American Notes PHOENIX

Affluent parents who worry about the threat of kidnaping or sexual abuse by the babysitter are discovering that a graver danger to their children may be lurking in their own backyards. So far this year, twelve Phoenix youngsters under age 5 have drowned in residential swimming pools, twice the number for all of 1988. With 22 deaths of young children, Arizona is the No. 1 state in child drownings.

, Early summer heat and a lack of adult supervision are blamed for the rash of accidents. Two brothers, ages 2 and 3, drowned within four minutes when their mother went to answer the telephone. More than 8,000 people showed up recently for a free course in cardiopulmonary resuscitation, or CPR, and requests for pool-fencing estimates have tripled. But authorities stress that parental vigilance is the key to preventing these tragedies. "If you can't answer the doorbell without taking your eyes off the kids," warns Stephen Jensen, assistant to the Phoenix fire chief, "don't answer the door."