wood chips will work well if used in the little steel noxes designed for them. I helps them burn more slowly. Also, soak the hcips in water for an hour or more to make them last longer.
Aas far as the creosote problem, a little wash with water and vinegar will help remove that. If there are any fallen branches in your area from nut or fruit trees, or maple, birch or white oak, or tag alder, those make amazing smoking woods. Each has its own distinctive flavor and contains no chmicals.
Aand about the pharmeldihyde, that's spelle formaldihyde and is indeed a preservitive, and a caarcinogen, and a resperatory irritant, etc. It is a powerful chemical that occurs naturally in nature, but is often used in laboratory settings to inhibit enzimatic and biological destruction of animal and insect specimens. It is also found in some adhesives as a solven that outgasses into living spaces and is a major contributor to indoor pollution. It's generally considered to be nasty stuff. I wouldn't want it on my food.
Remember, all food flavorings must be used in moderation as they can quickly mask the natural flavors you wish to enhance. You can always add more, but once it's in the food, it's nearly impossible to remove, and that includes smoke. start with a little, and add more as needed.
Seeeeeya; Goodweed of the North
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