Adesina Kolawole E, Specht Aaron J, Olaniyan Suaib D, Ignatius Catherine, Idowu Opeyemi P, Jubril Ramotallah D, Hamzat Toheeb T, Ndoma Emmanuel G, Olatunji Olalekan
School of Health Sciences, Purdue University, West-Lafayette, IN 47906, United States of America.
School of Health Sciences, Purdue University, West-Lafayette, IN 47906, United States of America; Harvard T.H. Chan School of Public Health, Boston, MA 02115, United States of America.
Sci Total Environ. 2025 Jun 15;981:179478. doi: 10.1016/j.scitotenv.2025.179478. Epub 2025 May 6.
Indoor radon exposure is a significant public health concern, as it is the second leading cause of lung cancer globally. This systematic review evaluated radon concentrations and associated health risks in Nigerian buildings, including homes, schools, and workplaces, through various monitoring techniques such as CR-39 detectors and RAD7 monitors. A total of 47 eligible studies were included following PRISMA guidelines that covered the spatial variations of radon exposure across Nigeria, revealed a weighted mean indoor radon concentration of 104 Bq/m, exceeding the WHO reference level of 100 Bq/m but below the USEPA action level of 148 Bq/m. Certain locations such as Odo-Ona, Ibadan, recorded 531.85 Bq/m, corresponding to an annual effective dose of 13.42 mSv/yr, an excess lifetime cancer risk of 51.66 × 10, and an estimated lung cancer burden of 242 cases/year per million people. Other regions, including Sokoto Metropolis and Oke-Ogun, also exceeded safety limits, while coastal areas like Lagos showed the lowest concentrations (7.52 Bq/m). Geographic disparities were evident, with southwestern Nigeria showing the highest risk and accounting for 63 % of studies, while northern and southeastern regions remain underrepresented. Comparative analysis revealed that Nigerian hotspots surpass radon levels reported in several radon-prone countries, including Bulgaria and Northwest Spain, highlighting a significant health risk. This review presents Nigeria's first indoor radon exposure map in residential and occupational settings nationwide that clearly identified critical hotspots and emphasizing the urgent need for targeted interventions. Awareness of the presence of radon and its potential health effects is very low in Nigeria. Radon mitigation should integrate geological assessments with radon-resistant construction materials, proper ventilation, and sealed entry points, especially in uranium-rich and permeable soils. Public awareness, routine monitoring, and regulatory policies are essential, while future research should focus on underrepresented regions and uncover long-term exposure patterns.
室内氡暴露是一个重大的公共卫生问题，因为它是全球肺癌的第二大主要病因。本系统评价通过CR - 39探测器和RAD7监测仪等各种监测技术，评估了尼日利亚建筑物（包括家庭、学校和工作场所）中的氡浓度及相关健康风险。按照PRISMA指南共纳入了47项符合条件的研究，这些研究涵盖了尼日利亚各地氡暴露的空间变化，结果显示室内氡浓度加权平均值为104 Bq/m³，超过了世界卫生组织100 Bq/m³的参考水平，但低于美国环境保护局148 Bq/m³的行动水平。某些地点，如伊巴丹的奥多 - 奥纳，记录的氡浓度为531.85 Bq/m³，对应年有效剂量为13.42 mSv/年，终生患癌超额风险为51.66×10⁻³，估计每百万人口每年肺癌负担为242例。包括索科托市和奥凯 - 奥贡在内的其他地区也超过了安全限值，而像拉各斯这样的沿海地区浓度最低（7.52 Bq/m³）。地理差异明显，尼日利亚西南部风险最高，占研究的63%，而北部和东南部地区的研究较少。比较分析表明，尼日利亚的热点地区氡水平超过了包括保加利亚和西班牙西北部在内的几个氡易发国家报告的水平，突出了重大的健康风险。本评价给出了尼日利亚全国住宅和职业环境中的首张室内氡暴露地图，明确确定了关键热点地区，并强调了针对性干预的迫切需求。在尼日利亚，对氡的存在及其潜在健康影响的认识非常低。氡减排应将地质评估与防氡建筑材料、适当通风和密封入口点相结合，特别是在富铀和渗透性土壤地区。公众意识、常规监测和监管政策至关重要，而未来的研究应侧重于研究较少的地区，并揭示长期暴露模式。
