Wood

Wood is inert against food and does not leach. The specific worry it usually arrives with - that wood is less hygienic than plastic because it is porous - is the one the evidence contradicts. Dean Cliver's food safety lab at UC Davis found that E. coli, Salmonella and Listeria applied to wooden surfaces were not recoverable a short time later, that bacteria drawn below the surface did not multiply and gradually died, and that used, heavily knife-scarred wood behaved essentially like new wood - while knife-scarred plastic was impossible to clean and disinfect by hand, especially with food residue such as chicken fat present. The effect held across more than ten hardwood species with no meaningful difference between them. Regulators reflect this: FDA Food Code 4-101.17 bars wood as a food-contact surface in general but specifically permits hard maple or equivalently hard, close-grained wood for cutting boards, butcher blocks, rolling pins, salad bowls and chopsticks. Two real caveats remain, and both are about what was added to the wood rather than the wood itself. Board glues are typically sold as compliant with 21 CFR 175.105, the FDA rule for adhesives in food packaging - an indirect-contact standard being applied to a surface you cut on, which is a weaker guarantee than it sounds. For finishes, food-grade white mineral oil has its own direct food-additive listing at 21 CFR 172.878; a fully cured polyurethane or varnish film is not the hazard it is often made out to be, but it chips into food, cannot be spot-repaired, and seals the wood so it can no longer dry out or be renewed.

Heat is not a leaching question for wood - there is no polymer to soften and nothing to migrate - it is a structural one. The dishwasher is what kills wooden boards and spoons: prolonged soaking plus a hot dry cycle swells and shrinks the fibers unevenly, raises the grain, and stresses glue joints until they open. A wooden spoon resting in a simmering pot is fine; a wooden handle left against a hot pan scorches and eventually chars rather than melting.

Look at the edges and the end. A one-piece board shows continuous grain wrapping around all four sides; a laminated board shows repeating strips with visible glue lines. End grain reads as a checkerboard of pore ends - knives part the fibers rather than slice across them, so the surface closes back up and shows scarring less, at the cost of more weight and more re-oiling. Edge grain shows long parallel lines and is the cheaper, lighter, more stable build. Bamboo is the usual lookalike: it has no growth rings and no visible pores, showing flat strips with occasional darker node lines instead. If a listing says only wood, or only acacia, ask the brand three things - the species, what adhesive laminates it, and what the factory finish is. A brand that answers with a species, a glue type and an oil knows its own product; a brand that cannot name the glue is reselling boards from a contract factory.

Hand wash with soap and hot water, rinse, and stand it on edge so both faces dry at the same rate - a board left flat on a wet counter cups toward the damp side. Re-oil when water stops beading and the surface goes pale and dry, which for a board in regular use means roughly monthly at first and a few times a year after that. What actually destroys wooden kitchen items is the dishwasher, standing water, and long soaks; deep cracks and an opened glue line are the end of one. A well-kept hard maple board (Janka hardness around 1450 lbf) outlasts decades of use, and a scarred surface can be sanded flat and re-oiled back to new - something no plastic board can do.

Untreated wood composts and burns cleanly. An oiled, glued board still biodegrades, just more slowly, and the glue line is a small fraction of its mass. Wood is not accepted in any curbside recycling stream, so a dead board is firewood, garden mulch, or landfill where it will break down rather than persist. Do not burn boards finished with polyurethane or varnish indoors.