The Eu (half life 8.59 year) were mainly formed by the neutron activation of the europium in the soil, it is clear that the level of radioactivity for these isotopes is highest where the neutron dose to the soil was larger.
Some of the Am (half life 432.6 year) are due to the neutron activation of barium and plutonium inside the bomb.
This paper also reports details of the effect of potassium, ammonium and calcium ions on the uptake of the radioisotopes.
Caesium binds tightly to clay minerals such as illite and montmorillonite; hence it remains in the upper layers of soil where it can be accessed by plants with shallow roots (such as grass).
An example of a medium lived is Cs, which has a half-life of 30 years.
Caesium is released in bomb fallout and from the nuclear fuel cycle.
Busby quotes a report on the plutonium activity in Welsh intertidal sediments by Garland et al.
The The action of neutrons on stable isotopes can form radioisotopes, for instance the neutron bombardment (neutron activation) of nitrogen-14 forms carbon-14.Using milk as an example, if the cow has a daily intake of 1000 Bq of the preceding isotopes then the milk will have the following activities.Jiří Hála's textbook states that soils vary greatly in their ability to bind radioisotopes, the clay particles and humic acids can alter the distribution of the isotopes between the soil water and the soil.This radioisotope can be released from the nuclear fuel cycle; this is the radioisotope responsible for the majority of the dose experienced by the population as a result of the activities of the nuclear power industry.Discharges from nuclear plants within the nuclear fuel cycle introduce fission products to the environment.The releases from nuclear reprocessing plants tend to be medium to long-lived radioisotopes; this is because the nuclear fuel is allowed to cool for several years before being dissolved in the nitric acid.The releases from nuclear reactor accidents and bomb detonations will contain a greater amount of the short-lived radioisotopes (when the amounts are expressed in activity Bq)).After release into the environment, radioactive materials can reach humans in a range of different routes, and the chemistry of the element usually dictates the most likely route.that cattle only pass a minority of the strontium, caesium, plutonium and americium they ingest to the humans who consume milk and meat.The accident could have been stopped at several stages; first, the last legal owners of the source failed to make arrangements for the source to be stored in a safe and secure place; and second, the scrap metal workers who took it did not recognise the markings which indicated that it was a radioactive object. reported in 2006 details of the uptake of The caesium was found in the leaf veins, in the stem and in the apical leaves.It was found that 12% of the caesium entered the plant, and 20% of the strontium.