IF YOU SEE SOMETHING, SAY SOMETHING: Woman suspected of tainting OJ at Starbucks said to be trained chemist.

A customer reported seeing the woman remove two bottles of orange juice from her purse and place them in a refrigerated display case at the store, the Mercury News reported.

When the customer alerted store staff the woman fled.

After examining the bottles and detecting what they described as a “toxic smell,” store employees called 911.

Police tracked 50-year-old Ramineh Behbehanian to her home about five miles away after a witness provided her license plate number. She was arrested on suspicion of felony poisoning.

Tests revealed she had mixed rubbing alcohol with the juice, police said. Investigators said they did not have a motive.

It was a “lethal” quantity, reportedly.