Warnings about Tanalised Wood/timber
The preservation of timber/wood (tanalising) used to be carried out using a mixture of salts of copper sulphate, potassium dichromate and arsenic pentoxide.
The timber was pressure injected with the preservation liquid in large pressure cylinders, after which it was stacked in the yard while still wet with preservation chemicals. It was not sold till completely dry to reduce contamination.
This was fine in dry conditions, but in the wet, the chemicals could leach out, and the arsenic is transferred to the hands simply from touching the timber.
Children, in particular, are prone to use their hands for eating without washing them first, and can get arsenic poisoning as a result. Food plants grown near tanalised decking can accumulate sufficient chromium to cause symptoms of heavy metal poisoning in anyone eating the produce.
A family in the Antipodes (Australasia) used offcuts of tanalised timber on their barbeque. The cooked meat killed their dog and resulted in the prolonged hospitalisation of the entire family.
Recommendations include avoiding drilling or sawing or use a dust mask if this is unavoidable. Wash thoroughly after touching tanalised timber, and avoid use where people are likely to come into direct contact with the treated timber.
Arsenic has been banned for tanalising in Europe since 2006, although the current tanalising process has been found to be less effective without the arsenic content. The replacement process - Tanalised E - uses copper and triazole biocides - an organic anti-fungal treatment commonly used to protect food crops.
NEVER burn any kind of tanalised timber such as old painted timber or boards, which contain formaldehyde resins (i.e. most plywoods, chipboard, and MDF). Tanalised E may be burned in approved industrial incinerators only, but should not be burned in open fires or home wood burners.
Recycled Plastic Planks and Profiles do not rot and/or leach anything into the soil and are safer therefore than tanalised wood. Kedel's recycled plastic materials are resistant to most chemicals and are safe to use in all agricultural applications or near children, animals, fish etc. without fear of toxicity or pollution. Technical specification available on request.
Click below to watch our Spey Bench Video to get a sense of what Recycled Plastic could offer you: