2 RR Case Name PC Code s Calcium Hydroxide 075601 1305

- 62

- 0 CAS #

Calcium Oxide 075604 1305

- 78

- 8

TABLE OF CONTENTS

CALCIUM HYDROXIDE / CALCIUM OXIDE

.................. 2

APPENDICES

------------------------------------------------- ------------ 10

REGISTRATION REVIEW DOCUMENT

PRODUCT CHEMISTRY, ENVIRONMENTAL FATE AN D

ECOLOGICAL EFFECTS SUMMARY FOR CALCIUM HYDROXIDE AND

CALCIUM OXIDE

Important Note on the C hemistry of Calcium Hydroxide and Calcium Oxide :

Calcium oxide (CaO) dissociates: Ca +2 + O 2

- Oxide ion is a basic entity , as when water

is added to calc ium oxide, the oxide ion reacts: O 2

- + H 2 O

-----  2OH - a nd Calcium hydroxide dissociates: Ca +2 + 2OH - Thus the chemistries of calcium oxide and hydroxide complement each other and the major entities present in aqueous medium or

soils are three : calcium ions

, oxide which in moist soil converts to hydroxide, and hydroxide from calcium hydroxide. In water the presence of these entities increases the

water har dness, and alkalinity; and pH of acidic soil increases due to the presence of hydroxide; calcium i on is ubiquitously present in the environmental media like water and

soils

. When heated calcium hydroxide converts into calcium oxide in the absence of air; in the open atmosphere, calcium hydroxide converts into calcium carbonate, another basic entity, bu t less corrosive than calcium oxide or calcium hydroxide

PCCo de: 075601/ 075604 Case No. 4065/4066

Chemical name Use patterns/use sites

Cold

- Ster/Calcium Oxide Treatment of Medical Waste Hydrated Lime(Calcium Hydroxide) MUP *

* Other use sites lis ted on the MUP label are: Paint film or coatings on inanimate surfaces, tools, walls, ceilings, floors, appliance exteriors, pipe exteriors, HVAC equipment, duck wo r k s , and other related equipment (not including: motors, fans and other moving mechanical pa rts)concrete, stones, ceramics, plastic, wood, , interiors, and exteriors, dry wall substrates in residential dwellings,3 schools, day care centers, professional offices, commercial and industrial buildings, factories, animal housing, facilities (barns, corrals, fences)and health care facilities, hospitals, medical offices, and nursing homes . Applications to interior surfaces of HVAC system should b e made during construction, assembly, or insta llation of the unit and during the period when the HVAC system is not in operation, a nd the building is unoccupied. The product is not for use in or on coatings and other antimicrobial pesticide that will be used on food contact, food preparation, or food processing surfaces.

The se chemicals were f irst registered by EPA in 1988. At present they are registered for

use as bacete riocide/ bacteriostat and use f o r medical waste treatment . Over the years

c alcium hydroxide has been approved for Section 18 registrations to control Coqui and green house fro gs in o utdoor plan ts in nurseries and residential areas, parks, hotels and

r esorts , forest habitats, and natural a reas in Hawaii (2004, 2008, 2010). Regulatory History :

Table 1: Registered Active Products for Calcium Hydroxide

EPA Reg.

Number Product Name Formulation Type % Active Ingredient Registrant

73696

- 2 Hydrated Lime Powder/MUP 96.6 Alistagen Corporation

75661

- 1 Cold

- Ster Powder 86.8 Positive Imapct Waste
Solutions, LLC

Table 2 A . Chemical Identity

Common Name Hydrated Lime

Chemical Name Calcium Hydroxide

IUPAC Name Calcium Hydroxide

Molecular Weight 74

PC Code 075601 CAS Registry Number 1305

- 62

- 0

Molecular Formula /Empirical

Formula Ca(OH) 2

Registration Review Case No. 4065

Registration Review Case Name Calcium Hydroxide

Classification: Inorganic4 Table 2 B . Chemical Identity

Common Name Calcium Oxide/slaked lime

Chemical Name Calcium Oxide

IUPAC Name Calcium Oxide

Molecular Weight 56.0

PC Code 075604 CAS Registry Number 1305

- 78

- 8

Molecular Formula /Empirical

Formula CaO

Registration R eview Case No. 5104

Registration Review Case Name Calcium Hydroxide/Calcium Oxide

Classification: Inorganic

Structures:

OH Ca +2

OH Ca +2 O 2

-

Science Findings:

Following tables summarize the science data for each dis cipline, and lists some possible data gaps.

Product Chemistry Summary

Table 3A : Physical and Chemical Properties of Calcium Hydroxide

Guideline

No. Physical and Chemical Properties Value

830.1550 Product identity and composition Refer to Table 2

830.1 600 Description of materials used to produce the product Cbi

830.1620 Description of production process Cbi

830.1650 Description of formulation process Cbi

830.1670 Discussion of formation of impurities Cbi

830.1700 Preliminary analysis Cbi

830.1750 C ertified limits Cbi

830.1800 Enforcement analytical method Cbi5 Guideline

No. Physical and Chemical Properties Value

830.1900 Submittal of samples Cbi

830.6302 Color white: MRID: 45266603

830.6303 Physical State solid; MRID 45266603

830.6304 Odor Odorless: MRID: 45266603

830.6313 Stability to sunlight, normal and

elevated temperature Stable under normal temperature and pressure; decomposes to calcium oxide at 580 o C through

loss of water

830.6314 Oxidation/Reduction: Chemical Incompatibility Readily absorb CO 2 from air forming calcium carbonate; incomp atible with maleic anhydride, phosphorous, nitroethane, nitrormethane, nitropariffins, nitropropane; all can form explosive salts with calcium hydroxide

830.6315 Flammability

Flash Point NA

830.6316 Explodability NA

830.6317 Storage Stability Waiver req uested; MRID: 45266603

830.6319 Miscibility NA

830.6320 Corrosion Characteristic Calcium hydroxide forms a corr osive solution with a pH of 12

- 12.49 when combined with water

830.6321 Dielectric breakdown voltage NA

830.7000 pH 12.4 at 25 o C

830.7050 UV/Visible absorption spectra CaO stretch 591

- 9 cm - 1

830.7100 Viscosity NA

830.7200 Melting Point Calcium hydroxide does not a true melting point

at 580 o C calcium hydroxide loses water and

converts to calcium oxide

830.7220 Boiling point It does n ot have a true BP, as it converts to CaO at

its MP.

830.7300 Density / Bulk density 2.24 g/cc o C 2

830.7370 Dissociation Constants in water Calcium hydroxide in aqueous solution at 25 o C 1

Is a strong b a se with a pK b < 0

830.7520 Particle size NA

8 30.7550 Octanol/water partition coefficient (K OW ) (Log K

ow ) NA

830.7840 Solubility in water 1730 g/L at 20 0 C; 0.185 g/100 ml at 0 o C; 0.077 g/100 ml at 100 o C

830

- 7840 Solubility in organic solvents in g/100

ml NA

830.7950 Vapor pressure It is a solid, vapor pressure is likely negligible6 Table 3B : Physical and Chemical Properties of Calcium Oxide

Guideline

No. Physical and Chemical Properties Value

830.1550 Product identity and composition Refer to Table 2 a
830.1600 Description of materials used to produce the product Cbi

830.1620 Description of production process Cbi

830.1650 Description of formulation process Cbi

830.1670 Discussion of formation of impurities Cbi

830.1700 Preliminary analysis Cbi

830.1750 Certified limits Cbi

830.1800 Enforcement analytical method Cbi

830.1900 Submittal of samples Cbi

830.6302 Color Grayish white: MRID:46052702

830.6303 Physical State solid; MRID 46052702

830.6304 Odor Odorless: MRID: 46052702

830.6313 Stability to sunlight, normal and

e levated temperature Stable under normal temperature and pressure; decomposes to calcium oxide at 580 o C through

loss of water

830.6314 Oxidation/Reduction: Chemical Incompatibility Calcium oxide reacts with water to form calcium hydroxide and heat is evo lved. It reacts violently with chlorine trifluoride and phosphorous pentoxide; MRID# 46052702

830.6315 Flammability

Flash Point NA: MRID# 46052702

830.6316 Explodability NA: MRID#: 46052702

830.6317 Storage Stability Calcium oxide is stable if stored in tightly closed plastic containers. CaO readily absorbs carbon

dioxide and water from air to become slaked.

MRID#: 46052702

830.6319 Miscibility NA: one gram of CaO is slightly soluble in 840

ml/water: MRID: 46052702

830.6320 Corrosion Characteristic Ca lcium oxide will possiblye become corrosive to

aluminum when the chemical becomes wet.:

MRID#: 46052702

830.6321 Dielectric breakdown voltage NA

830.7000 pH 12.5 ; MRID#: 46052702

830.7050 UV/Visible absorption spectra CaO stretch 591

- 9 cm - 1 MRID#: 45266603

830.7100 Viscosity Not applicable

830.7200 Melting Point No Report

830.7220 Boiling point No Report

830.7300 Density / Bulk density 3.2

- 3.34 g/cc MRID#: 56052702

830.7370 Dissociation Constants in water Not applicable

830.7520 Particl e size No Report

830.7550 Octanol/water partition coefficient (K OW ) (Log K

ow ) Not applicable

830.7840 Solubility in water 1730 g/L at 20 0 C; 0.185 g/100 ml at 0 o C; 0.077 g/100 ml at 100 o C; MRID#: 46052702

830

- 7840 Solubility in organic solvents in g/100

ml No Report

830.7950 Vapor pressure It is a solid, vapor pressure is likely negligible7 Environme ntal Fate and Transport Data Summary :

The environmental fate test guidelines (161 series) are not applicable for calciu m oxide or calcium hy d r o x i de. Calcium hydroxide and Calcium Oxide in environmental media:

In water : Calcium hydroxide is slightly solub l e in water, ~ 0 .15 g/100ml; in solution calcium hydroxide consists of: calcium ions, hydroxyl ions, with approximate pH of 12.4;

when acid is added, more calcium hydroxide dissolves. In water then, calcium hydroxide tends to increase the water hardness, and alkalinity. When base OH is added, calcium precipitates more. When heated, it interacts with atmospheric carbon dioxide to form

insolubl e calcium carbonate. W hen h e ated solid calcium hydroxide forms calcium oxide.

Calcium oxide is a solid, and interacts with water violently to form calcium hydroxide,

and large amount of heat is produced. As a solid cal cium o xide contains c al c ium ions,

a nd oxide ions.

In acidic soils : calcium oxide will increase the pH of soils by replacing aluminum through cation exchange. In most acidic soils, calcium oxide would first convert into calcium hydroxide and then liming process (raising the pH of acidic s oils) would follow. Depending on the nature of soils, and selected crop(s) each state will have a specific

recommendations for a defined capacity of calcium hydrox ide required for liming process

for soils.

Environmental Fate and Transport Conclusions :
No long term env ironmental impact is expected f r o m calcium hydroxide or calcium

oxide in water and soils from present use and use patterns.

Environmental Fate and Transport Data Gaps No environmental fate data gaps exist for calcium hydroxide or calcium oxi de for the present uses of these chemicals, and the Agency does not ant icipate requiring any additional fate data.8 Ecological Effects Data Summary :

Table 4 summarizes the eco

- toxicity d ata that AD has either in its data base or collected

f rom open literature . The studies were conducted with calcium hydroxide . These studies provided some information to characterize toxicity, but they were not reviewed and do not fulfill the data guidelines.

Table 4 Ecotoxicity Data

Guidelin e #/Study
type MRID#/Reference Information/Study

Classification Dosing/Organism

Information Results

850.1075: Fish Acute Toxicity Test ( Zambezi Barbel)

African Catfish MRID#: 45266613: : Aquacult Fish Management; Vol 21, pp 181

- 185 Ca(OH) 2 administer

for 96 hours at
10,20, 40, 80, 150 mg/L; purity not reported 96

- hour LC50: 34 mg/L

850.1075: Fish Acute Toxicity (Western Mosquito fish) MRID 45266614:. Sewage and

Industrial Wastes 29(6):695

- 711 Ca(OH) 2 administered for 96 hours; purity not reported 96 hour LC50: 160 mg/L

Invertebrate: Scud Open Literature: Yee et al. (2000) Ecotox Reference

90867 Administered for 96 hours; dosing not reported 96 hour NOAEC(mortality): 1188 mg/L; practically non

- toxic Invertebrate: Midge Open literature; Yee et al.(2000); Ecotox Reference 90867 Administered for 96 hours; dosing not reported 96 NOAEC (mortality): 1781 mg/L; practically

non

- toxic Aquatic Plants:

Blue

- green Algae Open Literature: Ecotox Reference

15018 Method of

administration not reported EC50: 66 mg/L

Ter restrial Animals:

Red

- winged

B l a ckbird Open Literature:

Richardson & Gangoli (1993) Method of

administration not reported LD50 = 111 mg/kg; moderately toxic

Mammals: Rat Richardson & Gangoli (1993) Method of

ad min i stration not reported LD50= 7340 mg/kg;

pr actically non

- toxic

Invertebrates:

Earthworm D i a z

- Lopez and Mancha (1994) Ecotox Reference

40516 48 hour LC50 LC50= 520μg/cm 29 Note: A number of studies listed in Table 4 are referenced in the section 18 (Emerg ency use of calcium hydroxide granted to Ha waii by the Agency) ; no ec otoxicity or fate

assessment were carried for this use. Some of these ecotoxicity studies were co n d u c ted on species that are not native to USA.

Ecotoxicity Conclusions :

The ecotoxicity studies in its database listed in Table 4 for calcium hydroxide appear to
be nontoxic to: western mosquito fish, slightly toxic to African catfish, which is not native of USA; non

- toxic to invertebrates like scud, and midge; for aquatic plant like

blue

- green algae only inhibition of nitrogen fixa tion is observed; it is moderately toxic to

red

- winged bl ackbird. These studies provided some information to characterize toxicity, but they were not reviewed and do not fulfill the data guidelines. These studies were not reviewed or assessed. The Agency i s requiring the following studies and anticipates to

conduct the risk assessment based on the available studies and the additional studies that the agency requested by the Agency

Ecotoxicity Data Gaps:

Since the ecotoxicity data was generated on non

- gu ideline studies, as well as the fact the species on which the studied were conducted are not native to USA, t he Agency is requiring the following ecotoxicity studies:

850.1075 Acute freshwater fish toxicity

850.1010 Acute Toxicity Freshwater invertebrat e 850. 5400 Aquatic growth, Tier II green algae10 APPENDIX A

Data justifications for ecotoxicity of Calcium Hydroxide

Guideline Number: 850.5400 Study Title: Algal toxicity (Tier II) Rationale for Requiring the Data As part o f a Tier I risk assessment, one indicator plant species is tested for phytotoxicity. This study

would allow the Agency to categorize barium calcium hydroxide/calcium oxide as toxic or non

- toxic to plants. If toxic, additional higher tier plant tests would be needed. An endangered species assessment for endangered or threatened plants is not possible without this study. Practical Utility of the Data

1. How will the data be used? This study would be used to evaluate t he toxicity of calcium hydroxide/calc ium oxide to non

- target plants in terrestrial and aquatic ecosystems. 2. How could the data impact the Agency’s future decision

- making?

Adverse effects to non

- target plants in terrestrial and aquatic ecosystems may result in mitigation to protect specie s at risk. Mitigation might include reduced label dosages, neutralization of effluents prior to discharge into water, restrictions on use in sensitive ecosystems or where endangered species are present, or other mitigation measures. 3. What is triggering the need for this data? Increased concern from state regulators and the public to evaluate impacts on WWTP operations, endangered species, and persistence in the environment, since initial registration, have triggered the need for this study. Green algae a re critical to ecosystem health and productivity.11 Guideline Number: 850.1075 Data Requirement: Acute Fish Toxicity (estuarine/marine) Rationale for Requiring the Data Sport fishing and commercial fishing have a high impact on the United States economy . The acute toxicity tests with estuarine/marine fish are designed to measure mortality during short

- term (96

- h) aquatic exposure to a range of concentrations of the pesticide in water. The preferred test species is

Atlantic silverside ( Menidia menidia ) fo r salt water. Practical Utility of the Data

1. How will the data be used?

Data would be used to determine concentration

- response curves and calculate LC50's (with 95% confidence intervals) for 24, 48, 72, and 96 h. Additionally, a NOEC for 96 h is repor ted. The

results from these studies may also provide information for a concentration

- selection rationale for fish early

- life stage study (OPPTS 850.1400) and the fish life cycle study (OPPTS 850.1500).

2. How could the data affect the risk assessment?

The re are many estuarine/marine fish species that are listed as threatened and endangered in the

United States. Although the Atlantic silverside is the preferred species, the sheepshead minnow is

considered a surrogate species to represent all marine/estuarin e fish species in the risk assessment process. As part of the acute risk assessment for aquatic animals, the lowest EC50 or LC50 for

estuarine/marine fish is used in the RQ equation. An acute RQ > 0.5 would indicate an acute LOC, defined as the potential f or acute risk to non

- target organisms which may warrant regulatory action in addition to restricted use classification. An acute RQ > 0.1 would result in an acute restricted use LOC, defined as the potential for acute risk to non

- target organisms, which ma y be mitigated through restricted use classification. An acute RQ > 0.05 would fall under the LOC for acute endangered species.
3. What is triggering the need for this data? Data are needed in order to conduct an ecological risk assessmen t for the propose d use of calcium hydroxide/calcium oxide and determ ine the acute toxicity of calcium oxide to estuarine/marine fish.12 BIBLIOGRAPHY FOR: PRODUCT CHEMISTRY, ENVIRONMENTAL FATE AND TRANSPORT, AND ECO

- EFFECTS

1. MRID#: 45266603

2. MRID#: 46052702

3. A Memo by A. Najm Shamim to Norm Cook , Chief RASSB in AD (Feb 01, 2001) (DPBarcode: D272177(S590169) On the Chemical Screening of Calcium Hydroxide

4. Section 18 Memo From Colleen Flaherty to Dan Rieder, Chief Environmental Risk Branch 3, Dec. 2004, EFED

5. Section 18, A Memo From Colleen Flaherty to Tom Bailey, Branch Chief,
EFED, June 2008

6. Diaz

- Loez et al., 1994: Ecotoxicity of Soil Organisms , Lewis Publ, Boca Raton, Florida: pp 251

- 256

7. Peterson et al., 1995: Water Research, volume 29(6), pp 1515

- 1523

8. Richardson, et al., 1993: The Dictionary of Substances and their Effects. Royal Society of Chemistry, UK

9. Ufodike, et al, 1990: Aquatic Fish Management, volume 2(2), pp 181

- 185

10. Yee et al., 2000: Canadian Journal of Fish & Aquatic Science: 57: 125

- 136