But there has been a lot of people worrying about whether treated wood is safe to use in the garden. Lettuce spinach and mustard greens tend to move metals into the leaves.
Before 2006 the answer would have certainly been no.
Is acq treated wood safe for vegetable gardens. You Can Use Treated Lumber for Raised Bed Gardens Scientific evidence backs up the claim that it is fine to use modern treated lumber in raised bed gardens. CCA treated wood is no longer available for residential use as of 2004. The relatively new chemical treatment ACQ alkaline copper quaternary is safe to use in food gardens.
It is considered to be low in toxicity. Wood treated with boric acid aka. And there is an excellent alternative that I like a lot.
From what Ive seen the consensus is that the chemicals do leach out of the wood into the soil and are uptaken by the plants in very small amounts. My wife and I were advised to use ACQ treated timbers when considering cedar alternatives for raised vegetable gardens. Before 2003 a dangerous chemical chromated copper arsenate CCA was used to treat wood.
This type of lumber was known as CCA. He stated in a bulletin titled Treated Wood in Raised Bed Gardening Scientific evidence and data have shown that using pressure treated wood for raised bed or box gardening is safe to adults and children in terms of the plants grown and used in these containers He further explains All chemicals in consumer products have a toxicity and most are very low so they are not a problem especially those regulated by the federal government. The safety of pressure treated lumber for raised bed gardens has been examined by several researchers.
While there is scientific consensus that it is safe to use for vegetablegarden beds the information below explains what chemicals are used in Viance ground contact treated wood for residential use and the results of numerous scientific studies. So we purchased the ACQ timbers. Studies have shown that arsenic from wood treated with CCA leaches into the soil and that copper although much less toxic leaches from ACQ and copper boron azole CBA a variant of CA-B.
Some of the copper may leach over time from the lumber but the risk to human health is considered to be low. You can use it to construct raised garden frames. Sally Brown a research assistant professor of soils at the University of Washington knows her way around both food and metals.
Is It Safe to Use Treated Wood For Vegetable Gardens. I would have thought cedar a good choice but was told that it would deteriorate within a year given direct soil contact. But now AQC is used and this is much safer for use in your vegetable garden.
Manufacturers of pressure-treated wood with micronized copper quaternary claim that their lumber wont leach any copper into the soil and therefore its safe for all uses including making garden beds. Yes the modern pressure treated wood is safe. However I havent seen any research that suggests the level of the chemicals is significant enough to be of concern for human health.
ACQ treated lumber is not expected to have adverse effects on the health of adults and children according to the published Human and Ecological Risk Assessment 2007. CCA-treated wood containing copper chromium and arsenic is no longer available for residential use as of 2004. Most metals remain in the roots with the exception of leafy green vegetables.
Soil experts disagree on using copper-treated wood products in a vegetable garden. Alkaline Copper Quaternary ACQ is currently the most widely available type of wood preservative for residential use. Its probably a big improvement over arsenic treated wood whose health effects were clearly dire.
Now the CSIRO say the potential ingestion of arsenic from CCA treated timber is within tolerable limits and it can be used around vegie gardens with some precautions such as painting the inside of the garden bed with an exterior grade paint or lining it with plastic to prevent the timber making direct contact with the soil. Other studies have shown that copper can leach from the wood but we need more research on this to know if it has a toxic effect on the environment. AWPA recommends use of UC4A or higher labeled treated lumber for horticultural uses.
But its highly corrosive to certain metals leading me to worry about its effects on soil life. Some see no serious risk for humans in using them in a vegetable garden the amount of copper released being minimal and copper being considered essentially nontoxic unless present at extremely high levels. These days there are plenty of other materials in lieu of wood treated with suspect chemicals like arsenic to make raised vegetable gardens including Microshade treated wooden sleepers that are deemed safe for vegetable gardens and childrens play areas but are still pest resistant sustainable and reasonably priced.
It does not contain arsenic but it does contain copper. Alkaline copper quaternary ACQ Copper is considered less toxic compared to arsenic. In 2002 the wood preserving industry voluntarily decided to phase out the use of arsenic and chromium for general use by the public.
The Environmental Protection Agency EPA abolished its usage for being a human carcinogen. Results showed that ACQ-treated wood is non-toxic to skin as well as any normal oral exposure. CA treated lumber is expected to have a similar toxicity risk to ACQ treated lumber.
Treated Wood Safety of ACQ Q.