Say no to Bleach
Chlorine bleach is a no-no on wood. It is an oxidizing agent and harmful to exposed wood fibers. If bleach is neccessary to lighten wood, oxalic acid is the preferred chemical. It is the active agent in many teak cleaners as well as in Zud and Barkeepers' Friend, two common househld cleaners that should be kept on board. As a reducing agent, oxalic acid is also excellent for removing tarnish and rust stains. In any event, I'd avoid using any bleaching agent on finished wood as it will lighten the color anywhere it can penetrate the finish and you will end up with an uneven apearance. On areas sealed with oil, it is fine as long as you apply it to the entire surface. Check the label for use on finished wood for products such as Lysol which kill mold and mildew. I think they are ok for paint and most modern marine varnish can be treated as a painted surface.
