First, in order to answer this question I need to know the type of wood and the work previously done on it.
- Most types of wood repurpose well for this use but if there were toxins used on it before, they could leech out.
- I've personally only had that happen when the wood was previously used as a storage vessel.
Because this table will come into contact with water, you should know that woods vary greatly in stability when wet.
- Maple and teak, when the wood is in a thick cut or slab, stand up quite well.
- Cherry will stain and discolor but otherwise is fairly stable.
- Teak is very sturdy but as a chopping block, might dull your knives because of the silica content.
In general I would prefer to use wood from a fruit or edible nut tree such asmaple or olive.
- I would want to know what it had been used for before so as to determine if there were any toxins hiding under the surface.
- Lastly, repurposing wood has to be done carefully to avoid introducing harmful insects into your home. Check the wood carefully for holes, tunnels and rot. If you can, kiln dry it.
- Then oil it with a food approved wood oil.