Question

Which of the following isotopes is most dangerous to Homo sapiens?

• A. Phosphorus-32
• B. Strontium-90
• C. Caesium-137
• D. Iodine-131

Answer 1

The correct option is A Phosphorus-32

The radioactive strontium – 90 is most dangerous because it gets fixed in bones and remains in bones leading to bone cancer. It emits high energy beta radiations. Phosphorus – 32 also emit high energy beta radiations but they cannot penetrate human skin. Cesium – 137 (a beta emitter) and iodine – 131 also pose danger to human health but not more than strontium 90.