Table 1.

Mean air pollutant (NO₂, PM_2.5, and PM₁₀) concentrations in different study sites (expressed in micro-g/m³).

Site:	Walbrzych			Wroclaw			Lodz			Krakow
	NO2	PM2.5	PM10	NO2	PM2.5	PM10	NO2	PM2.5	PM10	NO2	PM2.5	PM10
2010	15.66	27.91		37.69	33.11	56.99	26.91	30.08	44.21	46.21	45.57	64.90
2011	17.52	21.76		43.06	31.52	48.80	25.90	27.75	37.38	45.31	44.59	64.77
2012	16.81	22.39	26.58	37.27	29.58	38.09	25.54	26.44	35.90	43.19	41.83	59.42
2013	14.35	23.81	33.27	44.04	29.09	36.31	25.41	26.48	39.52	39.98	35.35	50.20
2014	13.79	24.36	31.78	35.20	27.13	40.68	23.00	28.09	40.37	38.12	34.64	50.36
2015	15.02	18.91	27.22	31.94	25.38	33.58	24.81	24.57	37.24	40.93	35.09	51.28
2016	15.66	18.88	27.44	31.08	23.95	33.28	25.28	22.85	35.81	41.05	29.61	40.98
2017	15.21	21.39	27.06	28.62	22.01	30.18	24.33	25.87	38.29	41.07	32.84	42.90
2018	15.22	21.58	28.75	27.90	22.08	30.09	25.03	24.38	36.63	40.35	29.69	40.68
2019	13.11	15.36	23.09	26.16	17.15	25.36	21.46	20.17	31.96	39.02	24.82	34.83
Total	15.25	21.61	28.14	34.28	26.10	37.34	24.77	25.67	37.73	41.52	35.40	50.03
Site:	Warsaw			Gdansk			Szczecin
	NO2	PM2.5	PM10	NO2	PM2.5	PM10	NO2	PM2.5	PM10
2010	32.80	29.00	38.06	18.52	20.22	27.86	23.05	18.74	29.66
2011	33.06	28.48	36.96	17.43	17.86	24.83	20.72	17.70	27.44
2012	28.73	28.03	36.51	16.91	18.24	23.23	20.14	16.27	22.69
2013	38.26	25.03	32.64	15.37	13.43	20.09	30.73	15.64	22.93
2014	35.36	25.26	33.23	17.00	16.62	25.76	22.16	19.60	25.94
2015	38.33	22.55	33.10	17.24	13.57	22.89	21.63	16.26	23.69
2016	37.15	21.86	33.52	16.71	11.44	20.07	21.97	16.40	23.31
2017	34.41	23.26	34.81	16.46	11.70	20.48	18.72	17.13	22.69
2018	34.53	22.15	36.35	17.65	15.94	26.45	20.71	18.75	24.72
2019	29.73	17.45	27.64	15.54	13.90	21.25	14.47	14.54	21.05
Total	34.23	24.31	34.28	16.88	15.29	23.29	21.43	17.10	24.41