This is a proposal by a Subcommittee of the National Organic Standards Board (NOSB). Proposals are posted for public comment and 

then may be voted upon by the full Board. They are not final Board recommendations or NOP policy

Revised June 20 2013

National Organic Standards Board

Livestock Subcommittee

Petitioned Material Proposal

Chlorine Materials in Aquatic Plant Production

+

February 18, 2014

Summary of Proposed Action:

Chlorine Materials are petitioned for use in aquatic plant production, to be added to 205.609 -

Synthetic substances allowed for use in organic aquatic plant production as follows:

§ 205.609 Synthetic substances allowed for use in organic aquatic plant production. 

(a) As disinfectants and sanitizers. 

(x) Chlorine materials— Except, That, residual chlorine levels in water shall not 

exceed the maximum residual disinfectant limit under the Safe Drinking Water 

Act

(i) Calcium hypochlorite 

(ii) Chlorine dioxide 

(iii) Sodium hypochlorite

Chlorine materials are widely used for their disinfectant properties, and are currently approved 

for such uses in crop, livestock and processed organic product production. The annotations on 

the National List for livestock and handling limit the use of chlorine materials to disinfection and 

sanitation, and require that residual chlorine levels be consistent with Safe Drinking Water Act 

levels. The current listing for use in crops at 205.601(a) states:

(2) Chlorine materials—For pre-harvest use, residual chlorine levels in the water in direct 

crop contact or as water from cleaning irrigation systems applied to soil must not exceed 

the maximum residual disinfectant limit under the Safe Drinking Water Act, except that 

chlorine products may be used in edible sprout production according to EPA label 

directions.

(i) Calcium hypochlorite.

(ii) Chlorine dioxide.

(iii) Sodium hypochlorite.

The NOP has also clarified the use of chlorine in production and handling in a guidance 

document, NOP 5026.

The Livestock and Crops Subcommittees have received a petition for the use of Chlorine 

Materials in aquatic livestock and plant production. This checklist and proposal relate to the 

proposed use in aquatic plant production; a separate checklist evaluates the petitioned use in 

aquatic animal production. These materials are used in aquatic plant production for the 

disinfecting hard surfaces and culture water in nurseries, growout operations with tanks, harvest 

equipment, and in processing facilities. Because the petitioned uses of chlorine are identical for 

aquatic plants and animals, this checklist follows the same logic as the Livestock Subcomittee’s 

proposal for chlorine in aquatic animal production. Given that the materials’ use in aquaculture 

applications is identical to existing uses in other production categories, the Livestock committee 

did not requested a new Technical Evaluation Report for the petitioned use in aquatic animal 

production, but instead relied upon recent TR’s developed for Handling and Crops uses of this 

group of materials. The crops committee did request a TR for chlorine as part of the 2012 

sunset review of the material, and that 2011 TR has be utilized in the preparation of this 

checklist. 
This is a proposal by a Subcommittee of the National Organic Standards Board (NOSB). Proposals are posted for public comment and 

then may be voted upon by the full Board. They are not final Board recommendations or NOP policy

Revised June 20 2013

During the subcommittee discussion and vote, several members raised concerns as to whether 

the petition and technical review adequately address the question of whether this material is 

essential in aquatic plant production, or whether functional and commercially viable alternative 

disinfectants and sanitizers exist. The subcommittee specifically requests public comment from 

any knowledgeable stakeholders in this particular area. 

It should also be noted that at the time of drafting this proposal there are no federal standards 

promulgated for aquatic plant or animal production and this proposal is based on the NOSB 

Recommendations of standards voted in 2007, 2008 and 2009.

Evaluation Criteria 

(Applicability noted for each category; Documentation attached) Criteria Satisfied? 

1. Impact on Humans and Environment X Yes ☐ No ☐ N/A 

2. Essential & Availability Criteria X Yes ☐ No ☐ N/A

3. Compatibility & Consistency X Yes ☐ No ☐ N/A 

as Organic (only for § 205.606)

Proposed Annotation (if any): see listing motion below

Basis for annotation: X To meet criteria above ☐ Other regulatory criteria ☐ Citation 

Notes: This annotation is consistent with other listings of Chlorine on the NL, and ensures 

that any environmental impact is effectively mitigated. 

Recommended Subcommittee Action & Vote, including classification recommendation (state 

actual motion):

Classification Motion: Chlorine Materials (Calcium hypochlorite, chlorine dioxide, sodium 

hypochlorite) are synthetic.

Motion by: Joe Dickson

Seconded by: Colehour Bondera

Yes: 7 No: 0 Absent: 0 Abstain: 0 Recuse: 0

Listing Motion: Motion to list chlorine materials (Calcium hypochlorite, chlorine dioxide, 

sodium hypochlorite) at §205.609 with the following annotation: Chlorine materials -

Disinfecting and sanitizing facilities and equipment. Residual chlorine levels in the water 

shall not exceed the maximum residual disinfectant limit under the Safe Drinking Water Act.

Motion by: Joe Dickson

Seconded by: Jean Richardson

Yes: 6 No: 1 Abstain: 0 Absent: 0 Recuse: 0 

Minority Opinion: see end of document

Approved by Tracy Favre, Subcommittee Chair, to Transmit to NOSB February 23, 2014
This is a proposal by a Subcommittee of the National Organic Standards Board (NOSB). Proposals are posted for public comment and 

then may be voted upon by the full Board. They are not final Board recommendations or NOP policy

Revised June 20 2013

NOSB Evaluation Criteria for Substances Added To the National List: Crops

Category 1. Adverse impacts on humans or the environment? Chlorine Materials

Question Yes No N/A Comments/Documentation (TAP; 

petition; regulatory agency; other)

1. Is there a probability of environmental 

contamination during use or misuse? 

[§6518(m)(3)]

X 2006 Crops TR lines 212-266. The TR 

identities several areas of potential 

environmental impact, but notes that 

existing EPA regulations and the 

annotation restricting effluent to the levels 

of the Safe Drinking Water Act are 

sufficient to mitigate any environmental 

impact. The petitioner and a number of 

producers have confirmed that chlorine 

materials are not used in direct contact 

with the environment (e.g. ponds and net 

pens) and the restrictive annotation would 

prohibit such uses regardless. 

The 2011 Crops TR (lines 225-306) is 

consistent with the 2006 TR. 

2. Is there a probability of environmental 

contamination during, manufacture or 

disposal? [§6518(m)(3)]

X See Question 1

3. Does the substance contain inerts 

classified by EPA as ‘inerts of 

toxicological concern’? [§6517 

(c)(1)(B)(ii)]

X No. [2006 Crops TR; 2011 Crops TR ]

4. Is there potential for detrimental chemical 

interaction with other materials used in 

organic farming systems?

[§6518(m)(1)]

X The annotation restricts use to levels no 

greater than those determined by the 

Safe Drinking Water Act, so the potential 

for detrimental chemical interaction is 

similar to that posed by municipal tap 

water. 

5. Is there a toxic or other adverse action of 

the material or its breakdown products?

[§6518(m)(2)]

X The annotation restricts use to levels no 

greater than those determined by the 

Safe Drinking Water Act, so the potential 

for detrimental chemical interaction is 

similar to that posed by municipal tap 

water. Any presence of the substance in 

the overall agroecosytem would be 

required by the annotation to meet the 

requirements of the Safe Drinking Water 

Act, ensuring presence below 4 ppm.
This is a proposal by a Subcommittee of the National Organic Standards Board (NOSB). Proposals are posted for public comment and 

then may be voted upon by the full Board. They are not final Board recommendations or NOP policy

Revised June 20 2013

6. Is there persistence or concentration of 

the material or breakdown products in 

the environment? [§6518(m)(2)]

X No. The substance degrades rapidly to 

naturally occurring compounds in the 

presence of air and sunlight [2006 Crops 

TR 417-432] This TR also confirms (in 

lines 384 –402) that these materials are 

not persistent in the environment in 

general, and that in water and soil, 

sodium and calcium hypochlorite 

separate into sodium, calcium and 

hypochlorite ions. Chlorine dioxide is also 

reactive and breaks down quickly. While 

the TER does not directly address its fate 

in aquatic environments, again, the 

annotation would limit the extent to which 

any chlorine material could be discharged 

into sea water or any other part of the 

environment.

The 2011 Crops TR (lines 381-390) is 

consistent with the 2006 TR. 

7. Would the use of the substance be 

harmful to human health or the

environment? [§6517 (c)(1)(A)(i); §6517 

(c)(2)(A)(i); §6518(m)(4)]

X See Q # 1

8. Are there adverse biological and 

chemical interactions in the agroecosystem, including biodiversity? 

[§6518(m)(5)]

X Any presence of the substance in the 

overall agroecosytem would be required 

by the annotation to meet the 

requirements of the Safe Drinking Water 

Act, ensuring presence below 4 ppm. 

9. Are there detrimental physiological 

effects on soil organisms, crops, or

livestock? [§6518(m)(5)]

X The substance is not used in direct 

contact with soil or terrestrial livestock. It 

is only used in contact with hard surfaces 

and equipment, or culture water. [2006 

Crops TR 322-327, petition]

Category 2. Is the Substance Essential for Organic Production? Chlorine Materials

Question Yes No N/A Comments/Documentation (TAP; 

petition; regulatory agency; other)

1. Is the substance agricultural? [§6502(1)] X

2. Is the substance formulated or 

manufactured by a chemical process? 

[§6502(21)]

X Yes. 2006 TR Lines 149-171. 2011 TR 

Lines 183-211.

3. Is the substance formulated or 

manufactured by a process that 

chemically changes a substance 

extracted from naturally occurring plant, 

animal, or mineral sources? 

[§6502(21)]

X This process does not involve the 

chemical transformation of a natural 

substance; the starting materials are 

synthetic. 2006 TR Lines 177-178. 2011 

TR Lines 216-217.
This is a proposal by a Subcommittee of the National Organic Standards Board (NOSB). Proposals are posted for public comment and 

then may be voted upon by the full Board. They are not final Board recommendations or NOP policy

Revised June 20 2013

4. Is the substance created by naturally 

occurring biological processes? 

[§6502(21)]

X 2006 TR Lines 183-184. 2011 TR Lines 

222-223.

5. Is there a natural source of the 

substance? [§ 205.600(b)(1)]

X 2006 TR Lines 183-184. 2011 TR Lines 

222-223.

6. Is there an organic substitute? 

[§205.600(b)(1)]

X 2006 TR Lines 183-184. 2011 TR Lines 

222-223.

7. Is there a wholly natural substitute 

product?

[§6517(c)(1)(A)(ii)]

X While the 2011 TR does list a number of 

potential alternatives (lines 519-530), the 

petition (pages 7-8) describes compelling 

limitations of the alternatives. 

8. Are there any alternative substances? 

[§6518(m)(6)]

X See #7

9. Are there other practices that would 

make the substance unnecessary? 

[§6518(m)(6)]

X 2011 TR Lines 611-628. None of the 

alternatives are effective for cleaning 

irrigations systems. 

Category 3. Is the substance compatible with organic production practices? Chlorine Materials

Question Yes No N/A Comments/Documentation (TAP; 

petition; regulatory agency; other)

1. Is the substance consistent with organic 

farming and handling? 

[§6517(c)(1)(A)(iii); 6517(c)(2)(A)(ii)]

X The evaluation criteria above shows that 

the material is essential in organic 

aquatic plant production and, as 

petitioned, does not present adverse 

effects on humans or the environment. 

2. Is the substance compatible with a 

system of sustainable agriculture? 

[§6518(m)(7)]

X See #1

3. If used in livestock feed or pet food, Is 

the nutritional quality of the food 

maintained with the substance? 

[§205.600(b)(3)]

X

4. If used in livestock feed or pet food, Is 

the primary use as a preservative? 

[§205.600(b)(4)]

X

5. If used in livestock feed or pet food, Is 

the primary use to recreate or improve 

flavors, colors, textures, or nutritive value 

lost in processing (except when required 

by law)? [§205.600(b)(4)]

X
This is a proposal by a Subcommittee of the National Organic Standards Board (NOSB). Proposals are posted for public comment and 

then may be voted upon by the full Board. They are not final Board recommendations or NOP policy

Revised June 20 2013

6. Is the substance used in production, and 

does it contain an active synthetic 

ingredient in the following categories:

[§6517(c)(1)(B)(i);

copper and sulfur compounds

X

toxins derived from bacteria X

pheromones, soaps, horticultural oils, 

fish emulsions, treated seed, vitamins 

and minerals

X

livestock parasiticides and medicines X

production aids including netting, tree 

wraps and seals, insect traps, sticky 

barriers, row covers, and equipment 

cleansers

X

Minority Opinion - Chlorine Materials in Aquatic Plant Production

February 20, 2014

A minority of the subcommittee suggested that the subcommittee adopt an annotation motion 

for chlorine use in aquaculture for plants that set a 5-year expiration date on the listing, with a 

justification explaining that the specific time frame for an expiration date allows the Board to 

monitor the use of the material, update its scientific and essentiality review, incentivize 

alternatives and continuous improvement, and vote on the continuation of use pending the 

receipt of a petition requesting that use be extended.

Support for the annotation motion is based on the following justification: Since the petition for 

chlorine use in aquaculture certified organic is being considered in the absence of regulations 

defining acceptable defined practices in organic aquaculture, essentiality in particular cannot be 

judged at this time. Therefore, the NOSB needs to reconsider the approval in five years at the 

least. Current consideration of the material has raised issues relating to health or environmental 

impacts, especially relating to chlorine manufacture; alternatives under consideration by EPA’s 

Design for the Environment and the Toxics Use Reduction Institute; and compatibility with 

organic and sustainable agriculture. The review in 5 years provides an opportunity for the Board 

to reevaluate and vote for the continued or modified use of the material under the same 

standard of review that is used to approve the material during its petition review. 

In addition, the minority makes the following comments and additions to the majority checklist, 

which it believes does not provide a full assessment of environmental and health standards 

review required under the Organic Foods Production Act (OFPA): There are two separate uses 

covered by the petition – (1) disinfection of hard surfaces, and (2) disinfection of culture water. 

These two uses are distinct, and the distinction is blurred by the motion of the subcommittee. 

The use for disinfecting hard surfaces is similar to the allowed use in terrestrial crop production. 

It is specifically mentioned as a use included as a “production aid” in OFPA. Such use results in 

limited effluent, and the major difference between it and the current §601 listing is that 

aquaculture facilities are likely to be closer to water that could be contaminated by effluent. The 

use for disinfecting culture water, on the other hand, involves much greater quantities of water, 
This is a proposal by a Subcommittee of the National Organic Standards Board (NOSB). Proposals are posted for public comment and 

then may be voted upon by the full Board. They are not final Board recommendations or NOP policy

Revised June 20 2013

potentially larger discharges, and the possibility for spills into waterbodies. It is not a “production 

aid” use. The Technical Review (TR) does not address hazards associated with such a use in 

questions #4-8. Alternatives for the water disinfection use are not discussed in questions #12-

14. We cannot be sure what such a use would be in the aquaculture setting until we have 

aquaculture standards (for example, what is the agro-ecosystem in question?)

With regard to alternatives, there are now resources associated with “Green Chemistry” 

programs, such as the Toxics Use Reduction Institute at the University of Massachusetts in 

Lowell, and the Design for the Environment program at EPA that address chemical alternatives 

to chlorine as a disinfectant when such nonchemical approaches as steam are not appropriate. 

These need to be considered in evaluating alternatives. See, for example, the following 

websites: The Presidential Green Chemistry Challenge Awards Program p. 30 (p. 34 of pdf);

Overview of Design for the Environment, disinfectants p. 20; Green Product Certification and 

Labeling: Quick Reference.

Further, the petitioner has indicated that all materials petitioned for use in organic production of 

aquatic plants would be used only in closed systems. Therefore, an annotation should be added 

restricting the use of chlorine to closed systems with no discharge into natural waterbodies.

With regard to checklist Category 1, Adverse Impacts on Humans and the Environment, the 

minority believes the following need to be considered:

• Effluent standards are set under the Clean Water Act (CWA), so there is a disconnect 

between allowances under the SDWA and impacts on wildlife under the CWA. The 

SDWA standard of 4 mg/L is 363 times as high as the aquatic life protection criterion of 

11 ug/L set under the CWA.1 Neither, however, equates to the OFPA criterion of “no 

harm” and the fact that aquaculture systems are closer to water that could be 

contaminated by effluent than terrestrial agricultural systems raises unique concerns that 

require close scrutiny and not reliance on other standards for terrestrial production. 

• Misuse can kill plants and soil organisms and raise soil pH and kill fish and invertebrates 

(2011 Crops TR lines 386-390; 270-271)

• TRI data includes 5.7 million pounds of chlorine per year released by facilities making 

and using chlorine. (ATSDR Tox Profile p. 162)

• When mixed with organic materials (e.g., algae, dirt), hypochlorite produces 

trihalomethanes (THMs), which are carcinogenic. Currently, the maximum contaminant 

level (MCL) for total THMs is 0.080 mg/L (EPA 2009). (2011 Crops TR lines 277-280) 

Depending on the source of water, this could result in the presence of THMs in culture 

water and its concentration in algae when used to disinfect water. (Chloroform MSDS 

http://datasheets.scbt.com/sc-239527.pdf)

• Due to high reactivity, the petitioned substances do not persist in the environment. But 

many products are possible from reactions, and some may be persistent. This is 

particularly an issue for water disinfection. (2011 Crops TR lines 476-491)

• Human health effects of chlorine include burning, pain, inflammation, irritation to 

respiratory system, etc. (2011 Crops TR lines 496-514)

• Chlorine may harm the beneficials inherent in an aquaculture system when used to 

disinfect water, or when discharged. (2011 Crops TR, lines 270-271)

• Chlorine compounds are used to kill algae, an important part of the aquatic ecosystem. 

(2011 Crops TR, lines 62, 87)

 1 EPA Ambient Water Quality Criteria for Chlorine, 

http://water.epa.gov/scitech/swguidance/standards/upload/2001_10_12_criteria_ambientwqc_chlorine198

4.pdf
This is a proposal by a Subcommittee of the National Organic Standards Board (NOSB). Proposals are posted for public comment and 

then may be voted upon by the full Board. They are not final Board recommendations or NOP policy

Revised June 20 2013

With regard to checklist Category 2, Essentiality, the minority believes the following need to be 

considered:

• “[T]he following non-synthetic materials are allowed as drip irrigation cleaners and could 

be used on hard surfaces: acetic acid, vinegar, citric acid, and other naturally occurring 

acids.” (2011 Crops TR 519-520) 

• The petition does not describe any limitations of alternative substances. It simply states 

that the alternatives are not used. The petition also does not distinguish between the 

disinfection of equipment and water. Some alternatives may be useful for one and some 

the other.

• Other alternative substances are hydrogen peroxide, electrolyzed water, alcohols, 

peracetic acid, copper sulfate, and soap algaecides for hard surfaces. Ozone for water 

disinfection (2011 Crops TR 535-606) See EPA Green Chemistry award for 

alternatives.2

• For other practices, see Toxics Use Reduction Institute CleanerSolutions Database.3

Under Category 3, Compatibility, the minority points out the following:

• Chlorine does not enhance water life and properties; is not from renewable resources; 

and has negative impacts on biodiversity. (2011 Crops TR 270-271, 278-279, 349-352).

• Natural alternatives exist. (2011 Crops TR 270-271, 278-279, 349-352, 519-530)

• The use for culture water disinfection is not included in any of the OFPA categories of 

§6517(c)(1)(B)(i).

 2 The Presidential Green Chemistry Challenge Awards Program Summary of 2005 Award Entries and 

Recipients, p. 30. http://www.epa.gov/greenchemistry/pubs/docs/award_entries_and_recipients2005.pdf

Almost all traditional, widely used disinfecting and sanitizing products contain ingredients that are toxic or 

potentially toxic, are environmentally hazardous, or have a high potential for accidents. For example, 

oxidizing chemicals, such as hypochlorite, peracetic acid, hydrogen peroxide, ozone, and chlorine 

dioxide, kill microorganisms by indiscriminate oxidation of organic matter, potentially destroying 

antioxidants, nutrients, and vitamins while forming unknown or toxic byproducts, including cancer-causing 

free radicals. The non-oxidizing microbicidal quaternary ammonium compounds (QACs; other traditional 

disinfectants) inhibit butyl cholinesterase in blood plasma, liver, pancreas, and the white matter and are 

unsafe for use on fruits and vegetables because they leave large residues. 

Microcide uses ingredients listed by the FDA and EPA in volumes 21 and 40 of the Code of Federal 

Regulations (CFR) as biodegradable, generally recognized as safe (GRAS), food additives, safe, and/or 

nonpolluting. With these ingredients, Microcide develops broad-spectrum microbicidal products as 

alternatives to toxic and oxidizing chemicals for the food processing, personal care, and health industries. 

Their products use surface-active agents at low pH. Raising the pH diminishes the microbicidal 

properties, allowing safe environmental disposal and biodegradation of the products after use. These 

products selectively kill microorganisms on food-contact surfaces, on fresh fruits and vegetables, and on 

body parts (including mucosal and skin surfaces) without covalent chemical reactions. The technology 

presents alternative products safe for manufacturing, transportation, and use without accident potential. 

Two of Microcide’s products, PRO-SAN and PRO-SAN L, are EPA-registered pesticides. 3 http://www.turi.org/Our_Work/Cleaning_Laboratory/Does_It_Clean/CleanerSolutions_Database