Table 1. Metal levels (mg L⁻¹) in the Água Boa stream water samples from April 2013 to October 2013.

Sample	Month	Copper (Cu)	Iron (Fe)	Manganese (Mn)	Cadmium (Cd)	Cobalt (Co)	Lead (Pb)	Nickel (Ni)
P1 (surface water)	April	0.0506*	0.8165	< DL	< DL	0.2461*	0.2565*	0.3740*
	July	#	#	#	#	#	#	#
	September	0.0261*	0.9651	< DL	0.0305*	0.0227	< DL	0.2193*
	October	0.0570*	0.4107	< DL	< DL	0.1957	0.2076*	0.2910*
P2 (surface water)	April	0.0673*	1.218	< DL	0.0468*	0.1123	< DL	< DL
	July	< DL	0.9331	< DL	< DL	0.1004	< DL	0.0740*
	September	0.0274*	1.257	0.0450	< DL	0.1849	< DL	0.2258*
	October	0.0661*	0.6715	0.0190	< DL	0.2533*	0.2377*	0.2959*
P3 (surface water)	April	< DL	0.8110	< DL	< DL	0.1183	< DL	0.0823*
	July	< DL	1.2550	< DL	0.0328*	0.1201	< DL	0.1785*
	September	0.0261*	0.8179	< DL	< DL	0.1843	0.2076*	0.2366*
	October	0.0661*	0.5578	< DL	< DL	0.2227*	0.2189*	0.2502*
P4 (groundwater)	April	0.0223	0.1697	< DL	0.0308	< DL	< DL	< DL
	July	0.0990	0.11	< DL	< DL	0.1147	< DL	< DL
	September	0.0274	< DL	< DL	0.0298	0.2137	< DL	0.1964**
	October	0.0490	0.0930	< DL	0.0202	0.1094	< DL	0.0654**
Permitted levels
CONAMA 357/2005 (surface water)		0.013	5.0	0.5	0.01	0.2	0.033	0.025
CONAMA 396/2008 (ground water)		2	0.3	0.1	0.005	–	0.01	0.02

Limits of detection (LOD): 0.007 mg L⁻¹ Cu, 0.014 mg L⁻¹ Fe, 0.005 mg L⁻¹ Mn, 0.008 mg L⁻¹ Cd, 0.021 mg L⁻¹ Co, 0.060 mg L⁻¹Pb, 0.018 mg L⁻¹Ni. Limits of quantification (LOQ): 0.026 mg L⁻¹ Cu, 0.049 mg L⁻¹ Fe, 0.017 mg L⁻¹ Mn, 0.029 mg L⁻¹ Cd, 0.073 mg L⁻¹ Co, 0.203 mg L⁻¹ Pb, 0.062 mg L⁻¹ Ni. DL: Detection Limit

^*Values higher than allowed according to CONAMA 357/2005.

^**Values higher than allowed according CONAMA 396/2008.

^#No sample collected. – Value not found