Safety

Milorganite^® Safety

Laboratory Technician at MMSD working in the Central Laboratory testing Milorganite

Is Milorganite Safe?

Milorganite is produced with your safety in mind every single day. It complies with all applicable federal and state requirements and can be used with confidence for all of your fertilizing needs, including lawns, trees, shrubs, flowers, and vegetables.

It meets stringent criteria imposed on any fertilizer product for health, safety, and the environment and is more heavily regulated by the United States Environmental Protection Agency (EPA) than synthetic fertilizers.

Milorganite has consistently met the EPA’s Exceptional Quality criteria since 1993, when the guidelines were created.

Is Milorganite Fertilizer Safe to Use?

Daily Testing for EPA and State Standards

Milorganite is analyzed for at least 20 parameters every day to comply with all applicable safety guidelines. Routine analysis is also conducted to test for numerous other pollutants and pathogens. For additional information, you can refer to Milorganite’s Safety Data Sheet.

The Truth About Metals

Metals are not all bad. Some metals are micronutrients and are necessary in small amounts for plants to grow and reproduce, including copper and zinc, which naturally occur in the environment. For a product like Milorganite, federal and state regulations have established limits for metals to protect public health and the environment. Milorganite contains metals at levels found safe by EPA when Milorganite is used as directed.

Metals - EPA Limits & Milorganite Averages

Metals & Micronutrients	EPA Exceptional Quality Limit	2023 Milorganite Avg
Arsenic	41 mg/kg	4.2 mg/kg
Cadmium	39 mg/kg	0.48 mg/kg
Copper*	1,500 mg/kg	220 mg/kg
Lead	300 mg/kg	28 mg/kg
Mercury	17 mg/kg	0.23 mg/kg
Molybdenum*	75 mg/kg	11 mg/kg
Nickel	420 mg/kg	26 mg/kg
Selenium	100 mg/kg	4.8 mg/kg
Zinc*	2,800 mg/kg	440 mg/kg

*Essential micronutrients

Children and Pets

Milorganite is safe for your children and pets when used as directed and stored out of their reach. Milorganite is composed of organic matter and nutrients and contains no added pesticides or herbicides.

Children & Pet Safety

Heat Drying Kills Pathogens

Milorganite is heat-dried in large-scale, bus-sized rotary dryers that operate at 900–1200°F which heats the Milorganite to an internal temperature of 176°F. The extreme heat and dryness kill pathogens. Here’s a video on how Milorganite is produced. You can see the dryers for yourself.

Non-Leaching Phosphorous

Phosphorus in runoff is a significant pollution problem. Excess phosphorus causes algae blooms, fish kills, and odors. Plants, including grass, need phosphorus, as it contributes to important functions such as root development and growth. The phosphorus in Milorganite is slow-release, reducing the risk that phosphorus will leach from soils into surface or groundwater. In contrast, other fertilizers often contain quick-release phosphorus that is more likely to leach.

Micro-impurities: Pharmaceuticals and Personal Care Products

In modern society, it’s inevitable that trace amounts of pharmaceuticals and personal care products will be present in wastewater. Although detectable, concentrations of these compounds are extremely low in Milorganite.

From water reclamation and Milorganite production to harvest and consumption, it’s a long pathway for these micro-impurities to reach humans. The risk they pose to people and the environment is extremely low and is reduced at every step along the way. Milorganite is a leader in investigating the risk caused by these compounds.

One study found that Triclosan, a commonly used anti-bacterial, anti-fungal agent used in a range of products from soap to toothpaste, was detected at very low levels in vegetables fertilized with Milorganite, with corn having the highest concentration. A 154-pound person could eat up to 1,249 lbs of this corn daily without any adverse effect, indicating that the risk of Triclosan exposure from Milorganite is extremely low.

Per- and Poly-fluoroalkyl Substances (PFAS)

Per- and polyfluoroalkyl substances or “PFAS” are a group of more than 9,000 man-made chemicals that are fire, oil, grease, water, and stain resistant and are found in a wide array of consumer and industrial products, including non-stick cookware, food packaging, dental floss, cleaning products, and cosmetics.

The Milwaukee Metropolitan Sewerage District (MMSD) does not use PFAS in the production of Milorganite fertilizer. Instead, wastewater reclamation facilities are passive recipients of PFAS contained in wastewater emanating from residential, commercial, and industrial products. PFAS concentrations in wastewater streams vary significantly depending on local industry and historical firefighting operations at local airports.

Milorganite strongly believes that control of PFAS sources prior to entry into the wastewater stream is the solution to continued PFAS contamination.

PFAS by the Numbers

Products as shown in the bar graph below with typical concentrations.

National and state PFAS regulatory standards for biosolid fertilizers like Milorganite are still forthcoming. Several states have established Perfluorooctane sulfonic acid (PFOS) and Perfluorooctanoic acid (PFOA) concentrations of less than 20 parts per billion (ppb) for biosolids like Milorganite.

Using EPA’s approved testing protocol for PFOA and PFOS, the three most current results for these chemicals in Milorganite products averaged under seven ppb.

By contrast, PFAS has been detected at the following much higher concentrations in various other products:

Dust in an average home has 523 ppb

Lipstick contains 216 ppb to 1,560 ppb

Fast-food packaging is 7,000 to 876,000 ppb

We recognize and share the public’s concern about PFAS and fully support more research into their impacts on public health. For more information, view the U.S. Environmental Protection Agency (EPA) website and PFAS fact sheet.