The Environmental Protection Agency on Tuesday issued an emergency order to stop the use of a pesticide that can harm fetuses — the agency’s first such move in almost 40 years.

The herbicide, called dimethyl tetrachloroterephthalate (also known as DCPA or Dacthal), is used to control weeds on a variety of crops, including broccoli, onions, kale, Brussels sprouts, cabbage and strawberries.

But when a pregnant woman is exposed to the chemical, it can cause changes to fetal thyroid hormone…