Table 6.

Analysis of heavy metals speciation.

Fraction	Description	Pb	Cu	Cr	Zn	As	Sn
1	Exchangeable	09.34%	06.44%	07.98%	09.55%	11.53%	14.64%
2	Bound to carbonates	18.34%	15.44%	17.98%	19.55%	27.53%	33.64%
3	Bound to oxides	23.76%	26.19%	24.15%	23.98%	28.21%	42.12%
4	Bound to organics	26.16%	28.91%	30.75%	33.58%	40.53%	52.40%
5	Residual or inert	57.56%	52.98%	61.45%	63.12%	59.52%	71.29%
	Sum of concentration of metals (mg/kg)	22.55	22.82	17.07	22.52	06.28	56.30
	Potential mobility	52.73%	54.88%	42.34%	52.12%	16.72%	89.14%