2	5.6	[91]
12	Canada	500	500	100	100	250	5	—	[92]