The maximum allowable level for halogenated organic compounds is 1%.

When the Fertilizer Regulation Act was adopted in 1998, it included standards for the maximum acceptable annual addition of metals to soils. These standards were adopted as a result of growing concerns over metals in fertilizers that are manufactured from hazardous waste. The Washington Standards for Metals, WAC 16-200-7064, set a maximum allowable yearly addition of the following metals to Washington soils: Arsenic, Cadmium, Cobalt, Mercury, Molybdenum, Nickel, Lead, Selenium, and Zinc (see below).

Beginning with the July 1998 registration cycle, the Washington State Department of Agriculture (WSDA) has applied the Washington Standards for Metals to all fertilizer applications for registration in the annual registration process. The WSDA database compiling the results of that registration process for each fertilizer product registered for distribution or sale in the state of Washington is located at WSDA Database.

The Washington Standards for Metals are applied to fertilizers by (1) analyzing the fertilizer to determine the amount of each of the nine metals of concern in the fertilizer product, and (2) calculating the amount of metal that would be added to the soil by using the fertilizer at the maximum application rate for that product. The maximum application rate (which is usually taken directly from the product label) is multiplied by the amount of a particular metal in a fertilizer to estimate the total amount of that metal that will be added to the soil through use of the fertilizer. That figure may not exceed the maximum allowable level for that metal in the Washington Standards for Metals (see list below).

Example: The metals analysis for Lovely Lawn Weed and Feed indicates this product contains 5 parts per million cadmium. The label on Lovely Lawn Weed and Feed states that this product should be applied at a rate of 1 lb./250 sq. ft. and at a maximum of three applications per year. This calculates out to be 0.0026 pounds of cadmium/acre/year compared to a maximum allowable level of 0.079 pounds/acre/year for cadmium. Lovely Lawn Weed and Feed is well under the maximum allowable level for cadmium set by the Washington Standards for Metals.