Fertilizers containing phosphorus are a major source of groundwater contamination and radiation exposure during lawn maintenance.
The most common method for making fertilizer, that contains phosphorous, leaves behind a waste called phosphogypsum, which emits radon, a radioactive gas. It also contains uranium and radium, which are radioactive elements.
Phosphorous is an essential nutrient for plants and a common ingredient in many fertilizers. However, the processing of phosphate rock to make phosphate-based fertilizer may leave radium (Ra-226) in the end product. The levels of Ra-226 vary depending upon the type of fertilizer blend and the origin of the phosphate rock.
Starter fertilizer can contain higher phosphorus levels.