Code of Maine Rules
01 - DEPARTMENT OF AGRICULTURE, CONSERVATION AND FORESTRY
001 - AGRICULTURE - GENERAL
Chapter 350 - REGULATIONS UNDER THE MAINE COMMERCIAL FERTILIZER LAW
Section 001-350-8 - ADULTERATED MATERIALS
Current through 2024-38, September 18, 2024
1. Fertilizers containing guaranteed amounts of phosphates and/or micronutrients shall be deemed to be adulterated when they contain metals in amounts greater than the levels of metals established by the following table1:
| Metals | ppm per 1% P2O5 | ppm per 1% Micronutrients3 |
| 1. Arsenic | 13 | 112 |
| 2. Cadmium | 10 | 83 |
| 3. Cobalt | 136 | 2,2284 |
| 4. Lead | 61 | 463 |
| 5. Mercury | 1 | 6 |
| 6. Molybdenum | 42 | 3004 |
| 7. Nickel | 250 | 1,900 |
| 8. Selenium | 26 | 180 |
| 9. Zinc | 420 | 2,9004 |
To use the Table:
Multiply the percent guaranteed P2O5 or sum of the guaranteed percentages of all micronutrients (Iron, Manganese, Zinc, etc.) in each product by the value in the appropriate column in the Table to obtain the maximum allowable concentration (ppm) of these metals. The minimum value for P2O5 utilized as a multiplier shall be 6.0. The minimum value for micronutrients utilized as a multiplier shall be 1. If a product contains both P2O5 and micronutrients multiply the Guaranteed percent P2O5 by the value in the appropriate column and multiply the sum of the guaranteed percentages of the micronutrients by the value in the appropriate column. Utilize the higher of the two resulting values as the maximum allowable concentrations.
1. Biosolids, and all compost products4, shall be deemed to be adulterated when they exceed the levels of metals permitted by the United States Environmental Protection Agency Code of Federal Regulations, 40 CFR Part 503 or 06 - 096 CMR 419. Dried biosolids and manure, as well as manipulated manure products either separately or in combination, shall also be deemed adulterated when they exceed the levels of metal permitted by the United States Environmental Protection Agency Code of Federal Regulations, 40 CFR Part 503 or 06 - 096 CMR 419. Hazardous waste derived fertilizers (as defined by EPA) shall be deemed to be adulterated when they exceed the levels of metals permitted by the United States Environmental Protection Agency Code of Federal Regulations, 40 CFR Parts 261, 266 and 268.
Footnotes:
1 Woltering, Daniel M. 2004. Health Risk Assessment for Metals in Inorganic Fertilizers: Development and Use in Risk Management. In Environmental Impact of Fertilizer on Soil and Water. Hall, William L. Jr. and Wayne P. Robarge, Editors. American Chemical Society Symposium Series No. 872. p124-147.
2 These guidelines are not intended to be used to evaluate horticultural growing media claiming nutrients but may be applied to the sources of the nutrients added to the growing media.
3 Micronutrients (also called minor elements) are essential for both plant growth and development and are added to certain fertilizers to improve crop production and/or quality. These micronutrients are defined by AAPFCO's Official Fertilizer Term, T-9.
4 Only applies when not guaranteed.
5 Includes all compost products separately or in combination with biosolids, manure or manipulated manure, even those registered as fertilizers (making nutrient claims).(Official 2003)
