Puerto Rico has adopted one of the world's toughest legal limits for drunk driving by young adults.
Gov. Luis Fortuno signed legislation Tuesday that lowers the blood alcohol limit for drivers ages 18 to 20 to .02 percent from the standard .08 percent that applies to all other drivers on the U.S. island.
Mothers Against Drunk Driving has said the .02 percent standard is lower than any U.S. state. Sweden has had .02 percent limit for all drivers since 1990.
Some senators criticized the measure, saying the island instead should have raised legal drinking age to 21 from 18 as a way to curb drunk driving.