A study by Kannur University has found the presence of radioactive elements in building materials used in Kannur district, which is witnessing rapid urbanisation. Radioactive elements cause cancer and infertility, it said.
The study titled ‘Radiological threat to humans in the context of alarming urbanisation; a geographical enquiry on concentration of radionuclides in building materials used in Kannur’ has been published in the Journal of Radioanalytical and Nuclear Chemistry.
The research team comprised K.P. Shimod, head of the department of geography, Government College, Tholanur; V. Vineethkumar, faculty member, department of physics, Kasaragod Government College; T.K. Prasad, head of the department of geography, Kannur University; G. Jayapal, former research scholar, and C.V. Vishnu, physical researcher scholar, Calicut university.
Mr. Prasad said assessing people’s exposure to activity concentration of radionuclides in building materials was significant as most people spend 80% of their lifetime indoors. He added that building materials based on sand, sediment, stone, cement, and brick had the highest concentration of radionuclides.
Maintaining that natural radioactivitiy causes exposure of inhabitants to internal and external radiation, he said it mostly came from uranium, thorium, and a radioactive isotope of potassium.
Internal exposure is caused by radon gas breathing, while release of penetrating gamma rays from radioactive sources triggers external exposure. Though radionuclides are widely distributed in the environment, their accumulation depends on the geological assemblage of the environment, he added.
Widely used materials such as laterite stone, tile, cement, marble, granite, rock powder, hollow bricks, sand, and tiles were used for the study, and various radiological parameters were determined. The samples were collected from Kannur, Thalassery, Taliparamba and Payyannur regions.
The study found that radionuclides were higher than the international average in granite, hollow bricks, and rock powder when compared to the internationally recognised limits.
Incidentally, Kannur district is witnessing rapid urbanisation, and the built-up area has gone up from 124.8 sq km to 194.43 sq km in the last 10 years. At present, the construction sector is the main employment generator in the district.
The study also recommended use of alternative building materials to minimise health hazards and in-depth studies to identify the sources of natural radionuclides present in building materials.
