Table 5.
1. GaAs exposure calculation premised on detecting As concentration of 2.7 mg/m3 in the workplace | |
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2. Calculated weekly nanoparticles lung deposition (mass) in a worker exposed to 5.2 [mg/m] GaAs | |
Assumptions: | |
· Ventilation rate of a healthy human adult: 20 [L/min] | |
· Deposition fraction: 30% | |
· Weekly exposure period: 8 [h/day], 5 [d/week] | |
Weekly lung deposition: | |
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3. Weekly deposition level converted to mass/surface area in the human lung | |
Assumptions: | |
· Human alveolar surface area: 102 [m /person] | |
Calculation: | |
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4. Comparable deposition level in a mouse receiving a one-time installation exposure | |
Assumptions: | |
· Alveolar epithelium surface area of a mouse: 0.05 [m /mouse]; | |
· Weight of a mouse: 25 [g] | |
Calculation: | |
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Our animal experiments were based on a real-life As exposure measurement in a manufacturing facility, where airborne As levels were documented to be as high as 2.7 mg/m3.34 The chosen dose of 0.014 mmol/kg for each of the III-V materials equals to 1–4 mg/kg based on the molar weight in Table 3, which overlaps with the calculated mouse exposure dose of 1.468 [mg/kg].