Sunset 2021 

Meeting 2 - Review

Crops Substances §205.601, §205.602 

October 2019

Introduction

As part of the Sunset Process, the National Organic Program (NOP) announces substances on the 

National List of Allowed and Prohibited Substances (National List) that are coming up for sunset review 

by the National Organic Standard Board (NOSB). The following list announces substances that are on the 

National List for use in organic crop production that must be reviewed by the NOSB and renewed by the 

USDA before their sunset dates in 2021. This list provides the substance’s current status on the National 

List, use description, references to past technical reports, past NOSB actions, and regulatory history, as 

applicable. 

Request for Comments

Written public comments will be accepted through October 3, 2019 via www.regulations.gov. 

Comments received after that date may not be reviewed by the NOSB before the October meeting. 

NOSB October 2019 proposals and discussion documents Page 77 of 230
Sunset 2021 

Meeting 2 - Review

Crops Substances §205.601, §205.602 

October 2019

Note: With the exception of ferric phosphate and hydrogen chloride the materials included in this list 

are undergoing early sunset review as part of the November 18, 2016, NOSB recommendation on 

efficient workload re-organization. 

Reference: 205.601 Synthetic substances allowed for use in organic crop production.

Hydrogen peroxide (a)

Hydrogen peroxide (i)

Soaps, ammonium

Oils, horticultural (e)

Oils, horticultural (i)

Pheromones

Ferric phosphate

Potassium bicarbonate

Magnesium sulfate

Hydrogen chloride

 

Reference: 205.602 Nonsynthetic substances prohibited for use in organic crop production.

Ash from manure burning

Sodium fluoaluminate

NOSB October 2019 proposals and discussion documents Page 78 of 230
Hydrogen peroxide—§205.601(a)

§205.601 Synthetic substances allowed for use in organic crop production.

Reference: 205.601(a) As algicide, disinfectants, and sanitizer, including irrigation system cleaning 

systems. (4) Hydrogen peroxide.

Technical Report(s): 1995 TAP; 2015 TR

Petition(s): N/A

Past NOSB Actions: 10/1995 NOSB minutes and vote; 11/2005 sunset recommendation -deferred; 

06/2006 sunset recommendation; 10/2010 sunset recommendation

10/2015 sunset recommendation

Recent Regulatory Background: Sunset renewal notice published 06/06/12 (77 FR 33290); Renewed 

03/15/2017 (82 FR 14420) 

Sunset Date: 3/15/2022 

Subcommittee Review:

Hydrogen peroxide is widely used as a disinfectant and bleaching agent. It is an effective and an 

environmentally benign substance used to reduce and control microorganisms for food safety purposes. 

It is critical for sanitizing aseptic packaging. It is a weak acid but a strong oxidizer and this makes it very 

useful as a fungicide, cleaning agent, and for disease control. 

Hydrogen peroxide is a very simple molecule with a formula of H2O2. Virtually all modern production 

facilities manufacture commercial hydrogen peroxide solutions using large, strategically located 

anthraquinone autoxidation processes. Improved production methods and facilities based on the 

anthraquinone (AO) process have recently appeared in the commercial patent literature. 

Hydrogen peroxide is a naturally occurring inorganic compound; however, the sources of hydrogen 

peroxide used in commercial fungicides, disinfectants and antiseptic products are produced through 

chemical synthesis. Industrial methods for the preparation of hydrogen peroxide are categorized as 

oxidation-reduction reactions. Modern commercial methods for hydrogen peroxide synthesis involve 

the transition-metal catalyzed chemical reduction of an alkyl anthraquinone with hydrogen (H2) gas to 

the corresponding hydroquinone followed by regenerative oxidation of the latter species in air.

Contamination is not expected when purified forms of hydrogen peroxide are released to the 

environment following normal use. At typical pesticide concentrations, hydrogen peroxide is expected 

to rapidly degrade to oxygen gas and water (US EPA, 2007). Large-volume spills and other releases of 

concentrated hydrogen peroxide could present a fire hazard since the substance readily decomposes to 

release oxygen gas. Pure hydrogen peroxide is not flammable and can be diluted with clean water to 

minimize the risk of fire. Although concentrated hydrogen peroxide is nonflammable, it is a powerful 

oxidizing agent that may spontaneously combust on contact with organic material and becomes 

explosive when heated. Combustion reactions and explosions resulting from accidental spills of 

concentrated hydrogen peroxide could therefore lead to environmental degradation.

A Technical Report (TR) was commissioned in 2015 for hydrogen peroxide since the information from 

the previous 1995 TAP was old and incomplete. It showed that hydrogen peroxide is inherently unstable 

and breaks down readily into oxygen and water. (TR Evaluation question 3-5). While it is toxic to disease 

spores and cells on contact, it has absolutely no residual effect. It has low or no impacts on birds, 

humans, or fish if it is used according to the label and protective application measures are taken. There 

can be some effects on soil microbiota in the very top layer of soil where it may come in contact, but 

because it breaks down so quickly, soil life is quickly restored. (TR 2015 Evaluation Question #8). 

NOSB October 2019 proposals and discussion documents Page 79 of 230
While there are some alternatives on the National List for sanitizers and disinfectants, as well as some 

essential oils with antiseptic properties, the National List items are not necessarily any better or safer 

than hydrogen peroxide, and the essential oils have not been studied to compare with Hydrogen 

peroxide side-by side to see if they are equally as effective and benign. (TR Evaluation question 11). 

Certain bacterial and fungal products that are beneficial in controlling plant diseases may be valid 

alternatives for some uses as a fungicide, but often these are best used as preventatives and are not 

effective once a disease has taken hold, and they are not good substitutes in all situations. Likewise, 

some biological, cultural and physical methods keep the need for use of hydrogen peroxide to a 

minimum, but don't apply to every situation. (TR Evaluation question 12). 

In the 2015 sunset review most public comment supported keeping hydrogen peroxide on the National 

List. It was frequently mentioned that it is one of the few tools left against fire blight now that 

antibiotics cannot be used. It is widely used to clean equipment, in mushroom production, and to 

alternate with other materials for resistance management. No comments were put forward with new 

information that would contribute to the OFPA criteria review. The NOSB found the material to meet 

OFPA criteria and had no objection to continued listing. No significant new issues were raised by the 

public. 

During the Spring 2019 NOSB meeting the Crops Committee received comments in favor of relisting 

hydrogen peroxide and no comments against relisting. Comments included the following:

• Hydrogen peroxide is an effective microbial pesticide used in the orchard setting for the 

sanitation of equipment such as picking bags and pruning shears. It is also used as an algicide 

and disinfectant, including for irrigation system cleaning. 

• With the loss of antibiotics, hydrogen peroxide has become an extremely important tool in 

controlling fire blight in both organic apples and pears. 

Subcommittee Vote:

Motion to remove hydrogen peroxide from §205.601(a) of the National List based on the following 

criteria in the Organic Foods Production Act (OFPA) and/or 7 CFR 205.600(b): NA

Motion by: Jesse Buie

Seconded by: Harriet Behar

Yes: 0 No: 8 Abstain: 0 Absent: 0 Recuse: 0

Hydrogen peroxide—§205.601(i)

§205.601 Synthetic substances allowed for use in organic crop production.

Reference: 205.601(i) As plant disease control. (5) Hydrogen peroxide.

Technical Report(s): 1995 TAP; 2015 TR

Petition(s): N/A

Past NOSB Actions: 10/1995 NOSB minutes and vote; 11/2005 sunset recommendation -deferred; 

06/2006 sunset recommendation; 10/2010 sunset recommendation

10/2015 sunset recommendation

Recent Regulatory Background: Sunset renewal notice published 06/06/12 (77 FR 33290); Renewed 

03/15/2017 (82 FR 14420) 

Sunset Date: 3/15/2022 

Subcommittee Review:

Hydrogen peroxide is widely used as a disinfectant and bleaching agent. It is an effective and an 

environmentally benign substance used to reduce and control microorganisms for food safety purposes. 

NOSB October 2019 proposals and discussion documents Page 80 of 230
It is critical for sanitizing aseptic packaging. It is a weak acid but a strong oxidizer and this makes it very 

useful as a fungicide, cleaning agent, and for disease control. 

Hydrogen peroxide is a very simple molecule with a formula of H2O2. Virtually all modern production 

facilities manufacture commercial hydrogen peroxide solutions using large, strategically located 

anthraquinone autoxidation processes. Improved production methods and facilities based on the 

anthraquinone (AO) process have recently appeared in the commercial patent literature. 

Hydrogen peroxide is a naturally occurring inorganic compound; however, the sources of hydrogen 

peroxide used in commercial fungicides, disinfectants and antiseptic products are produced through 

chemical synthesis. Industrial methods for the preparation of hydrogen peroxide are categorized as 

oxidation-reduction reactions. Modern commercial methods for hydrogen peroxide synthesis involve 

the transition-metal catalyzed chemical reduction of an alkyl anthraquinone with hydrogen (H2) gas to 

the corresponding hydroquinone followed by regenerative oxidation of the latter species in air.

Contamination is not expected when purified forms of hydrogen peroxide are released to the 

environment following normal use. At typical pesticide concentrations, hydrogen peroxide is expected 

to rapidly degrade to oxygen gas and water (US EPA, 2007). Large-volume spills and other releases of 

concentrated hydrogen peroxide could present a fire hazard since the substance readily decomposes to 

release oxygen gas. Pure hydrogen peroxide is not flammable and can be diluted with clean water to 

minimize the risk of fire. Although concentrated hydrogen peroxide is nonflammable, it is a powerful 

oxidizing agent that may spontaneously combust on contact with organic material and becomes 

explosive when heated. Combustion reactions and explosions resulting from accidental spills of 

concentrated hydrogen peroxide could therefore lead to environmental degradation.

A Technical Report (TR) was commissioned in 2015 for hydrogen peroxide since the information from 

the previous 1995 TAP was old and incomplete. It showed that hydrogen peroxide is inherently unstable 

and breaks down readily into oxygen and water. (TR Evaluation question 3-5). While it is toxic to disease 

spores and cells on contact, it has absolutely no residual effect. It has low or no impacts on birds, 

humans, or fish if it is used according to the label and protective application measures are taken. There 

can be some effects on soil microbiota in the very top layer of soil where it may come in contact, but 

because it breaks down so quickly, soil life is quickly restored. (TR 2015 Evaluation Question #8). 

While there are some alternatives on the National List for sanitizers and disinfectants, as well as some 

essential oils with antiseptic properties, the National List items are not necessarily any better or safer 

than hydrogen peroxide, and the essential oils have not been studied to compare with Hydrogen

peroxide side-by side to see if they are equally as effective and benign. (TR Evaluation question 11). 

Certain bacterial and fungal products that are beneficial in controlling plant diseases may be valid 

alternatives for some uses as a fungicide, but often these are best used as preventatives and are not 

effective once a disease has taken hold, and they are not good substitutes in all situations. Likewise, 

some biological, cultural and physical methods keep the need for use of hydrogen peroxide to a 

minimum, but don't apply to every situation. (TR Evaluation question 12). 

In the 2015 sunset review most public comment supported keeping hydrogen peroxide on the National 

List. It was frequently mentioned that it is one of the few tools left against fire blight now that 

antibiotics cannot be used. It is widely used to clean equipment, in mushroom production, and to 

alternate with other materials for resistance management. No comments were put forward with new 

information that would contribute to the OFPA criteria review. The NOSB found the material to meet 

OFPA criteria and had no objection to continued listing. No significant new issues were raised by the 

public. 

NOSB October 2019 proposals and discussion documents Page 81 of 230
During the Spring 2019 NOSB meeting the Crops Committee received comments in favor of relisting

hydrogen peroxide and no comments against relisting. Comments included the following:

• Hydrogen peroxide is an effective microbial pesticide used in the orchard setting for the 

sanitation of equipment such as picking bags and pruning shears. It is also used as an algicide 

and disinfectant, including for irrigation system cleaning. 

• With the loss of antibiotics, hydrogen peroxide has become an extremely important tool in 

controlling fire blight in both organic apples and pears. 

Subcommittee Vote:

Motion to remove hydrogen peroxide from §205.601(a) of the National List based on the following 

criteria in the Organic Foods Production Act (OFPA) and/or 7 CFR 205.600(b): NA

Motion by: Jesse Buie

Seconded by: Harriet Behar

Yes: 0 No: 8 Abstain: 0 Absent: 0 Recuse: 0

Soaps, ammonium

§205.601 Synthetic substances allowed for use in organic crop production.

Reference: 205.601(d) As animal repellents—Soaps, ammonium—for use as a large animal repellant 

only, no contact with soil or edible portion of crop. 

Technical Report: 1996 TAP; 2019 TR

Petition(s): N/A

Past NOSB Actions: 10/1995 NOSB minutes and vote; 11/2005 sunset recommendation; 10/2010 

sunset recommendation; 10/2015 sunset recommendation

Recent Regulatory Background: Sunset renewal notice published 06/06/12 (77 FR 33290); Renewed 

03/15/2017 (82 FR 14420)

Sunset Date: 3/15/2022 

Subcommittee Review:

Ammonium soaps are used as animal repellents to protect organically produced crops from unwanted 

browsing, primarily from deer and rabbits. USDA organic regulations allow ammonium soaps as a 

"synthetic substance allowed for use in organic crop production" at 7 CFR 205.601.

Ammonium soaps are manufactured by hydrolysis of fats (triglycerides) with an alkaline source in a 

saponification process. In this process, the base reacts with the fatty ester to break the ester linkages, 

resulting in the formation of a salt with the cation of the base and the carboxylate anion that remains at 

the end of the hydrolysis. A wide range of fats may be used in the saponification process, including both 

plant and animal fats. Because of the relative abundance of fats and their low cost, most soaps are 

produced by the saponification of natural fats. Ammonium cations also exist in nature and play an 

important role in the metabolic pathways of a range of organisms , as well as being a key component of 

the nitrogen cycle. Soaps, however, do not naturally exist in nature but are manufactured.

Ammonium soaps are permitted by the Canadian General Standards Board Permitted Substances List - 

Ammonium soaps are listed in the CAN/CGSB-32.311-2015 - Organic production systems - permitted 

substances lists.

Studies conducted by the EPA estimate that ammonium soaps will undergo rapid degradation in the 

environment, primarily through microbial metabolism, yielding an environmental half-life of less than 

one day. Interesting to note that the toxicological profile of the substance differs based on the 

environment in which it is located. They are regarded as having low toxicity to terrestrial organisms, 

NOSB October 2019 proposals and discussion documents Page 82 of 230
with little impact to mammals and avian animals. The EPA has placed them in Toxicity Category IV, the 

lowest available classification. They are, however, moderately toxic in aquatic environments. 

Ammonium soaps have been classified as "highly toxic" to crustaceans by the EPA. Due to the potential 

toxicity to aquatic environments, ammonium soap repellent product labels stipulate "This product may 

be hazardous to aquatic invertebrates. Do not apply to water bodies such as ponds or creeks.

The EPA has given ammonium soaps the lowest possible toxicity classification (Toxicity Category IV). 

They have also concluded that the oral intake of dangerous levels of the substance is highly unlikely due 

to the recognizable and undesirable soap taste. Despite the low toxicity of ammonium soaps there are 

some health risks. They are primarily irritation-based. Occasional skin irritation upon prolonged 

exposure has been reported as potential problems with direct exposure in the eye.

There are some alternative methods that make the use of ammonium soaps unnecessary. They include 

population control of animals, alteration of habitat or physical barriers. As such, fencing is widely 

acknowledged as the most effective means of preventing crop damage from unintended browsing.

There are also natural (non-synthetic) substances which may be used in place of ammonium soaps. 

These all to have similar limitations to the soaps and include fear-based area repellents such as coyote 

urine, smell-based area repellents such as human hair and contact repellents that include capsaicin and 

black pepper oil.

There were approximately 10 comments all supporting the continued listing of ammonium soaps on the 

National List of Allowed and Prohibited Substances. No comments for removal were received.

Subcommittee Vote: 

Motion to remove soaps, ammonium, from §205.601 of the National List based on the following criteria 

in the Organic Foods Production Act (OFPA) and/or 7CFR205.600(b): NA

Motion by: Rick Greenwood

Seconded by: Emily Oakley

Yes: 0 No: 7 Abstain: 0 Absent: 1 Recuse: 0

Oils, horticultural—§205.601(e)

§205.601 Synthetic substances allowed for use in organic crop production.

Reference: 205.601(e) As insecticides (including acaricides or mite control). (7) Oils, horticultural—

narrow range oils as dormant, suffocating, and summer oils.

Technical Report: 1995 TAP; 2019 TR 

Petition(s): N/A

Past NOSB Actions: 04/1995 NOSB minutes and vote; 11/2005 sunset recommendation – 

deferred; 06/2006 sunset recommendation; 10/2010 sunset recommendation; 10/2015 sunset 

recommendation

Recent Regulatory Background: Sunset renewal notice published 06/06/12 (77 FR 33290); Renewed 

03/15/2017 (82 FR 14420) 

Sunset Date: 3/15/2022 

Subcommittee Review:

Horticultural oils have widespread use in organic fruit and vegetable production. They can be used in 

nearly every season and may be used alone or in mixes that include other nutrient or pest control 

products. Oils may be used for control of multiple plant diseases as well as acaricides, miticides, and 

NOSB October 2019 proposals and discussion documents Page 83 of 230
insecticides. According to the 2018 technical report (TR), oils have different modes of action on insects, 

mites and plant pathogens. They target multiple sites and not specific receptors and thus do not act like 

most synthetic insecticides. This action also helps to prevent resistance to their action. The multiple 

actions include smothering insect eggs by preventing atmospheric gas exchange, softening or disrupting 

insect cuticles, interfering with molting, as well as altering behaviors such as egg laying.

Horticultural oils may be called by many different names; however, the 2018 TR generally refers to them 

as petroleum-derived spray oils (PDSO’s) or mineral oils. Their use has increased and has been refined 

over the last century. Recognition that different fractions of oils have higher efficacy for pest control 

and that the range of phytotoxic effects on the plant goes from none to high depending on the fraction 

used led to the selection of a narrow range of oils exhibiting the dual characteristics of being effective 

against pests and non-toxic to plants. They are often classified by boiling point, although modern 

terminology may refer to many other characteristics such as chain length and chemical structure (2018 

TR).

Most PDSOs are produced from the extraction, distillation, and further refinement of petroleum. The 

2018 TR describes in detail the potential processes by which crude petroleum may be transformed to a 

narrow range horticultural oil. In general, the crude petroleum may be converted chemically by either 

catalytic or thermal methods. Once the oils are converted to a certain fraction, additional chemical 

treatments are applied to the distillates to remove phytotoxic compounds, such as sulfur, while keeping 

compounds toxic to pests and diseases. Additionally, the 2018 TR states horticultural oils are often 

formulated with wetting agents or surfactants that allow them to be mixed and diluted with water. Most 

spray oils in the United States contain a non-ionic surfactant dissolved in the oil concentrate at a 

concentration of 0.35 percent for citrus use and 0.5 percent for deciduous use.

The exploration and extraction of petroleum has a number of environmental effects that include land 

use issues, spills, emissions, pipeline and infrastructure construction, among others. However, once the 

oil is refined and applied as a pest control material, the environmental impact of these oils decreases. 

The EPA exempts petroleum oils, or mineral oil, from the requirement of a tolerance when applied to 

growing crops [40 CFR 180.905]. The 2018 TR cites a number of studies that show that actual 

persistence in the field is highly variable and depends on many factors including temperature, 

precipitation, sunlight, how the oil is applied, and droplet size. Soil biota degrade these oils over time 

with the amount of time necessary for degradation dependent on many environmental factors. Various 

grasses and legumes may also be an effective means of removing petroleum hydrocarbons from the soil. 

The effect of spray oils on non-target beneficial organisms varies based on the mobility of the organism, 

its stage of development, and its ability to reinvade after the oil application (2018 TR). The timing of the 

oil application may also alter the effects on beneficial organisms. For example, dormant applications of 

oil may be applied before beneficial organisms become active. Even where oil is applied repeatedly and 

in the non-dormant season, excellent biocontrol may still be achieved in organic systems. In general, 

non-dormant application rates are lower than dormant rates in order to prevent plant phytotoxicity. 

These lower rates may also limit the negative effects on biocontrol agents. Various studies have 

confirmed that the use of oils is compatible with integrated pest management systems (2018 TR).

Horticultural oils form the basis for many organic pest control systems. They may prevent the need for 

higher toxicity insecticides and keep pest populations below economic thresholds. They are widely used 

in organic tree fruits, traditionally in the dormant season, and more recently, throughout the growing 

season. They may be used alone or in combination with other materials - the use of oil in these 

combinations may help increase the activity of the other material through the “spreading” action of the

oil in addition to the pest control effect of the oil itself. 

NOSB October 2019 proposals and discussion documents Page 84 of 230
Materials such as kaolin, botanical insecticides and plant-based oils may also be alternative to oils. 

Kaolin may be effective in certain cases but does not have the spectrum of activity that oils do. 

Botanical insecticides may disrupt biocontrol programs. Other plant-based oils may be alternatives to 

petroleum-based oils, however, they are not widely used and may not be widely available. The 2018 TR 

notes a number of alternatives and cites one study that showed that castor, cottonseed, and linseed oils 

had comparable or better activity than petroleum oils against scales, but the vegetable oils were also 

more phytotoxic to the plants. Some studies show that plant-based oils may be superior to PDSO’s in 

pest controls, while others indicate lower efficacy. 

Biopesticides may also have efficacy against target pests. These include a number of different fungi, 

bacteria and viruses such as codling moth granulosis virus, Chromobacterium subtsuga, and Bacillus 

thuringiensis (Bt). Oils may target a variety of pests while these various biopesticides either target a 

single pest species or a limited range of pest species. Additionally, these biocontrol agents may be 

applied at different timings than oils and may work better when used in conjunction with oils rather 

than as alternatives (2018 TR). 

Previous sunset reviews included discussions around whether vegetable oils could serve as a natural 

replacement for the horticultural oils. During those discussions it was discovered that vegetable oils 

contained synthetic emulsifiers (mainly derived from a petroleum base), that if excluded, would prevent 

the oils from working properly. Both vegetable and horticultural oils require the addition of emulsifiers

to allow them to stay in suspension when added to water for application to the targeted crop. It was 

also determined that the vegetable oils would not control certain pests adequately compared to the 

horticultural spray oils. 

In past sunset reviews there has been overwhelming support for the continued listing of this material. 

Organic stakeholders provided a clear message to the full NOSB that this material remains a necessary 

tool in organic crop production and in fact has increased in use due to the recent growth of organic 

production. It was also pointed out during public comment that these oils are allowed for use worldwide by most organic certifying bodies for use in organic crop production.

Public comments during the Spring 2019 NOSB meeting echoed earlier comments. Many commenters 

noted the extensive benefits and need for these oils. One commenter noted that there is no known 

alternative for control of bugs in soybean fields. Another noted that while other types of oils are 

available, they will not work in place of horticultural spray oils. They continued by saying that other oils, 

such as fish or vegetable oils, can be phytotoxic to the foliage or fruit/crop itself and can have 

compatibility issues with other materials used in organic production. One comment was received asking 

for an annotation that would protect workers from inhalation hazards and nontarget arthropods from 

harm and if that annotation is not possible that the oils should be delisted. Other than that comment, 

there was broad support for the relisting of horticultural oils.

Subcommittee Vote:

Motion to remove horticultural oils from §205.601(e) of the National List based on the following criteria 

in the Organic Foods Production Act (OFPA) and/or 7 CFR 205.600(b): NA

Motion by: Steve Ela

Seconded by: Dave Mortenson

Yes: 0 No: 8 Abstain: Absent: 0 Recuse: 0

NOSB October 2019 proposals and discussion documents Page 85 of 230
Oils, horticultural—§205.601(i)

§205.601 Synthetic substances allowed for use in organic crop production.

Reference: 205.601(i) As plant disease control. (7) Oils, horticultural—narrow range oils as dormant, 

suffocating, and summer oils.

Technical Report: 1995 TAP; 2019 TR 

Petition(s): N/A

Past NOSB Actions: 04/1995 NOSB minutes and vote; 11/2005 sunset recommendation – deferred; 

06/2006 sunset recommendation; 10/2010 sunset recommendation; 10/2015 sunset recommendation

Recent Regulatory Background: Sunset renewal notice published 06/06/12 (77 FR 33290); Renewed 

03/15/2017 (82 FR 14420) 

Sunset Date: 3/15/2022 

Subcommittee Review:

Horticultural oils have widespread use in organic fruit and vegetable production. They can be used in 

nearly every season and may be used alone or in mixes that include other nutrient or pest control 

products. Oils may be used for control of multiple plant diseases as well as acaricides, miticides, and 

insecticides. According to the 2018 technical report (TR), oils have different modes of action on insects, 

mites and plant pathogens. They target multiple sites and not specific receptors and thus do not act like 

most synthetic insecticides. This action also helps to prevent resistance to their action. The multiple 

actions include smothering insect eggs by preventing atmospheric gas exchange, softening or disrupting 

insect cuticles, interfering with molting, as well as altering behaviors such as egg laying.

Horticultural oils may be called by many different names; however, the 2018 TR generally refers to them 

as petroleum-derived spray oils (PDSO’s) or mineral oils. Their use has increased and has been refined 

over the last century. Recognition that different fractions of oils have higher efficacy for pest control 

and that the range of phytotoxic effects on the plant goes from none to high depending on the fraction 

used led to the selection of a narrow range of oils exhibiting the dual characteristics of being effective 

against pests and non-toxic to plants. They are often classified by boiling point, although modern 

terminology may refer to many other characteristics such as chain length and chemical structure (2018 

TR).

Most PDSOs are produced from the extraction, distillation, and further refinement of petroleum. The 

2018 TR describes in detail the potential processes by which crude petroleum may be transformed to a 

narrow range horticultural oil. In general, the crude petroleum may be converted chemically by either 

catalytic or thermal methods. Once the oils are converted to a certain fraction, additional chemical 

treatments are applied to the distillates to remove phytotoxic compounds, such as sulfur, while keeping 

compounds toxic to pests and diseases. Additionally, the 2018 TR states horticultural oils are often 

formulated with wetting agents or surfactants that allow them to be mixed and diluted with water. Most 

spray oils in the United States contain a non-ionic surfactant dissolved in the oil concentrate at a 

concentration of 0.35 percent for citrus use and 0.5 percent for deciduous use.

The exploration and extraction of petroleum has a number of environmental effects that include land 

use issues, spills, emissions, pipeline and infrastructure construction, among others. However, once the 

oil is refined and applied as a pest control material, the environmental impact of these oils decreases. 

The EPA exempts petroleum oils, or mineral oil, from the requirement of a tolerance when applied to 

growing crops [40 CFR 180.905]. The 2018 TR cites a number of studies that show that actual 

persistence in the field is highly variable and depends on many factors including temperature, 

precipitation, sunlight, how the oil is applied, and droplet size. Soil biota degrade these oils over time 

NOSB October 2019 proposals and discussion documents Page 86 of 230
with the amount of time necessary for degradation dependent on many environmental factors. Various 

grasses and legumes may also be an effective means of removing petroleum hydrocarbons from the soil. 

The effect of spray oils on non-target beneficial organisms varies based on the mobility of the organism, 

its stage of development, and its ability to reinvade after the oil application (2018 TR). The timing of the 

oil application may also alter the effects on beneficial organisms. For example, dormant applications of 

oil may be applied before beneficial organisms become active. Even where oil is applied repeatedly and 

in the non-dormant season, excellent biocontrol may still be achieved in organic systems. In general, 

non-dormant application rates are lower than dormant rates in order to prevent plant phytotoxicity. 

These lower rates may also limit the negative effects on biocontrol agents. Various studies have 

confirmed that the use of oils is compatible with integrated pest management systems (2018 TR).

Horticultural oils form the basis for many organic pest control systems. They may prevent the need for 

higher toxicity insecticides and keep pest populations below economic thresholds. They are widely used 

in organic tree fruits, traditionally in the dormant season, and more recently, throughout the growing 

season. They may be used alone or in combination with other materials - the use of oil in these 

combinations may help increase the activity of the other material through the “spreading” action of the 

oil in addition to the pest control effect of the oil itself. 

Materials such as kaolin, botanical insecticides and plant-based oils may also be alternative to oils. 

Kaolin may be effective in certain cases but does not have the spectrum of activity that oils do. 

Botanical insecticides may disrupt biocontrol programs. Other plant-based oils may be alternatives to 

petroleum-based oils, however, they are not widely used and may not be widely available. The 2018 TR 

notes a number of alternatives and cites one study that showed that castor, cottonseed, and linseed oils 

had comparable or better activity than petroleum oils against scales, but the vegetable oils were also 

more phytotoxic to the plants. Some studies show that plant-based oils may be superior to PDSO’s in 

pest controls, while others indicate lower efficacy. 

Biopesticides may also have efficacy against target pests. These include a number of different fungi, 

bacteria and viruses such as codling moth granulosis virus, Chromobacterium subtsuga, and Bacillus 

thuringiensis (Bt). Oils may target a variety of pests while these various biopesticides either target a 

single pest species or a limited range of pest species. Additionally, these biocontrol agents may be 

applied at different timings than oils and may work better when used in conjunction with oils rather 

than as alternatives (2018 TR). 

Previous sunset reviews included discussions around whether vegetable oils could serve as a natural 

replacement for the horticultural oils. During those discussions it was discovered that vegetable oils 

contained synthetic emulsifiers (mainly derived from a petroleum base), that if excluded, would prevent 

the oils from working properly. Both vegetable and horticultural oils require the addition of emulsifiers 

to allow them to stay in suspension when added to water for application to the targeted crop. It was 

also determined that the vegetable oils would not control certain pests adequately compared to the 

horticultural spray oils. 

In past sunset reviews there has been overwhelming support for the continued listing of this material. 

Organic stakeholders provided a clear message to the full NOSB that this material remains a necessary 

tool in organic crop production and in fact has increased in use due to the recent growth of organic 

production. It was also pointed out during public comment that these oils are allowed for use worldwide by most organic certifying bodies for use in organic crop production.

Public comments during the Spring 2019 NOSB meeting echoed earlier comments. Many commenters 

noted the extensive benefits and need for these oils. One commenter noted that there is no known 

NOSB October 2019 proposals and discussion documents Page 87 of 230
alternative for control of bugs in soybean fields. Another noted that while other types of oils are 

available, they will not work in place of horticultural spray oils. They continued by saying that other oils, 

such as fish or vegetable oils, can be phytotoxic to the foliage or fruit/crop itself and can have 

compatibility issues with other materials used in organic production. One comment was received asking 

for an annotation that would protect workers from inhalation hazards and nontarget arthropods from 

harm and if that annotation is not possible that the oils should be delisted. Other than that comment, 

there was broad support for the relisting of horticultural oils.

Subcommittee Vote:

Motion to remove horticultural oils from §205.601(i) of the National List based on the following criteria 

in the Organic Foods Production Act (OFPA) and/or 7 CFR 205.600(b): NA

Motion by: Steve Ela

Seconded by: Harriet Behar

Yes: 0 No: 8 Abstain: 0 Absent: 0 Recuse: 0

Pheromones

§205.601 Synthetic substances allowed for use in organic crop production.

Reference: 205.601(f) As insect management. Pheromones.

Technical Report: 1995 TAP; 2012 TR

Petition(s): N/A

Past NOSB Actions: 04/1995 NOSB minutes and vote; 11/2005 sunset recommendation; 10/2010 sunset 

recommendation; 10/2015 sunset recommendation

Recent Regulatory Background: Sunset renewal notice published 06/06/12 (77 FR 33290); Renewed 

03/15/2017 (82 FR 14420) 

Sunset Date: 3/15/2022 

Subcommittee Review:

Pheromones are volatile chemicals produced in nature by a given species to communicate with other 

individuals of the same species to affect their behavior. Pheromones are produced naturally by many 

organisms and are synthetically produced for use in agriculture. Insect pheromones are generally 

comprised of very specific esters, that alone, or in combination, create a species-specific communication 

system. Pheromones may be released from various types of dispensers into the surrounding air. Inert 

ingredients may be used as part of the formulation process but generally do not contact crops since they 

are contained within the dispensers. Pheromones are considered generally non-toxic and have a low 

persistence in the environment. 

Pheromones are used by organic (and many conventional) crop producers and are especially important 

for organic tree fruit production. Pheromones are used by growers in a variety of ways such as 

monitoring insect presence and population density, mass trapping, ‘attract and kill’ systems, and for use 

in mating disruption or confusion. 

The use of pheromones to attract insects to traps has long been used as a means of monitoring 

populations, determining whether controls need to be applied, and infer the timing of controls 

applications. Varying types of dispensers are impregnated with the pheromone and then placed in some 

sort of monitoring trap. Trapping can field check insect development models as well as be used to 

determine when a threshold has been reached that might require further action by a farmer. Mass 

trapping using pheromones as an attractant can also be used to help in reducing the overall numbers of 

NOSB October 2019 proposals and discussion documents Page 88 of 230
an insect pest. A variant of mass trapping is the attract and kill system. Rather than trapping the insect, 

these systems use the synthetic pheromone as an attractant to get the insect to come into contact with 

an insecticide.

Mating disruption/confusion uses a synthetic pheromone to saturate a targeted area. The male of the 

targeted species is unable to differentiate between the pheromone released by the female and that 

applied by dispensers. This can cause the male to become confused and disoriented and thus unable to 

locate the species female for mating. Normally in organic crop production these pheromones are 

dispersed for use via a passive or active pheromone dispenser (including traps and lures). Some forms of 

passive dispensers are pheromone-impregnated polymer spirals, ropes, coils, twist ties, or tubes. The 

use of wires, clips, or circular tubes allows these pheromone dispensers to be placed directly in the 

intended area of usage. Active dispensers, commonly called puffers, distribute a larger amount of 

pheromone on a programmed schedule. They are usually used at lower densities than passive 

dispensers and can be programmed to only release pheromone when the target insect might be active. 

As the 2012 technical report notes, while pheromones are produced naturally by insects and other 

organisms, they are difficult to isolate in sufficient quantities for commercial production. Thus, most 

commercially used pheromones are synthetically produced and attempt to replicate the natural 

pheromone. The synthesis of the pheromones is complex and normally involves a number of conversion 

steps.

The TR further cites various studies showing that insect pheromones are generally comprised of very 

specific esters. These esters vary in carbon chain length. The primary components of sex pheromones 

(esters) are the most critical part of the chemical complex, but are reliant on the presence or absence of 

secondary components, which greatly affect an insect’s response sequence. 

During past reviews there has been concern raised over the inerts used in pheromones because they do 

include known irritants, sensitizers, and allergens. The 2012 TR mentions that some compounds could 

potentially be linked to asthma, cancer, or endocrine disruption. However, under the current use of 

pheromones it is not believed that they would release enough volume to leave any kind of residue on 

the agricultural crops being treated. It also states that dissipation takes place via volatilization and 

degradation, rapidly into the environment. 

In past reviews, some concerns were raised around the use of “encapsulated pheromones” (those 

concerns mentioned harm to honey bees and concerns over aerial applications). These involve small 

pheromone containing capsules that might be applied in water or by air and could have direct crop 

contact. However, use of these forms of pheromones has not generally reached commercial 

application. 

The 2012 TR notes that based on low observed toxicity in animal testing, and expected low exposure to 

humans, there is no risk to human health expected from the use of pheromones. EPA data shows that 

no human health concerns had been reported in the ten years prior to the TR.

Pheromones continue to be an integral and highly used component of organic agriculture. Their use in 

trapping and monitoring provides a basis for integrated pest management and helps to ensure that 

other pest control materials are only applied where and when needed. For certain pests in organic 

systems their use in mating disruption may be the only viable control option and in other systems their 

use precludes the need for more disruptive control options.

NOSB October 2019 proposals and discussion documents Page 89 of 230
Public comments from previous sunset reviews have been strongly supportive of the relisting of 

pheromones. Other commenters have noted that their delisting would lead to the loss of many acres of 

organic tree fruits. Comments noted that the use of pheromones in organic crop production has 

continued to increase, as various formulations have been developed for specific target species.

Public comments received during the Spring 2019 NOSB meeting were in favor of relisting pheromones. 

There were many comments noting their widespread use, insect specificity, use in monitoring 

populations, and benign nature. Several commenters did support relisting with the caveat that the 

pheromones are identical to or substantially similar to natural pheromones, in passive dispensers, 

without added toxicants and with only approved inert ingredients. There is currently no annotation for 

pheromones, but comments received indicate that their use generally fits this request. 

Microencapsulated pheromones which might be sprayed and have direct fruit contact have not become 

commercially available. Active dispensers (also known as puffers) are in current use, but act in similar 

fashion to the passive dispensers in terms of fruit contact or type of pheromone used. 

Subcommittee Vote:

Motion to remove pheromones from §205.601(f) of the National List based on the following criteria in 

the Organic Foods Production Act (OFPA) and/or 7 CFR 205.600(b): NA

Motion by: Steve Ela

Seconded by: Dave Mortenson

Yes: 0 No: 8 Abstain: 0 Absent: 0 Recuse: 0

Ferric phosphate

§205.601 Synthetic substances allowed for use in organic crop production.

Reference: §205.601(h) As slug or snail bait. Ferric phosphate (CAS #s 10045-86-0).

Technical Report: 2004 TAP, 2010 TR, Supplemental TR 2012

Petition(s): 05/2003 , Supplemental Information 02/2005, Petition to remove: 07/2009

Past NOSB Actions: 03/2005 sunset recommendation; 04/2010 sunset recommendation; 10/2012 

recommendation on petition to remove from national list; XX/2016 sunset recommendation

Recent Regulatory Background: Added to National List 09/11/06 71 FR 53299; Renewed 08/03/2011 76 FR 

46595; Renewed 09/12/16 81 FR 8821

Sunset Date: 9/12/2021

Subcommittee Review:

Use

Ferric phosphate is used as a molluscicide for slug and snail suppression. Ferric phosphate accumulates in 

the calcium spherules of slug and snail digestive glands, thereby interfering with calcium metabolism, and 

in turn, disrupting feeding and mucus production. After ingesting ferric phosphate slugs and snails stop 

feeding and death due to starvation will occur three to six days later. Ferric phosphate occurs naturally in 

soil but at considerably lower concentrations than that present in the formulated, baited product. 

Manufacture

Ferric phosphate occurs naturally in the soil; however, to achieve concentrations toxic to molluscs ferric 

phosphate must be supplemented through applications, most often with ferric phosphate formulated with 

a chelating agent. To produce ferric phosphate synthetically, an aqueous iron sulfate solution is mixed with 

an aqueous disodium phosphate solution in a stainless steel boiler. The mixture is heated to 50-70 °C in 

order to precipitate ferric phosphate. The precipitate is filtered from the solution, washed with distilled

NOSB October 2019 proposals and discussion documents Page 90 of 230
water, and dried with hot air. The baited pellets contain approximately 1% by mass of ferric phosphate with 

the remainder of the pellet comprised of a chelating agent and carbohydrate inerts. The EPA describes 

ferric phosphate as ubiquitous in nature. It is a solid. It is not volatile and does not readily dissolve in water, 

which minimizes its dispersal beyond where it is applied. 

International acceptance by other international certifying bodies

The European Union, the Canadian General Standards Board, The International Federation of Organic 

Agriculture Movement and the Japanese Organic Standard for Organic Plants all list ferric phosphate for use 

as a molluscicide in the protection of plants. 

Environmental/Health Issues

The EPA describes ferric phosphate as ubiquitous in nature. It is a solid. It is not volatile and does not 

readily dissolve in water, which minimizes its dispersal beyond where it is applied. Small concentrations of 

ferric phosphate are made available in soil solution when it is solubilized by commonly occurring soil 

microorganisms such as Penicillium radicum. 

Ferric phosphate by itself appears to be less toxic to a range of soil borne organisms (including slugs and 

snails) than when formulated with a chelating agent (EDTA or EDDS for example). The chelating agent 

enhances iron uptake by organisms in general. A number of published studies document that when 

formulated with a chelating agent, the efficacy for control of slugs and snails increases significantly. 

However, the increased efficacy also means its activity on non-target organisms like earthworms, domestic 

animals and humans also increases. The LD50 for ferric phosphate alone is greater than 10,000 mg kg while 

it drops to 80 mg kg when it is formulated with the chelating agents EDTA or EDDS (Ethylene diamine 

tetracetic acid – EDTA and Ethylene diamine disuccinic acid (EDDS). 

Discussion

The 2012 technical review addressed a series of concerns about the biological activity of ferric phosphate 

both in terms of its effectiveness in suppressing slugs and snails as well as its non-target effects on the 

ecology and abundance of soil dwelling organisms. Because the commercial formulations of ferric 

phosphate always included ferric phosphate itself and a chelating agent the NOSB was concerned about the 

effects of the formulated products used by farmers. Specifically, four questions regarding the efficacy of 

ferric phosphate alone and the synergizing effects of chelating agents (EDTA and EDDS) concluding without 

the chelating agent, ferric phosphate did not provide sufficient or consistent suppression of slugs and snails. 

In fact the efficacy was so low that it is hard to see why it would be used for slug and snail suppression 

without the chelating agent. The TR then asked, what risk does the use of ferric phosphate and its 

associated chelating agents pose to soil organisms and water quality. Here the existing data are scant. What 

has been researched (three studies published between 2006 and 2009) indicate a range of responses from 

non-significant to highly significant adverse effects of chelated ferric phosphate on a range of non-target 

organisms. A second technical review was sought and received to underpin this 2018 Sunset review. In that 

technical review, the Crops Subcommittee asked if additional research had been conducted addressing the 

following questions: 1) What new findings have been reported since 2009 that would inform our 

understanding of the influence of ferric phosphate alone and ferric phosphate in combination with 

commonly used chelating agents on the soil micro and macro fauna with particular attention to earthworm 

populations?; 2) To what extent is ferric phosphate used for slug and snail management in organic 

production?; 3) How are the products formulated that are detailed in (2) above?; 4) Since the July 26, 2012 

technical review, have additional studies been conducted documenting the effects of fieldworker exposure 

to ferric phosphate bait handling including inhalation of dust resulting from field applications. The same 

questions were posed to the public with a particular focus on the second question, how widely is ferric

phosphate used?

NOSB October 2019 proposals and discussion documents Page 91 of 230
From the 2018 technical review we learned that little additional research has been conducted since the 

2012 technical review quantifying the soil community response to ferric phosphate. The technical review 

did confirm that commercial formulations routinely include ferric phosphate and a chelating agent. We 

received considerable public comment on ferric phosphate learning that it is seen as an integral part of 

vegetable and fruit pest management and is widely used for slug and snail management in organic systems. 

We heard from some public comments that while a systems-approach is taken to address the slug and snail 

problem, attempts by organic farmers to increase reliance on cover-cropping and decreased tillage can lead 

to increased slug and snail abundance. The Subcommittee recognizes the efficacy of ferric phosphate is 

inextricably linked with the formulation; when formulated with a chelating agent, ferric phosphate 

effectively suppresses slugs and snails, unfortunately, the non-target effects on other soil organisms 

increase as well. 

Vote in Subcommittee: 

Motion to remove ferric phosphate from the National List at §205.605 based on the following criteria in the 

Organic Foods Production Act (OFPA) and/or 7 CFR 205.600(b): NA

Motion by: Dave Mortensen

Seconded by: Harriet Behar 

Yes: 0 No: 5 Abstain: 3 Absent: 0 Recuse: 0

Potassium bicarbonate

§205.601 Synthetic substances allowed for use in organic crop production.

Reference: 205.601(i) As plant disease control. (9) Potassium bicarbonate.

Technical Report: 1999 TAP; 2015 TR 

Petition(s): N/A

Past NOSB Actions: 10/1999 NOSB meeting minutes and vote; 11/2005 sunset recommendation; 10/2010 

sunset recommendation; 10/2015 sunset recommendation

Recent Regulatory Background: Sunset renewal notice published 06/06/12 (77 FR 33290); Renewed 

03/15/2017 (82 FR 14420)

Sunset Date: 3/15/2022 

Subcommittee Review:

Potassium bicarbonate is a plant disease control material. It is used by organic crop producers to control 

alternaria in cucurbits and cole crops; anthracnose in cucurbits, blueberries, grapes, spinach, and 

strawberries; black dot root rot and early blight in potatoes; sooty blotch and powdery mildew in apples; 

downy mildew in cucurbits, cole crops, grapes, and lettuce; gray mold (Botrytis cinerea) in beans, lettuce, 

and strawberries. These are just a few of the crops and specific diseases it helps to control. It is best suited 

for many of the powdery mildew diseases (TR lines 80-1) and early blight (1999 TAP). It has proven to be an 

important disease control aid in organic crop production.

Potassium bicarbonate is produced by carbonating potassium hydroxide to K2CO3, which is then carbonated 

to KHCO3. Carbonation is accomplished by injecting carbon dioxide gas into an aqueous solution of 

potassium hydroxide. (1999 TAP) 

The 1999 TAP review states that the decomposition products are potassium carbonate, water, and carbon 

dioxide, all of which readily dissipate in the environment. It found this material to be compatible with 

NOSB October 2019 proposals and discussion documents Page 92 of 230
organic crop production, safe, and more environmentally friendly than many of the synthetic alternatives. 

Potassium bicarbonate is a mild respiratory and eye irritant.

During the 2015 sunset review, a limited scope Technical Report (TR) was requested. The TR provided 

possible alternative materials or practices that might replace this material. Bacillus amyliquifaciens strain 

D747, Bacillus subtilis, Bacillus pumilis, gibberellic acid, and Streptomyces griseovirdis and lydicus,

Gliocladium catenulatum, and extracts of giant knotweed are all listed as natural alternatives for numerous 

plant diseases across many crops. Bordeaux mixture, kaolin, lime sulfur and sulfur, hydrogen dioxide, and 

neem extracts are offered as alternatives for both treatment and disease prevention across myriad crops 

and diseases, in addition to a variety of cultural and mechanical practices. Further clarification was sought 

in 2015 from stakeholders using this material to help explain under what conditions or scenarios the 

alternatives might be applied. Organic producers responded that while alternative materials and/or 

practices exist, potassium bicarbonate remains necessary for their particular crop production practices. 

Potassium bicarbonate is an important tool in powdery mildew resistance management. In addition to its 

efficacy on powdery mildew, stakeholders said its unique mode of action helps control other diseases under 

certain conditions or scenarios better than the alternative materials or practices. 

There was continued support for the continued listing of this material in 2015. One commenter was 

concerned that this material does not fit into any of the categories under §6517(c)(1)(B)(i) of OFPA. Others 

noted its extensive listing in Organic Systems Plans. Based on extensive public comment, the NOSB 

continued to find potassium bicarbonate compliant with OFPA criteria and did not recommend removal 

from the National List.

As part of the Spring 2019 public meeting, the Crops Subcommittee asked about efficacy of alternatives and 

the continued need for potassium bicarbonate. Written and oral testimony expressed continued support 

for this material, stating that it is used to control a number of diseases across a wide range of crops, 

including strawberries, cucurbits, tomatoes, and fruit trees. It is used in field, high tunnel, and greenhouse 

applications, and it is employed by some as part of a material rotation. One commenter expressed that it 

does not fit any OFPA categories of allowable synthetics.

Subcommittee vote

Motion to remove potassium bicarbonate from §205.601 (i) based on the following criteria in the Organic 

Foods Production Act (OFPA) and/or 7 CFR 205.600(b) if applicable: NA

Motion by: Emily Oakley

Seconded by: Dave Mortenson

Yes: 0 No: 7 Abstain: 0 Absent: 1 Recuse: 0 

Magnesium Sulfate

§205.601 Synthetic substances allowed for use in organic crop production.

Reference: 205.601(j) As a plant or soil amendment. (6) Magnesium sulfate—allowed with a documented 

soil deficiency.

Technical Report: 1995 TAP; 2011 TR

Petition(s): N/A

Past NOSB Actions: 04/1995 NOSB minutes and vote; 11/2005 sunset recommendation; 04/2010 sunset 

recommendation; 10/2015 sunset recommendation

NOSB October 2019 proposals and discussion documents Page 93 of 230
Recent Regulatory Background: Sunset renewal notice published 06/06/12 (77 FR 33290); Renewed 

03/15/2017 (82 FR 14420)

Sunset Date: 3/15/2022 

Subcommittee Review:

Magnesium sulfate is used to correct for magnesium soil deficiencies and helps to improve the uptake of 

nitrogen and phosphorus by crops, helps seeds germinate, increases chlorophyll production, aids in the 

production of flowering, and is vital in maintaining crop growth and yield.

Magnesium sulfate can be obtained from naturally occurring sources (kieserite or epsomite open-pit mines) 

or can be manufactured by a chemical process. Mineral forms of magnesium sulfate are dehydrated, 

purified, and reacted with sulfuric acid to create the synthetic version of magnesium sulfate. Historically, 

there have been no commercially available products containing mined, raw mineral magnesium sulfate in 

bulk quantities suitable for agriculture. For this reason, the production of synthetic magnesium sulfate has 

been necessary.

As stated in the 2011 Technical Report (TR) (lines 320-23): “If applied as a foliar feed in recommended 

doses (assuming also that a magnesium deficiency has been documented), magnesium sulfate would not be 

expected to produce toxic effects. However, if too much magnesium sulfate is added to the soil, or if the 

substance is added when a magnesium deficiency has not been determined, the uptake of other important 

nutrients will be affected.” The TR goes on to state that when used properly, it is unlikely to cause 

environmental or human health harm.

During the 2015 review, the Crops Subcommittee asked stakeholders if non-synthetic magnesium sulfate is 

available in the marketplace. Public comment indicated that the only form of non-synthetic magnesium 

sulfate that has been reviewed is potassium magnesium sulfate, or langbeinite; however, this material is 

not a reliable alternative because it is only available in limited quantities, and it is impossible to determine 

upon purchase whether langbeinite is synthetic or non-synthetic. There was substantial public comment in 

support of relisting magnesium sulfate. It is actively used by stakeholders and continues to be considered 

necessary to the production of fruit and vegetables. One commenter opposed the relisting, stating that 

nonsynthetic magnesium sulfate is available as langbeinite and dolomite; however, langbeinite is 

constrained by supply and classification issues. While dolomite can be used to treat a magnesium 

deficiency, the TR states that it is not as effective as magnesium sulfate and was not referenced by other 

commenters as a viable alternative. No significant new issues were raised, and the NOSB continued to find 

magnesium sulfate compliant with OFPA criteria and did not recommend removal from the National List.

As part of the Spring 2019 public meeting, the Crops Subcommittee asked if non-synthetic magnesium 

sulfate is available and about growers’ experiences using non-synthetic dolomite. Written and oral 

testimony expressed continued support for this material, stating that it is important in high tunnels and 

greenhouses as well as fruit tree production. Some growers commented that dolomite is not a suitable 

substitute in all cases as it cannot be used in high pH soils nor as a foliar application. It was also noted that 

there are few non-synthetic products on the market. Magnesium sulfate is also used in high pH soils when 

sulfur is needed but growers do not want to increase the pH. It is used alone and in blended products. 

Another commenter noted that use of magnesium sulfate should not take the place of soil building 

practices. 

NOSB October 2019 proposals and discussion documents Page 94 of 230
Subcommittee Vote: 

Motion to remove magnesium sulfate from §205.601 (j) based on the following criteria in the Organic 

Foods Production Act (OFPA) and/or 7 CFR 205.600(b) if applicable: NA

Motion by: Emily Oakley

Seconded by: Asa Bradman

Yes: 0 No: 7 Abstain: 0 Absent: 1 Recuse: 0 

Hydrogen chloride

§205.601 Synthetic substances allowed for use in organic crop production.

Reference: §205.601(n) Seed preparations. Hydrogen chloride (CAS # 7647-01-0)—for delinting cotton 

seed for planting.

Technical Report: 2003 TAP, 2014 Limited Scope TR

Petition(s): Hydrogen Chloride 10/30/02

Past NOSB Actions: 05/2004 NOSB recommendation for National List; 11/2009 sunset recommendation; 

4/2015 recommendation

Recent Regulatory Background: 

Added to National List 09/11/06 (71 FR 53299); Renewed 08/03/2011 (76 FR 46595) 

Renewed 09/12/16 (81 FR 8821)

Sunset Date: 9/12/2021

Subcommittee Review:

Use

Hydrogen chloride (2HCl) (CAS# 7647-01-0) forms a strong acid used for delinting cotton seed for planting. 

Hydrogen chloride is a liquid anhydrous hydrogen gas that is vaporized and then sprayed on cotton seeds 

after the ginning process. The gas mixes with the moisture in the seeds, resulting in acidic properties under 

which the lint on the seeds becomes weakened and is buffed off before planting. Because many fibers are 

attached to the seeds even after ginning, delinting improves handling (i.e., flowability ) for subsequent 

planting by mechanized equipment.

Manufacture

There are several methods used to produce hydrogen chloride. It can be synthesized directly or as 

a byproduct from manufacturing other chlorinated or fluorinated compounds.

International acceptance

Canadian General Standards Board Permitted Substances: Not listed. 

CODEX Alimentarius: Not Listed

European Economic Community (EEC) and India (NPOP): Hydrogen chloride not listed. Hydrochloric acid is 

listed for gelatin production and cheese processing (EEC)

Japan Agricultural Standard (JAS) for Organic Production: Not listed 

International Federation of Organic Agriculture Movements (IFOAM): Not 

listed.

Ancillary substances

None

NOSB October 2019 proposals and discussion documents Page 95 of 230
Impacts on health and the environment

Hydrogen chloride gas and subsequently produced hydrochloric acid are strongly corrosive materials 

and can cause skin burns, severe respiratory damage, circulatory system failure and death. Spills during 

manufacture or handling can injure workers or locally damage the environment.

Discussion

Hydrogen chloride for delinting cottonseed was recommended by the NOSB to be added to the National 

List in April 2004, and has been recommended each time it has subsequently been reviewed. However, 

hydrogen chloride, and the subsequently formed hydrochloric acid, are very corrosive materials and pose 

potential environmental and health threats if not handled properly. The 2014 limited scope TR identified 

several alternative, nonsynthetic delinting processes under development that were not commercially 

available at that time. The decision to relist was based on the lack of viable alternatives and the hope 

“that mechanical or other delinting processes are available to organic cotton growers by the next sunset 

review, so this very corrosive acid can be removed from the National List.” The 2014 limited TR included 

information (see Table 1 below) describing several alternatives to hydrogen chloride, and also referenced 

a mechanical cottonseed delinter under review by the USDA Agricultural Research Service. In follow-up 

to public comments from the Spring 2019 meeting, the Crops Subcommittee reached out to the Texas 

Organic Cotton Marketing Cooperative and Dr. Jane Dever, a professor and cotton breeder at Texas A&M 

for additional clarification on mechanical seed cleaning methods, obstacles to adopting non-chemical 

methods, and challenges addressing seed dormancy. 

Overall, comments and discussion reviewed for the Spring 2019 NOSB meeting and subsequent information 

NOSB October 2019 proposals and discussion documents Page 96 of 230
confirms that circumstances since 2014 are unchanged. Although progress has been made, viable 

alternatives to hydrogen chloride are not yet available. A key challenge is the small size of the U.S organic 

production market which does not economically incentivize companies to develop organic-specific 

technologies. Spring 2019 public comments were universally supportive of relisting hydrogen chloride as 

essential, and asserted that failure to do so would irreparably harm the U.S. organic cotton industry. 

Allowing the limited use of hydrogen chloride for seed preparation accrues economic and environmental 

benefits by supporting domestic organic cotton production and avoiding associated impacts of heavy 

pesticide use on conventional cotton. The need for additional specialized research to support alternatives

to hydrogen chloride, a caustic and potentially harmful material, were emphasized, and is supported by the 

Crops Subcommittee.

 

Subcommittee Vote:

Motion to remove hydrogen chloride for delinting cotton seed for planting based on the following criteria in 

the Organic Foods Production Act (OFPA) and/or §205.601(n) seed preparations if applicable: NA 

Motion by: Steve Ela 

Seconded by: Harriet Behar

Yes: 0 No: 7 Abstain: 0 Absent: 1 Recuse: 0 

Ash from manure burning

§205.602 Nonsynthetic substances prohibited for use in organic crop production.

Reference: 205.602(a) Ash from manure burning.

Technical Report: none

Petition(s): 2014

Past NOSB Actions: 04/1995 NOSB minutes and vote; 11/2005 sunset recommendation; 10/2010 sunset 

recommendation, 10/2015 sunset recommendation; 4/2016 NOSB formal recommendation

Recent Regulatory Background: Sunset renewal notice published 06/06/12 (77 FR 33290); Renewed 

03/15/2017 (82 FR 14420) 

Sunset Date: 3/15/2022 

Subcommittee Review:

Use: In some areas of nonorganic agriculture, the burning of manure to create an ash is used to lessen the 

volume of material (manure) transported to a field for fertilizer and to recover some of the nutrients in a 

more concentrated form (phosphorus, calcium, potassium and magnesium). The ash can then be used as a 

fertility input that is high in these nutrients. Large scale biochar manufacturing facilities claim that CAFOs 

can benefit from this manufacturing process, to lessen the impact of the volume of manure they need to 

dispose of from their facilities. This ash from manure has also been touted as a feed ingredient for 

livestock. The NOP organic standards do not allow re-feeding of manure to organic livestock. 

Manufacture: Manure can be thermally decomposed through combustion to produce this ash.

International: Canadian standards do not allow ash from manure burning to be used on organic crops. The 

EU does not allow manure from confined animal operations to be used on organic crops.

NOSB October 2019 proposals and discussion documents Page 97 of 230
Summary of Public Comment:

The vast majority of public comment addressing this material agreed with a continued listing as a 

prohibited material. However, one commenter discussed the benefits of controlled pyrolysis burning to 

create a manure-based biochar as being a good way to avoid the negative effects of nutrient leaching and 

other issues dealing with large volumes of raw manure. This commenter discussed the special property of 

heavy metal soil remediation in contaminated soils of manure-based biochars, over plant-based biochars. 

This was the only comment that answered the Subcommittee’s question in our first review: 

“Does ash from manure burning supply nutrients or other benefits that cannot be obtained from any other 

material?”

Discussion:

In April 2016, the NOSB responded to a petition to allow ash from manure burning with the following 

annotation: “except where the combustion reaction does not involve the use of synthetic additives and is 

controlled to separate and preserve nutrients”. The petitioner stated they source manure from 

Concentrated Animal Feeding Operations (CAFOs) and use a staged thermochemical reactor to extract 

minerals from their poultry manure source. The NOSB stated the following to support their 

recommendation to keep this material, as listed, as a prohibited nonsynthetic:

“Ash from manure burning was placed on §205.602 based on its incompatibility with organic production: 

“Burning these materials is not an appropriate method to recycle organic wastes and would not be 

considered a proper method in a manuring program because burning removes the carbon from these 

wastes and thereby destroys the value of the materials for restoring soil organic content. Burning as a 

disposal method of these materials would therefore not be consistent with section 2114(b)(1) of the OFPA (7 

U.S.C. 6513(b)(1)).” (Preamble to proposed rule, December 16, 1997. 62 FR 241: 65874)”

The USDA organic regulations require “soil-building” as a basic foundational principle, to improve soil tilth, 

water retention, nutrients and carbon sequestration. “§205.203 (c) The producer must manage plant and 

animal materials to maintain or improve soil organic matter content....” 

Soil microbiological life increases when provided with carbon-based sources containing a variety of 

nutrients, and extraction of nutrients while destroying others (such as nitrogen) does not meet either the 

letter, nor spirit of the USDA organic law or regulations.

The current crop subcommittee agrees with the previous NOSB recommendation, and prefers manure 

retain its full carbon and nutrient content, when used as a fertility input on organic land.

Subcommittee Vote:

Motion to remove ash from manure burning from §205.602 of the National List based on the following 

criteria in the Organic Foods Production Act (OFPA) and/or 7 CFR 205.600(b): NA

Motion by: Harriet Behar 

Seconded by: Jesse Buie

Yes: 0 No: 8 Abstain: 0 Absent: 0 Recuse: 0

NOSB October 2019 proposals and discussion documents Page 98 of 230
Sodium fluoaluminate (mined)

§205.602 Nonsynthetic substances prohibited for use in organic crop production.

Reference: 205.602(g) Sodium fluoaluminate (mined).

Technical Report: none

Petition(s): N/A

Past NOSB Actions: 05/1996 NOSB meeting minutes and vote; 11/2005 sunset recommendation; 10/2010 

sunset recommendation; 10/2015 sunset recommendation

Recent Regulatory Background: Sunset renewal notice published 06/06/12 (77 FR 33290); Renewed 

03/15/2017 (82 FR 14420)

Sunset Date: 3/15/2022 

Subcommittee Review:

Sodium fluoaluminate (Na3AlF6)—also known as “sodium fluoroaluminate,” “aluminum sodium fluoride,” 

“trisodium hexafluoroaluminate,” and “cryolite”—is a colorless to white halide mineral. It occurs in a large 

deposit at Ivigtut, Greenland, and in small amounts in Spain, Colorado, U.S., and elsewhere. It is used as a 

solvent for bauxite in the electrolytic production of aluminum and has various other metallurgical 

applications, and it is used in the glass and enamel industries, in bonded abrasives as a filler, and in the 

manufacture of insecticides (see www.britannica.com/science/cryolite for information on cryolite). Sodium 

fluoaluminate is also produced synthetically.

According to an EPA memorandum dated March 16, 2011, on the subject of “Cryolite. Human Health 

Assessment Scoping Document in Support of Registration Review” (link to document available via 

https://fluoridealert.org/researchers/pesticide/cryolite/): 

Cryolite [sodium aluminofluoride or sodium aluminum fluoride or sodium hexafluoroaluminate] is 

an insecticide used to control a variety of pests including various weevils, leaf rollers, various 

moth and worm species, and grape skeletonizers. Cryolite can be used on a wide array of 

agricultural crops including grapes (wine, table, raisin), cole crops, citrus, berries, tomatoes, 

cucumber, lettuce, and many types of ornamentals. Formulations include dusts, wettable 

powders, water dispersible granules, and baits/solids. Some formulations can contain as much as

96 percent active ingredient by weight. A recent evaluation of cryolite use indicates almost 2 

million pounds per year are applied on about 300,000 acres, most of which are on grapes (92% of 

total pounds applied and 96% of treated acres) (Prieto, 2010). Use in California accounts for the

vast majority of cryolite use (97%). In agriculture, groundboom, airblast, and aerial applications 

are typical but applications as a pure dust can also occur which may dictate other specialized 

forms of equipment being used. Applications to ornamentals may also be made using handheld 

equipment such as low and high pressure handgun sprayers and backpack sprayers. There are no 

cryolite containing products that appear to be marketed for sale to homeowners nor are there 

products which appear to be labeled for use by professionals in the residential marketplace (i.e., 

outdoors or indoors). Maximum application rates for most agricultural crops are in the 5 to 16 

pounds product per acre range while some uses, especially on ornamentals can be higher (i.e., up 

to 30 lb/A using a 96% formulation).

The potential toxicity of sodium fluoaluminate/cryolite is due to the release of fluoride into the 

environment due to the dissociation of cryolite into fluoride. The EPA memorandum cited above references 

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a number of animal toxicological studies on this substance; other studies related generally to fluoride 

toxicity are also referenced, since fluoride enters the environment in multiple ways—including fluoridated 

water—and therefore can have a cumulative adverse impact on health. 

There were no references to either sodium fluoaluminate or cryolite in the Canadian and European organic 

regulation websites. 

Public Comment from the Spring 2019 NOSB Meeting

There were only a few written comments received regarding sodium fluoaluminate prior to the Spring 2019 

NOSB meeting. All supported continued relisting of this substance as prohibited.

Conclusion

Given the toxicity associated with fluoride pollution in the environment and the multiple sources of such 

pollution, continued prohibition of this substance in organic production seems prudent. 

Additional information requested by Subcommittee

Are there any reasons why the long-standing prohibition on using sodium fluoaluminate in organic 

production should be reconsidered by the NOSB?

Subcommittee Vote:

Motion to remove sodium fluoaluminate (mined) from § 205.602 of the National List based on the following 

criteria in the Organic Foods Production Act (OFPA) and/or 7 CFR 205.600(b): NA

Motion by: Dan Seitz 

Seconded by: Jessie Buie

Yes: 0 No: 8 Abstain: 0 Absent: 0 Recuse: 0

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