Mixture of Toxic Metals and Volatile Organic Compounds in a River Induces Cytotoxicity

Table 2

Values of physicochemical parameters, toxic metals, and volatile organic compounds of water samples from different sites of the Atoyac River.

Parameters	Sampling area
	Z1	Z2	Z3
pH (UpH)	6.5 ± 0.2^a	4.9 ± 0.5^a	5.2 ± 0.4
Ec (mS)	0.143 ± 0.02^a	0.246 ± 0.13^a	0.310 ± 0.23^b
TUB (NTU)	145.6 ± 2^a	208 ± 3^b	237.6 ± 3^b
COD (mgL^−1)	62 ± 3^a	189 ± 4^b	192 ± 6^b
BOD5 (mgL^−1)	6.95 ± 0.28^a	34.24 ± 0.94^b	58.79 ± 0.52^b
DO (mgL^−1)	5.5 ± 0.6^a	1.1 ± 0.3^b	0.5 ± 0.2^b
As (mgL^−1)	0.4^a	0.7^a	1.7^b
Cd (mgL^−1)	0.3^a	0.4^a	0.9^b
Cu (mgL^−1)	3.8^a	4.8^a	8.8^b
Cr (mgL^−1)	1.3^a	1.5^a	7.5^b
Hg (mgL^−1)	0.002^a	0.2^b	1.2^c
C6H6 (µgL^−1)	0.02^a	0.3^a	0.5^b
CHCl3 (µgL^−1)	0.05^a	0.05^a	0.30^b
C2HCl3 (µgL^−1)	0.03^a	0.03^a	0.70^b

pH: hydrogen potential; Ec: electrical conductivity; TUB: turbidity; COD: chemical oxygen demand; BOD₅: biochemical oxygen demand; DO: dissolved oxygen; As: arsenic; Cd: cadmium; Cr: chromium; Hg: mercury; C₆H₆: benzene; CHCl₃: chloroform; C₂HCl₃: trichloroethylene; Z1: study area 1; Z2: study area 2; Z3: study area 3. Different literals (a, b, and c) indicate a significant difference between study zones ( < 0.05).