National Organic Standards Board

Livestock Subcommittee

Petitioned Material Proposal

Glycolic Acid

February 20, 2018

Summary of Petition:

The NOSB received a petition to add glycolic acid for use as a component of pre- and post-milking teat dips to 

control mastitis at §205.603(a) Synthetic substances allowed for use in organic livestock production as 

disinfectants, sanitizer and medical treatment as applicable).

Summary of Review:

Specific Uses of the Substance:

Glycolic acid has been shown to be an effective post-milking teat disinfectant for dairy cows (Godden et 

al., 2016). Specifically, its petitioned use is as a component in a post-milking teat dip to aid in the 

prevention of bovine mastitis. Teat dips may contain emollients, excipients, and other allowed 

disinfectants. Because glycolic acid conditions the skin by exfoliating cracked skin layers, it removes 

potential hiding places for mastitis causing bacteria, e.g. Staphylococcus aureus.

In addition to its uses in skin care, glycolic acid is used in a broad range of applications. For example 

glycolic acid is used as a descaler for cutting through hard water salts, as a cleaning agent, as a liquid 

scour in laundry systems, as a copper and aluminum cleaner including boilers and heat exchangers, and 

as a dairy and CIP cleaner to dissolve casein as well as hard water deposits.

Glycolic acid is certified by the National Sanitation Foundation (NSF) for use in cleaning potable water 

wells. It is used widely to rehabilitate the flow efficiency of water wells by enabling water-soluble 

compounds (chelates) to be easily rinsed away with low corrosion to metal parts. Glycolic acid removes 

hard water scale (calcium, magnesium, manganese salts), various iron deposits and polysaccharide 

deposits. Glycolic acid biodegrades rapidly. It is a liquid with low toxicity, low odor, is non-flammable 

and has negligible fumes.

Approved Legal Uses of the Substance:

The first product containing glycolic acid as an active ingredient was registered by the U.S.

Environmental Protection Agency (EPA) in 2001 as a disinfecting cleaner and a disinfectant/sanitizer for 

non-food contacting, hard non-porous surfaces in residential and public access premises. Since then, 

additional products have been registered with the EPA. There are no tolerances, exemptions from 

tolerances, or tolerance petitions for this antimicrobial pesticide. Glycolic acid is approved by FDA as an 

indirect food additive for use in food packaging adhesives (21 CFR 175.105).

Glycolic acid is considered by the FDA to be a human cosmetic that is safe for use by consumers if the 

concentration is 10 percent or less, the pH is 3.5 or greater and the formulation protects the skin from 

increased sun sensitivity or the package directions instruct the consumer to use daily protection from 

the sun (FDA, 2015). Teat dips and udder washes classified as drugs, may currently be marketed without 

a New Animal Drug Application (NADA) approval. However, the FDA has developed non-binding 

guidelines for teat antiseptic product development. The guidelines were assembled to inform the drug 

industry of the types of data that will demonstrate that a teat antiseptic product: 1) is safe for the cow, 
2) is effective and 3) fulfills human food safety, manufacturing and environmental requirements. 

Products to be marketed must be manufactured according the Current Good Manufacturing Practice

(cGMP) regulations (21 CFR Part 211) for pharmaceutical dosage forms under the approved NADA 

process (FDA, 2016). 

The USDA does not regulate glycolic acid for application as a teat dip. However, the USDA regularly 

reports survey results for the dairy industry including statistics of use and recommendations for pre and 

post milking teat dips (USDA, 2016).

Action of the Substance: 

Glycolic acid is mildly bactericidal. However, its effect on the hyperkeratinization of skin is significant. 

Hyperkeratinization is a primary event in many skin disorders. It is caused by dying and dead adherent 

skin cells trapped near a hair follicle in the layers of tightly bound living cells called corneocytes. 

Normally, the dead cells are sloughed off by the follicles in a process called desquamation, but in the 

case of hyperkeratinization the dead cells are stuck beneath the tightly bound corneocytes. Dry skin, in 

wintertime is particularly vulnerable to reduced desquamation and hyperkeratinization. Glycolic acid has 

a therapeutic effect on hyperkeratinization, and the cohesiveness of corneocytes (Scott and Ruey, 1984). 

One theory for the mechanism of action of glycolic acid is that it reduces the calcium ion concentration 

in the epidermis and removes calcium ions from the cell adhesions by chelation. The cell adhesions are 

thereby disrupted, resulting in desquamation (Wand, 1999).

Glycolic acid reduces cohesiveness in the lower, newly forming layers of corneocytes potentially by 

inhibition of an enzyme. Glycolic acid does not cause disaggregation of corneocytes of the mature upper 

layer corneocytes, which would result in damage to the skin. Loosening the corneocytes in the lower 

layers improves desquamation. Glycolic acid promotes a thinner lower corneocyte layer, which not only 

improves the skin surface smoothness because the dead cells can migrate to the follicles, but also to 

improves the flexibility of the lower corneocyte layers (aka corneum stratum). A thin stratum corneum 

bends more readily without cracking or fissuring than a thick stratum corneum. Glycolic acid improves 

desquamation even if the skin is dry (Scott and Ruey, 1984). Bacteria take advantage of 

hyperkeratinization by entering the skin through cracks and fissures and colonizing the dead cells. The 

action of routine glycolic acid use is to remove both entry and colonization sites for colonizing bacteria 

that may lead to mastitis.

Manufacture:

Glycolic acid is a widely used industrial chemical with a large synthetic production footprint. It has 

commonly been produced by the Dupont process (hydratative carbonylation) from formaldehyde, 

carbon monoxide and water and in the presence of the catalyst sulfuric acid. The reaction is carried out 

at high pressure (300-700 bar) and temperature (200-250o

C).

HCHO + CO + H2O 

catalyst

 HOCH2COOH

Catalysts such as hydrogen fluoride, hydrogen fluoride/boron trifluoride and strongly acidic 

(perfluorinated) ion exchangers were subsequently introduced in the Chevron and Mitsubishi processes 

that are effective at low CO pressure (100 bar). Exxon developed another catalytic method to obtain 

70% glycolic acid at 150o

C on a strongly acidic ion exchanger made from perfluorosulfonic acid resin 

(Weisserme and Arpe, 2003).
Formaldehyde is a naturally occurring substance. It is the smallest aldehyde. Formaldehyde is produced 

industrially by the catalytic oxidation of methanol. The most common catalysts are silver metal or a 

mixture of metal oxides. In the commonly used Formox process, methanol and oxygen react at ca. 250–

400°C in presence of iron oxide in combination with molybdenum and/or vanadium to produce 

formaldehyde according to the chemical equation:

2 CH3OH + O2

catalyst

2 CH2O + 2 H2O

A silver-based catalytic process operates at a higher temperature, about 650 °C. Two chemical reactions 

on it simultaneously produce formaldehyde: that shown above and the dehydrogenation reaction:

CH3OH 

catalyst

CH2O + H2

In principle, formaldehyde could be generated by oxidation of methane, but this route is not industrially 

viable because the methanol is more easily oxidized than methane (Reuss et al., 2000).

Category 1: Classification 

1. Substance is for: X____ Livestock

2. For HANDLING and LIVESTOCK use:

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

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

Synthetic? 

All glycolic acid commercially available today is made by one of three processes: 

a) High temperature/High pressure continuous flow route practiced by The Chemours Company 

(formerly DuPont). This is the dominant form of glycolic acid production globally. Formaldehyde and 

carbon monoxide are the raw materials. 

b) Neutralization and reacidification of monochloroacetic acid (MCA). This is small batch 

conversions of MCA to glycolic acid with chlorinated organic and salt impurities. MCA is made from 

chlorine gas and acetic acid. Sodium hydroxide neutralizes the MCA and HCl reacidifies the product 

to glycolic acid. 

c) Enzymatic conversion of glycolonitrile to glycolic acid. Glycolonitrile is made from hydrogen 

cyanide and formaldehyde and has a similar impurity profile as the high temperature and pressure 

route of manufacture. 

All of these processes would be considered synthetic routes of manufacture. No “natural” source of 

glycolic acid is viable.

3. For LIVESTOCK: 

This product would be listed at §205.603 Livestock Production-Synthetic. Glycolic Acid is a 

synthetic substance in that it is manufactured using a chemical process. 
Category 2: Adverse Impacts 

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

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

Over the counter non-wipe post-milking dairy teat dips containing three percent glycolic acid (e.g. Ocean 

Blue Barrier®

) are also likely to contain 5% glycerol, 5% sorbitol, xanthan gum, povidone k30, c9-11 

Pareth-8, FD&C Blue No. 1, sodium hydroxide, water and sodium C14-16 olefin sulfonate. Package 

instructions do not suggest the use of one post-milking teat dip with another. The glycolic acid used for 

this formulation may be technical grade. Glycerin, an emollient, does not enhance the absorption of 

glycolic acid into the skin (Andersen, 1998). Sodium hydroxide is added to raise the pH of the teat dip. 

Low pH is a potential source of skin irritation when using glycolic acid to treat skin (FDA, 2015). Other 

ingredients used in teat dips include additional emollients, surfactants, colorants and plasticizers that 

permit adherence and identification of treated skin. Although there is general acceptance for the use of 

post milking teat dips, no advantage has been described for the use of multiple teat dip products in the 

same application (The National Mastitis Council, 2017).

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

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

[§6518(m)(2)]

In an early report, undiluted glycolic acid administered to rabbits was shown to cause acid-like burns to 

their skin and eyes (Carpenter and Smyth, 1946). Fifty and 70% Glycolic Acid applied to the backs of mini

pigs for 15 minutes caused epidermal necrosis, inflammatory infiltrate and for 70% Glycolic Acid dermal 

necrosis after one day (Andersen, 1998). Reproductive, gastrointestinal, developmental and renal 

toxicity in rats, cats and guinea pigs have also been demonstrated with oral administration of high doses 

(70-100%) of glycolic acid (NIOSH, 2017). Glycolic acid is known to cause enhanced sensitivity to UV 

light. Short-term application of 10% glycolic acid sensitizes the skin to UV light. However, this 

photosensitivity is reversed within a week of terminating treatments (Kaidbey et al., 2003). Glycolic acid 

is an important metabolite of ethylene glycol. Increased glycolic acid in the blood correlates directly with 

acute ethylene glycol toxicity and renal failure (Hewlett et al., 1986). Glycolic acid has been widely 

studied because it is used in health products and cosmetics. However, many of the conclusions of these 

studies have been equivocal or even contradictory. Varying or unreported conditions, parameters and 

criteria such as the concentration and grade of glycolic acid used and duration of exposure have made it 

difficult to assess and compare them. The primary areas of concern for glycolic acid however, are its 

dermal irritation potential and its potential to increase sensitivity to sunlight. Both of these factors result 

from glycolic acid’s ability to partially remove the stratum corneum layer of skin. Generally, for leave on 

products, glycolic acid concentrations not greater than 10% at pH no less than 3.0 will not produce 

unacceptable irritation. Glycolic acid does increase sensitivity to sunlight which should be considered in 

treatment (Andersen, 1998).

In six studies presented by the US Environmental Protection Agency, glycolic acid was noted to be 

slightly toxic to bluegill sunfish (Effective Concentration (EC)50=93 ppm), and practically non-toxic to 

bobwhite quail (Lethal Concentration (LC)50=>5000 ppm), Mallard duck (LC50=>5000 ppm), fathead 

minnow (LC50=164 ppm) and daphnia (EC50=141 ppm). In this same review, glycolic acid was noted to be 

only slightly toxic to mammals with an LC 50 of 1938 ppm (EPA, 2011). 

Glycolic acid as glycolate is an important intermediary molecule in plant photorespiration, but in excess 

it is toxic and can inhibit photosynthesis (Ogren, 2003; Dellero et al., 2016).The degree of inhibition and 
toxicity both depend on the particular species and variety of affected plant. In maize, for example, the 

accumulation of glycolate provokes the inhibition of ribulose bisphosphate carboxylase (RUBISCO) and

the subsequent decrease in CO2 assimilation (Gonzalez-Moro et al., 1997). Because it can inhibit 

photorespiration glycolic acid may be algistatic for some algal species , e.g. Selenastrum capricornutum, 

but since CO2 absorption pathways may vary between algal species, e.g. Chlorella spp., the appearance 

of toxicity is likely to be dependent upon glycolic acid concentration (EPA, 2011; Fogg and Nalewajko, 

1963; Raven et al., 2012). 

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

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

Most of the glycolic acid is manufactured at a chemical production plant in Belle, West Virginia. This 

chemical plant is located in the Kanawha Valley which is known for its many chemical manufacturing 

facilities. There have not been any major spills or accidents at this plant since 2010, when the release of 

phosgene gas into the atmosphere caused the death of an employee. The State of West Virginia 

provided the plant operator with a permit to operate and produce glycolic acid in 2015 (West Virginia 

Department of Environmental Protection, 2015). The permit expires in 2020 and permits respectively 

maxima of 1.9, 15.5, 15.2 8.14 and 5.85 tons/year of formaldehyde, methanol, formic acid, carbon 

monoxide and NOx to be released to the atmosphere from the plant’s thermal oxidizer.

The US EPA has not received any guideline environmental fate studies on glycolic acid, and has not 

required studies to be done. Since a toxicological concern has not been identified, the US EPA believes 

that, based on the currently registered use pattern of glycolic acid for household use as a 

disinfectant/sanitizer for hard non-porous surfaces in homes, guideline environmental fate or ecological 

effects studies are not necessary (EPA, 2011).

Various synthetic processes are available for preparing glycolic acid. Contaminants potentially found in 

downstream products are formaldehyde and monochloroacetic acid which are the starting materials. 

Residual reagents include sodium chloride, formic acid, methoxyacetic acid which are byproducts from 

the synthesis process. These impurities must be controlled for safety and the physical and chemical 

characteristics of the product (Liedtka, 2016). Glycolic Acid is available as a technical grade 70% solution 

and as higher purity grade solutions of 70% (Glypure 70) and 99% (Glypure 99) (Chemours, 2015). 

Because of the amount of impurities, technical-grade Glycolic Acid is not used in personal care 

applications (Andersen, 1998, Table 2). The US FDA found no concerns about the physical and chemical 

characterization when potential impurities, such as formaldehyde are controlled at acceptable levels. 

Glycolic acid is a well-characterized small molecule that is likely to be stable under ordinary storage 

conditions (Liedtka, 2016).

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

§6518(m)(4)].

Labels for products containing 3% glycolic acid for use as a pre- and post-milking teat dip indicate only 

that the substance can cause eye irritation (MSDS, OceanBlu Barrier, deLaval). Glycolic acid at different 

concentrations is used for a number of human medical procedures as a keratolytic agent. Glycolic acid at 

57-70% is corrosive to the skin and eyes. Ingestion of substantial amounts at this concentration may 

result in kidney failure (PubChem, 2017). Glycolic acid in cosmetic products used by the general public 

may cause skin and eye irritation when present at high concentrations and low pH values. In addition, 

manufacturers, importers and suppliers of consumer products should inform consumers that the use of 
skin exfoliant cosmetic products may result in an enhanced sensitivity to sunburn, and that use of 

sunscreen protection is advised (NICNAS, 2000).

Occupational exposure to glycolic acid may occur through inhalation and dermal contact with this 

compound at workplaces where glycolic acid is produced or used. Monitoring and use data indicate that 

the general population may be exposed to glycolic acid via inhalation of ambient air, ingestion of food 

and dermal contact with consumer products containing glycolic acid (NCBI, 2017).

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

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

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

The chemomechanic action of alphahydroxy acids (AHAs) in exfoliation is to reduce calcium ion 

concentration in the epidermis and remove calcium ions from the cell adhesions by chelation causing 

disruption in cell adhesions and desquamation. Glycolic acid can also suppress melanin formation by 

inhibition of tyrosinase activity. Intraperitoneal administration of 1000 mg/kg glycolic acid inhibits 

oxygen consumption and glucose metabolism in rat liver and myocardium in vivo, but does not affect 

brain oxygen consumption. Glycolic acid in high concentrations (70% solution and pure) causes local 

effects typical of a strong acid, such as dermal and eye irritation. In a 3-week dermal toxicity study in 

hairless guinea pigs, erythema and/or flaking of the skin were noted at 5% and 10% concentrations of 

glycolic acid. Glycolic acid induced calculi formation in rats in a 4- to 12-week repeat dose oral toxicity 

which also disclosed increased renal oxalate and nephrotoxic effects have been observed. In a 2 week 

study in rats, respiratory tract irritation, hepatocellular degeneration and thymus atrophy were 

observed. Glycolic acid was negative for mutagenicity in the Ames test and the mouse lymphoma assay 

and not considered genotoxic. Glycolic acid was negative for clastogenicity in an in vitro chromosome 

aberration assay and an in vivo micronucleus assay in mice. 

Carcinogenicity from glycolic acid exposure has not been demonstrated. Oral (gavage) doses of glycolic 

acid up to 600 mg/kg/day were administered to female rats during gestation days 7-21 – Maternal 

toxicity was seen at doses ≥ 300 mg/kg/day – Developmental toxicity was also noted at doses ≥ 300 

mg/kg/day, including fetal weight reduction and increases in skeletal malformation (FDA, 2005). Glycolic 

acid post milking treatment can affect keratin dynamics (The National Mastitis Council, 2017). Glycolic 

acid is non-toxic in dogs up to 100 milligrams/kilogram, but nephrotoxic effects result from doses of 250 

mg/kg, and fatality occurs if greater than 500 mg/kg is ingested. Glycolic acid is also nephrotoxic to cats 

(Krop and Gold, 1944).

Glycolic acid is found in the fruit, leaf, stem and root portions of all plants. Glycolic acid is found 

naturally in extractable amounts in sugar cane and sugar beets (Thangaevelu, 2010; Stark et al., 1950). It 

is also excreted naturally by several algal species (Tolbert and Zill, 1956). Commonly consumed fruits 

and vegetables are reported to contain from 0.45-7.4 milligrams glycolic acid per 100 grams fresh wet 

weight. Tea, coffee, fruit juice and other beverages derived from plant sources may contain 5-7 mg 

glycolic acid per 100 mL. Foods of animal origin are generally low in glycolic acid, with milk and beef 

reported to contain 0.06-0.12 mg per 100 g (NICNAS, 2000). It is readily biodegradable in soil and water. 

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

Glycolic acid is found in ruminant blood. Studies have shown that it is incorporated into 

casein, fat and lactose of milk (Peters et al., 1971). 
There have not been any reports of adverse environmental events related to glycolic acid release. 

Approximately 0.15 ml of glycolic acid (3%) is used per udder quarter in a post milking test dip (Matti 

and Tinnis, 2015). Glycolic acid at a concentration of 70% is approved for use as an acid non-food 

cleaning agent for removal of rust, corrosion, scale or other deposits that are not readily removed by 

alkaline cleaners in dairies.

Glycolic acid is a significant industrial chemical (EPA, 2011). If released to air at an extrapolated vapor 

pressure of 0.02 mm Hg at 25 o C, glycolic acid will exist solely as a vapor. Vapor-phase glycolic acid will 

be degraded in the atmosphere by reaction with photochemically-produced hydroxyl radicals; the halflife for this reaction in air is estimated to be 3.4 days. Glycolic acid does not contain chromophores that 

absorb at wavelengths >290 nm and, therefore, is not expected to be susceptible to direct photolysis by 

sunlight. If released into soil, glycolic acid is expected to have very high mobility based upon an 

estimated Koc of 0.14. Koc is a measure of the tendency of a chemical to bind to soils, corrected for soil 

organic carbon content. The pKa of glycolic acid is 3.6, indicating that this compound will exist almost 

entirely in anion form in the environment and anions generally do not adsorb more strongly to soils 

containing organic carbon and clay than their neutral counterparts. Volatilization of glycolic acid from 

moist soil surfaces is not expected to be an important fate process because the compound exists as an 

anion and ions do not volatilize. Glycolic acid is not expected to volatilize from dry soil surfaces based 

upon its vapor pressure. Tests for inherent biodegradability showed 86% of the theoretical BOD was 

reached in 2 weeks. This indicates that biodegradation is an important environmental fate process in soil 

and water. If released into water, glycolic acid is not expected to adsorb to suspended solids and 

sediment based upon the estimated low Koc. A pKa of 3.6 indicates glycolic acid will exist almost entirely 

in the anion form at pH values of 5 to 9 and, therefore, volatilization from water surfaces is not expected 

to be an important fate process. An estimated BCF of 3 suggests the potential for bioconcentration in 

aquatic organisms is low. Hydrolysis is not expected to be an important environmental fate process 

since this compound lacks functional groups that hydrolyze under environmental conditions. 

Category 3: Alternatives/Compatibility

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

The pathogens that cause mastitis inhabit many locations throughout the dairy cow environment and 

infect multiple tissues in the udder. As a result, effective prevention and treatments for mastitis in the 

organic dairy a can range from surface sanitation to parenteral administration of homeopathic 

medicines, but each alone may not be 100% effective. Thus, there are many possible substances that 

may serve in place of glycolic acid. Glycolic acid represents a unique approach to bovine teat health, 

inasmuch as the net effect is to prevent hyperkeratosis, although there is additionally some 

microbiocidal activity associated with its application. 

Vitamin A is similar to glycolic acid in its action, however; the subset of skin cells that are affected are 

not the same (Scott and Ruey, 1984). Thus, vitamins and minerals to supplement nutrition such as 

vitamin, selenium, copper, zinc, vitamin A and β-carotene are important to both bolster both cellular 

and humoral immune response and to maintain skin and udder health (Heinrichs et al., 2009). Low blood 

plasma concentrations of vitamin A and β-carotene are directly associated with the severity of mastitis 

in cows (Chew et al., 1982).

Homeopathic pharmacies can provide pre-prepared remedies for mastitis in dairy cows. Udder liniments 

containing mint or anti-inflammatory agents are often used as support therapy with homeopathy (Hovi 

and Roderick, 1998). More examples include Belladonna for acute postpartum mastitis; Aconitum for 
routine treatment for all acute cases, particularly those that develop rapidly after exposure to cold dry 

wind; Apis Mellifica is indicated for first calving, heifers with edema of and around the udder; Bryonia 

Alba is indicated for swollen and very hard udders; Arnica Montana for mastitis resulting from udder 

injuries; Belia Perennis for deeper injuries (e.g., neglected milkers); Phytolacca for clinical and chronic 

cases with sour, coagulated milk, small clots at mid-lactation; Urtica Ulens for clinical cases where 

edema forms plaques sometimes up to perineum; mixtures of Sulphur, Silica and Carbo Vegetabilis for 

clinical and subclinical cases; Hepar Sulphuris to aid suppuration and cleaning of udder in summer 

mastitis cases; Silicea for summer mastitis cases with purulent abscess and Ipeca for treating internal 

bleeding that produces pink or bloody milk (MacLeod, 1981). Homeopathic remedies used to treat 

mastitis also include: Belladonna, Lachesis, Vipera Reddi, Conium maculatum + Plumbum iodanum, 

Phytolacca, Bryon and Silicea (Quiquandon, 1982). Homeopathic remedies are not regulated for efficacy 

and quality as are veterinary drugs, therapies and medications. Furthermore, some research indicates 

that homeopathic approaches are not effective therapies for bovine mastitis (Ebert et al., 2017).

Currently only iodine (§205.603(a)(13) and §205.603(b)(3)), chlorhexidine §205.603(a)(6), glycerin 

§205.603(a)(11), and hydrogen peroxide §205.603(a)(12), are allowed to be used in organic dairy 

production for mastitis prevention and therapy. Teat dips containing the disinfectants iodine and 

chlorhexidine are effective in reducing intra-mammary infections (Enger et al., 2016). Iodine is effective 

as a pre- and post-milking teat dip or spray, however, small increases in milk iodide concentration can 

be expected with its use. Where sprays usually produce a larger increase than dip cup preparations 

(French et al., 2016). Chlorine materials (§205.603(a)(7)) and phosphoric acid (§205.603(a)(19)) are 

allowed for sanitizing equipment and facilities. Vaccines, anti-inflammatory drugs (e.g., aspirin and 

flunixin), electrolytes, and furosemide (with double the milk withholding period) can also be used for the 

treatment of clinical mastitis (Ruegg, 2014).

Post-milking teat disinfectants need to be persistent and effective in killing bacteria. They must also 

leave teats in good condition. Preservation of healthy teat skin is essential for maintaining its natural 

defense against infection because sore, dry, cracked teats may harbor mastitis-causing pathogens 

(Hogan et al., 1990; National Mastitis Council, 2017). Barrier type teat disinfectants have been 

developed to extend the germicidal properties of the disinfectant after the cow leaves the milking 

parlor. These products contain components that can provide a protective film and seal the teat from 

mastitis-causing bacteria (Lago et al., 2016). Glycerin is a humectant that is allowed for use as a skin 

conditioner in teat dips. Aloe is a naturally derived products with skin healing properties that may also 

be included in teat dips (Fox et al., 2006).

Teat irritation can be caused by interaction between teat dip and management or environmental factors 

in a herd. Teat dips may promote chapping during extremely cold weather especially with windy 

conditions. Emollients are incorporated such as glycerin or lanolin to minimize irritation and condition 

skin, however, the germicidal effectiveness of the teat dip may be diminished with too much emollient 

(Pankey, 1984). Emollients and humectants do not affect bacterial colonization of the skin (Rasmussen 

and Larsen, 1998).

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

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

agriculture? [§6518(m)(7)]

Yes, but it is unclear if this substance is needed in organic agriculture as alternatives exist. Therefore, 

the Subcommittee would like to pose the following questions:
1. Are there alternatives available for pre-and post-milking teat dips?

2. Is this product used in rotation with currently allowed pre-and post-milking teat dips?

3. Do alternatives work to control mastitis?

Classification Motion: 

Motion to classify glycolic acid as synthetic

Motion by: Ashley Swaffar

Seconded by: Harriet Behar

Yes: 5 No: 0 Abstain: 0 Absent: 1 Recuse: 0

National List Motion: 

Motion to add glycolic acid as petitioned at 205.601

Motion by: Ashley Swaffar

Seconded by: Jesse Buie

Yes: 3 No: 2 Abstain: 0 Absent: 1 Recuse: 0

Approved by Ashley Swaffar, Livestock Subcommittee Chair, to transmit to NOSB February 23, 2018