FDA Approval for Water Treatment Chemicals — Food Contact and Drinking Water Standards

Water treatment chemicals used in food and beverage production, pharmaceutical manufacturing, and drinking water applications must meet stringent regulatory requirements to ensure they do not introduce harmful contaminants into the water supply. In the United States, the U.S. Food and Drug Administration (FDA) oversees the regulation of water treatment chemicals that may come into contact with food or are used in drinking water treatment. Understanding FDA regulations, 21 CFR requirements, and GRAS status is essential for food processors, water utilities, and chemical suppliers alike. This article provides a comprehensive overview of polyaluminum chloride (PAC), polyacrylamide (PAM), activated carbon, and other key water treatment chemicals under FDA regulations.

The FDA Regulatory Framework for Water Treatment Chemicals

The FDA regulates water treatment chemicals through several different pathways depending on their intended use. The primary regulatory mechanisms include:

• Food Contact Substances (FCS) — Chemicals used in water that comes into contact with food during processing, washing, or transport are regulated as indirect food additives under 21 CFR Part 173
• Drinking Water Additives — Chemicals added to drinking water are regulated under the Safe Drinking Water Act (SDWA), with the EPA setting primary standards and the FDA providing food safety oversight
• Generally Recognized as Safe (GRAS) — Substances that experts generally consider safe for their intended use may be exempt from formal FDA pre-market approval
• Food Contact Notifications (FCN) — Manufacturers can notify FDA of new food contact substances through the FCN program

It is important to note that the FDA does not “approve” water treatment chemicals in the same way it approves drugs or medical devices. Instead, it establishes regulations that specify which substances may be used, under what conditions, and at what levels. Chemicals that meet these regulatory requirements are considered compliant for their intended use. The FDA Food Additive Status List provides a searchable database of substances regulated as food additives, including those used in water treatment for food processing applications. Working with suppliers that provide products meeting FDA-compliant specifications and proper documentation is essential for food and beverage manufacturers.

21 CFR Part 173: Secondary Direct Food Additives

Title 21 of the Code of Federal Regulations, Part 173, governs “Secondary Direct Food Additives Permitted in Food for Human Consumption.” This regulation includes specific provisions for various water treatment chemicals used in food processing. Subpart D (Sections 173.300-173.390) covers coagulants, flocculants, filter aids, and other water treatment chemicals that may come into contact with food.

Key sections relevant to water treatment include:

21 CFR Section	Substance Category	Examples
173.300	Aluminum sulfate	Alum (coagulant)
173.305	Calcium hydroxide	Lime (pH adjustment)
173.310	Sodium hypochlorite	Bleach (disinfection)
173.315	Potassium permanganate	Oxidant, taste/odor control
173.320	Activated carbon	Adsorbent, taste/odor control
173.340	Polyacrylamide resins	PAM (flocculant)
173.345	Polyelectrolytes (cationic)	Cationic polymers
173.348	Poly(diallyldimethylammonium chloride)	PolyDADMAC (coagulant aid)

Each section specifies the conditions under which the substance may be used, including limitations on use level, purity requirements, and the types of food processing operations where it is permitted. Facilities using these chemicals must ensure they use them in accordance with the specified conditions to maintain regulatory compliance.

GRAS Status: What It Means for Water Treatment Chemicals

Generally Recognized as Safe (GRAS) is a designation for substances that are generally recognized, among experts qualified by scientific training and experience, as safe for their intended use under the conditions of their intended use. GRAS substances are exempt from the formal pre-market approval requirements that apply to food additives.

There are two types of GRAS determinations:

• FDA-affirmed GRAS — Substances that the FDA has specifically affirmed as GRAS through regulation, found in 21 CFR Parts 182 and 184
• Self-determined GRAS — Substances for which a manufacturer or other party has independently concluded the substance is GRAS, based on generally available scientific data

Some water treatment chemicals, like certain forms of activated carbon and some coagulant aids, may have GRAS status. However, it is important to understand that GRAS status is specific to the intended use and conditions of use. A substance that is GRAS for one application may not be GRAS for another, and the burden of ensuring GRAS status rests with the party using the substance. Food processors should always verify the regulatory status of water treatment chemicals with their supplier and maintain appropriate documentation.

Polyaluminum Chloride (PAC) and FDA Compliance

Polyaluminum chloride is one of the most widely used coagulants in water treatment, including applications in food and beverage processing and drinking water treatment. While aluminum sulfate (alum) has a long history of FDA regulation under 21 CFR 173.300, PAC is a more advanced coagulant that offers several performance advantages including higher charge density, wider effective pH range, and lower sludge production.

Regulatory Pathways for PAC

PAC used in food processing water treatment falls under the category of coagulants that may be used in water that comes into contact with food. The specific regulatory requirements depend on the application:

• Drinking water treatment — PAC must meet ANSI/NSF Standard 60 requirements for drinking water treatment chemicals, which sets health effects-based limits for contaminants in the product itself
• Food processing water — PAC used in water that contacts food must meet appropriate food-grade purity specifications and be used at the minimum level necessary to achieve the intended technical effect
• Wastewater treatment — PAC used solely for wastewater treatment (where the treated water is discharged and does not contact food) is not subject to FDA food contact regulations, though it may be subject to EPA discharge limits

Purity and Heavy Metal Limits

For food-contact and drinking water applications, PAC must meet strict purity requirements, particularly for heavy metals. Key parameters include:

Parameter	Typical Food-Grade Limit	Regulatory Reference
Arsenic	≤ 10 mg/kg	NSF 60 / drinking water standards
Cadmium	≤ 5 mg/kg	Various food additive regulations
Lead	≤ 10 mg/kg	Various food additive regulations
Mercury	≤ 1 mg/kg	Various food additive regulations
Chromium (VI)	≤ 10 mg/kg	Drinking water standards
Iron	Specification-dependent	Product standard
Insoluble matter	≤ 0.5%	Product standard

When selecting a PAC supplier for food or drinking water applications, it is critical to verify that the product meets the appropriate purity standards and that the supplier can provide certificates of analysis (COAs) documenting compliance. Reputable suppliers maintain ISO 9001 quality management systems and regularly test their products to ensure consistent quality.

Polyacrylamide (PAM) and FDA Regulations

Polyacrylamide flocculants are specifically addressed under 21 CFR 173.340, which covers “Polyacrylamide resins and modified polyacrylamide resins used as flocculants, coagulants, and settling and filtration aids in the processing of food.” This regulation specifies the conditions under which PAM may be used in food processing applications.

21 CFR 173.340 Requirements

Under 21 CFR 173.340, polyacrylamide resins used in food processing must meet the following conditions:

• The resin must be the product of polymerization of acrylamide with one or more optional comonomers
• Residual acrylamide monomer content must not exceed 0.05% (500 ppm) by weight of the resin as used (this is a critical safety requirement, as acrylamide is a neurotoxin and probable carcinogen)
• The resin must be used at the minimum level necessary to achieve the intended technical effect
• The resin must be used in accordance with good manufacturing practice (GMP)

It is important to note that the 0.05% limit applies to the polymer as used, not just as manufactured. For emulsion polymers, this means the active polymer content must be considered when calculating residual acrylamide levels. Facilities using PAM in food processing should obtain documentation from their supplier confirming that the product meets 21 CFR 173.340 requirements, including residual acrylamide content specifications.

Anionic, Cationic, and Nonionic PAM — Regulatory Differences

The regulation of PAM products varies by charge type. Anionic and nonionic PAM have a long history of use in food processing and are generally well-covered by existing regulations. cationic PAM, which often contains cationic monomers like DADMAC or acryloyloxyethyltrimethyl ammonium chloride (AETAC), may fall under different regulatory sections depending on the specific monomer composition. Understanding the differences between anionic, cationic, and nonionic PAM is important not just for performance but also for regulatory compliance.

For food processing applications, anionic PAM is most commonly used in primary clarification following metal salt coagulation. Cationic PAM is more typically used for sludge dewatering, where the polymer is incorporated into the sludge cake and does not typically come into contact with food contact water streams. Facilities should always verify that the specific grade of PAM they are using is appropriate for its intended use under FDA regulations.

Activated Carbon for Food and Drinking Water Applications

Activated carbon is widely used in food and beverage processing for removing taste, odor, color, and organic contaminants from process water. It is regulated under 21 CFR 173.320, which specifies that activated carbon used in the processing of food must be manufactured from approved raw materials and used in accordance with good manufacturing practice.

For drinking water applications, activated carbon (both granular and powdered) is also subject to ANSI/NSF Standard 61 requirements for drinking water system components. Key quality parameters for food-grade activated carbon include:

• Iodine number and methylene blue value (activity indicators) — see our guide to iodine and methylene blue values
• Ash content and water-soluble ash
• Heavy metal content (arsenic, lead, cadmium, mercury)
• Particle size distribution
• Moisture content

NSF/ANSI Standards for Drinking Water Chemicals

While FDA regulations focus on food safety, the National Sanitation Foundation (NSF) develops standards for drinking water treatment chemicals and materials that are widely recognized and often required by state and local regulators. NSF/ANSI Standard 60 (“Drinking Water Treatment Chemicals — Health Effects”) establishes minimum health effects requirements for chemicals that are added to drinking water as part of the treatment process.

NSF 60 certification is often required for:

• Coagulants (PAC, alum, ferric chloride)
• Flocculants (PAM and other polymers)
• Disinfectants (chlorine, ozone, UV systems)
• pH adjusters (lime, caustic soda, sulfuric acid)
• Adsorbents (activated carbon)
• Scale and corrosion inhibitors

While NSF certification is not an FDA requirement per se, it is often referenced by regulatory agencies and is considered a benchmark for drinking water chemical safety. Facilities purchasing water treatment chemicals for potable water applications should verify NSF 60 certification or equivalent compliance documentation from their suppliers.

Compliance Best Practices for Food and Beverage Manufacturers

Supplier Qualification

The foundation of FDA compliance for water treatment chemicals is working with qualified, reputable suppliers. When evaluating potential suppliers, food manufacturers should:

• Verify that products meet the appropriate FDA regulations and purity specifications
• Request certificates of analysis (COAs) for each shipment, confirming key quality parameters
• Confirm that the supplier operates under appropriate quality management systems (e.g., ISO 9001)
• Review the supplier’s regulatory documentation and compliance history
• Consider how to verify a water treatment chemical supplier before making purchasing decisions

Documentation and Record-Keeping

FDA inspections require comprehensive documentation. Facilities using water treatment chemicals in food processing should maintain records including:

• Supplier qualification documentation
• Certificates of analysis for each shipment
• Material safety data sheets (MSDS/SDS)
• Usage records showing chemical consumption and dosing rates
• Process water quality monitoring data
• Standard operating procedures (SOPs) for chemical handling and dosing

Use at Minimum Necessary Levels

A key principle of FDA regulation of food processing chemicals is that they should be used at the minimum level necessary to achieve the intended technical effect. This means facilities should optimize their dosing rates to avoid overuse of chemicals. Regular jar testing and process monitoring can help ensure that chemicals are dosed efficiently, both for cost control and regulatory compliance. Understanding the difference between coagulation and flocculation and how to optimize each process is essential for minimizing chemical usage.

International Regulatory Considerations

While this article focuses on FDA regulations, it is important to note that other countries have their own regulatory frameworks for water treatment chemicals. In the European Union, for example, water treatment chemicals used in drinking water must comply with the Drinking Water Directive and relevant EN standards. In China, GB standards apply to both drinking water and food processing chemicals.

For companies sourcing chemicals internationally, it is important to work with suppliers that understand multiple regulatory regimes and can provide products that meet the specific standards of the target market. REACH compliance, for example, is essential for chemicals sold in the European Union. When importing from countries like China, understanding the sourcing landscape and verifying supplier quality systems becomes even more important.

Conclusion

FDA regulation of water treatment chemicals is a complex but essential framework that protects public health by ensuring the safety of chemicals used in food processing and drinking water treatment. Key regulations like 21 CFR Part 173 set specific conditions for the use of coagulants, flocculants, and other water treatment chemicals in food contact applications. For PAC, PAM, and activated carbon — the workhorses of modern water treatment — meeting FDA and NSF standards requires careful product selection, rigorous quality control, and proper documentation.

Food and beverage manufacturers, water utilities, and other facilities subject to FDA oversight can ensure compliance by working with qualified, reputable suppliers that provide well-documented, high-quality products. At HydroChemix, we supply a range of water treatment chemicals suitable for various applications, including products that meet food-grade and drinking water purity specifications. Our technical team can help you select the right products for your specific application and provide the documentation needed to support your compliance efforts. Contact us today to learn more.

Frequently Asked Questions

Does the FDA “approve” water treatment chemicals?

No, the FDA does not approve individual water treatment chemical products in the way it approves drugs. Instead, the FDA establishes regulations (such as those in 21 CFR Part 173) that specify which substances may be used in food processing, under what conditions, and at what levels. Chemicals that meet these regulatory specifications are considered compliant. Some substances may also have GRAS (Generally Recognized as Safe) status. It is the user’s responsibility to ensure that chemicals are used in accordance with applicable regulations.

What is the maximum allowable residual acrylamide in PAM for food processing?

Under 21 CFR 173.340, polyacrylamide resins used as flocculants in food processing must contain no more than 0.05% (500 ppm) residual acrylamide monomer by weight of the resin as used. This limit is critical because acrylamide is a neurotoxin and probable human carcinogen. Facilities using PAM in food processing should obtain certificates of analysis from their suppliers confirming that residual acrylamide levels meet this requirement. High-quality PAM products from reputable manufacturers typically have residual acrylamide levels well below this limit.

Is PAC approved for use in drinking water treatment?

Polyaluminum chloride is widely used in drinking water treatment and is accepted under drinking water regulations worldwide, including in the United States. While it is not specifically listed as a separate entry in 21 CFR Part 173 (unlike aluminum sulfate, which is listed at 173.300), PAC used in drinking water must meet ANSI/NSF Standard 60 requirements for drinking water treatment chemicals, which establish health-effects-based limits for contaminants. For food processing water treatment, PAC must meet appropriate food-grade purity specifications and be used at the minimum level necessary to achieve the intended effect.

What is the difference between FDA food contact approval and NSF 60 certification?

FDA food contact regulations (21 CFR Part 173) govern chemicals used in water that comes into contact with food during processing, focusing on ensuring that the chemicals do not adulterate food or pose a food safety risk. NSF/ANSI Standard 60 is a standard for drinking water treatment chemicals that establishes health effects requirements for chemicals added to potable water. While both address chemical safety, FDA regulations have a food safety focus and are enforced by the FDA, while NSF 60 has a drinking water health focus and is often required by state drinking water regulators. For chemicals used in both drinking water and food processing, both standards may apply.

What documentation should I obtain from my chemical supplier for FDA compliance?

For FDA compliance in food processing applications, you should obtain the following documentation from your chemical supplier: certificates of analysis (COAs) for each shipment confirming key purity parameters including heavy metal limits and (for PAM) residual acrylamide content; material safety data sheets (MSDS/SDS); product specifications sheets; documentation of the supplier’s quality management system (e.g., ISO 9001 certification); and any regulatory compliance letters or certifications. Some suppliers may also provide technical data sheets with guidance on proper use and dosing. Verifying your supplier’s credentials is an important part of maintaining compliance.

Do wastewater treatment chemicals need FDA approval?

Water treatment chemicals used solely for wastewater treatment — where the treated water is discharged to the environment and does not come into contact with food or drinking water — are not subject to FDA food contact regulations. However, they may be subject to EPA discharge regulations and local environmental permits. The situation is different if the treated wastewater is reused for food processing or drinking water purposes, in which case the chemicals used must meet the appropriate food or drinking water standards. For wastewater-only applications, the primary considerations are treatment effectiveness, cost, and compliance with discharge limits, rather than FDA food safety requirements.