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I have a raised garden bed using wood logs that have 'UFP Treated' tags at the end. I am using my raised bed for growing vegetables.

  • What does 'UFP Treated' mean?
  • Are these board safe to continue to use it for my vegetable garden bed?
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UFP Treated means that the wood is pressure treated with chromated copper arsenate (CCA) to make it less susceptible to rot. This technique comes from building boats, piers, carports, ... anything that is exposed to the elements and has been around for quite some time.

Opinions as to the CCA being poisonous in planting application such as yours vary greatly and there are researches showing (presumably legitimate) data in any direction. Articles that i read recently are this, that and that. I based my opinion mostly on them which lead me to build a planter for my (very nice and likable) grandmother using treated wood.

One thing that you could do is treat the "treated wood" further with some food safe, oil based finish as this will seal the arsenic to some degree. You'd probably touch that finish up every couple years, the frequency being dependent on how much elemental exposure your planter gets. Here is a quite interesting thread to really safe finishes :).

  • I would think that "touching up" the finish on the dirt contact side of the planter bed might be rather difficult. – FreeMan May 20 '16 at 19:32
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In the United States, since 2003, the availability of CCA pressure treated wood has been scant. EPA does not allow its use in residential applications, so it will be hard to find at your local lumber retailer, be it big box or small yard.

That being said, pressure treated products are readily available but with less threatening EPA approved chemicals. The "UFP Treated" tag should have specific information on its reverse side.

If the tag doesn't say CCA or Chromatic Copper Arsenate, you are good to go with the bed that you have made.

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I wanted to start by quoting an MSDS from a supplier of UFP treated wood

Ecotoxicity: The product is not expected to leach harmful amounts of preservative into the environment; however, some preservative may migrate into soil and water. The wood preservatives in this product contain insecticides and fungicides, which when released into the environment at high enough concentrations, are expected to adversely affect or destroy contaminated plants. They may be harmful or fatal to wildlife. Toxicological and ecotoxicity testing have not been performed on this product. Environmental fate information is not available.

Most of the risk that you will read in that document pertains to the treated dust and the wood dust in itself.

The snippet above basically admits that there in nothing conclusive. Other answers refer to this but there is still some trepidation and potentially information to back that up from other sources. The MSDS does talk about the presence of high concentrations and that it can cause issues with plants. If you weren't going to be eating any of the plants in this bed the I would say go for it.

While the risk is arguably low there is still a potential risk compared to not using treated wood in a home garden. If you are going to be eating the plants and vegetables from this bed I would err on the side of caution and consider rot resistant woods like cedar instead.

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