Comprehensive investigation of carcinogenic radon levels in water within the Ikorodu axis of Lagos State, Nigeria.

This study investigates radon concentration in drinking water from twenty samples collected at two tertiary Institutions in Ikorodu, Lagos State, using the RAD-7 detector. The objective is to evaluate the health risks associated with radon exposure, a known carcinogen linked to lung and stomach cancer. Radon in drinking water contributes to approximately 168 cancer deaths annually, predominantly from lung cancer due to inhalation of radon released indoors and stomach cancer from ingesting contaminated water. The measured radon concentrations ranged from 4.5 ± 1.1 Bq/m³ to 25.5 ± 2.1 Bq/m³, with 70% of samples exceeding the EPA's maximum contamination level of 11.1 Bq/L. Despite these high levels, the annual effective doses from ingestion and inhalation varied from 0.4545 to 24.37 μSv/y, remaining below the global average of 300 μSv/y and WHO limit of 100 μSv/y. While the presence of radon in Ikorodu's water sources indicates a radiological risk, the associated health risks are comparatively low according to international standards. These findings underscore the importance of ongoing monitoring and potential mitigation measures to ensure the continued safety of drinking water in the region.