| Gűndoğdu et al., 2018 [146] | 17 | 4.11 particles/L | n.a. | Secondary | 79% | Turkey (Yűreğir) |
| Estahbanadi and Fahrenfeld 2016 [116] | 18 | 0.028 to 0.44 particles/L | 250 - 500 | Primary and secondary | n.a. | USA |
| Kalčiková et al., 2017 [147] | 19 | 0.021 particles/L | 37 to 95 | Primary (Mechanical and Biological) | 87% | Slovenia |
| Simon et al., 2018 [148] | 20 | 54 particles/L | 10 to 500 | - | 98.3% | Denmark |
| Sutton et al., 2016 [141] | 21 | 0.071 particles/L | 125 | Primary and secondary | n.a. | USA |
| Michielssen et al., 2016 [115] | 22 | 5.9 particles/L | 20 | Primary and secondary | 93.8% | USA (Detroit) |
| Michielssen et al., 2016 [115] | 23 | 37.4 particles/L | 20 | Primary and secondary | 89.8% | USA (Northfield) |
| Gies et al., 2018 [149] | 24 | 0.5 particles/L | 64 | Primary and secondary | 98.3% | Canada |
| Wisniowska et al., 2018 [150] | 25 | 0.028 to 0.96 particles/L | n.a. | n.a. | 95% - 99% | Poland |
| Yang et al., 2019 [151] | 26 | 0.59 particles/L | 50 | Primary and secondary | 95% | China (Beijing) |
| Bayo et al., 2019 [152] | 27 | 0.25 particles/L | n.a | Primary | 90.3% | Spain (Cartagena) |
| Long et al., 2019 [153] | 28 | 0.20 e 1.73 items/L | 28.3 | Primary and secondary | 97.8% | China (Xiamen) |
| Blair et al., 2019 [154] | 29 | <1 and 3 particles/L | 300 | Tertiary | 96% | UK |
| Xu et al., 2019 [155] | 30 | 9.04 particles/L | 1000 | Primary and secondary | 97.2% | China (Changzhu) |
| Lv et al., 2019 [156] | 31 | 0.13 and 0.05 particles/L | 25 | n.a. | MBR 99.5%, OD 97% | China |
| Liu et al., 2019 [157] | 32 | 28.4 particles/L | 100 | Primary and secondary | 64.4% | China |
| Wolff et al., 2019 [158] | 33 | 59 and 30 particles/L | 10 | Primary and secondary | n.a | Germany |
| Conley et al., 2019 [159] | 34 | 3.7, 17.6 and 17.2 particles/L | 23 | Primary and secondary | 97.6%, 85.2%, 85.5% | USA (South Carolina) |
| Magni et al., 2019 [160] | 42 | 0.4 particles/L | 8 | Primary, Secondary and tertiary | 84% | Italy |