This study investigated the levels and health risk of ambient air pollutants in selected industrialized (Pabod, Mothercat and Slaughter) zones of Port Harcourt City, Nigeria. Standard air pollution monitoring equipment were employed. It involved the determination of the levels of CO2, NO2, SO2, CO, O3, CH4, NH3, VOC, relative humidity, noise level and particulate matters. Results of the study revealed that SO2, NO2, O3, and NH3 were not detected. The mean of PM2.5 was 28.95±5.050 μg/m3 for Pabod area, Slaughter; 81.55±4.650 μg/m3; Mothercat; 40.80±0.650 μg/m3. PM10 was 158.3±17.80 μg/m3 for the Slaughter, Mothercat; 57.65±0.650 μg/m3, Pabod; 42.50±3.800 μg/m3. CO was 0.300±0.100 ppm for Pabod, and1.10±0.10 ppm for slaughter. VOC, Pabod; 0.065±0.01 μg/m3, Slaughter; 0.175±0.030 ppm, mothercat; 0.050±0.01 ppm. Relative humidity was low across the three areas sampled. The noise level was highest in slaughter. The non-carcinogenic risks linked with the contact to H2S in Pabod had 3.751 which is a high risk. The AQI indicated poor quality especially for slaughter and pabod areas. It is therefore recommended that periodic risk assessment of these areas be carried out from time to time to determine the levels of air pollutants.