Is it ok to use pressure-treated lumber on raised garden beds?

Photo by Rusty Clark. Creative Common license.

Pressure-treated lumber is extremely popular for outdoor applications. It lasts for decades without rotting and can be placed directly in contact with the ground. A frequent question that arises is whether or not it is acceptable to construct raised vegetable garden beds out of this material.

Before 2003, most treated lumber contained high levels or arsenic, which was proven by the EPA to slowly diffuse into the surrounding soil making it toxic. Since then alternative compounds have been used and treated lumber is supposedly safer.

There is debate as to whether or not the chemicals in the "new" treated wood such as copper derivatives can leach into the soil and end up on the dinner table. Studies have been conducted with mixed results on this matter.

Personally, I would never use treated lumber to construct garden beds. Redwood looks much nicer and also has similar longevity. The cost is only slightly higher, and you don't have to worry about the risk of consuming the fungicides in treated lumber that may end up in the soil. It should be noted that in many regions the use of treated lumber is banned for those seeking organic certifications.

Why risk your health for a product that doesn't look as nice? There are viable alternatives to redwood which I will cover later, however using treated lumber on vegetable beds is a bad idea in my opinion.