This paper discusses the radiological characterisation of synthetic rutile, which is the source material for the production of titanium. The natural radioactivity due to uranium (²³⁸U), thorium (²³²Th) series radionuclides and potassium (⁴⁰K) was measured in synthetic rutile samples of a production plant in Tamil Nadu, India. n-type high-purity germanium-coupled gamma spectrometry was used for the analysis. It is observed that thorium is more abundant than any other radionuclide, which is due to the monazite present in the primary sand. The activity index (I) evaluated from the radioactivity concentrations of ²²⁶Ra, ²³²Th and ⁴⁰K of the analysed samples is found to be well below the recommended levels. This study shows that the use of synthetic rutile from Tamil Nadu, India, for the manufacture of building materials will not pose any increased radiation exposure to the public beyond the dose criterion of the European Union.