He is now totally disabled, with a wide variety of symptoms, and he has won a major lawsuit against the manufacturers of CCA treated wood. The eating surface of a picnic table should never be made of treated lumber, and I have some serious reservations about using CCA treated wood for such things as play ground equipment and decks where children are in very close contact with it. A fairly recent development in wood treatment is Tim-Bor, manufactured by U.S. Borax. Its only drawback is the fact that it is water soluble, so it can't be used in contact with the ground. It is currently being used successfully on log cabins, and in such an application, it needs a clear finish to prevent it from being leeched from the surface by rain.
Plans are underway to develop a borate based product that can be exposed to the weather.
This product should find its way into lumber yards within the next couple of years. In the meantime, treated wood can be avoided completely, by using an insect resistant species like redwood or cedar. These make beautiful picnic tables and decks. Many chemically sensitive people are bothered by the aroma of cedar, but I have found redwood to be very well tolerated. Since these woods are more costly than treated lumber, they are not stocked by all lumber yards.