The top five reasons your garden may have unwanted contaminants.
A nanoparticle size as a nutrient is required in order for it to be bioavailable, for plant uptake. This nutrient must be in a non-toxic form or proper valence for the plant’s absorption, much like the food, for humans. Minerals such as chromium must be in the trivalent form for proper nutritional value. The hexavalent forms of chromium are highly toxic. Nanoparticles of lead can easily absorb into the plant. The lead is easily transferred to humans when consuming the plant, through our digestive system. Lead from smelting operations, zinc mining, fertilizer impurities and leaded gas exhaust have left their mark on soil, around the world. In years to come, I believe fluoride contamination on our lawns and gardens will be of great concern, as we notice the effects they have on human health, as concentrations increase.
The soils testing performed by most of our universities and the extension offices has not changed over the years. Protocol for soil testing is for standard NPK and pH tests. In addition they may take a grab or composite sample off the field to be tested. They would then send the sample to the lab; the lab chemist digests the sample in an acid solution, and then a spectrum analysis is done to determine the metal content. This method of testing has nothing to do with the bioavailable minerals that are in the soil. The test is only capable of determining the makeup of the soil. I have found that the only proper method of testing for bioavailability of minerals in the soil is to perform plant tissue tests to see what the plant has available in the proper size to utilize. The main problem with the plant tissue test is that different plants varieties uptake different amounts and types of minerals. To address this, the proper way to sample the field would be to take clippings from all plants including the weeds, then dehydrate them, mill them into a powder and submit the powder as a composite for that field.
The plant tissue testing provides me with the tools I need to ensure that our product’s delivery of the quantity and variety of minerals, as food, are at a beneficial level. I have found only one lab, certified and capable of performing these tests with consistency and accuracy. I do not have a vested interest in this lab, but I could not perform my research without their support. Activation laboratories in Canada utilize an ICP mass spec and also a high-resolution ICP mass spec for their testing. This lab is able to perform the test on a green leaf or on ashed samples.
I strongly recommend sampling your garden before investing in soil amendments, or adding fertilizers.
The top five reasons your garden may have unwanted contaminants:
- A gardener may have applied compost from a public composting site that mixes grass clippings and organic products, which have been exposed to pesticides and lawn fertilizers.
- Lawn fertilizers were mistakenly placed on the garden instead of garden-tested fertilizer.
- The water supply has sodium fluoride in its system. Two ppm of sodium fluoride may deposit an estimated 2 g fluoride annually on a 20 x 20 garden. Fluoride is easily absorbed in most garden vegetables.
- If your garden is within close proximity to a major road or highway, which was in existence during the time of leaded gasoline.
- There may be a background mineral that occurs commonly in your region. In areas where there has been zinc or lead mining it is not uncommon to see higher levels of minerals within miles of the mining operation. Ore deposits occur in regions, not necessarily where the mine was located.
Once you have tested and have the results, I recommend anything below 1 ppm, or 1000 ppb are acceptable for Lead, Mercury and Arsenic. Mercury and Arsenic can be reduced by converting them to alcohol through a composting process. This is discussed in Mr. Riddell’s book “The Complete Book of Composting”. It is a great reference source for most composting issues.
If you find your numbers are completely unacceptable you may contact us. We have tested a composting company’s product and find it very acceptable and within limits, as a replacement topsoil. This topsoil company will be blending our soil amendments and we will be selling topsoil product in bulk, or in bags. Look for these products by the spring of 2017. We will have the analytical test results on these products.
If you have any questions or comments, I would love to hear from you.
Robert J. Van Risseghem