a radioactive fission product of nuclear explosions and sccidents is often iodine 131 which becomes distributed in the atmosphere. this falls upon the ground and is absorbed by plants. explain how this radiation could eventually beome concentrated in the human body and cause growth disorder.

The concentration of radioactive iodine-131 in the human body and its potential to cause growth disorders can be explained through a process known as biomagnification.

1. Atmospheric Distribution: During a nuclear explosion or accident, radioactive iodine-131 is released into the air. It can travel over large distances due to wind and atmospheric conditions.

2. Deposition on the Ground: As it disperses in the atmosphere, iodine-131 eventually falls to the ground through precipitation or other mechanisms. This process is known as deposition.

3. Absorption by Plants: Once on the ground, iodine-131 can be absorbed by plants through their roots. Plants readily take up iodine, similar to how they absorb other essential nutrients from the soil.

4. Ingestion by Herbivores: Animals that consume these contaminated plants, such as cows or sheep, ingest iodine-131 as part of their diet. The iodine is then assimilated into their tissues.

5. Consumption by Carnivores/Omnivores: When humans consume the contaminated meat/milk of these animals, they also ingest iodine-131. This way, the radioactive iodine enters the human food chain.

6. Concentration in Human Body: Iodine is essential for the proper functioning of the thyroid gland, which regulates growth and metabolism. The human body cannot distinguish between radioactive and non-radioactive iodine, so when iodine-131 is ingested, it is accumulated by the thyroid gland as it absorbs iodine.

7. Chronic Exposure: As humans continue to consume food and water that contains iodine-131, the radioactive isotopes slowly accumulate in the thyroid gland. Over time, the radiation emitted by the iodine-131 can disrupt the normal functioning of the thyroid, leading to growth disorders and other health issues.

It's important to note that the severity of the growth disorders or other health effects directly depends on the amount of iodine-131 ingested, the duration of exposure, and individual variations in susceptibility to radiation.