Table 3 Difference of the components of PM2.5 between March and July sampled in Ulaanbaatar, Mongolia

Mass concentration (μg/m ³ )

PM2.5

60.29 ± 15.48

58.71

40.74–81.49

9.72 ± 2.59

10.52

6.57–12.71

<0.0005

Carbon (μgC/m ³ )

Organic

21.47 ± 7.00

18.78

13.51–31.93

2.22 ± 0.95

2.63

080–3.29

<0.005

Elemental

7.72 ± 1.68

7.39

5.80–10.77

1.52 ± 0.57

1.61

0.75–2.15

<0.0005

Total

29.19 ± 8.58

26.18

19.36–42.70

3.73 ± 1.50

4.22

1.54–5.19

<0.001

Ion (μg/m ³ )

Cl⁻

0.710 ± 0.22

0.646

0.556–1.176

0.0302 ± 0.0197

0.0254

0.0106–0.0716

<0.001

NO₃ ⁻

2.60 ± 0.86

2.77

1.49–3.47

0.0496 ± 0.0477

0.0471

N.D.–0.1169

<0.001

SO₄ ²⁻

3.83 ± 0.98

4.37

2.26–4.58

0.5260.156

0.522

0.764

<0.0005

Na⁺

0.0846 ± 0.0194

0.0846

0.0604–0.1084

0.0183 ± 0.0100

0.0174

0.0085–0.0390

<0.0005

NH₄ ⁺

2.80 ± 0.65

3.04

1.71–3.42

0.206 ± 0.072

0.194

0.115–0.317

<0.0005

K⁺

0.0242 ± 0.0250

0.0138

0.0024–0.0637

0.000681 ± 0.001370

N.D.

N.D.–0.003639

N.S.

Mg²⁺

N.D.

N.D.

N.D.

N.D.

N.D.

N.D.

–

Ca²⁺

0.290 ± 0.064

0.265

0.227–0.371

0.262 ± 0.098

0.284

0.111–0.407

N.S.

Metal (ng/m ³ )

Na

111.75 ± 39.91

100.84

65.86–165.06

67.57 ± 109.06

28.03

16.03–314.64

N.S.

Al

113.10 ± 68.34

115.55

34.11–204.03

62.65 ± 90.09

21.68

N.D.–234.25

N.S.

Si

108.74 ± 47.95

111.34

46.51–163.46

89.81 ± 84.82

56.57

20.96–266.00

N.S.

K

116.17 ± 35.86

101.89

74.88–172.71

112.97 ± 154.26

51.86

41.74–461.23

N.S.

Ca

315.09 ± 149.22

265.58

193.68–559.36

192.02 ± 106.51

172.92

80.57–392.83

N.S.

Sc

0.0184 ± 0.0076

0.0203

0.0050–0.0257

0.0104 ± 0.0079

0.0079

0.0026–0.0245

N.S.

Ti

6.16 ± 2.60

4.95

3.69–10.14

4.93 ± 2.77

3.42

3.20–10.16

N.S.

V

0.482 ± 0.134

0.485

0.267–0.637

0.174 ± 0.110

0.137

0.061–0.402

<0.005

Cr

14.36 ± 10.81

12.777

N.D.–28.059

0.772 ± 1.787

N.D.

N.D.–4.793

<0.05

Mn

4.80 ± 1.05

4.96

3.48–6.20

4.28 ± 1.81

3.74

2.29–7.58

N.S.

Fe

217.82 ± 114.46

276.11

67.41–322.63

86.65 ± 43.46

87.67

34.73–167.96

<0.05

Co

0.115 ± 0.034

0.112

0.060–0.157

0.0455 ± 0.0265

0.0339

0.0285–0.1029

<0.005

Ni

0.469 ± 0.203

0.448

0.154–0.778

0.110 ± 0.049

0.096

0.056–0.184

<0.01

Cu

4.68 ± 2.68

3.82

2.51–9.69

1.73 ± 0.46

1.52

1.08–2.33

<0.05

Zn

53.02 ± 27.04

51.33

27.64–101.61

18.14 ± 17.19

12.25

2.82–49.45

<0.05

As

14.14 ± 4.77

13.97

8.39–22.61

0.409 ± 0.267

0.33

0.21–0.99

<0.001

Se

0.233 ± 0.092

0.234

0.106–0.349

0.0724 ± 0.0386

0.0562

0.0384–0.1441

<0.01

Rb

0.338 ± 0.068

0.330

0.265–0.425

0.162 ± 0.062

0.138

0.114–0.286

<0.001

Mo

0.133 ± 0.071

0.131

0.033–0.227

0.0352 ± 0.0319

0.0225

0.0133–0.1031

<0.05

Sb

0.988 ± 0.422

1.065

0.412–1.414

0.466 ± 0.277

0.621

0.114–0.800

<0.05

Cs

0.0816 ± 0.0276

0.0771

0.0511–0.1308

0.0197 ± 0.0108

0.0145

0.0120–0.0388

<0.005

Ba

29.84 ± 39.18

6.74

3.44–95.01

3.31 ± 2.74

2.15

1.82–9.43

N.S.

La

0.0955 ± 0.0383

0.0795

0.0626–0.1445

0.198 ± 0.171

0.150

0.050–0.512

N.S.

Ce

0.197 ± 0.077

0.169

0.128–0.291

0.143 ± 0.076

0.109

0.072–0.288

N.S.

Sm

0.0163 ± 0.0077

0.0127

0.0099–0.0261

0.0110 ± 0.0073

0.0077

0.0059–0.0255

N.S.

Hf

0.00293 ± 0.00170

0.00266

0.00090–0.00588

0.00151 ± 0.00079

0.00116

0.00066–0.00301

N.S.

Ta

0.000345 ± 0.000387

0.000290

N.D.–0.001039

0.000040 ± 0.000105

N.D.

N.D.–0.000278

N.S.

W

0.211 ± 0.169

0.141

0.034–0.462

0.0220 ± 0.0299

0.0076

0.0070–0.0883

<0.05

Pb

12.34 ± 5.73

10.41

8.29–23.56

12.27 ± 11.42

6.92

2.67–34.15

N.S.

Th

0.0232 ± 0.0152

0.0174

0.0083–0.0459

0.00964 ± 0.00633

0.00675

0.00522–0.02305

N.S.