Question

Nancy bought two beautiful hand-painted platters during a recent trip to mexico. she should have these dishes tested for which contaminant before using them to serve food

Answer 1

She should have these dishes tested for lead before using them to serve food.
The person who hand-painted these dishes may have used lead paint, which is a type of paint that contains lead, which is a common contaminant. If she doesn't want to get poisoned by lead, she should check whether these dishes are contaminated before eating from them.