Editor's response: Our article mentioned linseed oil, rather than boiled linseed oil, as a finish for wooden toys, but we should also have taken the space to explain further. Linseed oil is produced from flax seed and provides deep protection against water and dirt, while allowing the wood to breathe naturally; it can be used as a pre-treatment for surfaces that are to be waxed. However, pure lin seed oil leaves a somewhat sticky surface and dries slowly. When heated, it gets thicker and dries faster. That sort of lin seed oil is sometimes available as a natural wood finish and will be labeled as "polymerized" or "heated." However, most hardware store linseed oil products labeled as "boiled linseed oil" contain petroleum-based solvents and metallic dryers. As this reader suggests, its use is somewhat controversial among woodworkers. For instance, Bob Flexner, a contributing editor to Popular Woodworking magazine and the author of the book Understanding Wood Finishes (Rodale Press), feels that either finish should be safe for children to chew on, once it has fully cured for around 30 days. But to err on the side of care, it isn't necessary to use hardware store grade boiled linseed oil. The Canadian natural wood finish company Eco-House Inc. sells a variety of environmentally-sound, healthy finishes that include linseed oil. In the U.S., Tried and True produces a line of linseed oil-based organic finishes that are also safe for toys.