What is a Polyacrylamide?

Polyacrylamide (PAM) is a long synthetic polymer that can be tailored to carry a specific charge depending on the application it's being used in. In many cases, these polymers are designed to attract small particles and form clusters of particles that will eventually be heavy enough to settle at the bottom surface, a process called flocculation. This is a very common process used in many other industries like waste management, oil and gas, and mining and mineral processing just to name a few. You can think of it as a chemical filter that separates a liquid into its desired and undesired parts.

There are a growing number of polymer products on the market today. You may be familiar with brand names like PitMax+ or Triune. Before you try them, it's good to know more about how they're supposed to work, and what the risks involved.

The Claims of PAM Products

An ASABE report (Solid-Liquid Separation of Flushed Swine Manure with PAM) claims the following for PAM's use in livestock manure:

• Effective Solid-Liquid Separation: PAM excels at reducing suspended solids in flushed manure, achieving up to 95% removal of total suspended solids and volatile suspended solids when paired with screening. This reduces the volume of liquid waste, making for less liquid to handle and store.
• Nutrient Load Reduction: By capturing up to 85% of organic nitrogen and up to 92% of phosphorus, PAM lowers the nutrient content in the liquid fraction, reducing the risk of nutrient runoff during land application. This can help producers comply with environmental regulations.
• Cost-Effectiveness for High-Strength Manure: For manure with 2–2.5% total solids, PAM can work, with chemical costs estimated at $1.27–$1.37 per finished pig, offering a practical solution for operations with concentrated waste.

These claims make PAM an option for producers focused on reducing manure volume and nutrient runoff. However, its narrow scope and significant risks warrant careful consideration.

The Risks of Using PAM for Livestock Manure Treatment

While PAM is effective for solid-liquid separation, its use in manure treatment comes with several long-term risks that could undermine environmental sustainability and farm operations. Here are the key concerns:

1. Potential Release of Toxic Acrylamide
   PAM can degrade into acrylamide, a neurotoxin and potential carcinogen, under certain conditions like sunlight exposure. Even though commercial PAM contains low acrylamide levels (<0.05%), degradation can release up to 70 ppm in soil conditioners after 2–5 weeks (Polyacrylamide degradation and its implications in environmental systems). Acrylamide is highly mobile in water, persisting for over two months in tap water, posing risks to groundwater and regulatory compliance (Polyacrylamide in Agriculture and Environmental Land Management). For producers, this introduces uncertainty about long-term environmental safety.

2. Disruption of Soil Microbial Communities
   Cationic PAM, commonly used in manure treatment, can harm naturally occurring bacteria by disrupting cell membranes due to its positive charge (Cationic polyacrylamide as a strengthening agent). While standard rates (10–140 mg/L) have minimal impact, high or repeated applications may reduce microbial diversity, particularly in sensitive ecosystems (Polyacrylamide (PAM) in agriculture and environmental land management). This could impair soil health, critical for natural manure decomposition and nutrient cycling, unlike NGA’s microbial enhancement.

3. Limited Scope in Manure Breakdown
   PAM’s primary function is physical separation of solids and liquids, addressing only one aspect of manure management. It does not engage with the natural biological processes that break down manure into plant-usable forms. Unlike NGA, which uses aerobic bacteria and enzymes to decompose organic matter and reduce ammonia, PAM leaves the organic content largely intact, missing opportunities to enhance nutrient bioavailability or reduce odors. This narrow focus limits its contribution to sustainable agriculture.

4. Increased Sludge Management Challenges
   PAM generates significant sludge by flocculating solids, which must be stored, composted, or transported off-site. This increases operational costs and complexity, as sludge can add up to 1 g/L of solids per g/L of PAM used (Man428 PAM and Wastewater.pdf). In contrast, NGA reduces sludge buildup through microbial digestion, simplifying waste management (Additives for Improving Hog Farm Air Quality).

5. Potential Incompatibility with Microbial Solutions
   For producers considering integrated approaches, cationic PAM’s antimicrobial properties could harm beneficial bacteria in microbial products like NGA. At concentrations above 100 mg/L, PAM may disrupt bacterial cell walls, potentially reducing the efficacy of NGA’s aerobic bacteria (Antimicrobial properties of cationic polymers). This necessitates careful application strategies, adding complexity compared to NGA’s straightforward lagoon application.

6. Environmental Persistence Concerns
   Although PAM degrades at about 10% per year, its polyacrylate backbone can persist longer in soil, potentially affecting long-term soil structure (Microbial degradation of polyacrylamide and the deamination product polyacrylate). This contrasts with NGA’s natural ingredients, which mimic healthy soil processes without synthetic residues.

Why NGA Offers a Better Path Forward

Unlike PAM’s chemical approach, NGA harnesses nature’s blueprint to address manure challenges holistically. Composed of four families of aerobic soil bacteria, plant enzymes, and oxygen-releasing percarbonate, NGA activates in manure to reduce ammonia, break down organic matter, and restore pH to a plant-friendly range. This biological process not only mitigates odors and sludge but also enhances nutrient availability for crops.

NGA’s advantages over PAM products include:

• Comprehensive Manure Remediation: NGA tackles ammonia, odors, and sludge through microbial digestion, unlike PAM’s focus on separation alone.
• No Toxic Byproducts: With no synthetic components, NGA avoids risks like acrylamide release, ensuring environmental safety.
• Support for Soil Health: NGA’s bacteria enhance soil microbial activity, promoting natural nutrient cycling, while PAM may disrupt it.
• Simplified Application: NGA’s low-volume spray application is straightforward, requiring very little material handling per treatment.

Conclusion: Choose Sustainability with NGA

While PAM products offer effective solid-liquid separation and nutrient reduction, their risks—acrylamide release, microbial disruption, and limited biological engagement—make them a less sustainable choice for livestock manure management. NGA, by contrast, provides a natural, comprehensive solution that aligns with nature’s processes, reducing manure problems while enhancing soil health and environmental safety. For producers seeking to minimize risks and maximize long-term benefits, NGA is the clear choice for a cleaner, greener future in livestock operations.

Sources Summary:

• Solid-Liquid Separation of Flushed Swine Manure with PAM
• Additives for Improving Hog Farm Air Quality
• Polyacrylamide as an organic nitrogen source for soil microorganisms
• Solid-Liquid Separation of Flushed Swine Manure with PAM
• Polyacrylamide degradation and its implications in environmental systems
• Polyacrylamide in Agriculture and Environmental Land Management
• Cationic polyacrylamide as a strengthening agent
• Polyacrylamide (PAM) in agriculture and environmental land management
• Antimicrobial properties of cationic polymers
• Microbial degradation of polyacrylamide and the deamination product polyacrylate

At Under the Slats, we’re committed to revolutionizing livestock manure management with our NGA (Next Generation Animal Agriculture) product, a natural, microbial solution designed to transform manure into a valuable resource for sustainable agriculture. As producers explore options to tackle manure challenges, polyacrylamide (PAM) products often come up as a competing solution. While PAM offers some benefits for manure treatment, its risks and narrow scope make it less ideal compared to the holistic approach of NGA. Let’s dive into the pros and cons of PAM and why NGA stands out for environmentally conscious livestock operations.