Assessment of Radio Frequency Electromagnetic Exposure Levels Near Base Stations in Onitsha, Anambra State

Public concern about health effects of radio frequency electromagnetic field emissions from telecommunications base stations has grown alongside the rapid densification of mobile network infrastructure in Nigerian commercial cities. This study assesses RF-EMF exposure levels near base transceiver stations in Onitsha, Anambra State, South East Nigeria, a major commercial hub with high infrastructure density. Field measurements of power density were conducted using a broadband RF measurement instrument at distances of 5, 10, 25, 50, and 100 meters from twenty-two base station installations spanning rooftop, guyed mast, and monopole configurations operated by MTN, Airtel, and Glo. Measurements were collected during business hours and compared against the International Commission on Non-Ionizing Radiation Protection guidelines and NCC's electromagnetic exposure limits. Results indicate that measured power density values at all sampled distances fell well below the ICNIRP reference levels, with the highest recorded value representing only 4.7% of the applicable limit at 5 meters from the nearest antenna. No measurement point exceeded 12% of the permissible exposure limit. The study finds no evidence of excessive public RF-EMF exposure from properly installed and regulated base stations in Onitsha. However, unauthorized rooftop antennas at residential buildings were identified as potential exceptions requiring targeted inspection. Recommendations include mandatory public information placards at base station sites and periodic NCC compliance audits. Keywords: RF exposure, base station, electromagnetic field, Onitsha, ICNIRP compliance.