Question: What Happens if Someone Drops a Consecrated Host?
Answer: Despite our best efforts, and this is as true in our liturgical celebrations as in all of life, accidents happen. Occasionally at Mass, a host may be dropped or some of the Precious Blood could even be spilled from the chalice, despite the best efforts of the priests, deacons, and extraordinary ministers of holy Communion assisting at the liturgy.
So, when a host is dropped or the Precious Blood is spilled, we can take guidance from the U.S. Bishops’ statement Norms for the Distribution for Holy Communion Under Both Kinds:
All ministers of Holy Communion should show the greatest reverence for the Most Holy Eucharist by their demeanor, their attire, and the manner in which they handle the consecrated bread or wine. Should there be any mishap — as when, for example, the consecrated wine is spilled from the chalice — then the affected “area . . . should be washed with water, and this water should be then poured into the sacrarium.”
According to no. 280 of the General Instruction of the Roman Missal, the general rule is that a dropped host is picked up by the minister distributing Communion and reverently consumed. The minster should be careful to make sure that no other particles from the host remain on the ground. As we see in the instruction from the bishops, the Precious Blood would be absorbed (customarily with a purificator) and the area attentively and reverently washed with water which would then be disposed of properly.