Is it safe to grow plants in PVC pipe?
When a person decides to build or even purchase a hydroponic system one of the most common and easiest materials to work with is PVC pipe which stands for polyvinyl chloride. People may worry about the safety of using such materials because vinyl chloride has been shown to have serious toxicity in some circumstances. By using PVC pipe to build a hydroponic system some people worry that the vinyl chloride levels may be dangerously unhealthy.
What do we believe?
Like many DIY hydroponic gardeners we have chosen and continue to use PVC to grow a steady supply of nutritious and lush greenery that we ourselves eat. We can not and do not make the claim that PVC is 100% safe no questions asked but we did decide to go ahead and have some lab testing done on our hydroponic nutrient water that had been circulating through our PVC pipe hydroponic system ( plans for that build available here: SFT Build 1 plans ). The water that we had tested was continuously run through our PVC hydro setup for almost 3 weeks before we had it tested. We felt that 3 weeks was a good amount of time to test because many hydroponic gardeners recommend changing your nutrient solution before that amount of time has passed. We found a lab that could test for vinyl chloride in water and sent the samples off via next day delivery.
The results for vinyl chloride content in nutrient solution.
The long results can be found here:
The short story of the lab test results can be found on the last page of the lab test PDF shown above. The test that they did was comparing EPA allowable amounts and the minimum detection level was 0.001 ppm. The lab test listed vinyl chloride as “ND” for Not Detected. So basically what this test said is that not only was the vinyl chloride level in the nutrient solution meeting the EPA safe levels, it was not even detected at any significant amount in our test samples.
We are just the messenger, no guarantees being made.
This is just one lab test result and it provided us with information that we found made us even more pleased with our choice of construction materials that we used in our DIY hydroponic system. We have an indoor system and it may be possible that an outdoors PVC system may cause different results. We can’t be sure and we are not claiming PVC is 100% safe but we personally feel it is safe and will use it for some of our own personal food supply as we continue to grow in the system. Please look over the data and do your own research before you make your own decisions.
Extra info from the lab tests.
As a side note to add depth for anyone viewing the complete test result PDF, we were using tap water (which explains the hardness) with General Hydroponics MaxiGro dry fertilizer. We also added a small dose of SEA-90 trace mineral supplement. We had heard whispers that SEA-90 may contain arsenic but according to these results, no arsenic was found which is always a welcome result. The conductivity of the solution at the time of test was not overly concentrated and was somewhere around 2.5 EC as we were growing lettuce at the time. Hopefully you have found this information useful, feel free to let us know your thoughts and suggestions.
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