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Table 5 Particle penetration (50% cut-point) through respiratory tract regions relative to particles entering the respiratory tract

From: Thoracic and respirable particle definitions for human health risk assessment

V daily(%-tile) Normal   Gradual  
  Augmenter Mouth-breather Augmenter Oral only
  P(ET) avg P(TB) avg P(ET) avg P(TB) avg P(ET) avg P(TB) avg P(ET) avg P(TB) avg
Male         
5% 2.94 a 2.74 5.15 4.32 3.60 3.25 9.00 6.67
95% CI (1.72–5.03) (1.65–4.34) (3.12–8.48) (2.84–6.10) (2.11–6.11) (2.00–4.98) (5.86–13.8) (5.00–8.14)
50% 2.46 2.30 5.09 4.30 3.37 3.05 8.09 6.11
95% CI (1.44–4.20) (1.38–3.71) (3.14–8.26) (2.86–5.88) (1.99–5.67) (1.88–4.65) (5.26–12.4) (4.58–7.34)
95% 2.14 2.03 5.08 4.31 3.19 2.90 7.61 5.89
95% CI (1.25–3.66) (1.20–3.32) (3.16–8.16) (2.89–5.83) (1.90–5.33) (1.79–4.44) (4.95–11.7) (4.38–7.07)
Female         
5% 2.92 2.71 4.32 3.78 3.10 2.86 8.78 6.50
95% CI (1.71–5.01) (1.63–4.28) (2.57–7.22) (2.40–5.52) (1.81–5.30) (1.73–4.48) (5.71–13.5) (4.88–7.91)
50% 2.42 2.27 4.46 3.87 2.91 2.68 7.88 5.96
95% CI (1.41–4.13) (1.36–3.64) (2.72–7.32) (2.51–5.45) (1.71–4.94) (1.63–4.19) (5.13–12.1) (4.47–7.17)
95% 2.10 1.99 4.58 3.96 2.74 2.54 7.44 5.77
95% CI (1.23–3.60) (1.18–3.26) (2.82–7.42) (2.60–5.49) (1.61–4.64) (1.53–4.00) (4.84–11.4) (4.29–6.94)
Child-B b         
5% 2.77 2.61 4.31 3.78 4.30 3.78 8.34 6.46
95% CI (1.62–4.75) (1.56–4.18) (2.58–7.19) (2.40–5.57) (2.57–7.17) (2.40–5.56) (5.42–12.8) (4.74–8.04)
50% 2.25 2.13 4.37 3.81 4.07 3.59 7.50 5.81
95% CI (1.31–3.85) (1.27–3.48) (2.67–7.15) (2.47–5.35) (2.46–6.71) (2.29–5.15) (4.88–11.5) (4.32–7.08)
95% 1.89 1.81 4.34 3.76 3.98 3.49 6.91 5.33
95% CI (1.11–3.24) (1.07–2.98) (2.69–7.03) (2.48–5.11) (2.45–6.47) (2.27–4.88) (4.49–10.6) (4.01–6.36)
Child-A c         
5% 3.92 3.56 5.60 4.72 5.59 4.72 8.34 6.46
95% CI (2.29–6.72) (2.18–5.44) (3.38–9.28) (3.09–6.63) (3.37–9.27) (3.09–6.62) (5.42–12.8) (4.74–8.04)
50% 3.18 2.94 5.37 4.53 5.12 4.36 7.50 5.81
95% CI (1.86–5.45) (1.77–4.58) (3.29–8.77) (3.03–6.10) (3.11–8.40) (2.88–5.95) (4.88–11.5) (4.32–7.08)
95% 2.68 2.50 5.16 4.34 4.85 4.14 6.91 5.33
95% CI (1.56–4.58) (1.50–3.97) (3.19–8.34) (2.94–5.66) (2.98–7.90) (2.76–5.51) (4.49–10.6) (4.01–6.36)
  1. P(ET)avg, extrathoracic particle penetration which is the thoracic particle fraction averaged across all activity levels weighted by daily ventilation; P(TB)avg, tracheobronchial particle penetration which is the respirable particle fraction averaged across all activity levels weighted by daily ventilation; 95% CI, ninety-five percent confidence intervals for inter-individual variability attributable to differences in particle penetration through the extrathoracic region; a Aerodynamic particle diameter in μm; b Scaling factor in Equations 2 and 3 equal to 1.26; c Scaling factor in Equations 2 and 3 equal to 1.0.