Correct Option
Researchers using Carbon 14 isotope: Carbon-14 is a radioactive isotope that undergoes beta decay, emitting beta particles. Beta radiation is a form of ionizing radiation. Ionizing radiation has the capacity to damage DNA molecules directly or indirectly, leading to mutations if cellular repair mechanisms are insufficient. Professionals working with such isotopes are at an increased risk of permanent DNA changes, especially with prolonged or unprotected exposure.
X-ray technician: X-rays are a form of ionizing electromagnetic radiation. Exposure to ionizing radiation is a well-established cause of DNA damage, including single and double-strand breaks, base modifications, and chromosomal aberrations. These alterations can lead to permanent genetic mutations. X-ray technicians, due to their occupational exposure, face this risk, necessitating strict adherence to safety protocols.
Dyer and painter: These professionals are frequently exposed to a range of chemicals, including organic solvents, dyes, and pigments. Many of these substances are known mutagens (agents that cause genetic mutations) and carcinogens (agents that cause cancer). Chronic occupational exposure to such chemicals can directly interact with DNA, inducing damage and subsequent mutations.
Incorrect Options
Coal miner: Coal miners are primarily exposed to coal dust, which is associated with respiratory diseases such as pneumoconiosis (black lung disease) and chronic bronchitis. While prolonged inflammation and oxidative stress can indirectly affect cellular processes, coal dust itself is not typically classified as a direct mutagen that causes permanent DNA changes through mechanisms like ionizing radiation or specific chemical mutagens. Therefore, the risk of direct DNA mutation from coal dust exposure is not significant in the context of this question.
Options (a), (b), and (d) are incorrect because they either exclude professions that are at risk (1 and 4) or include a profession (3) that is not primarily associated with the direct risk of permanent DNA changes as described.