Effects of fluoride
The fluoride content of tea depends directly on the fluoride content of the soil in which it is grown; tea plants absorbs this element at a greater rate than other plants. Care in the choice of the location where the plant is grown may reduce the risk.
Effects associated with caffeine
Milk binds catechins, most notably EGCG. Milk also binds tannin, rendering it harmless, which helps to exemplify the effect on tea's constituent parts (i.e. EGCG binding).
Effect of citrus on tea