Potential Impacts of the Introduction of Low-Sulfur Fuel on PM_𝟐.𝟓 Concentrations at Breathing Level in a Subarctic City

Table 2

Monthly mean of 24 h-averaged PM_2.5, PM₁₀, sulfate, and nitrate concentrations in the nonattainment area as obtained with REF (first value) and LSF (second value) and percent change (in brackets). Reductions are presented negative. Bold values indicate significant changes.

	October	November	December	January	February	March	October to March
PM2.5 (μg/m^3)	𝟏𝟑.𝟎∣𝟏𝟐.𝟓; (−4%)	11.0∣10.0; (−𝟗%)	9.2∣8.5; (−8%)	11.0∣10.4; (−6%)	9.8∣9.3; (−5%)	5.7∣5.3; (−7%)	9.5∣8.9; (−6%)
PM10 (μg/m^3)	𝟐𝟗.𝟒∣𝟐𝟖.𝟔; (−3%)	28.2∣25.9; (−𝟖%)	24.1∣22.4; (−7%)	26.6∣25.2; (−6%)	24.2∣23.0; (−5%)	15.3∣14.3; (−7%)	23.6∣22.2; (−6%)
Sulfate (μg/kg·dryair)	𝟐.𝟏𝟓∣𝟐.𝟎𝟕; (−3%)	1.79∣1.64; (− 𝟖%)	1.49∣1.38; (−7%)	1.76∣1.67; (−5%)	1.61∣1.52; (−6%)	0.98∣0.91; (−7%)	1.56∣1.47; (−6%)
Nitrate (μg/kg·dryair)	0.09∣0.10; (+3%)	𝟎.𝟏𝟐∣𝟎.𝟏𝟏; (−𝟏𝟎%)	0.05∣0.04; (−𝟏𝟎%)	0.06∣0.06; (−8%)	0.06∣0.06; (+10%)	0.02∣0.02; (−10%)	0.06∣0.06; (−4%)
Ammonium × 10^-3	2.64∣2.75; (+4%)	2.84∣2.83; (0%)	1.71∣1.71; (0%)	2.09∣2.28; (+9%)	𝟐.𝟓𝟎∣𝟐.𝟑𝟒; ( −6% )	1.36∣1.35; (+1%)	2.19∣2.21; (−1%)
Elemental carbon	0.92∣0.89; (−4%)	𝟎.𝟕𝟕∣𝟎.𝟕𝟎; (−𝟗%)	0.62∣0.58; (−8%)	0.75∣0.71; (−6%)	0.68∣0.64; (−6%)	0.40∣0.37; (−7%)	0.69∣0.65; (−6%)
Organic carbon	4.72∣4.55; (−4%)	𝟑.𝟗𝟏∣𝟑.𝟓𝟕; (−𝟗%)	3.19∣2.94; (−8%)	3.83∣3.61; (−6%)	3.49∣3.28; (−6%)	2.02∣1.87; (−7%)	3.53∣3.31; (−6%)