People have asked me why I prefer to make wands from locally sourced and naturally-aged wood. They are consistently amazed when I tell them that most commercially available lumber is sprayed with chemicals and that these chemicals then soak into the wood and become permanent. Surprised? I was also. The next time you see product that is intended for constant handling, food preparation, or even might end up in someone’s mouth, think about the following.
Trees transport water and nutrients up from the ground to its leaves and after it is cut the wood’s endgrain is like a sponge. Any chemical that comes in contact with it travels throughout the wood. All lumber,regardless of its origin, has been cut down and transported, put through a sawmill, and has been dried in a kiln. All the steps of this process are capable of introducing chemicals to the wood.
To combat "blade binding" and keep the sawblades sharp, sawmill operators must constantly keep the blades coated with liquid lubricant, using a sporadic spray-on or continuous drip method to keep the sawblade coated while the wood is being cut. A variety of chemicals are commonly used as a lubricant, including diesel oil, paint thinner and kerosene. Trace amounts of these chemicals can be found on all surfaces of each piece of lumber that has been through the saw.
Another chemical that finds its way into dimensional lumber is polyethylene glycol(PEG-1000). In recent years, a process known as "dry kilning" has become the industry standard for drying lumber, as it enables much faster removal of the natural liquids contained in the tree. Dry kilning allows much more efficient processing of dimensional lumber, but it can cause excessive shrinkage and cracking of the wood: to prevent this, the green logs are soaked in a solution of PEG-1000, which infiltrates deep into the wood fiber and"bulks" the wood so it won't shrink or crack in the kilns.
Another source of chemical content in dimensional lumber is the use of fungicides. Prior to storage of green lumber, especially in wet or humid locales, chemicals may be applied to prevent growth of fungi which stain wood blue or black, a phenomenon known as "sapstain." Fungicides maybe applied in the production line (usually by spraying) or after the lumber is bundled (usually in dip tanks). Chemicals used include didecyldimethyl ammoniumchloride, 3-iodo-2-propynyl butyl carbamate, azaconazole, borax and2-(thiocyanomethylthio) benzthiazole.
Once out of the kiln, lumber is stacked in bunches separated by wood slats called"stickers". Over time, these stickers can cause discoloration of the wood, resulting in off-color stripes across the grain known in the industry as"sticker stain". Affected lumber is sometimes treated with "wood wash", a solution of oxalic acid, which bleaches out the stains. In weak solution, oxalic acid is commercially used as a rust-remover.
After reading these excerpts, think about what happens when a wooden spoon made from these treated lumbers gets used in a pot of soup, or when cutting produce on a cutting board made out of this material? What about wooden blocks? We worry about lead in paint and additives to dog food, but I never thought of the wood I come in contact with on a daily basis. I've been looking at product descriptions for multiple wooden products, from wooden spoons, cutting boards, and teething rings almost none of them mention where the wood comes from or if it was treated with any chemicals. Some mention the finish as being safe but it's not just a question of finishes.
It’s scary to think of the chemicals you are exposed to unknowingly. The wood I use to create my products is stored in a stable environment (so I don’t have to worry about fungi), and is kept in storage from months to years to allow it to naturally dry. If I use salvaged lumber I make sure to state that in the description. I mill in small batches so I don’t have to worry about my saw overheating. As a conscientious craftsman and father, I believe properly preparing the base materials for my product is important. These extra steps are not something you can see or feel, but hopefully it makes a difference.
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