There are beginning to be more requests for the testing of “heavy metals” in the soil. The high cost of food is causing people to plant their own gardens or turn to “community gardens” to raise their own food. With more people looking at organic growing of these foods there is a concern over other elements in the soil that may affect these plants. In the following table is a list of metals, their chemical symbol, the common range and the average concentrations found in soils. If the results of your soil test report levels are near the average concentration, there is normally not a problem. If the results of your test indicate levels that are significantly higher than the average concentration then this should be looked into more deeply. It should be noted that some of these elements are not of major concern, and that testing of some can be very expensive. Contact a local extension agent, county health department, to help provide you with more information on what the results.
Metal Concentrations in the Soil | |||
---|---|---|---|
Element | Symbol | Common Range (ppm or mg/kg) |
Average Concentration (ppm or mg/kg) |
Aluminum | Al | 10,000-300,000 | 71,000 |
Antimony | Sb | 2-10 | not available |
Arsenic | As | 1-50 | 5 |
Barium | Ba | 100-3,000 | 430 |
Beryllium | Be | 0.1-40 | 6 |
Boron | B | 2-100 | 10 |
Bromine | Br | 1-10 | 5 |
Cadmium | Cd | 0.01-0.7 | 0.06 |
Cesium | Cs | 0.3-25 | 6 |
Chlorine | Cl | 20-900 | 100 |
Chromium | Cr | 1-1,000 | 100 |
Cobalt | Co | 1-40 | 8 |
Copper | Cu | 2-100 | 30 |
Fluorine | F | 10-4,000 | 200 |
Gallium | Ga | 0.4-300 | 30 |
Gold | Au | not available | 1 |
Iodine | I | 0.1-40 | 5 |
Lanthanum | La | 1-5,000 | 30 |
Lead | Pb | 2-200 | 10 |
Lithium | Li | 5-200 | 20 |
Magnesium | Mg | 600-6,000 | 5,000 |
Manganese | Mn | 20-3,000 | 600 |
Mercury | Hg | 0.01-0.3 | 0.03 |
Molybdenum | Mo | 0.2-5 | 2 |
Nickel | Ni | 5-500 | 40 |
Radium | Ra | 8 × 10-5 | not available |
Rubidium | Rb | 5-500 | 10 |
Selenium | Se | 0.1-2 | 0.3 |
Silver | Ag | 0.01-5 | 0.05 |
Strontium | Sr | 50-1,000 | 200 |
Thallium | Tl | not available | 5 |
Tin | Sn | 2-200 | 10 |
Tungsten | W | not available | 1 |
Uranium | U | 0.9-9 | 1 |
Vanadium | V | 20-500 | 100 |
Yttrium | Y | 25-250 | 50 |
Zinc | Zn | 100-300 | 50 |
Zirconium | Zr | 60-2,000 | 300 |
Source: USEPA Office of Solid Waste and Emergency Response, Hazardous Waste Land Treatment, SW-874 (April 1983, page 273 |