An activity involving physical exertion and skill that is governed by a set of rules or customs and often undertaken competitively. b. often sports (used with a sing. verb) Such activities considered as a group: Sports is a good way for children to get exercise.
Rust is Iron Oxide. Hence, any warnings concerning the ingestion of iron may apply. Ingesting too much iron, whether it be via rust, suppliments, or otherwise, can lead to unpleasant symptoms including nausea and vomiting. Long-term side affects such as liver damage can be associated with excessive iron intake.
Because the rust is precipitated as a result of secondary reactions it is porous and absorbent and tends to act as a sort of harmful poultice which encourages further corrosion. For other metals or different environments different types of anodic and cathodic reactions may occur.