Kathy, thanks for your question.

Using galvanized materials for raised bed vegetable gardening is generally considered safe but, there can be some issues with the zinc coating used on the galvanized material. Iowa State University says that while galvanized steel is generally safe, zinc leaching can occur in acidic soils, which may affect plant health. They recommend using food-grade galvanized steel and implementing barriers like non-toxic liners to minimize soil contact. And some galvanized materials may contain trace amounts of lead and cadmium, which are harmful to both plants and humans.

There are quite a few other options for raised bed materials to consider. For example untreated hardwood planks of black locust, cedar, Osage orange, redwood, or oak make good choices for constructing raised beds. These rot-resistant woods are more expensive but are long-lasting and safe. Composite materials  and masonry materials can also be used to make raised beds.

In general pressure treated woods made with CCA or ACQ and creosote treated woods should be avoided in raised beds used to grow vegetables unless precautions are take.

No matter the material used to construct the raised beds it is recommended to make the sides of the raised beds 8 - 12 inches high to allow for adequate root growth.

For more information on raised beds and materials use to make raised beds see the links below.

Georgia

Penn State