Table 1.

Seasonal statistics of the PM_2.5 components.

Seasona	PM2.5	SO42−b	Percentc	OC	Percent	EC	Percent	BC	Percent
Winter	9.22 ± 4.68d	3.00 ± 1.61	32.5	3.31 ± 1.18	35.9	0.43 ± 0.25	4.7	0.52 ± 0.34	5.6
Summer	12.35 ± 7.16	5.14 ± 3.95	41.6	3.55 ± 1.24	28.7	0.43 ± 0.19	3.5	0.71 ± 0.31	5.7
Transition	7.78 ± 5.22	3.05 ± 2.78	39.2	3.13 ± 1.17	40.2	0.36 ± 0.20	4.6	0.54 ± 0.30	6.9
Overall	9.31 ± 6.02	3.64 ± 3.11	39.1	3.28 ± 1.21	35.2	0.39 ± 0.21	4.2	0.58 ± 0.32	6.2

Notes:

^aWinter (December to February), summer (June to August), transition (March to May and September to November).

^bEquivalent of (NH₄)₂SO₄.

^cWeight percent of the PM_2.5 concentration.

^dAverage ± standard deviation.