Research Article

Air Quality and Human Health Risk Assessment in the Residential Areas at the Proximity of the Nkolfoulou Landfill in Yaoundé Metropolis, Cameroon

Table 5

WHO ambient air quality standards.

PollutantAveraging durationMaximum allowable limitReference

PM2.524 hours25 μg/m3[6]
Annual10 μg/m3[6]
PM1024 hours50 μg/m3[6]
Annual20 μg/m3[6]
CO15 minutes100 mg/m3[5]
30 minutes60 mg/m3[5]
1 hour30 mg/m3[5]
8 hours10 mg/m3[5]
SO210 minutes500 µg/m3[6]
24 hours20 μg/m3[6]
CH2O30 minutes0.1 mg/m3[5]
H2S24 hours150 μg/m3[5]
O38 hours100 μg/m3[6]
NO21 hour200 μg/m3[5]
Annual40 μg/m3[5]