The organization and daily routine of a wagon train depended on the danger expected from the Native American tribes into whose territory it had traveled, the terrain, and the size of the caravan. Mormon trains, in particular, had a semi military formation.
Side effects. Taken at normal doses, selenium does not usually have side effects. An overdose of selenium may cause bad breath, fever, and nausea, as well as liver, kidney and heart problems and other symptoms. At high enough levels, selenium could cause death.
What Are the Side Effects of Taking Selenium? The upper limit of healthy selenium intake is 400 micrograms. Side effects of too much selenium include brittle hair and nails. However, you would have to consistently consume way more than the upper limit over a long period of time before any signs of toxicity start to show.