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.
But beware: selenium also seems to increase the risk of non-melanoma skin cancer. Among healthy people in the U.S., selenium deficiencies are uncommon. But some health conditions -- such as HIV, Crohn's disease, and others -- are associated with low selenium levels. People who are fed intravenously are also at risk for low selenium. Doctors sometimes suggest that people with these conditions use selenium supplements.