Determination of Lead, Cations, and Anions Concentration in Indoor and Outdoor Air at the Primary Schools in Kuala Lumpur

Table 4

Concentration of SO₄²⁻ and NO³⁻ for both indoor and outdoor air according to sampling stations.

Sampling station	SO4^2− (mg/g)		NO^3− (mg/g)
	Indoor	Outdoor	Indoor	Outdoor
A	21.76 ± 1.13	22.89 ± 2.04	25.36 ± 0.76	31.10 ± 0.08
B	22.81 ± 0.55	23.09 ± 1.35	23.17 ± 1.56	32.00 ± 0.75
C	23.42 ± 1.91	23.95 ± 2.51	21.79 ± 0.38	30.93 ± 0.41
D	23.05 ± 2.43	23.38 ± 2.74	22.53 ± 1.21	30.72 ± 0.26
E	22.76 ± 1.81	23.73 ± 1.21	24.80 ± 0.58	29.53 ± 0.63
F	22.71 ± 2.14	24.52 ± 1.03	21.34 ± 0.97	29.72 ± 0.31