Table 1.

Sampling periods, numbers of samples, and Σ7PAH and Σ15PAH concentrations, 2007–2016.

Observation period		No. of samples	Σ7PAHs (ng m−3)	Σ15PAHs (ng m−3)
2007	8/1–8/7	14	0.521	ND
2008	7/22–7/29	15	1.15	ND
2009	2/23–2/28	10	1.95	ND
	5/26–5/31	9	0.521	ND
	7/17–7/27	22	1.04	ND
	10/19–10/27	15	1.09	ND
2010	5/24–5/28	10	0.514	ND
	7/12–7/16	9	0.240	ND
	10/18–10/22	10	0.554	ND
	12/6–12/13	11	0.924	ND
2011	3/7–3/11	9	0.922	ND
	5/16–5/20	10	0.754	ND
	7/11–7/22	20	0.664	ND
	10/3–10/7	8	1.03	ND
	12/12–12/16	10	1.44	ND
2012	3/19–3/23	8	1.72	2.76
	5/14–5/18	9	1.25	1.88
	7/12–7/19	14	1.42	2.16
	8/17–8/24	12	0.773	1.28
	10/22–10/26	9	0.397	0.73
	12/3–12/7	10	0.889	1.53
2013	3/18–3/22	10	0.982	1.46
	5/13–5/17	9	1.29	1.97
	7/29–8/2	10	1.27	2.07
	8/15–8/22	13	0.481	0.761
	10/7–10/11	10	0.274	0.545
	12/2–12/6	9	1.89	2.69
2014	5/12–5/16	10	0.968	1.96
	7/13–7/19	13	0.899	1.76
	8/21–8/25	9	0.214	0.496
	10/20–10/24	10	1.43	2.75
	12/1–12/5	10	1.55	3.49
2015	4/6–4/10	10	1.17	1.90
	7/15–7/23	17	2.90	5.42
	8/18–8/21	6	3.11	6.29
	10/26–10/30	12	2.99	5.93
	11/30–12/4	10	2.44	6.24
2016	4/4–4/8	9	0.428	0.872
	7/12–7/15	7	0.390	0.629
	8/17–8/21	8	0.399	0.641

ND no data.