National Organic Standards Board

Handling Subcommittee

Petitioned Material Proposal

Cetylpyridinium Chloride (CPC)

February 15, 2022

Summary of Petition, Petition addendum #1 

Cetylpyridinium chloride (CPC), CAS #123-03-5, is being petitioned by Safe Foods Corporation as an 

antimicrobial processing aid specifically for application onto poultry or poultry parts at slaughter or 

processing plants. As such it is being petitioned to be listed on the National List at 7 CFR 205.605(b), 

synthetic nonagricultural (nonorganic) substance allowed in or on processed products labeled as 

“organic” or “made with organic (specified ingredients).” CPC would be added to water used as a drench

or dip to reduce populations of foodborne pathogens such as Salmonella and Campylobacter that may 

be present on raw poultry. The petitioner’s proposed listing is “Cetylpyridinium chloride – Antimicrobial 

food treatment for use according to FDA limitation.” The petition was received on 12/4/2019 (referred 

to as “petition”) and amended on 4/24/2021 (referred to as “addenda”). A Technical Review (TR) was 

completed and found sufficient on 8/5/2021 (referred to as “TR”). The Handling Subcommittee is 

bringing this petition forward for full NOSB review at its Spring 2022 meeting.

Summary of Review:

The Handling Subcommittee has reviewed the relevant information on the cetylpyridinium chloride 

petition and discussed a range of specific issues.

One critical issue outlined in this proposal relates to the fact that CPC residues have been discovered on 

treated surfaces and poultry skin, exposing consumers to unlabeled pesticide residues.

Another relates to continued concern about sanitizer usage and regulation in organics and whether or 

not expansion of the sanitizer toolkit to support food safety requirements is essential for organic 

production. Previously, the NOSB has heard from an expert panel on sanitizers on the need for 

appropriate sanitizer rotations to prevent pathogen resistance and what material rotations can ensure 

appropriate efficacy. CPC is a powerful antimicrobial and raises questions about its fit with organic 

production. Significantly, another antimicrobial petition – for peroxylactic acid (POLA) – is currently 

before the NOSB on a different timeline, and its relevance to the CPC review is expected.

The fact that CPC requires the use of an inert – propylene glycol (PG) – to complete its formulation, as 

outlined in full in the TR, raises another important question. Under OFPA reviews for handling do not 

include any guidance provisions for inerts like PG. However, because the inert PG is a functional 

requirement of the CPC formulation, the Subcommittee is facing – and has discussed – what is an 

unprecedented evaluation pathway for this material in its full application.

Nonetheless, the Subcommittee has reviewed CPC on the merits for its compatibility with OFPA and 

organic systems. 

Reference Material:

Petition: https://www.ams.usda.gov/sites/default/files/media/CPC_PetitionAddendum1.pdf

Addendum: https://www.ams.usda.gov/sites/default/files/media/CPC_PetitionAddendum1.pdf

Technical Report (TR):

https://www.ams.usda.gov/sites/default/files/media/NOPCetylpyridiniumChlorideHandlingTR.pdf

NOSB Proposals and Discussion Documents April 2022 Page 23 of 152
Other – Biomonitoring California – Quaternary Ammonium Compounds (QACs):

https://biomonitoring.ca.gov/events/biomonitoring-california-scientific-guidance-panel-meeting-march2021

Category 1: Classification 

1. Substance is for: ____X___ Handling _______ Livestock

2. For HANDLING and LIVESTOCK use: 

a. Is the substance _______ Agricultural or ___X____ Non-Agricultural?

Describe reasoning for this decision using NOP 5033-2 as a guide: 

CPC is a non-agricultural synthetic substance. 

b. If the substance is Non-agricultural, is the substance _____ Non-synthetic or __X__ 

Synthetic? 

Is the substance formulated or manufactured by a process that chemically changes a 

substance extracted from naturally occurring plant, animal, or mineral sources? [OFPA 

§6502(21)] If so, describe, using NOP 5033-1 as a guide:

According to the TR, “Cetylpyridinium chloride is a synthetic substance produced by reacting pyridine 

and cetyl chloride (1-chlorohexadecane) at an elevated temperature and pressure. The majority of 

commercial pyridine is produced through the Chichibabin reaction between acrolein, formaldehyde, and 

ammonia. According to the petition, the pyridine for this synthesis is produced exclusively from 

bioethanol components (USDA 2019). Bioethanol is formed through the fermentation of biomass such 

as corn or sugarcane to form biologically sourced ethanol... Once formed, ethanol and methanol can be 

oxidized to produce acetaldehyde and formaldehyde, respectively... Acetaldehyde and formaldehyde 

can then be combined to produce acrolein, which can be further reacted with formaldehyde and 

ammonia to form pyridine via the Chichibabin reaction....” Although not likely to be present in the final 

product, precursors to manufacture CPC include formaldehyde and acetaldehyde, both probable or 

known carcinogens ((https://oehha.ca.gov/proposition-65); https://www.epa.gov/iris), and acrolein is a 

respiratory irritant (https://oehha.ca.gov/chemicals/acrolein).

The pyridine ring is reacted with cetyl chloride to form CPC (Equation 5 from the TR). The source of cetyl 

chloride (CC) (synonym: 1-Chlorohexadecane/ CAS # 4860-03-1) is not described in the petition or TR.

Manufacturing information about CC was not available from the petition, TR, PubChem, EPA, or ECHA. 

Cetyl chloride is considered an irritant with a “Warning” label but does not appear very toxic 

(https://pubchem.ncbi.nlm.nih.gov/compound/1-chlorohexadecane).

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Category 2: Adverse Impacts 

1. What is the potential for the substance to have detrimental chemical interactions with other 

materials used in organic farming systems? [§6518(m)(1)]

As petitioned for use only as a drench or dip for poultry carcasses or parts, it is unlikely that that CPC will 

interact with other materials used in organic farming systems.

2. What is the toxicity and mode of action of the substance and of its breakdown products or any 

contaminants, and their persistence and areas of concentration in the environment? 

[§6518(m)(2)]

CPC is a quaternary ammonium compound (QAC) used as a microbicide. QAC use in general has 

increased due to COVID-19 safety protocols. To date, no QACs are present on the National List. In 

contrast to many other sanitizers on the National List, CPC is not an oxidant. It “has been reported to be 

more effective against Gram-positive bacteria.” As paraphrased from the TR: Gram-positive bacteria 

have membrane surfaces that bear a negative charge. The positively charged pyridinium portion of the 

substance binds to the negatively charged bacterial membrane through electrostatic interactions. The 

electrostatic attraction improves the ability of the substance to rearrange membrane lipids. Additionally, 

the binding of the positively charged pyridinium portion of the substance disrupts membrane function 

and bacterial metabolism, which may deactivate bacteria. Once initial bacterial populations have been 

reduced, cetylpyridinium-chloride-treated meat products have been shown to maintain reduced 

bacterial populations when stored between 14 and 42 days.

At high concentrations, CPC is toxic to humans. CPC is identified as a hazardous substance according to 

the Global Harmonized System of Classification and Labeling of Chemicals (GHS) and summarized in 

Table 3 from the TR:

Class 1 reflects the highest danger and Class 4 reflects the lowest danger. CPC represents higher risks 

(Class 1-2) for skin corrosion/irritation, ocular damage, and inhalation toxicity. Like many toxicants, the 

dose makes the poison, and lower health-based benchmarks have been established for CPC where 

adverse effects in humans, when exposed, would be unlikely to occur. QACs exposure in general was 

reviewed by the California Biomonitoring Science Guidance Panel, which raised some concerns about 

long-term exposure and recommended biomonitoring of QACs to better understand exposure trends. Of 

note, no occupational air monitoring data was reported in the petition, TR, or by EPA, NIOSH, ECHA, or 

aggregated data bases such as EWG. Similar to other sanitizers, it appears that there is little data to 

assess inhalation exposures in occupational environments where this sanitizer is approved for use. 

While exposures may be low because relatively dilute solutions are used as a microbicide, and because 

NOSB Proposals and Discussion Documents April 2022 Page 25 of 152
QACs, in particular, are not highly volatile, information on potential exposures would be valuable. 

Toxicology data submitted by the petitioner does not address inhalation exposures.

CPC is approved for use in many consumer products, including mouthwash, toothpaste, and other 

products contacting oral cavities in humans. These uses almost certainly result in ingestion and dermal 

exposures that are deemed safe by FDA. As excerpted in the petition “...the FDA concluded that the noobservable effect level (NOEL) for the dog [study] ... was 8 mg/kg body weight per day. By applying a 

1000-fold safety factor to this value, the FDA determined the acceptable daily intake (ADI) for a 60-kg 

human as 0.48 mg/p/d.” This is quoted as an excerpt from FDA Code of Federal Register (CFR 173.375).

The FDA ADI converts to 0.008 mg/kg-bw, which are more common units used by EPA.

According to the TR: “FDA has approved the use of cetylpyridinium chloride “as an antimicrobial

agent...to treat the surface of raw poultry carcasses” (21 CFR 173.375). The FDA requires

cetylpyridinium chloride to be combined with propylene glycol (PG), which must be included “at a 

concentration of 1.5 times that of cetylpyridinium chloride.” When used as an antimicrobial additive in 

poultry processing, the FDA has outlined its use in §173.375.” Note, propylene glycol is on EPA List 4 and 

is on the National List at 205.603(a): only for treatment of ketosis in ruminants.

As described in the TR, CPC is petitioned for use as a drench or dip followed by a chiller solution or a 

potable water wash when used in post-chiller applications, as stipulated by FDA regulations (21 CFR 

173.375). The continued processing is expected to remove the majority of CPC from treated surfaces.

However, residual CPC has been detected on treated surfaces at the processing endpoint and is 

expected to be found in concentrations of 2.–25.9 mg/kg on poultry skin. The maximum reported 

concentration of 25.9 mg/kg found on the meat surface would result in an average concentration of 2.3

mg/kg of CPC on treated meat. In the information reviewed, CPC was not found in non-surface meat. 

The TR concludes that CPC exposure is not expected to pose safety concerns (EFSA 2012). Importantly, 

organic consumers would be exposed to unlabeled pesticide residues (and propylene glycol) in the food.

For the proposed use PG will be regulated as an “inert” substance from the EPA List 4. Note, the List 4 is 

not supported by EPA and is a legacy guideline for organic pesticides.

As described in the TR (Table 2), CPC is “highly toxic to fish, crustaceans, molluscs, and other aquatic 

life.” 

According to the petition, “At the end of a processing day, the entire CPC application system is shut 

down and any solution remaining in the recycle tank is sent to a purge tank. The frequency of this 

purging varies from one plant to another, although a daily purging is typical. The purged solution is 

filtered to remove any remaining CPC using disposable carbon filters. The activated carbon treatment 

provides for complete removal of CPC from the aqueous treatment solution.” The TR describes similar 

procedures.

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3. Describe the probability of environmental contamination during manufacture, use, misuse or 

disposal of such substance? [§6518(m)(3)]

According to the petition, “the CPC is captured in carbon barrels and disposed of either in approved 

landfills or by incineration. Disposal of the carbon barrels by either method does not allow for free CPC 

to enter the environment. Typically, a plant will use and dispose of one carbon filter (55-gallon drum or 

209-L drum) every two months. The filtered, CPC-free liquid is then combined with the plant 

wastewater. In addition, available data for commercial CPC applications indicate that CPC, if present at 

all in the effluent from wastewater treatment facilities following the capture and recycling processes, 

will be there in vanishingly low levels and will be of no environmental significance” and “under the 

Notice and Comment rulemaking for CPC use, the FDA issued a Finding of No Significant Impact (FONSI) 

for CPC application to raw poultry.”

Based on the information provided, environmental contamination resulting from use as a processing aid 

in poultry manufacturing lines is unlikely as long as the controls described in the petition and TR are 

followed. As noted above and described in the TR, precursor materials are likely to include 

formaldehyde and acetaldehyde, both probable or known carcinogens 

((https://oehha.ca.gov/proposition-65); https://www.epa.gov/iris) and acrolein is a respiratory irritant 

(https://oehha.ca.gov/chemicals/acrolein). CPC manufacture and use is regulated, but inappropriate 

handling or accidents could result in human exposures or environmental emissions along the supply 

chain. It is impossible to quantify the probability of such events. 

4. Discuss the effect of the substance on human health. [§6517 (c)(1)(A)(i); §6517 (c)(2)(A)(i); 

§6518(m)(4)]. 

See above.

5. Discuss any effects the substance may have on biological and chemical interactions in the 

agroecosystem, including the physiological effects of the substance on soil organisms (including 

the salt index and solubility of the soil), crops and livestock. [§6518(m)(5)]

Not applicable.

6. Are there any adverse impacts on biodiversity? (§205.200)

Not applicable.

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Category 3: Alternatives/Compatibility 

1. Are there alternatives to using the substance? Evaluate alternative practices as well as nonsynthetic and synthetic available materials. [§6518(m)(6)]

Non-synthetic alternatives include plain water and organic acids (e.g., including citric acid, lactic acid, 

and tartaric acid). These materials may affect food quality or are not efficacious for an industrial poultry 

production line, or, in the case of lactic acid, is more commonly used in livestock. 

Several existing materials on the National List are currently used as poultry processing aids and comply 

with food safety requirements. Peroxyacetic acid, in particular, is widely used. According to the TR, 

peroxyacetic acid is an oxidant microbicide applied as both a pre- and post-chill treatment as a spray or 

dip. Chlorine materials include chlorine dioxide and hypochlorous acid and acidified sodium chlorite 

(ASC), a related material. ASC is approved for poultry processing. As noted in the TR, the oxidizing 

nature of chlorine materials makes them susceptible to deactivation when interacting with organic 

matter.

2. For Livestock substances, and Nonsynthetic substances used in Handling: In balancing the 

responses to the criteria above, is the substance compatible with a system of sustainable 

agriculture? [§6518(m)(7)]

No. This synthetic material offers some benefits for pathogen control on poultry carcasses and parts. 

However, existing materials have supported a robust and growing organic poultry industry and currently 

allow compliance with food safety standards. Importantly, use of this material will result in unlabeled 

pesticide residues on organic food and exposures to organic consumers without their knowledge, factors 

antithetical to organic principles.

Category 4: Additional criteria for synthetic substances used in Handling (does not apply to 

nonsynthetic or agricultural substances used in organic handling):

Describe how the petitioned substance meets or fails to meet each numbered criterion.

1. The substance cannot be produced from a natural source and there are no organic substitutes; 

(§205.600(b)(1)) 

CPC is synthetic and cannot be produced from natural sources.

2. The substance's manufacture, use, and disposal do not have adverse effects on the environment 

and are done in a manner compatible with organic handling; (§205.600(b)(2)) 

If good manufacturing and handling practices are followed, it is unlikely that the environmental 

contamination will result from the petitioned use. Use of the material does result in periodic waste 

material that must be disposed of in a landfill. As noted above and described in the TR, precursor 

materials are likely to include formaldehyde and acetaldehyde, both probable or known carcinogens 

((https://oehha.ca.gov/proposition-65); https://www.epa.gov/iris) and acrolein is a respiratory irritant 

(https://oehha.ca.gov/chemicals/acrolein). CPC manufacture and handling is regulated, but 

inappropriate handling or accidents could result in human exposures or environmental emissions along 

the supply chain. It is impossible to quantify the probability of such events.

NOSB Proposals and Discussion Documents April 2022 Page 28 of 152
3. The nutritional quality of the food is maintained when the substance is used, and the substance, 

itself, or its breakdown products do not have an adverse effect on human health as defined by 

applicable Federal regulations; (§205.600(b)(3)) 

The nutritional quality of the food is not affected by use of CPC. Use of this material will result in 

unlabeled pesticide residues (and propylene glycol) on organic food and exposures to organic consumers 

without their knowledge, factors antithetical to organic principles.

4. The substance's primary use is not as a preservative or to recreate or improve flavors, colors, 

textures, or nutritive value lost during processing, except where the replacement of nutrients is 

required by law; (§205.600(b)(4)) 

CPC is not used as a preservative or to recreate or improve flavors, colors, textures.

The substance is listed as generally recognized as safe (GRAS) by the Food and Drug Administration 

(FDA) when used in accordance with FDA's good manufacturing practices (GMP) and contains no 

residues of heavy metals or other contaminants in excess of tolerances set by FDA; (§205.600(b)(5)) 

CPC is unlikely to contain heavy metals. Propylene glycol (PG) must be used in the formulation, as 

required by the FDA. PG has historically been on the now obsolete EPA List 4; however, the National List 

does not contain a provision for inerts in Handling (§205.606(b)). 

5. The substance is essential for the handling of organically produced agricultural products. 

(§205.600(b)(6)) 

The substance is not essential for organic poultry production. A robust and growing organic poultry 

industry is supported by existing materials.

6. In balancing the responses to the criteria in Categories 2, 3 and 4, is the substance compatible 

with a system of sustainable agriculture [§6518(m)(7)] and compatible with organic handling?

(see NOSB Recommendation, Compatibility with Organic Production and Handling, April 2004) 

The NOSB finds merits for this material, particularly around the need for alternative sanitizers in organic 

processing. However, existing materials have supported a robust and growing organic poultry industry 

and currently allow compliance with food safety standards. Importantly, use of this material will result in 

unlabeled pesticide residues on organic food and exposures to organic consumers without their 

knowledge, factors antithetical to organic principles. At this time, the Subcommittee is not 

recommending this material for inclusion on the National List.

Questions for Stakeholders

1. Do stakeholders agree that this review of CPC – without a deeper review of the inert propylene 

glycol – is appropriate?

2. Since the FDA requires that propylene glycol be in a CPC formulation, how should the committee 

evaluate future petitions that include inerts in the formulation given that there is no provision 

for such inerts within the handling section of the National List?

3. In the current food safety regulatory environment, do organic producers have effective tools for 

pathogens in poultry processing (specifically antimicrobials)? 

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Classification Motion

Motion to classify cetylpyridinium chloride (CPC) as a non-agricultural synthetic substance

Motion by: Wood Turner

Seconded by: Kyla Smith

Yes: 6 No: 0 Abstain: 0 Absent: 0 Recuse: 0

National List Motion

Motion to add cetylpyridinium chloride (CPC) with the following annotation: “CPC can only be used in 

formulation with propylene glycol per FDA requirements” at 7 CFR 205.605(b) 

Motion by: Wood Turner

Seconded by: Kyla Smith

Yes: 0 No: 6 Abstain: 0 Absent: 0 Recuse: 0

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