United States Department of Agriculture Agricultural Marketing Service | National Organic Program Document Cover Sheet https://www.ams.usda.gov/rules-regulations/organic/national-list/petitioned

Document Type:

☐ National List Petition or Petition Update

A petition is a request to amend the USDA National Organic Program’s National List of Allowed and Prohibited Substances (National List).

Any person may submit a petition to have a substance evaluated by the National Organic Standards Board (7 CFR 205.607(a)).

Guidelines for submitting a petition are available in the NOP Handbook as NOP 3011, National List Petition Guidelines.

Petitions are posted for the public on the NOP website for Petitioned Substances.

☒ Technical Report

A technical report is developed in response to a petition to amend the National List. Reports are also developed to assist in the review of substances that are already on the National List.

Technical reports are completed by third-party contractors and are available to the public on the NOP website for Petitioned Substances.

Contractor names and dates completed are available in the report.

Calcium Acetate Crops 1 2 Identification of Petitioned Substance 3 4 Chemical Names: 24 Full Measure CalTM 30 5 Calcium Acetate 25 ReflectionsTM 6 Calcium Diacetate 26 7 Acetic Acid, Calcium Salt CAS Numbers: 8 Calcium (II) Acetate 62-54-4 (Calcium Acetate) 9 Calcium Ethanoate 5743-26-0 (Calcium Acetate Monohydrate) 10 Calcium Acetate Monohydrate 114460-21-8 (Calcium Acetate Hydrate) 11 Calcium Diacetate Hydrate 12 Calcium Diacetate Monohydrate Other Codes: 13 Acetic Acid, Calcium Salt, Monohydrate EC No. 200-540-9 (Calcium Acetate) 14 EC No. 611-528-1 (Calcium Acetate 15 Other Names: Monohydrate) 16 Lime Acetate FEMA No. 2228 17 Acetate of Lime ICSC No. 1092 18 Lime Pyrolignite RTECS No. AF7525000 19 Vinegar Salts UNII No. Y882YXF34X (Calcium Acetate) 20 UNII No. 7ZA48GIM5H (Calcium Acetate 21 Trade Names: Monohydrate) 22 PhosLo® 23 ProcalAmine® 27 Summary of Petitioned Use 28 29 The petitioners are requesting to add calcium acetate, the salt resulting from the neutralization of acetic acid with 30 calcium hydroxide or calcium carbonate, to Title 7 of the Code of Federal Regulations section 205.601 (7 CFR 31 205.601) as a “synthetic substance allowed for use in organic crop production.” 32 33 Calcium acetate acts as a soil amendment, plant micronutrient, pH adjuster, and preventative of sunscald. 34 Calcium acetate provides a water-soluble and bioavailable source of the essential micronutrient calcium for plant 35 absorption. When used as petitioned, calcium acetate is applied as an aqueous mixture with calcium carbonate 36 (limestone) and a surfactant. The combination of calcium acetate and calcium carbonate serves to increase soil 37 alkalinity (pH adjustment). The petitioned mixture also prevents sunscald by blocking direct sun exposure and 38 lowering soil temperature. 39 40 Characterization of Petitioned Substance 41 42 Composition of the Substance: 43 Calcium acetate is an organic salt that is found as a component in the metabolic pathways of a variety of 44 animals, including humans (EFSA 2009, EFSA 2012). Commercial forms of calcium acetate are 45 manufactured by the neutralization of acetic acid with either calcium carbonate or calcium hydroxide salts 46 (EPA 2010a, Hawley 2016). The petitioned substance is hygroscopic (absorbs water) making most 47 commercial sources calcium acetate hydrates (including water molecules), although anhydrous calcium 48 acetate (calcium acetate without water incorporation) is also available (Capot 2013, ILO 2002, Merck 1996, 49 EU 2012, Perry 2011, PubChem 6116, PubChem 82163, Sigma-Aldrich 2016, Sigma-Aldrich 2018). 50 51 Source or Origin of the Substance: 52 Calcium acetate is a naturally occurring substance, which is produced and broken down in the metabolic 53 cycles of a range of humans and animals; however, it is most commonly manufactured by the

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54 neutralization of acetic acid with calcium carbonate (limestone, Equation 1) or calcium hydroxide 55 (hydrated lime, Equation 2) (EFSA 2009, EFSA 2012, EPA 2010a, Hawley 2016). 56 O O O 2+ + H2O + CO2 + 2+ CO 2- Ca Ca 3 - - OH O O acetic acid calcium carbonate calcium acetate water carbon dioxide

57 Equation 1 O O O + (2) H2O + - Ca OH- Ca2+ OH 2+ - - OH O O acetic acid calcium hydroxide calcium acetate water

58 Equation 2 59 60 Properties of the Substance: 61 Calcium acetate is commercially available as a solid in >98% purity in anhydrous, monohydrate, and 62 hydrate forms. However, the anhydrous form (calcium acetate) is hygroscopic (absorbs water/moisture), 63 and since the substance is used in an aqueous mixture, the monohydrate or hydrate forms are more likely 64 to be used for the petitioned application (Merck 1996). The properties of the commercially-available forms 65 of calcium acetate are summarized in Table 1. 66 67 Table 1: Properties of Calcium Acetate 68 Compound Calcium Acetate Calcium Acetate Calcium Acetate Hydrate Monohydrate CAS No. 62-54-4 114460-21-8 5743-26-0 Molecular Weight 158.17 g/mol 158.17 g/mol 176.18 g/mol Appearance Colorless-white Solid Brown, gray, or white crystalline solid solid powder General Properties Very Hygroscopic, Hygroscopic, Hygroscopic, Slight odor of acetic Slight odor of acetic Slight odor of acetic acid acid acid Solubility Soluble in water, N/A Soluble in water, slightly soluble in slightly soluble in alcohols alcohols Melting Point 160 oC (decomposes) N/A N/A (decomposes) Density 1.5 g/cm3 N/A N/A 69 Sources: (Capot 2013, ILO 2002, Merck 1996, EU 2012, Perry 2011, PubChem 6116, PubChem 82163, Sigma- 70 Aldrich 2016, Sigma-Aldrich 2018) 71 72 Specific Uses of the Substance: 73 Calcium acetate is petitioned for use as a soil amendment. Calcium acetate is a water-soluble salt for use as 74 a bioavailable source of the essential micronutrient calcium (Ca2+) (Merck 1996, EU 2012, Peacock 2005, 75 Perry 2011, PubChem 6116, PubChem 82163, Sigma-Aldrich 2016, Sigma-Aldrich 2018). Calcium is an 76 important micronutrient for plant growth, providing important structural rigidity to cell walls and 77 membranes, protection from microbial diseases, and proper regulation of cellular transport and enzyme 78 function (Bennett 1993, Frizzel and Loosemore 2010, Helper 2005, Hirschi 2004, Marschner 1995). The 79 petitioned substance improves the delivery of calcium compared to other calcium treatments (e.g., lime) September 14, 2018 Page 2 of 15 Technical Evaluation Report Calcium Acetate Crops

80 due to its increased water solubility (Frizzel and Loosemore 2010, Peacock 2005). When the petitioned 81 substance is combined with insoluble calcium carbonate, the mixture acts to further improve the 82 fertilization method by delivering immediate calcium nutrition with calcium acetate and prolonged 83 nutrition from calcium carbonate (Frizzel and Loosemore 2010). Furthermore, calcium acetate has been 84 reported to increase plant absorption of calcium ions (Ca2+) compared to salts with other organic and 85 inorganic anions (e.g., lactate, citrate, oxalate, chloride, nitrate) (Borchert 1986). 86 87 Calcium acetate is also petitioned for adjustment of soil pH. Acetate is the conjugate base of the weak 88 organic acid acetic acid (Equations 1 and 2); therefore, the application of acetate will act to establish a buffer 89 and increase the alkalinity (and raise the pH) of the soil by reacting with both strong and weak acids. 90 However, the applied mixture will consist of ~5% calcium acetate, with the remaining calcium content in 91 the form of calcium carbonate. Calcium carbonate is naturally produced and exists in many forms, 92 including mineral deposits (e.g., limestone, calcite, and marble) and as a structural component of bones and 93 shells (e.g., eggshells, seashells) (USDA 2018, USGS 2008). Calcium carbonate will also react as a base, 94 neutralizing strong and weak acids and resulting in the formation of a new calcium salt, water, and carbon 95 dioxide (CO2) gas (as seen with the neutralization of acetic acid in Equation 1) (Al Omari et al. 2016, EFSA 96 2011, Holman and Stone 2001, Oates 1998). Although calcium carbonate has very low water solubility, the 97 ionic compound is broken up by acids, greatly increasing the solubility of the calcium cation and providing 98 access to the basic properties of the carbonate anion (EFSA 2011, Oates 1998). 99 100 Calcium acetate is petitioned for use as an aqueous mixture that also includes calcium carbonate, xanthan 101 gum (as a stabilizer), and in some cases humic acid. This mixture of substances is not completely soluble, 102 and its suspended solid particles shield plants from ultraviolet radiation and regulate plant temperature. 103 Sunscald occurs when exposure to sunlight overheats crops and results in scar formation (Piskolczi et al. 104 2004). These scars are visible on the surface of the crop, and persist into sub-surface layers, affecting the 105 color, taste, and properties of the crop before and after harvest (Lurie and Watkins 2012, Piskolczi et al. 106 2004, Schrader et al. 2001). The aqueous mixture — which includes the petitioned calcium acetate, calcium 107 carbonate, and the surfactant xanthan gum — is petitioned for protection of crops from sunscald. This 108 protective property is due to the opaque nature of the mixture, largely due to the presence of insoluble 109 calcium carbonate in the final formulation, which protects plants from ultraviolet radiation while 110 simultaneously regulating plant temperature (Frizzel and Loosemore 2010). 111 112 Calcium acetate has been used in animal feeds for nutritional purposes as well as a preservative and 113 veterinary medicine due to its mild anti-microbial effects (EFSA 2012). Calcium acetate has also been 114 established for a range of other non-agricultural applications, including cosmetics and various household 115 products (EFSA 2012). 116 117 Calcium acetate has been approved by the United States Food and Drug Administration (FDA) as an “inert 118 ingredient permitted in minimum risk pesticide products,” at 40 CFR 152.25. Calcium acetate is employed 119 in a contained trap and is used to attract yellow jackets through scent recognition, after which the yellow 120 jackets are trapped in the container (EPA 2010a, EPA 2010b). 121 122 Approved Legal Uses of the Substance: 123 Calcium acetate has been given GRAS (Generally Recognized as Safe) status by the FDA as a “sequestrant,” 124 at 21 CFR 582.6185 and a “direct food substance,” at §184.1185. The FDA has approved calcium acetate as a 125 “firming agent, pH control, processing aid, sequestrant, stabilizer, thickener, and texturizer,” at §184.1185. 126 This section further specifies that calcium acetate is approved as an “ingredient used in food with a 127 maximum level as served of 0.2 percent for baked goods; 0.02 percent for cheese; 0.2 percent for gelatins, 128 puddings, and fillings; 0.15 percent for sweet sauces, toppings, and syrups; and 0.0001 percent for all other 129 food categories.” 130 131 The FDA has approved calcium acetate for use in food processing as a “substance classified as a stabilizer 132 when migrating from food-packaging material,” at 21 CFR 181.29. Calcium acetate has also been classified 133 by the FDA as a “miscellaneous material” for use as a “resinous and polymeric coating [that] may be safely

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134 used as the food-contact surface of articles intended for use in producing, manufacturing, packing, 135 processing, preparing, treating, packaging, transporting, or holding food,” at §175.300. 136 137 The FDA has approved calcium acetate for use in “drug products containing certain active ingredients 138 offered over-the-counter (OTC)” for astringent drug products, “except calcium acetate monohydrate when 139 combined with aluminum sulfate tetradecahydrate to provide an aluminum acetate solution,” at 21 CFR 140 310.545. Furthermore, the FDA has approved calcium acetate as a precursor to aluminum acetate in 141 “astringent products,” at §347.52(a). Calcium acetate is also approved for relieving minor skin irritations 142 such as those caused by poison ivy, oak, or sumac as well as rashes from a variety of soaps and detergents. 143 It is approved “for use as a soak,” at §347.52(b) and (c), respectively. 144 145 The United States Environmental Protection Agency (EPA) has granted calcium acetate an “exemption for 146 pesticides of a character not requiring FIFRA [(the Federal Insecticide, Fungicide, and Rodenticide Act)] 147 regulation,” and has classified the substance as an “inert ingredient permitted in minimum risk pesticide 148 products,” at 40 CFR 152.25. Calcium acetate has been registered as a pesticide for yellowjackets with the 149 EPA in 2010 (EPA 2010a, EPA 2010b). 150 151 Action of the Substance: 152 Calcium acetate works as a soil amendment in two ways, one of which is for micronutrient delivery. 153 Calcium is an important structural component in plants, providing rigidity to the cell wall and stabilizing 154 lipids within cell membranes (Bennett 1993, Frizzel and Loosemore 2010, Helper 2005, Hirschi 2004, 155 Marschner 1995). Calcium is also important for the regulation of many cellular processes, ranging from 156 transport across cellular membranes to enzymatic function (Bennett 1993, Helper 2005, Hirschi 2004, 157 Marschner 1995). The application of calcium acetate as a micronutrient fertilizer provides superior 158 absorption compared to other fertilization programs (e.g., lime). This increased absorption is due to the 159 increased water solubility, and therefore bioavailability, of the calcium ions (Borchert 1986, Frizzel and 160 Loosemore 2010, Peacock 2005). This increase in bioavailability is more pronounced in alkaline (high pH) 161 soils, where micronutrients (i.e., calcium) are present as insoluble carbonate and hydroxide salts (Frizzel 162 and Loosemore 2010, Peacock 2005). Borchert (1986)reported that calcium absorption from calcium acetate 163 was superior to other soluble organic and inorganic calcium salts and proposed the increased calcium 164 uptake because of the acetate anion. When used as a soil amendment, humic acid may be added to the 165 final aqueous mixture for additional nutrition. Humic acids have been reported to act as chelating agents, 166 which increase the water solubility and bioavailability of micronutrients following their coordination 167 (Merck 2006, USDA 2012). 168 169 The petitioned substance also acts as a soil pH adjuster. When used as petitioned, the substance is applied 170 as an aqueous mixture of calcium acetate, calcium carbonate, and a surfactant (xanthan gum). Both calcium 171 sources (acetate and carbonate) are conjugate bases of weak acids (acetic acid and bicarbonate, 172 respectively). As such, they can react with and neutralize weak and strong acids. Both calcium salts enable 173 the creation of a buffering system that raises the pH of the soil, while also providing an increased buffering 174 capacity (alkalinity) to the soil (Frizzel and Loosemore 2010, Peacock 2005). Calcium carbonate has long 175 been applied as a soil amendment to raise pH and is present as a buffering agent in a wide range of 176 environments due to its prevalence in the earth’s crust (Al Omari et al. 2016, EFSA 2011, USGS 2008). 177 178 When used for sunscald prevention, calcium acetate operates under a different mode of action. Sunscald 179 results from crops overheating, producing discolorations and affecting taste and other post-harvest 180 properties (e.g., storage and marketability) (Lurie and Watkins 2012, Piskolczi et al. 2004). When used as 181 petitioned, the aqueous mixture including calcium acetate prevents sunscald due to the suspension of solid 182 particles in the mixture that yields an opaque liquid when applied (Frizzel and Loosemore 2010). The 183 nature of the mixture physically protects crops from ultraviolet radiation and regulates plant temperature 184 to prevent the overheating that results in sunscald formation. 185 186 Combinations of the Substance: 187 When used as petitioned, calcium acetate is applied as an aqueous mixture that also includes calcium 188 carbonate, xanthan gum as a surfactant, and in some cases, humic acid for additional nutrition. Thirty

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189 percent (30%) of the final mixture is made from calcium acetate and carbonate salts, with calcium acetate 190 accounting for ~5% and calcium carbonate accounting for the other ~25% (USDA 2017). 191 192 Calcium carbonate contrasts with calcium acetate by being insoluble in water and is present in the 193 petitioned substance as suspended solid particles (Millipore-Sigma 2015, PubChem 10112). Calcium 194 carbonate aids in all three applications of the petitioned substance. Calcium carbonate is a source of 195 calcium ions (Ca2+), which although initially insoluble, become accessible upon reaction with an acid 196 (Equation 1) (EFSA 2011, Oates 1998). Calcium carbonate also acts to raise soil pH by reacting with acids in 197 the environment (Equation 1). The application of calcium carbonate results in increased soil alkalinity, 198 enhancing the buffering capacity of the ecosystem (USGS 2008). The insoluble nature of calcium carbonate 199 in aqueous mixtures results in a slow release soil amendment, both in terms of nutrition and pH 200 adjustment, complementing the immediately available calcium acetate (Frizzel and Loosemore 2010). 201 Moreover, the insolubility of calcium carbonate results in the opaque character of the final mixture, 202 allowing for sunscald prevention (Frizzel and Loosemore 2010, USDA 2017). 203 204 Xanthan gum provides important stabilization of calcium carbonate particles by keeping them in 205 suspension (Frizzel and Loosemore 2010). Without the additional characteristics of the xanthan gum 206 surfactant, the insoluble calcium carbonate would settle out of solution, eliminating the opaque character 207 of the mixture and sunscald prevention and resulting in a product that could be difficult to apply as a 208 liquid. 209 210 The primary purpose for the inclusion of humic acid is to enhance plant absorption of nutrients, which is 211 facilitated through chelation and facilitated cation exchange (USDA 2012). 212 213 Status 214 215 Historic Use: 216 There has been no historic use of calcium acetate in organic agricultural production. 217 218 Calcium acetate has been used as a soil amendment in conventional agricultural production as a soil 219 amendment. Calcium acetate provides plant nutrition by delivery of the micronutrient calcium (Ca2+) in a 220 water soluble, bioavailable form, especially important in high pH soils. Calcium acetate also provides a 221 method of pH adjustment. Due to its properties, the acetate anion neutralizes acids and raises pH. Calcium 222 acetate is also used as a mixture with calcium carbonate and the surfactant xanthan gum as an opaque 223 aqueous mixture applied to plants to prevent sunscald and regulate temperature. 224 225 Organic Foods Production Act, USDA Final Rule: 226 Calcium acetate is not listed in the Organic Foods Production Act of 1990 (OFPA) or the U.S. Department of 227 Agriculture (USDA) organic regulations, 7 CFR Part 205. 228 229 International: 230 231 Canadian General Standards Board Permitted Substances List 232 Calcium acetate is not listed in the CAN/CGSB-32.311-2015 — Organic production systems - permitted 233 substances lists. 234 235 CODEX Alimentarius Commission, Guidelines for the Production, Processing, Labelling, and 236 Marketing of Organically Produced Foods (GL 32-1999) 237 Calcium acetate is not listed in the CODEX. 238 239 European Economic Community (EEC) Council Regulation, EC No. 834/2007 and 889/2008 240 Calcium acetate is not listed in the EEC EC No. 834/2007 or 889/2008. 241 242 Japan Agricultural Standard (JAS) for Organic Production 243 Calcium acetate is not listed in the JAS.

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244 245 International Federation of Organic Agriculture Movements (IFOAM) 246 Calcium acetate is not listed in IFOAM. 247 248 Evaluation Questions for Substances to be used in Organic Crop or Livestock Production 249 250 Evaluation Question #1: Indicate which category in OFPA that the substance falls under: (A) Does the 251 substance contain an active ingredient in any of the following categories: copper and sulfur 252 compounds, toxins derived from bacteria; pheromones, soaps, horticultural oils, fish emulsions, treated 253 seed, vitamins and minerals; livestock parasiticides and medicines and production aids including 254 netting, tree wraps and seals, insect traps, sticky barriers, row covers, and equipment cleansers? (B) Is 255 the substance a synthetic inert ingredient that is not classified by the EPA as inerts of toxicological 256 concern (i.e., EPA List 4 inerts) (7 U.S.C. § 6517(c)(1)(B)(ii))? Is the synthetic substance an inert 257 ingredient which is not on EPA List 4, but is exempt from a requirement of a tolerance, per 40 CFR part 258 180? 259 260 Calcium acetate falls under category A and is petitioned for use as a mineral for the delivery of calcium 261 ions (Ca2+). Calcium acetate provides a water-soluble, bioavailable form of the micronutrient essential for 262 plant structure and regulation (Bennett 1993, Frizzel and Loosemore 2010, Helper 2005, Hirschi 2004, 263 Marschner 1995). 264 265 Evaluation Question #2: Describe the most prevalent processes used to manufacture or formulate the 266 petitioned substance. Further, describe any chemical change that may occur during manufacture or 267 formulation of the petitioned substance when this substance is extracted from naturally occurring plant, 268 animal, or mineral sources (7 U.S.C. § 6502 (21)). 269 270 Calcium acetate is most commonly manufactured by the neutralization of acetic acid with calcium 271 carbonate (limestone) or calcium hydroxide (hydrated lime) (EPA 2010a, Hawley 2016). 272 273 Acetic acid is a naturally occurring substance, although most acetic acid is commercially synthesized. Most 274 acetic acid is produced through methanol carbonylation such as the CativaTM process, where methanol and 275 carbon dioxide are reacted in the presence of an iridium catalyst (EFSA 2012, Jones 2000, Sunley and 276 Watson 2000). Acetic acid is separated from other byproducts of the reaction by distillation, affording the 277 substance as glacial acetic acid in >99% purity (EFSA 2009, EFSA 2012, Jones 2000, Sunley and Watson 278 2000). 279 280 Calcium carbonate is a naturally occurring mineral that is prevalent in the earth’s crust in forms such as 281 limestone, chalk, and marble, and is isolated through mining operations (USDA 2018). It is also found in 282 shells (USDA 2018). Calcium carbonate (CaCO3) is isolated from its ground mineral sources through the 283 process of calcination (heating to high temperatures in air), resulting in the loss of CO2 gas to produce 284 quicklime (calcium oxide (CaO)) as seen in Equation 3 (Domingo et al. 2004). 285 heat CO 2+ 2- 2+ 2- + CO Ca 3 Ca O 2

calcium carbonate calcium oxide carbon dioxide (impure, from mineral deposits)

286 Equation 3 287 The resulting quicklime undergoes the slaking process (hydration of the resulting calcium oxide (CaO) by 288 the controlled addition of water) to produce slaked lime (calcium hydroxide (Ca(OH)2)) as shown in 289 Equation 4 (Domingo et al. 2004, Hassibi 1999, IUPAC 2014). 290

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2+ 2- + O Ca2+ Ca O - - H H OH OH

calcium oxide water calcium hydroxide

291 Equation 4 292 Finally, pure calcium carbonate (CaCO3) is generated via the carbonation (the addition of CO2) of slaked 293 lime, reforming purified calcium carbonate (CaCO3) as shown in Equation 5 (Domingo et al. 2004, EFSA 294 2011). 295 2+ + CO + O Ca CO2 Ca2+ 2- - - 3 H H OH OH

calcium carbonate calcium hydroxide carbon dioxide water (pure)

296 Equation 5 297 Calcium hydroxide (hydrated lime) is obtained from the same naturally occurring mineral deposits as 298 calcium carbonate (limestone, chalk, marble, oyster shells), and is isolated by calcination of the mineral 299 (Equation 3) followed by slaking (hydrating) (Equation 4) to yield calcium hydroxide (Ca(OH)2) (Al Omari 300 et al. 2016, Domingo et al. 2004). 301 302 The petitioned substance is manufactured by the neutralization of acetic acid with calcium carbonate 303 (Equation 1) or calcium hydroxide (Equation 2). In both reactions, the calcium acetate product is obtained 304 by filtration (removal of residual insoluble calcium carbonate or calcium hydroxide) and the filtrate is 305 spray dried to yield crystals or power (EFSA 2012). 306 307 Evaluation Question #3: Discuss whether the petitioned substance is formulated or manufactured by a 308 chemical process, or created by naturally occurring biological processes (7 U.S.C. § 6502 (21)). 309 310 Commercially available calcium acetate is manufactured through chemical processes (EFSA 2009, EFSA 311 2012, EPA 2010a, Hawley 2016). Calcium acetate is synthesized by the neutralization of acetic acid with 312 calcium carbonate (Equation 1) or calcium hydroxide (Equation 2) (EFSA 2009, EFSA 2012, EPA 2010a, 313 Hawley 2016). 314 315 Commercially available acetic acid is produced by methanol carbonylation using the CravitaTM process 316 (Jones 2000, Sunley and Watson 2000). While calcium carbonate and calcium hydroxide are naturally 317 occurring substances, the commercially available forms are predominantly manufactured from processing 318 the same mineral feedstocks (e.g., including limestone, dolomite, calcite, chalk) (Al Omari et al. 2016, 319 Domingo et al. 2004). Both calcium salts are derived from naturally found minerals, primarily limestone 320 and chalk (USDA 2018). Calcium hydroxide is formed through the calcination of these mineral sources, 321 followed by a slaking process (Al Omari et al. 2016, Domingo et al. 2004, EFSA 2011, Hassibi 1999). Calcium 322 carbonate is manufactured by the carbonation (addition of CO2) of calcium hydroxide (Al Omari et al. 2016, 323 Domingo et al. 2004, EFSA 2011, Hassibi 1999, IUPAC 2014). 324 325 Evaluation Question #4: Describe the persistence or concentration of the petitioned substance and/or its 326 by-products in the environment (7 U.S.C. § 6518 (m) (2)). 327 328 There are no published studies on the environmental persistence of calcium acetate. Calcium acetate may 329 be present in the metabolic cycles of animals; therefore, no risk is posed to the environment (EFSA 2012, 330 EPA 2010a, EPA 2010b). The EPA has placed calcium acetate on the Safer Chemical Ingredients List (SCIL) 331 for processing aids and additives as a safer replacement for traditional ingredients (EPA 2018). Moreover, 332 the EPA has designated calcium acetate as “verified to be of low concern based on experimental and

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333 modeled data,” and has “not identified any toxic endpoints for birds, plants, aquatic, or soil organisms” 334 (EPA 2010b, EPA 2018). 335 336 Evaluation Question #5: Describe the toxicity and mode of action of the substance and of its 337 breakdown products and any contaminants. Describe the persistence and areas of concentration in the 338 environment of the substance and its breakdown products (7 U.S.C. § 6518 (m) (2)). 339 340 There are no published studies on the environmental impacts of calcium acetate; however, the EPA has 341 “not identified any toxic endpoints for birds, plants, aquatic, or soil organisms” (EPA 2010b). 342 343 Calcium acetate acts as a water-soluble and bioavailable source of calcium, especially important in soils 344 with high pH (Borchert 1986, Frizzel and Loosemore 2010, Peacock 2005). The petitioned substance also 345 acts to increase the pH of the soil via acid neutralization of the basic acetate anion. When used as 346 petitioned, the substance also provides protection from sunscald as well as acts as a mechanism for 347 regulating plant temperature due to the opaque nature of the applied liquid (Frizzel and Loosemore 2010). 348 Once introduced into agricultural soils, the salt may result in several different outcomes, including 349 absorption by plants, reacting with acidic chemicals in the soil, or dissolving and entering water systems, 350 depending on the environmental conditions of the soil. 351 352 Evaluation Question #6: Describe any environmental contamination that could result from the 353 petitioned substance’s manufacture, use, misuse, or disposal (7 U.S.C. § 6518 (m) (3)). 354 355 As discussed for Evaluation Questions #4 and #5, there are no published studies on the environmental 356 impact of calcium acetate. Calcium is an essential mineral for plant function, and in the water-soluble form, 357 calcium acetate will be absorbed by plants. This makes environmental contamination unlikely (Bennett 358 1993, Frizzel and Loosemore 2010, Helper 2005, Hirschi 2004, Marschner 1995). Furthermore, when used as 359 petitioned, the final aqueous mixture will contain quantities that are lower than those approved for use as a 360 pesticide (~5% vs. ~20%) (EPA 2010b, USDA 2017). However, due to the limited quantities of calcium 361 acetate, and the limited environmental exposure (applied as an insecticide within a closed container that 362 attracts the insects), toxicological studies were not required for pesticide approval (EPA 2010b). 363 364 If used improperly (e.g., overapplication, improper disposal) the petitioned substance could result in water 365 pollution due to its high level of water solubility; however, the EPA has “not identified any toxic endpoints 366 for birds, plants, aquatic, or soil organisms” (EPA 2010b). Moreover, overapplication may result in over 367 adjustment of soil pH due to the presence of both calcium acetate and calcium carbonate and could result 368 in increased soil alkalinity. 369 370 The greatest potential for environmental impact is likely to occur in the isolation of precursors (calcium 371 carbonate and calcium hydroxide) for calcium acetate production. These calcium salts are derived from 372 minerals generally accessed through mining. The mining of the minerals could result in contamination 373 from natural contaminants and spills, disruption of the existing ground water, surface water, and 374 subterranean ecosystems (USDA 2018, USGS 2001, USGS 2008). 375 376 Evaluation Question #7: Describe any known chemical interactions between the petitioned substance 377 and other substances used in organic crop or livestock production or handling. Describe any 378 environmental or human health effects from these chemical interactions (7 U.S.C. § 6518 (m) (1)). 379 380 The petitioned substance is known to bind phosphates (Nolan et al. 1990). The binding action of 381 phosphates by calcium acetate could result in the inability for plants to access this nutrient source, resulting 382 in the formation of an insoluble, and biologically inaccessible, calcium phosphate salt. The propensity to 383 bind phosphate groups will result in a reaction with the improper use/storage of phosphoric acid, which 384 has been approved as “an equipment cleaner” at 7 CFR 205.603(a). However, this is unlikely to occur, given 385 that phosphoric acid is approved “provided that no direct contact with organically managed livestock or 386 land occurs,” as stated at §205.603(a). 387

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388 The petitioned substance is not known to react with other substances approved for use in organic crop or 389 livestock production. 390 391 Evaluation Question #8: Describe any effects of the petitioned substance on biological or chemical 392 interactions in the agro-ecosystem, including physiological effects on soil organisms (including the salt 393 index and solubility of the soil), crops, and livestock (7 U.S.C. § 6518 (m) (5)). 394 395 The petitioned substance increases the bioavailable concentration of calcium, resulting in increased 396 absorption by plants and microorganisms. This effect is coupled with the pH adjustment and increased soil 397 alkalinity. The ability of calcium acetate to increase soil alkalinity and pH combats acidic soils that are 398 produced from the application of nitrogen-based fertilizers, which have been documented to result in 399 unintentional fertilization through ammonia and ammonium migration (Erisman et al. 2008). The 400 unintentional migration of ammonia-based fertilizers has been linked with soil acidification and negative 401 impacts on soil microorganisms and earthworms, providing an important need for counterbalancing (pH 402 and alkalinity increasing) substances (Geisseler and Scow 2013, Kirchmann et al. 1994, Peacock 2005, USDA 403 2001a, Yadvinder-Singh and Beauchamp 1988). Calcium acetate has also been documented to sequester 404 aluminum (Al3+), which is toxic to plants and microorganisms as the free ions in acidic soil (Ma et al. 2001, 405 Nolan et al. 1990). 406 407 When used as petitioned, the calcium acetate mixture may also include humic acid, which has been shown 408 to increase the bioavailability and plant absorption of micronutrients and fostering growth of soil 409 microorganisms (Albuzio et al. 1989, Cook 1988, Lee and Bartlett 1976, Piccolo et al. 1992, USDA 2012). 410 411 Evaluation Question #9: Discuss and summarize findings on whether the use of the petitioned 412 substance may be harmful to the environment (7 U.S.C. § 6517 (c) (1) (A) (i) and 7 U.S.C. § 6517 (c) (2) (A) 413 (i)). 414 415 As discussed in Evaluation Questions #4 and #5, there are no published studies on the environmental 416 impact of calcium acetate. Calcium acetate is a naturally occurring substance that is commonly found in the 417 diet of humans and animals, and is readily metabolized (EFSA 2009, EFSA 2012). The EPA has “not 418 identified any toxic endpoints for birds, plants, aquatic, or soil organisms,” and the prevalence of 419 organisms that metabolize calcium acetate makes its environmental accumulation and contamination 420 unlikely (EFSA 2009, EPA 2010b, EFSA 2012). Furthermore, when used a petitioned, the final aqueous 421 mixture will contain quantities that are lower than those approved for use as a pesticide (~5% vs. ~20%) 422 (EPA 2010b, USDA 2017). 423 424 Evaluation Question #10: Describe and summarize any reported effects upon human health from use of 425 the petitioned substance (7 U.S.C. § 6517 (c) (1) (A) (i), 7 U.S.C. § 6517 (c) (2) (A) (i)) and 7 U.S.C. § 6518 426 (m) (4)). 427 428 Calcium acetate is a common component of human diet and is readily metabolized (EFSA 2012). Calcium 429 acetate has a long history of use in food products for “physical, nutritional, or other technical effects,” and 430 is considered safe at any concentration consistent with achieving these effects (EFSA 2012). Calcium acetate 431 has been authorized for human consumption without limitation by the Joint FAO/WHO Expert 432 Committee on Food Additives (JECFA) and the European Union Scientific Committee on Food (SCF) 433 (JECFA 1974, JECFA 1998, SCF 1990). Furthermore, the FDA has granted calcium acetate GRAS status as a 434 “sequestrant,” at 21 CFR 582.6185 and a “direct food substance,” at §184.1185. The EPA has placed calcium 435 acetate on the Safer Chemical Ingredients List (SCIL) for processing aids and additives as a safer 436 replacement for traditional ingredients (EPA 2018). Moreover, the EPA has designated calcium acetate as 437 “verified to be of low concern based on experimental and modeled data” (EPA 2018). 438 439 Evaluation Question #11: Describe all natural (non-synthetic) substances or products which may be 440 used in place of a petitioned substance (7 U.S.C. § 6517 (c) (1) (A) (ii)). Provide a list of allowed 441 substances that may be used in place of the petitioned substance (7 U.S.C. § 6518 (m) (6)). 442

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443 Calcium carbonate provides an alternative to the petitioned substance, with the ability to act as a soil 444 amendment, pH adjuster, micronutrient source, and for sunscald prevention. Calcium carbonate is 445 included in the final formulation of the calcium acetate mixture and is primarily responsible for sunscald 446 protection due to its low water solubility (Frizzel and Loosemore 2010, Piskolczi et al. 2004). Calcium 447 carbonate is the major and active component of traditional mineral applications (e.g., limestone, marble, 448 calcite) which provide both a source of the micronutrient calcium, and a mechanism for adjusting soil pH 449 (USDA 2018). However, when used alone, calcium carbonate provides limited action as both a 450 micronutrient and pH adjuster due to its low-water solubility. The addition of the petitioned calcium 451 acetate to traditional calcium carbonate-based applications increases the water solubility of the calcium 452 cation (Ca2+) and the effectiveness of the formulation in terms of micronutrient delivery and soil pH 453 adjustment. 454 455 There are a range of substances that could be used in place of the petitioned substance for specific 456 applications. For use as a micronutrient (calcium) source, minerals high in calcium (e.g., limestone, marble, 457 calcite) may be applied (USDA 2018). Due to the basic nature of these minerals (calcium carbonate (CaCO3) 458 is the major component), they also provide a mechanism for pH adjustment of soil (USDA 2018). However, 459 the effectiveness of these applications is limited by the low solubility of the calcium salts present. 460 461 Another alternative is the application of approved chelating agents to improve the bioavailability of 462 existing calcium sources in the soil. Lignin sulfonate, or lignosulfonate, is a synthetic chelating agent that is 463 approved by the NOP for use in organic agricultural production, at 7 CFR 205.601. Lignosulfonates can 464 form chelates with cationic micronutrients, increasing their water solubility and bioavailability (USDA 465 2011). Humic acids have also been shown to increase plant absorption of micronutrients, while also 466 promoting the growth of soil microorganisms (Albuzio et al. 1989, Cook 1988, Piccolo et al. 1992, USDA 467 2012). 468 469 Additionally, sodium carbonate (Na2CO3) and potassium bicarbonate (KHCO3) are capable of pH 470 adjustments and, due to their water solubility, provide a more suitable alternative to calcium acetate than 471 calcium carbonate mineral sources, calcium hydroxide, and lime sulfur (PubChem 10340, PubChem 472 516893). 473 474 Evaluation Question #12: Describe any alternative practices that would make the use of the petitioned 475 substance unnecessary (7 U.S.C. § 6518 (m) (6)). 476 477 An alternative soil amendment to the petitioned substance is the use of a compost program. Organic 478 compost includes micronutrients, natural chelates, and microbes that produce natural chelating agents 479 (Adeleke et al. 2017, Chen et al. 1998, Sorrenti et al. 2012). Furthermore, Sorrenti et al. have reported that 480 compost-based treatments have been shown to enhance yield and quality of pears in calcareous soil 481 (Sorrenti et al. 2012). 482 483 As discussed in Evaluation Question #11, the application of calcium carbonate containing minerals 484 including limestone, dolomite, calcite, and ground oyster shells provide an alternative practice for both pH 485 adjustment and a source of calcium. However, these application methods are limited due to the insoluble 486 nature of the applied calcium carbonate sources (USDA 2018). 487 488 Alternative practices for sunscald protection are careful pruning to avoid exposure of the harvestable 489 material to direct sunlight (Piskolczi et al. 2004). Additionally, other means of preharvest protection from 490 sunscald include the installation of an artificial shade or an overhead sprinkling canopy (Piskolczi et al. 491 2004, USDA 2017). Any other means of providing a physical sunblock protection such as the application of 492 kaolin and other clay-based sprays may also provide alternatives for sunscald protection. 493 494 Report Authorship 495 496 The following individuals were involved in research, data collection, writing, editing, and/or final 497 approval of this report: September 14, 2018 Page 10 of 15 Technical Evaluation Report Calcium Acetate Crops

498 499 • Philip Shivokevich, Visiting Assistant Professor of Chemistry, UMASS Amherst 500 • Samantha Olsen, Technical Writer, Savan Group 501 502 All individuals are in compliance with Federal Acquisition Regulations (FAR) Subpart 3.11—Preventing 503 Personal Conflicts of Interest for Contractor Employees Performing Acquisition Functions. 504 505 References 506 507 Adeleke R, Nwangburuka C, Oboirien B. 2017. Origins, roles and fates of organic acids in soils: A review. 508 South African Journal of Botany. 108: 393-406. 509 510 Al Omari MMH, Rashid IS, Qinna N, Jaber AM, Badwan AA. 2016. Calcium Carbonate. In Profiles of Drug 511 Substances, Excipients and Related Methodology, edited by H.G. Brittain, 31-132, Elsevier Inc. Cambridge, 512 MA, USA. 513 514 Albuzio A, Nardi S, Gulli A. 1989. Plant growth regulator activity of small molecular size humic fractions. 515 Science of the Total Environment. 81-82: 671-674. 516 517 Bennett WF. 1993. Nutrient Deficiencies and Toxicities in Crop Plants. St. Paul, MN: APS Press. 518 519 Borchert R. 1986. Calcium acetate induces calcium uptake and formation of calcium-oxalate crystals in 520 isolated leaflets of Gleditsia triacanthos L. Planta. 168: 571-578. 521 522 Capot (Capot Chemical Company, LTD.) 2013. Calcium Acetate Monohydrate MSDS. [June 2018] Available 523 from https://www.capotchem.com/5743-26-0.html?gclid=CjwKCAjw9- 524 HZBRAwEiwAGw0QcWQvN2_zQM46rjAFReJLkWs- 525 Jued64ejrjw3XdkWjwAkIbYTOtIraRoCvhYQAvD_BwE 526 527 Chen L, Dick WA, Streeter JG, Hoitink HAJ. 1998. Fe chelates from compost microorganisms improve Fe 528 nutrition of soybean and oat. Plant and Soil. 200: 139-147. 529 530 Cook RJ. 1988. Biological control and holistic plant-health care in agriculture. American Journal of 645 531 Alternative Agriculture 3: 51-62. 532 533 Domingo C, Garcia-Carmona J, Loste E, Fanovich A, Fraile J, Gomez-Morales J. 2004. Control of calcium 534 carbonate morphology by precipitation in compressed and supercritical carbon dioxide media. Journal of 535 Crystal Growth. 271: 268-273. 536 537 EFSA (European Food Safety Authority). 2009. Calcium acetate, calcium pyruvate, calcium succinate, 538 magnesium pyruvate magnesium succinate and potassium malate added for nutritional purposes to food 539 supplements. The EFSA Journal. 1088: 1-25. 540 541 EFSA (European Food Safety Authority). 2011. Scientific Opinion on re-evaluation of calcium carbonate (E 542 170) as a food additive. The EFSA Journal. 9: 2318. 543 544 EFSA (European Food Safety Authority). 2012. Scientific Opinion on the safety and efficacy of acetic acid, 545 sodium diacetate and calcium acetate as preservatives for feed for all animal species. The EFSA Journal. 10: 546 2571. 547 548 EPA (United States Environmental Protection Agency). 2010a. Calcium Acetate (011470) Fact Sheet. [June 549 2018] Available from 550 https://www3.epa.gov/pesticides/chem_search/reg_actions/registration/fs_PC-011470_01-Feb-10.pdf 551

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