Margaret Zeidman, age 13, of Bowling Green, Ohio, for her question:

WHAT IS TUNG OIL?

Tung oil is an oil that comes from the seed kernels of the tung tree. The tung tree originally grew in the Far East, chiefly in China.

The tung tree has also been successfully grown in the southern part of the United States. Oil from the tree is also called China wood oil, Japanese wood oil or simply wood oil.

Tung oil ranks as one of the most powerful drying agents. The oil resists acids, alkalis and alcohols.

Tung oil is widely used in paints, lacquers, varnishes and printing inks. Paints containing tung oil help seal the underwater surfaces of swimming pools, dams, piers and boats.

Varnishes made with tung oil help insulate wire and metallic surfaces.

Tung oil helps some printing inks stick to metal surfaces such as bottle caps.

Because of its relatively high cost, tung oil is sometimes replaced with epoxy resins and other synthetics.