Page 2 of 48

1,3,5-Triazine-2,4-Diamine, N-Cyclopropyl-N'-(1,1-Dimethylethyl)-6-(Methylthio)- 

REGISTRATION REVIEW DECISION

PRODUCT CHEMISTRY, ENVIRONMENTAL FATE AND

 ECOLOGICAL EFFECTS SUMMARY

PC Code: 128996; Case No. 5031

Introduction: 

1,3,5-Triazine-2,4-diamine, N-cyclopropyl-N'-(1,1-dimethylethyl)-6-(methylthio)- better 

known under the trade names Irgarol® 1051 and Cybutryn is a chemical compound with a 1,3,5-

triazine ring as the basic structure. Irgarol 1051 is an odorless, low volatile, yellowish to white 

solid granule (powder) which has a low vapor pressure of 6.6 x 10-7 mmHg at 25°C, very low 

water solubility of 7 mg/L (7 ppm) and a log Pow of 3.95 at 25°C (moderately lipophilic). 

Fouling can significantly increase water resistance to boats which can result in up to 40% 

higher fuel consumption. Fouling can also decrease maneuverability (a safety hazard) and it can 

damage the ship’s body. In the process of fouling, algae form a substrate for macro-fouling. 

Irgarol 1051 is an algicide specifically designed for use in marine antifouling coatings. It is a 

highly specific and effective inhibitor of photosynthesis which can control fouling of marine 

surfaces caused by algae. Its very low water solubility contributes to very slow leaching rates and 

therefore extended antifouling action. 

In antifouling paints Irgarol 1051 is often combined with copper, or copper compounds 

such as cuprous oxide or copper thiocyanate. While Irgarol 1051 effectively controls algae, 

copper is effective at controlling animals. Irgarol 1051 is a s-triazine herbicide used in 

combination with copper in antifoulant paint as a “booster” biocide, intended to diminish algae 

growth on ship hulls. 

Products containing Irgarol 1051 as an active ingredient were first registered with the 

EPA for use in boat antifouling paints on January 1st1960. Currently, there are 41 active 

products under a single PC Code 128996 which are listed in Table 1. Registered products 

contain between 0.49 and 98.1% Irgarol 1051. The registered formulations are technical 

chemical, formulation intermediate, emulsifiable concentrate, liquid soluble concentrate, 

pressurized liquid, and ready-to-use solutions. Irgarol 1051 products are registered in 

combination with cuprous oxide (PC Code: 25601; CAS#1317-39-1), copper thiocyanate (PC 

Code: 025602; CAS# 1111-67-7), carbendazim (PC Code: 128872; CAS# 10605-21-7), 

chlorothalonil (tetrachloroisophthalonitrile) (PC Code: 81901; CAS# 1897-45-6), octhilinone 

(OIT; PC Code: 099901; CAS# 26530-20-1), 3(2H)-Isothiazolone, 4,5-dichloro-2-octyl- 

(DCOIT; PC Code: 128101; CAS# 64359-81-5), and carbamic acid, butyl, -3-iodo-2-propynyl 

ester (IPBC; PC Code: 107801; CAS# 55406-53-6). 

Irgarol 1051 is a triazine herbicide possessing biocidal activity against algal and diatom 

fouling species and is used as a 'booster biocide' in approved antifouling products for use on 
Page 3 of 48

vessels of any size and on structures below the waterline. The major use sites for these products 

include antifouling coatings for boats and materials preservatives for exterior paints, coatings, 

building materials, vinyl roofing, stucco, grouting, spackling and joint cement. (Exterior Paints, 

Coatings, Stains, Building Materials, Latex and Solvent Based Paints, Semi Transparent Stains, 

Solid Stains, Vinyl Roofing, Elastomeric Roof, Wall Coatings, Mastics, Caulks, Sealants, Joint 

Cements, Spackling, Stucco, Grouting, Applied Film of Paint, Masonry Coatings, Wood 

Protective Stains, Adhesives, Caulks and Sealants, Roof Coatings, Plasters, Sealants and Fillers 

used for Architectural Products, Finishes and Special Purpose Coatings, Hulls on Ships, Boats, 

Barges, Yachts and Running Gear). For use as a biocide in manufacturing caulking compounds, 

sealants, joint compounds, stucco, coatings, paints, dry film paint, stains, grouts, adhesives, and 

wood preservatives. An algicide and slimicide to be formulated into marine and/or freshwater 

antifoulant paints for boats and/or vessels only. 

Table 1. Registered Active Products of Irgarol

Registration # Registration Name Company Name Formulation 

Type 

% of 

Active 

Ingredient

707-304 Rocima 65 Industrial Microbicide Rohm & Haas Co. Emulsifiable 

Concentrate 3.5 

707-312 Rocima 80 Rohm & Haas Co. Soluble 

Concentrate 32.5 

1258-1270 Densil CA Arch Chemicals, Inc. Soluble 

Concentrate 6.0 

1529-38 Fungitrol 1075 International Specialty 

Products 

Formulation 

Intermediate 15.0 

1529-48 Fungitrol 2002 International Specialty 

Products 

Formulation 

Intermediate 5.89 

2693-170 Fiberglass Bottomkote With 

Biolux II - Black International Paint LLC Ready-to-Use Solution 0.49 

2693-181 Tri-Lux III With Bio-Lux 5490 

Blue International Paint LLC Ready-to-Use Solution 2.23 

2693-183 Micron CSC Plus With Biolux 

Shark White International Paint LLC Ready-to-Use Solution 1.9 

2693-189 Tri-Lux Blue International Paint LLC Ready-to-Use 

Solution 2.23 

2693-190 Micron CSC Super With Bio-Lux 

Blue International Paint LLC Ready-to-Use Solution 2.0 

2693-192 Ultra With Bio-Lux Blue International Paint LLC Ready-to-Use 

Solution 1.59 

2693-197 VC 17M With Biolux Original International Paint LLC Ready-to-Use 2.38 
Page 4 of 48

Registration # Registration Name Company Name Formulation 

Type 

% of 

Active 

Ingredient

Solution 

2693-198 VC 17M With Biolux Red International Paint LLC Ready-to-Use 

Solution 2.38 

2693-199 Trilux With Biolux Black International Paint LLC Pressurized 

Liquid 0.86 

2693-201 Ultra Plus - Blue International Paint LLC Ready-to-Use 

Solution 1.6 

2693-202 CSC Plus - Blue International Paint LLC Ready-to-Use 

Solution 2.0 

2693-204 CSC Plus - Blue International Paint LLC Ready-to-Use 

Solution 2.0 

2693-205 Ultra Plus Blue International Paint LLC Ready-to-Use 

Solution 1.59 

2693-208 Fiberglass Bottomkote With 

Biolux-Blue International Paint LLC Ready-to-Use Solution 0.98 

2693-209 Fiberglass Bottomkote Act With 

Biolux-Blue International Paint LLC Ready-to-Use Solution 0.98 

2693-212 Super Epoxycop With Irgarol - 

Blue International Paint LLC Ready-to-Use Solution 0.98 

2693-213 Super KL Plus With Irgarol - Blue International Paint LLC Ready-to-Use 

Solution 0.98 

2693-216 Prop & Drive Clear Aerosol International Paint LLC Pressurized 

Liquid 1.6 

2693-218 Fiberglass Bottomkote Act With 

Biolux II - Black International Paint LLC Ready-to-Use Solution 0.49 

2693-219 Super KL Plus With Irgarol II - 

Black International Paint LLC Ready-to-Use Solution 0.49 

2693-224 Micron Extra Blue International Paint LLC Ready-to-Use 

Solution 1.96 

5383-88 Troysan Polyphase 588 Troy Chemical Corp Emulsifiable 

Concentrate 10.0 

5383-102 Mergal S 90 Troy Chemical Corp Ready-to-Use 

Solution 4.9 

5383-105 Troysan ALF4 Troy Chemical Corp Emulsifiable 

Concentrate 10.0 
Page 5 of 48

Registration # Registration Name Company Name Formulation 

Type 

% of 

Active 

Ingredient

5383-108 Polyphase 662 Troy Chemical Corp Soluble 

Concentrate 4.0 

9339-31 Aquagard II Antifouling Spray 

Paint For Outdrive & Outboards Flexabar Corp Ready-to-Use Solution 0.8 

40810-11 Irgarol 1051 Ciba Corporation Technical 

Chemical 98.1 

40810-15 Irgarol 1071 Ciba Corporation Ready-to-Use 

Solution 98.1 

44891-13 

Sea Hawk Premium Quality 

Tropikote Biocide Plus Slime 

Resistant Antifouling Coating 

New Nautical Coatings 

Inc. 

Ready-to-Use 

Solution 2.02 

44891-14 

Sea Hawk Premium Quality 

Cukote Biocide + Slime Resis. 

Antifoul. Coat. 

New Nautical Coatings 

Inc. 

Ready-to-Use 

Solution 2.0 

60061-94 Pettit Marine Paint Ultima SR 

Biocide Antifouling Kop-Coat, Inc. Ready-to-Use Solution 2.0 

60061-95 Petit Marine Paint Trinidad SR 

Antifouling Kop-Coat, Inc. Ready-to-Use Solution 2.0 

60061-110 Petit Marine Paint SR-21 Fresh 

Water Antifouling Kop-Coat, Inc. Ready-to-Use Solution 2.0 

60061-117 Pettit Marine Paint Ultima SR 

Antifouling Paint Kop-Coat, Inc. Ready-to-Use Solution 2.0 

74681-4 Copper Pro SCX 67 Bluewater Marine Paint Ready-to-Use 

Solution 1.96 

74681-6 Copper Shield SCX 45 Bluewater Marine Paint Ready-to-Use 

Solution 1.96 

Use Patterns: 

707-304: 

Industrial Microbicide for Use in Exterior Paints, Coatings, and Building Materials. 

Coatings: for use as a microbiocide to control bacteria, algae and fungi in exterior paints, 

coatings, and stains. 

Building Materials: For use as a microbiocide to control bacteria, algae and fungi in exterior 

building materials, stucco, caulks, and sealants. 

May not be used for food grade coatings or adhesives that may come in contact with food. 
Page 6 of 48

707-312: 

Algicide for Use in Coatings and Building Materials. 

Coatings: For use as an algicide to control algae in non-food use/non-food contact coatings such 

as latex, and solvent-based paints, semi-transparent stains and solid stains. 

Building Materials: For use as an algicide to control algae in building materials such as vinyl 

roofing, elastomeric roof and wall coatings and mastics, caulks, sealants, joint cements, 

spackling, stucco, and grouting. 

The manufactured products are for outdoor use only, are not to be used in products that my come 

in contact with water, and are not to be used on wood or any other treated material which is to be 

used for food, feed, potable water, livestock, dairy animals or living plants. 

1258-1270: 

For the Control of Fungal and Algal Growth on Exterior Paints, Caulks, Stucco and Stains. 

It is an aqueous dispersion of a broad spectrum fungicide in combination with a broad spectrum 

algaecide, for control of fungal and algal growth on exterior paints, caulks, stucco, and stains. It 

provides excellent characteristics when used as a fungicide/algaecide in aqueous systems only, 

such as latex emulsion paints, stains, and coatings, stucco, and caulks. 

Like natural substrates, coatings (if unprotected) can be susceptible to the growth of a wide range 

of fungi and algae. The uncontrolled growth of these organisms can lead to failure of coatings for 

their intended purpose of protecting expensive substrates. It is an effective fungicide/algaecide 

which provides long term protection from fungal and algal defacement of the paint film. 

Some critical advantages of it are: synergistic biocidal action of the active agents, hydrolytic 

stability, extremely low water solubility, low vapor pressure, fine particle size, excellent pH 

stability, and endurance to UV radiation.

Mode of Action: 

2,4,5,6-Tetrachloroisophthalonitrile is a multisite protective fungicide. The mode of action is the 

binding of the active molecule to the glutathion moiety, thus preventing completion of the energy 

cycle of the fungal species, and ultimately controlling fungal growth. Unlike many other 

systemic fungicides, this is not a site specific activity. Hence there is no known resistance to the 

fungal control.

N-Cyclopropyl-N'-(1,1-dimethylethyl)-6-(methylthio)-1,3,5-triazine-2,4-diamine is a broad 

spectrum algaecide, it has activity against both fresh water and sea water algae. The mode of 

action of this active agent is that of an inhibitor of photosynthesis. 

An effective fungicide/algaecide in most aqueous products.

It is the responsibility of the manufacturer to test DENSIL CA for optimum dosage levels and to 

determine compatibility and suitability for intended use. 
Page 7 of 48

It is recommended that DENSIL CA be added during or after letdown stage. If desired DENSIL 

CA can be added as a post-add to the finished paint. This is especially useful for base paints. It is 

important to ensure thorough mixing of DENSIL CA into the formulated paint. 

When an in-can preservative is used in .combination with DENSIL CA, it should be tested first 

for compatibility. DENSIL CA is compatible with latex paints containing zinc oxide. Further 

information is available from our Technical Service personnel. 

1529-38: 

FOR INDUSTRIAL USE ONLY 

FUNGITROL 1075 is intended only for protecting the applied film of paint, coating, stucco, 

stain and caulk itself from algal growth. It is not intended to protect the substrate to which the 

preserved material is applied. Products that incorporate FUNGITROL® 1075 in their 

manufacture, may not make claims on their labels regarding protection of the substrate from 

algal growth. 

An algicide for use in the manufacture of the following aqueous and solvent compositions only: 

paints, coatings, stucco, stains and caulks to protect the applied paint film, coating, stucco, stain 

and caulk itself from algal growth. The manufactured products are for outdoors uses only, are not 

to be used in products that may come in contact with water, and are not to be used on wood or 

any other treated material which is to be used for food, feed, potable water, livestock, dairy 

animals or living plants. 

1529-48: 

FOR INDUSTRIAL USE ONLY 

For use as a biocide in manufacturing caulking compounds, sealants, joint compounds, stucco, 

coatings, paints, dry film paint, stains, grouts, adhesives, and wood preservatives. 

2693-170: 

Irgarol Improves Antifouling Performance by Reducing Slime. 

Proven All Purpose Antifouling Protection. 

It is a hard modified-epoxy antifouling paint that provides excellent season long protection. It 

contains cuprous oxide and Irgarol. The Irgarol works to control weed, slime and algae fouling 

while cuprous oxide works to control shell fouling such as barnacles and Zebra mussels. This 

keeps the bottom of boat cleaner longer. 

2693-181: 

Formulated for Use on Aluminum, Fiberglass or Wood 

Slime Resistance 

Contains Petroleum Distillates 

Antifoulant paint for use on aluminum boats, outdrives and outboards. 
Page 8 of 48

Cuprous thiocyanate works against shell fouling such as barnacles and zebra mussels while 

Irgarol prevents slime and algae growth. 

Do Not Apply Above True Waterline. 

2693-183: 

Irgarol Controls Slime 

Use on fiberglass, wood and steel hulls. 

Irgarol Improves Antifouling Performance by Reducing Slime. 

Contains cuprous oxide 

Cuprous oxide works against shell fouling and Irgarol protect against weed, slime, and algae 

growth. 

For use below waterline on fiberglass, wood and properly primed metal, boat hulls and parts, in 

fresh, salt and brackish waters. 

Do not use on aluminum. 

This product contains cuprous oxide and Irgarol. The Irgarol works to control weed, slime and 

algae fouling while the cuprous oxide works to control shell fouling such as barnacles and zebra 

mussels. This keeps the bottom of your boat cleaner longer. It provides excellent protection 

against all forms of marine fouling in waters with moderate to heavy fouling and can be used in 

fresh, salt and brackish waters. 

2693-189: 

Biolux Blocks Slime. Biolux boosts performance by controlling slime. It is a hard antifouling 

paint specifically developed for use on aluminum boats, outdrives and outboards. It uses a resin 

system containing two biocides - Cuprous Thiocyanate and an organic bàoster called Biolux. The 

Cuprous Thiocyanate works best against shell fouling such as barnacles and zebra mussels while 

the Biolux booster helps prevent slime and algae growth. This blend of resins and biocides offer, 

when properly applied over primer, excellent antifouling protection. It has been specifically 

developed for use on primed aluminum, but it can also be applied to fiberglass, wood and other 

underwater metals on boats. It is for use below the waterline in fresh, salt and brackish water. It 

can be applied by brush, roller or spray. V.O.C.: Less than 400 grams /liter (3.34 lbs/gallon). 

2693-190: 

Biolux Blocks Slime. Biolux boosts performance by controlling slime. Biolux® is a multiseason, controlled solubility copolymer antifouling paint that is specially formulated with two 

biocides - cuprous oxide and a booster called Biolux®. The cuprous oxide works best against 

shell fouling, while the Biolux® booster helps protect against weed, slime and algae growth. 

2693-192: 

Contains Biolux to resist slime. High copper antifouling for ultimate protection. Teflon® added 

for durability and easy cleaning. Biolux boosts antifouling performance by controlling slime. 

Biolux resists slime. Contains petroleum distillates, xylene or xylene range aromatic solutions. 

Provides excellent long-term protection from shell and weed fouling. Ultra with Blolux® 

contains a very high loading of Cuprous Oxide and uses Biolux® technology to control slime. 
Page 9 of 48

2693-197: 

Biolux Blocks Slime. Biolux Boosts Performance by Controlling Slime. Complete protection 

against zebra mussels, teredo worms, weed, algae and slime fouling. This is especially helpful in 

freshwater or low fouling saltwater. 

2693-198: 

Biolux Blocks Slime. Biolux Boosts Performance by Controlling Slime. Complete protection 

against zebra mussels, teredo worms, weed, algae and slime fouling. This is especially helpful in 

freshwater or low fouling saltwater. 

2693-199: 

Control slime growth. For use in fresh, salt and brackish water. 

2693-201: 

Resist slime. Control Slime. Long term protection from shell and weed fouling. 

Best against shell fouling such as barnacles and zebra mussels and works to control slime and 

algae fouling. Can be used in fresh, salt and brackish water on fiberglass, wood and properly 

primed metal boat hulls and parts. Do not use on aluminum. 

2693-202: 

Blocks Slime. Control slime. Works against shell fouling, protect against weed, slime and algae 

growth. 

2693-204: 

Blocks Slime. Control slime. Works against shell fouling, protect against weed, slime and algae 

growth. 

2693-205: 

Resist Slime. Control slime. Best against shell fouling such as barnacles and zebra mussels and 

works to control slime and algae fouling. Can be used in fresh, salt and brackish water on 

fiberglass, wood and properly primed metal boat hulls and parts. Do not use on aluminum. 

2693-208: 

Control slime. Works to control weed, slime and algae fouling and control shell fouling such as 

barnacles and zebra mussels. 

2693-209: 

Fight slime. Works to control shell fouling such as barnacles and zebra mussels. Can be used in 

fresh, salt and brakish waters. 

2693-212: 

Blocks Slime. Control slime. Anti slime additive. Antifouling protection against barnacles, 

zebra mussels, hydroids, algae and slime for boats in salt or fresh water on boat bottoms. 
Page 10 of 48

2693-213: 

Use in high fouling salt or fresh water areas. Algaecide. Provides resistance to barnacles, slime, 

algae and hydroids. 

2693-216: 

Prop & Drive Clear Aerosol antifouling paint is formulated specifically for aluminum outboards, 

outdrives and aluminum hulls in underwater areas. Prop & Drive Clear Aerosol dries quickly so 

that it can be painted and launched the same day. Prop & Drive Clear Aerosol uses Biolux® 

Technology to control slime growth. Prop & Drive Clear Aerosol is for use in fresh, salt and 

brackish water. Prop & Drive Clear Aerosol also contains Teflon® for added durability and easy 

cleaning. 

FOR ALUMINUM OUTBOARDS, OUTDRIVES AND HULLS 

Do not apply primer or Prop & Drive Clear Aerosol above the true waterline. 

Do not apply to tin-based paint such as Micron®33, Micron 33 Aerosol, Micron 44 or Tri-Lux 

lIT. Do not use above the true waterline. 

2693-218: 

Reduces slime 

Fights slime 

The lrgarol works to control weed, slime and algae fouling while the cuprous oxide works to 

control shell fouling such as barnacles and zebra mussels. 

It provides excellent protection against all forms of marine fouling in waters with moderate to 

heavy fouling and can be used in fresh, salt and brackish waters. 

A multi-season, antifouling paint that is formulated with two biocides that provides effective 

protection against barnacles, slime, algae and hydroids. It is recommended for boats that are used 

in high fouling salt or fresh water areas, or which remain in the water for prolonged periods 

between haul outs. 

It is for use below the waterline on fiberglass, wood and properly primed metal boat hulls and 

parts, in fresh, salt and brackish waters. 

2693-219: 

Contain Organic Boosting Biocide to Combat Slime. 

Contain a Specially Formulated Boosting Algaecide to Combat Slime. 

Use on wood, fiberglass and steel hulls. 

Provides effective protection for boats that are used in high fouling salt or fresh water areas, or 

which remain in the water for prolonged periods between haul outs. The high load of cuprous 

oxide and a specially formulated boosting algaecide provides excellent resistance to barnacles, 

slime, algae and hydroids. 

Resistant to algae, barnacles and other marine fouling. 
Page 11 of 48

Blocks slime growth. 

2693-224: 

Blocks slime. 

Boosts Performance by Controlling Slime. 

Antifouling Protection for All Conditions. 

Contains Petroleum Distillates 

5383-88:

A Fungicide/Algicide For Exterior Paints, Masonry Coatings, Wood Protective Stains, 

Adhesives, Caulks and Sealants. 

Sold for industrial use only in the final use products: Exterior paint, wood protective stain, 

adhesives, caulks & sealants, Joint cements, roof coatings, and stucco. 

5383-102: 

Industrial Biocide for Use in Paints, Coatings, Plasters, Stuccos, Sealants, Caulks and Fillers. 

An antimicrobial preservative for control of fungi and algae growing on paints, coatings, 

plasters, sealants, and fillers used for architectural products, finishes and special purpose 

coatings. 

5383-105: 

A Preservative for Exterior Paints and Coatings, Wood Protective Stains, Adhesives, Caulks and 

Sealants and Exterior Plaster Coatings. 

Applications: Paints and stains, wood protective stain, adhesives, caulks, grouts and sealants, 

stucco. 

5383-108: 

A Broad Spectrum Biocide for use in Exterior Paint and Stains, Masonry Coatings, Adhesives, 

Caulks and Sealants, Roof Coatings, Stucco and Joint Cements. 

It is a water dispersion of biocides effective against a wide variety of fungal and algal organisms. 

Its primary application is in water-based products where VOC is a major concern. 

It is not to be used in formulations intended for food contact paper coatings or food contact 

adhesive uses. 

It should be added to paints and coatings, exterior paints, wood protective stains, masonry 

coatings, and roof coatings at the end of the manufacturing cycle, after the final pH adjustment 

has been made. 
Page 12 of 48

It may be added to exterior caulks and sealants at the end of the production cycle with good 

agitation. 

It may be added to stucco and to joint cements. 

9339-31: 

Contains cuprous thiocyanate. 

Outboard & lower unit anti-fouling paint. 

Controls slime & other fouling organisms. 

For use on aluminum & other non-ferrous materials. 

Ideal for use on stern drives and other lower units. 

40810-11 

An Algicide/Slimicide for Use In Formulating Antifouling Paints. 

For Industrial Use Only. 

An algicide and slimicide to be formulated into marine and/or freshwater antifoulant paints for 

boats and/or vessels only. 

40810-15 

An Algicide for Use in the Manufacturing of the Following Aqueous and Solvent Compositions 

Only: paints, coatings, stucco, stains and caulks to inhibit or control the growth of algae on 

the treated surfaces. 

An algicide for use in the manufacture of the following aqueous and solvent compositions only: 

pants, coatings, stucco, stains and caulks to inhibit or control the growth of algae on the treated 

surfaces. The manufactured products are for outdoor use only, are not to be used in products that 

may come in contact with water, and are not to be used on wood or any other treated material 

which is to be used for food, feed, potable water, livestock, dairy animals or living plants. 

44891-13: 

Biocide Plus Slime Resistant Antifouling Coating. 

Hard epoxy-based antifoulant with over 73% copper in every color. This product is designed to 

control barnacles, algae and other marine foulings in salt or fresh water. This product is designed 

for use on the surfaces of hulls on ships, boats, barges, yachts, or running gear. 

44891-14: 

Biocide Plus Slime Resistant Antifouling Coating. 
Page 13 of 48

Ablative, self-polishing antifoulant. This product is designed to control barnacles, algae and 

other marine foulings in salt or fresh water. This product is designed for use on the surfaces of 

hulls on ships, boats, barges, yachts, or running gear. 

60061-94: 

Marine Paint 

Oblative Dual Biocide Antifouling Bottom Paint 

• High copper content. 

• Multi-season technology. 

• Self-polishing. 

• Reduces paint build-up through controlled erosion. 

• Excellent for fiberglass, wood & steel boats. 

• Slime resistant. 

Commercial and Non-Commercial Use 

Do No Apply this Product on Aluminum Hulls or Outdrives. 

Marine Paint 

60061-95: 

Antifouling Bottom Paint 

• Slime resistant. 

• Very high copper content. 

• Long-term protection. 

• Effective In worst tropical conditions. 

Hard finish, easily burnished. 

• Excellent for fiberglass, wood and steel boats. 

COMMERCIAL AND PRIVATE CONSUMER USE 

60061-110: 

Marine Paint 

Fresh water antifouling Paint 

• Super Slick Finish 

• Dual- Biocide Controls Hard and Soft Fouling 

• Ultra-Thin Film Thickness Prevents Paint Build-Up 

• Contains Moly-Disulfide & PTFE for Reducing Friction 

• No Sanding Required 

• Excellent for Fiberglass, Wood and Steel Boats 

THIS PRODUCT IS A TWO-COMPONENT PRODUCT. 

TO ONLY BE MIXED WITH POWDER PORTION 

LOCATED UNDER THE LID OF THIS CONTAINER 

BEFORE USING. 

60061-117: 

Marine Paint 

Slime resistant. 

Multi-season technology 
Page 14 of 48

Self-polishing. 

Reduces paint build-up through controlled erosion 

Excellent for fiberglass, wood & steel boats. 

COMMERCIAL AND NON-COMMERCIAL USE 

DO NOT USE THIS PRODUCT ON ALUMINUM HULLS OR OUTDRIVES 

74681-4: 

Contains cuprous oxide 

Marine Paint 

Slime control 

Tremendous Protection for Extreme Fouling Conditions. 

It provides extended antifouling protection against barnacles, algae and hydroids in salt and fresh 

water on boat bottoms only. It acts like a sunscreen to prevent slime and algae. Its ablative 

copolymer base renders a smooth- finish with durability and abrasion resistance. It releases 

biocide by the constant exposure of new paint film to the water. It has universal application over 

all types of properly prepared bottom paints (except aluminum). For use on fast fiberglass boats, 

as well as wood and steel hulls, extended protection is possible, since performance is directly 

proportional to the amount of paint applied. 

Do not use on aluminum. 

For use on boats below the true waterline. 

74681-6: 

Contains cuprous oxide 

Marine Paint 

Slime control 

It provides extended antifouling protection against barnacles, algae and hydroids in salt and fresh 

water on boat bottoms only. It acts like a sunscreen to prevent slime and algae. Its ablative 

copolymer base renders a smooth- finish with durability and abrasion resistance. It releases 

biocide by the constant exposure of new paint film to the water. It has universal application over 

all types of properly prepared bottom paints (except aluminum). For use on fast fiberglass boats, 

as well as wood and steel hulls, extended protection is possible, since performance is directly 

proportional to the amount of paint applied. 

Do not use on aluminum. 
Page 15 of 48

Science Findings

The Agency has conducted a review of the available product chemistry, environmental 

fate, and ecotoxicity data for Irgarol 1051. The findings are summarized below. 

Product Chemistry Summary 

 The data submitted pertaining to the physical and chemical characteristics of the active 

ingredient Irgarol 1051 are adequate. All product chemistry data requirements have been 

fulfilled for the active ingredient Irgarol 1051. Therefore, the Agency does not anticipate 

needing additional product chemistry data for Irgarol 1051 at this time. Tables 2 and 3 contain 

the complete product chemistry information for the active ingredient Irgarol 1051. 

Table 2. Chemical Identity of Irgarol 1051 

Chemical Name 1,3,5-Triazine-2,4-diamine, N-cyclopropyl-N'-(1,1-

dimethylethyl)-6-(methylthio)- 

Common Names N-Cyclopropyl-N'-(1,1-dimethylethyl)-6-(methylthio)-

1,3,5-triazine-2,4-diamine 

Synonyms 2-(tert-Butylamino)-4-(cyclopropylamino)-6-

(methylthio)-1,3,5-triazine 

s-Triazine, 2-(tert-butylamino)-4-(cyclopropylamino)-6-

(methylthio)- 

2-(tert-Butylamino)-4-(cyclopropylamino)-6-

(methylthio)-s-triazine 

Cybutryne 

Irgarol 

Trade Name Irgarol 1051 

Irgarol 1071 

IUPAC Name 2-methylthio-4-tert-butylamino-6-cyclopropylamino-striazine 

N'-tert-butyl-N-cyclopropyl-6-(methylthio)-1,3,5-

triazine-2,4-diamine 

Molecular Weight 253.37 g/mole 

PC Code 128996 

CAS Registry Number 28159-98-0 

Molecular Formula C11H19N5S

Registration Review Case No. 

Registration Review Case Name 

5031 

1,3,5-Triazine-2,4-diamine, N-cyclopropyl-N'-(1,1-

dimethylethyl)-6-(methylthio)- 
Table 2. Chemical Identity of Irgarol 1051 

Chemical Family Thio 

Triazine 

Amine 

Cyclo 

Molecular Structure: 

Table 3. Product Chemistry Data Summary of Irgarol 1051 (TGAI 98.1%) 

Page 16 of 48

Guideline No. Physical and Chemical 

Properties 

Value 

830.1550 Product identity and 

composition 

Refer to Table 2. 

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 

HPLC and Gas Chromatography 

830.1900 Submittal of samples NA 

830.6302 Color Yellowish to white granules 

830.6303 Physical State Solid granules 

830.6304 Odor No odor. No distinguishable odor. 

830.6313 Stability to sunlight, normal 

and elevated temperature, 

metals/metal ions 

Stable under normal and elevated temperatures. Not sensitive to 

metal. Does not degrade. 

No decomposition expected under normal storage conditions.

Stability: Stable. 
Page 17 of 48

Guideline No. Physical and Chemical 

Properties 

Value 

The product is not sensitive to metal ions and metal. 

830.6314 Oxidation/Reduction: 

Chemical Incompatibility 

No oxidizing or reducing agents in product. 

Based upon chemistry of this product, it is neither an oxidizing nor 

reducing agent. 

Incompatibility: Strong oxidizing agents, strong acids, strong 

bases. 

830.6315 Flammability Data not required; product is not a combustible liquid. 

Flash point: > 200°C (392°F) 

830.6316 Explodability Data not required; product contains no explosive ingredient 

830.6317 Storage Stability Unchanged 

830.6319 Miscibility Data not required; product is not an emulsifiable liquid. 

830.6320 Corrosion Characteristics During storage, no change in packaging material was observed. 

During storage of this product in various types of material, 

including PVC, plastic, cardboard, aluminum, and tinplates, no 

change in the packaging material was observed. 

830.6321 Dielectric breakdown 

voltage 

Data not required.

830.7000 pH Data not required; product not dispersible with water 

830.7050 UV/visible light absorption 

830.7100 Viscosity Data not required; product is not a liquid. 

830.7200 Melting point 127-130°C 

Decomposition Temperature: > 200°C (392°F) 

830.7220 Boiling point Data not required. 

N.A. 

830.7300 Density Sp Gr 1.10 (H20 =1) 

830.7370 Dissociation Constant Data not relevant. 

5.16 Mean value @pH 4-6 

830.7550 Partition coefficient (noctanol/water) log Pow 3.95 at 25°C 

830.7840 Solubility in water 7 ppm @ 20-25oC 

830.xxxx Solubility in organic 

solvents 

Organic solvent, g/100 ml

Xylene, 5.0 

Shell—sol A, 8.0 

Solvent naphtha, 5.0 

Butyl acetate, 15.0 

Methyl isobutyl ketone, 12.0 

Butylene glycol, 15.0 

Propylene glycol, 1.0 

Octanol, 5.0 

Methyl cellosolve, 10.0 

830.7950 Vapor pressure 6.6 x 10-7 torr at 25°C (77oF) 

Nitrosamines Less than 0.12 ppm 

N/A = Not applicable; TGAI=Technical Grade Active Ingredient; CBI= Confidential Business Information 
Page 18 of 48

Environmental Fate Summary 

The Agency has reviewed eleven environmental fate studies for Irgarol 1051. The 

submitted environmental fate studies were all found to be acceptable. The environmental fate 

guideline studies and the results are summarized in Table 6. The chemical structures and 

identities of degradates are listed in Table 7. The Agency's conclusions for the degradation, 

metabolism, mobility, bioaccumulation, and special leaching studies are as follows. 

a. Degradation Studies (Abiotic) 

Hydrolysis: Irgarol 1051 not hydrolyze in either sterile aqueous buffered solutions at pH 

5, 7, and 9 or in sterile synthetic seawater at pH 8. Irgarol 1051 was hydrolytically stable. 

Photodegradation in Water: Irgarol 1051 is stable to photodegradation in sterile, buffered 

pH 7 water and in sterile synthetic seawater at pH 8. At pH 7 sterile buffered solution it has a 

photolytic half-life of 148 days when calculated through least square regression and 723 days if 

calculated by conventional method; at pH 8 sterile buffered seawater solution its half life is 273 

days through least square regression and becomes 281 days when calculated by conventional 

methods. It is a persistent and stable molecule in aqueous medium. 

b. Metabolism Studies (Biotic) 

Aerobic Soil Metabolism: The aerobic soil metabolism ha1f-1ife was 101 days in sandy 

1oam soi1. Three metabolism degradates were identified in the aerobic soil metabolism study; 

GS 26575 (half life: 273 days), GS 28620 (half life: 273 days), and CA 30-0155 (half life: 122 

days). The parent (Irgarol 1051) and its degradates are essentially stable and resistant to 

microbes. 

Aerobic Aquatic Metabolism: Under aerobic aquatic conditions, Irgarol 1051 degraded 

with half-lives of >800 days in the marine loamy sand sediment:seawater slurry system and 192 

days in the loamy sand sediment:lake water (freshwater) slurry system. These data indicate that 

Irgarol 1051 is stable and not readily metabolized in sediment/water systems incubated under 

aerobic conditions. Three metabolism degradates were identified in the aerobic aquatic 

metabolism study; GS 26575, CGA 234576, and CA 30-0156. 

Anaerobic Aquatic Metabolism: Under anaerobic aquatic conditions, half-1ives were 

2050 and 8503 days for flooded 1oamy sand sediment: freshwater and loamy sand sediment: 

seawater systems, respectively. These data indicate that Irgarol 1051 may be extremely 

persistent in marine/estuarine sediments. Irgarol 1051 is stable and not readily metabolized in 

sediment/water systems incubated under anaerobic conditions. No degradates were found in the 

anaerobic aquatic metabolism study. 

In summary, Irgarol 1051 does not readily metabolize in soi1:water systems. Irgarol 1051 

was stable towards aerobic soil, anaerobic aquatic (freshwater and seawater), and aerobic aquatic 
(freshwater and seawater) metabolism. The results of these studies do clearly demonstrate that 

Irgarol 1051 is persistent in the environment. 

c. Mobility Studies 

Adsorption/Desorption: Unaged lrgarol moderately adsorbs to soil/sediment particles. 

The mobility of lrgarol was studied using four soils, a freshwater sediment, and a saltwater 

sediment. Freundlich Kads values ranged from 2.59 in a sand to 7.12 in a clay loam which 

indicate moderate mobility in soil systems while Kdes ranged between 2.34 to 7.65 which shows 

that Irgarol gets desorbed from soil systems quite easily (Table 4). The percent lrgarol adsorbed 

to the test soils ranged from 21.2% for the sand to 43.3% for the clay loam. Both adsorption and 

desorption K values strongly point toward the possibility that the molecule is moderately mobile 

in the soil system and has a potential of leaching to ground water and runoff to surface water. 

Moreover, equilibrium batch studies of the Irgarol degradates, namely CA-30-0228, CA-30-

0232, and CA-30-0155 have been conducted for various soil types. These studies indicate that 

Kads for CA-30-0228 ranges from 1.10 to 3.38 while Kdes varies from 1.83 to 5.32; and for the 

degradate CA-30-0232, Kads varies from 0.716 to 3.38 while Kdes ranges from 0.296 to 0.962. 

All these values indicate that the two degradates are highly mobile in the soil systems and may 

pose a problem of ground water contamination and surface water run off. For degradate CA-30-

0155 Kads is between 1.52 to 6.17 while Kdes are between 15.6 to 17.3, a strong indication that it 

is not released from the soil system easily. 

Table 4. Adsorption/Desorption of Irgarol 1051 in Soil 

d. Bioconcentration Study: 

Bioaccumulation in Fish: Fish accumulation data demonstrated that Irgarol 1051 

accumulated in blue gill sunfish with maximum mean bioconcentration factors o f 62x, 290x, and 

160x for edible, nonedible, and whole fish tissues, respectively. In the edible tissues, Irgarol 

1051 was the major residue identified. In the viscera, the degradate CGA 234576 predominated. 

Depuration was rapid, with 62, 92, and 85% of the accumulated [14C] residues eliminated from 

the edible, nonedible, and whole fish tissues, respectively, by day 14 of the depuration period 

(Table 5). Strong indication that most of the pesticide does not stay in the tissues. 

Page 19 of 48
Table 5. Bioconcentration and Elimination by Bluegill Sunfish (Lepomis macrochirus)

e. Antifoulant Special Leaching Studies: 

Leach rate test of 16 end-use products (boat bottom antifoulant paints) established release 

rates ranging from 0.24 to 16.6 ug Irgarol 1051/cm2

/day. 

Table 6. Environmental Fate Data Summary for Irgarol 1051 

OPP 

Guideline Fate Studies Half-Life Degradates Study Status 

161-1 Hydrolysis (Buffer) 

pH 5 

pH 7 

pH 9 

Stable None. Acceptable

161-1 Hydrolysis (Seawater) 

pH 8 Stable None. Acceptable

161-2 

Photolysis (Buffer) 

pH 7 

Stable 

148 days (by least squares 

regression) or 

723 days (by conventional 

methods) 

None. 

Acceptable

161-2 Photolysis (Seawater) 

pH 8 

Stable 

273 days (by least sq. regression) 

or 

281 days (by conventional 

method)

None. Acceptable

162-1 

Aerobic Soil 

Metabolism 

Stable/Persistent 

Not Readily Metabolized 

101 days in sandy loam soil

(calculated) 

Half-life of Degradates:

GS 26575: 273 days 

GS 28620: 273 days 

CA 30-0155:122day 

GS 26575 

GS 28620 

CA 30-0155 

Acceptable

Page 20 of 48
Page 21 of 48

OPP 

Guideline Fate Studies Half-Life Degradates Study Status 

162-3 Anaerobic Aquatic 

Metabolism 

(sediment:freshwater 

and 

sediment:seawater) 

Stable/Persistent 

Not Readily Metabolized 

2050 days (freshwater) 

8503 days (Seawater) 

None 

Acceptable

162-4 Aerobic Aquatic 

Metabolism 

(sediment:freshwater 

and 

sediment:seawater) 

Stable/Persistent 

Not Readily Metabolized 

192 days (freshwater) 

>800 days (Seawater) 

GS 26575 

CGA 234576 

CA 30-0156 

Acceptable

163-1 

Leaching and 

Adsorption/Desorption 

Irgarol 1051 does not readily 

adsorb to soil particles and has 

moderate mobility in soils

Soil Type Kads Kdes %ads

sand 2.59 2.34 21.2 

loamy 

sand 

(freshwater 

sediment) 

3.12 4.22 24.6 

silt loam 6.29 7.95 40.5 

loamy 

sand 

(marine 

sediment) 

6.93 7.08 42.5 

sandy 

loam 

6.56 7.65 41.1 

clay loam 7.12 6.53 43.3 

Acceptable

163-1 

Equilibrium batch 

studies (degradates) 

Degradates Kads Kdes

CA 30-0228 1.10- 

3.38 

1.83- 

5.32 

CA 30-0232 0.716-

3.38 

0.296-

0.962 

CA 30-0155 1.52-

6.17 

15.6-

17.3 

Acceptable
Page 22 of 48

OPP 

Guideline Fate Studies Half-Life Study Degradates Status 

165-4 

Bioaccumulation in 

Bluegill sunfish 

Fish

Tissues

Mean

BCF

Depuration 

(14 days)

Edible 62x 62% 

Non 

edible 

290x 82% 

Whole 

body 

fish 

tissue 

160x 85% 

Irgarol 1051 does not stay 

in the tissues. 

No 

Bioaccumulation 

No 

bioconcentration 

Acceptable

ASTM 

D5108–

90 

Antifoulant Leach 

Rate Test 

Release rates ranging from 

0.24 to 16.6 ug Irgarol 

1051/cm2/day 

Acceptable

Table 7. Degradates of Irgarol 1051 

N'-(1,1-dimethylethyl)-6-(methylthio)-1,3,5-triazine-2,4-diamine 

(M1) (parent minus cyclopropyl group) 

N'-(1,1-dimethylethyl)-1,3,5-triazine-2,4-diamine 

(parent minus methylthio and cyclopropyl groups)

N-Cyclopropyl-N'-(1,1-dimethylethyl)-1,3,5-triazine-2,4-diamine 

(parent minus thiomethyl group)

4-[(1,1-dimethylethyl)amino-6-(cyclopropylamino)-1,3,5-

triazine-2-(1H)-one 

(parent minus thiomethyl group replaced with hydroxyl group) 
Table 7. Degradates of Irgarol 1051 

(parent minus cyclopropyl and methylthio groups with 

substituted hydroxyl in place of methylthio) 

(parent minus cyclopropyl, dimethylethyl, and thiomethyl 

groups with hydroxyl group in place of methylthio) 

(parent minus dimethylethyl group with oxygenated methylthio 

group) 

CA 30-0228 

2-amino-4-methylthio-6-t-butylamino-s-triazine 

(parent minus cyclopropyl group)

The Agency did not conduct an environmental fate assessment for Irgarol 1051. However, 

the Agency needs to conduct an environmental fate assessment for material preservatives used in 

exterior paints, coatings, and building materials that potentially pass through waste water treatment 

plants (WWTPs) and may be discharged into terrestrial and aquatic environments. Also, the Agency 

anticipates conducting an environmental fate assessment for Irgarol 1051 used in wood preservatives 

(outdoor)) and antifouling coatings. For this assessment the Agency anticipates needing those data 

outlined on page 30 of this document. 

Water Quality 

Irgarol 1051 is not identified as a cause of impairment for any water bodies listed as impaired under 

section 303(d) of the Clean Water Act, based on information provided at 

http://iaspub.epa.gov/tmdl_waters10/attains_nation_cy.cause_detail_303d?p_cause_group_id=885 . 

 In addition, no Total Maximum Daily Loads (TMDL) have been developed for Irgarol 1051, based 

on information provided at 

http://iaspub.epa.gov/tmdl_waters10/attains_nation.tmdl_pollutant_detail?p_pollutant_group_id=885

&p_pollutant_group_name=PESTICIDES . More information on impaired water bodies and TMDLs 

can be found at http://www.epa.gov/owow/tmdl/. The Agency invites submission of water quality 

data for this pesticide. To the extent possible, data should conform to the quality standards in 

Appendix A of the OPP Standard Operating Procedure: Inclusion of Impaired Water Body and 

Other Water Quality Data in OPP’s Registration Review Risk Assessment and Management Process

 (see: http://www.epa.gov/oppfead1/cb/ppdc/2006/november06/session1-sop.pdf ), in order to ensure 

they can be used quantitatively or qualitatively in pesticide risk assessments. 

Page 23 of 48
Page 24 of 48

Ecological Effects Summary 

The Agency has reviewed 43 ecotoxicology studies for Irgarol 1051. The 43 studies 

submitted on the 88.54 - 100% Irgarol 1051 and its degradates were all found to be acceptable 

for use in a hazard assessment. Ecotoxicity guideline studies and the results are summarized in 

Table 6. The Agency's conclusions for the avian and aquatic effects studies are as follows. 

• Irgarol 1051 is practically non-toxic to avian species in the diet and by single oral dose 

ingestion. 

• Irgarol 1051 is highly toxic to moderately toxic to freshwater fish on an acute basis. 

• Irgarol 1051 causes chronic toxic effects on freshwater fish at low levels (9 ppb). 

• Irgarol 1051 is moderately to slightly toxic to freshwater aquatic invertebrates on an 

acute basis. 

• Irgarol 1051 causes chronic toxic effects on freshwater invertebrates at levels as low as 

560 ppb. 

• Irgarol 1051 is moderately toxic to estuarine/marine fish on an acute basis. 

• Freshwater fish early life-stage testing show that Irgarol 1051 causes chronic toxic effects 

on marine/estuarine fish at levels as low as 330 ppb.

• Irgarol 1051 is highly to moderately toxic to estuarine/marine invertebrates on an acute 

basis. The degradates are moderately toxic. 

• Marine/estuarine invertebrate life-cycle testing results show that Irgarol 1051 causes 

chronic toxic effects on marine/estuarine invertebrates at levels as low as 250 ppb. 

• Irgarol 1051 is very highly toxic to algae and aquatic plants. The major degradates are 

less toxic, but are still predominantly in the highly toxic range.

Whole Sediment Acute Invertebrate, Freshwater and Marine/Estuarine (OPPTS 850.1735) 

 The data generated during this study established that freshwater amphipod survival was 

not affected by exposure to lrgarol 1051 at a nominal concentration of 120 mg a.i./kg sediment. 

The Lowest-Observed-Effect Concentration (LOEC) for Irgarol 1051 was > 120 mg a.i./kg 

sediment. The No-Observed-Effect Concentration (NOEC) established for this study was 120mg 

a.i./kg sediment. 

Whole Sediment Acute Invertebrate, Freshwater and Marine/Estuarine (OPPTS 850.1740) 
Page 25 of 48

 The data generated during this study established that marine/estuarine amphipod survival 

was not affected by exposure to Irgarol 1051 at a nominal concentration of 240 mg a.i./kg 

sediment. The Lowest-Observed-Effect Concentration (LOEC) for Irgarol 1051 was 240mg 

a.i./kg sediment. The No-Observed-Effect Concentration (NOEC) established for this study was 

120 mg a.i./kg sediment. 

Bioavailability/Bioaccumulation (OPPTS 850.1730)

 Bioavailability/bioaccumulation testing was required for Irgarol due to its persistence in 

water and sediments and potential for cumulative effects (Kow of 2399). A fish bioconcentration 

factor study on Irgarol was submitted; results of this test are provided below: 

Maximum BCF of 62X, 290X and 160X for edible, non-edible and whole fish 

tissues, respectively. Depuration for 14 days resulted in elimination of 62%, 92% 

and 85% for these same tissues, respectively. 

The results show that Irgarol does not significantly bioconcentrate in fish tissues. The 

Guideline for fish bioaccumulation (850.1730/old 72-6/165-4) is fulfilled. 

Estuarine and Marine Field Studies (OPPTS 850.1950)

 A marine microcosm was submitted to the Agency to address the rate of degradation of 

Irgarol 1051 from seawater under quasi-natural conditions (light, temperature, evaporation, 

precipitation, measure the partitioning of Irgarol 1051 between seawater and sediment and 

measure the change in toxicity to algae as Irgarol 1051 degrades from seawater. Irgarol 1051 

dissipated from the microcosm water with an approximate 23-day half-life. The metabolite GC 

26575 accumulated for the first 30 days of the study, and then declined at the same rate of Irgarol 

1051, a 23-day half-life. Neither the parent compound nor the metabolite accumulated in the 

sediment. Irgarol 1051 was toxic to the marine diatom (71% growth inhibition after 21 days), 

Skeletonema costatum, at the high concentrations found in the beginning of the study (nominal 

concentration of 560 ng a.i./L). However, as the Irgarol 1051 concentration declined over the 

first 57 days of the study (measured concentrations of 31 and 44 ng a.i./L), so did the growth 

inhibition of the test diatom (9.0 and 10% growth inhibition at 57 days, declining to 0% 

inhibition at 77 days) . The study was classified as acceptable, fulfilling Guideline 850.1950/old 

72-7. 

Table 8. Ecotoxicity Data Summary for Irgarol 1051 (TGAI) and Irgarol 1051 Degradates

CHEMICAL GUIDE 

LINE 

COMMON 

NAME 

TAXONOMIC 

NAME 

TEST 

TYPE

% 

AI 

STUDY

TIME 

DOSE

TYPE TOXICITY TOX LEVEL NOEL TOX CATEGORY 

Avian Acute Oral Toxicity

Irgarol 

1051

850.2100 

71-1

Bobwhite 

quail

Colinus 

virginianus

O 98 14 D LD50 >2250 MGK 810 Core 

Practically 

non-toxic

Avian Subacute Dietary Toxicity

Irgarol 580.2200 Bobwhite Colinus D 98 8 D LC50 >5620 PPM 1780 Core
Page 26 of 48

CHEMICAL GUIDE 

LINE 

COMMON 

NAME 

TAXONOMIC 

NAME 

TEST 

TYPE

% 

AI 

STUDY

TIME 

DOSE

TYPE TOXICITY TOX LEVEL NOEL TOX CATEGORY 

1051 71-2a quail virginianus Practically 

non-toxic

Irgarol 

1051

580.2200 

71-2b

Mallard 

duck

Anas 

platyrhynchos

D 98 8 D LC50 >5620 PPM 1000 Core

Practically 

non-toxic

Freshwater Fish Acute Toxicity

Irgarol 

1051

850.1075 

72-1a

Bluegill 

sunfish

Lepomis 

macrochirus

S 98.6 96 hr LC50 2.6 PPM <1.0 Core

Moderately 

toxic

Irgarol 

1051

850.1075 

72-1c

Rainbow 

trout

Oncorhynchus 

mykiss

S 98.6 96 hr LC50 0.84 PPM <0.26 Core 

Highly toxic

Irgarol 

1051

850.1075 

72-1c

Rainbow 

trout

Oncorhynchus 

mykiss

F 98.6 96 hr LC50 0.75 PPM <0.15 Core 

Highly toxic

Freshwater Fish Early Life-Stage (Chronic)Toxicity

Irgarol 

1051

850.1400 

72-4a

Rainbow 

trout

Oncorhynchus 

mykiss

F 98 95 D LOEC 0.009 PPM 0.004 Core 

Chronic toxic 

effects

Freshwater Invertebrate Acute Toxicity

Irgarol 

1051

850.1010 

72-2 

Water flea Daphnia 

magna

S 98.6 24 hr EC50 66 PPM 7.8 Supplemental

Moderately 

toxic

Irgarol 

1051

850.1010 

72-2 

Water flea Daphnia 

magna

S 98 48 hr EC50 5.3 PPM 0.3 Core 

Slightly toxic

Freshwater Invertebrate Life-Cycle (Chronic) Toxicity

Irgarol 

1051

850.1300

72-4b

Water flea Daphnia 

magna

F 99 21 D LOEC <0.56 PPM <0.56 Supplemental 

Chronic toxic 

effects 

Estuarine/Marine Fish Acute Toxicity

Irgarol 

1051

850.1075 

72-3 

Sheepshead 

minnow

Cyprinodon 

variegatus

F 98 96 hr LC50 3.5 PPM 0.82 Core

Moderately 

toxic

Irgarol 

1051

850.1075 

72-3 

Inland 

silverside

Menidia 

beryllina

S 98 96 hr LC50 1.58 PPM 0.6 Core

Moderately 

toxic

Irgarol 

1051 

(GS26575 

degradate)

850.1075 

72-3 

Sheepshead 

minnow

Cyprinodon 

variegatus

S 100 96 hr LC50 11.0 PPM 5.2 Core

Moderately 

toxic

Irgarol 

1051 

(GS28620 

degradate)

850.1075 

72-3 

Sheepshead 

minnow

Cyprinodon 

variegatus

S 88.54 96 hr LC50 >13 PPM 13 Core

Moderately 

toxic

Irgarol 

1051

CA30-0155 

degradate)

850.1075 

72-3a 

Sheepshead 

minnow

Cyprinodon 

variegatus

S 93.4 96 hr LC50 >4.6 PPM >4.6 Core

Moderately 

toxic

Estuarine/Marine Fish Early Life-Stage Toxicity
Page 27 of 48

CHEMICAL GUIDE 

LINE 

COMMON 

NAME 

TAXONOMIC 

NAME 

TEST 

TYPE

% 

AI 

STUDY

TIME 

DOSE

TYPE TOXICITY TOX LEVEL NOEL TOX CATEGORY 

Irgarol 

1051

850.1400 

72-4a 

Sheepshead 

minnow

Cyprinodon 

variegatus

F 99 33 D LOEC 0.33 PPM 0.17 Supplemental

Chronic toxic 

effects

Estuarine/Marine Bivalve (Oyster) Acute Toxicity (embryo larval) - Invertebrates

Irgarol 

1051

850.1055 

72-3b 

Eastern 

oyster 

EmbLrv

Crassostrea 

virginica

S 98.6 48 hr EC50 3.2 PPM 0.76 Core

Moderately 

toxic

Estuarine/Marine Mysid Acute Toxicity - Invertebrates

Irgarol 

1051

850.1035 

72-3

Mysid Americamysis 

bahia

S 98.6 96 hr LC50 0.40 PPM <0.13 Core 

 Highly toxic

Irgarol 

1051 

(GS26575 

degradate)

850.1035 

72-3

Mysid Americamysis 

bahia

S 100 96 hr LC50 1.5 PPM 0.88 Core 

Moderately 

toxic 

Irgarol 

1051 

(GS28620 

degradate)

850.1035 

72-3

Mysid Americamysis 

bahia

S 88.54 96 hr LC50 >13 PPM 13 Core 

Slightly toxic

Irgarol 

1051 

(CA300155 

degradate)

850.1035 

72-3 

Mysid Americamysis 

bahia

S 93.4 96 hr LC50 >6.0 PPM 3.9 Core

Moderately 

toxic

Estuarine/Marine Mysid Life-Cycle (Chronic) Toxicity - Invertebrates

Irgarol 

1051

850.1350 

72-4b

Mysid Americamysis 

bahia

F 98 28 D LOEC 0.26 PPM 0.11 Core 

Chronic toxic 

effects

Freshwater/Marine Invertebrate Irgarol-Treated Sediment Acute Toxicity

Irgarol 

1051

850.1735 

73-1

Freshwater 

Amphipod 

Hyalella 

azteca

SR 99 10 D LOEC

LC50

>120 

sedimt

MGK 120 Core 

Survival was 

not affected

Irgarol 

1051

850.1740 

73-2

Marine 

Amphipod 

Ampelisca 

abdita

SR 99 10 D LOEC

LC50

>240 

sedimt

MGK 120 Core 

Survival was 

not affected

Aquatic Vascular Plant Toxicity 

Irgarol 

1051

850.4400

123-2

Duckweed Lemna gibba S 98.2 14 D EC50 1.6 PPB 0.67 Core

Algal toxicity 

Irgarol 

1051 

850.5400 

123-2 

Freshwater 

Bluegreen 

algae 

Anabaena 

flos-aquae 

S 98.2 5 D EC50 1.9 PPB 0.5 Core 

Detrimental 

effects 

Irgarol 

1051 

850.5400 

123-2 

Freshwater 

Green 

algae 

Selenastrum 

capricornutum

S 98.2 5 D EC50 1.3 PPB <0.65 Core 

Detrimental 

effects 

Irgarol 

1051 

850.5400 

123-2 

Marine 

diatom 

Skeletonema 

costatum 

S 98.2 5 D EC50 0.45 PPB 0.14 Core 

Detrimental 

effects 

Irgarol 850.5400 Freshwater Scenedesmus S N.R. 72 hr EC50 2.4 PPB 0.74 Suppl 
Page 28 of 48

CHEMICAL GUIDE 

LINE 

COMMON 

NAME 

TAXONOMIC 

NAME 

TEST 

TYPE

% 

AI 

STUDY

TIME 

DOSE

TYPE TOXICITY TOX LEVEL NOEL TOX CATEGORY 

1051 123-2 Green 

algae 

subspicatus Detrimental 

effects 

Irgarol 

1051 

850.5400 

123-2 

Freshwater 

Green 

algae 

Selenastrum 

capricornutum

S N.R. 72 hr EC50 1.47 PPB <1.0 Suppl 

Detrimental 

effects 

Irgarol 

1051 

850.5400 

123-2 

Freshwater 

diatom 

Navicula 

pelliculosa 

S 98.2 5 D EC50 0.1 PPB <0.05 Core 

Detrimental 

effects 

Irgarol 

1051

850.5400 

123-2

Green 

algae

Chlorococcum 

sp.

S 99.6 5 D EC50 0.42 PPB 0.10 Supplemental 

Detrimental 

effects

Irgarol 

1051 

850.5400 

123-2 

Goldenbrown alga Isochrysis 

galbana 

S 99.6 5 D EC50 0.44 PPB 0.11 Supplemental 

Detrimental 

effects 

Irgarol 

1051

850.5400 

123-2

Green 

algae

Dunaliella 

tertiolecta

S 99.6 5 day EC50 0.56 PPB 0.13 Supplemental 

Detrimental 

effects

Irgarol 

1051 

(GS26575 

degradate)

850.5400 

123-2

Freshwater 

diatom

Navicula 

pelliculosa

S 100 5 D EC50 0.19 PPM <0.077 Core 

Detrimental 

effects

Irgarol 

1051 

(GS28620 

degradate)

850.5400 

123-2

Freshwater 

diatom

Navicula 

pelliculosa

S 88.54 5 D EC50 14 PPM 1.3 Core

Irgarol 

1051 

(CA30-

0155 

degradate)

850.5400 

123-2

Freshwater 

diatom

Navicula 

pelliculosa

S 93.41 5 D EC50 100 PPB 10 Core 

Detrimental 

effects

Irgarol 

1051 

(GS26575 

degradate)

850.5400 

123-2

Marine 

diatom

Skeletonema 

costatum

S 99.94 5 D EC50 0.016 PPM 0.00018 Core 

Detrimental 

effects

Irgarol 

1051 

(GS28620 

degradate)

850.5400 

123-2

Marine 

diatom

Skeletonema 

costatum

S 88.54 5 D EC50 >21 PPM 1.2 Core

Irgarol 

1051 

(CA30-

0155 

degradate)

850.5400 

123-2

Marine 

diatom

Skeletonema 

costatum

S 93.41 5 D EC50 81 PPB 13 Supplemental 

Detrimental 

effects

Ecotoxicity data are adequate to provide the Agency with sufficient information to 

determine appropriate label precautions. 
Page 29 of 48

Ecological Effects Risk Assessment 

An ecological risk assessment was not conducted on the Irgarol 1051 use patterns 

described in this document. Irgarol 1051 uses that have potential for environmental exposure are 

exterior or outdoor uses of material preservatives (in exterior paints, coatings, and building 

materials). The Agency needs to conduct environmental fate and ecological risk assessments for 

exterior or outdoor uses of material preservatives that potentially pass through waste water 

treatment plants (WWTPs) and may be discharged into terrestrial and aquatic environments. 

Also, the Agency needs to conduct an ecological risk assessment for Irgarol 1051 used in wood 

preservatives and antifouling coatings. For this ecological risk assessment, including an 

endangered species assessment for all uses, the Agency anticipates needing the ecotoxicity data 

outlined on page 30 of this document. 

 The Agency has not conducted a risk assessment that supports a complete endangered 

species determination. The ecological risk assessment planned during registration review will 

allow the Agency to determine whether Irgarol 1051’s use has “no effect or “may affect” 

federally listed threatened or endangered species (listed species) or their designed critical 

habitats. When an assessment concludes that a pesticide’s use “may affect” a listed species or its 

designated critical habitat, the Agency will consult with the U.S. Fish and Wildlife Service 

and/or National Marine Fisheries Services (the Services), as appropriate.
Page 30 of 48

Environmental Fate and Ecotoxicity Data Gaps and Anticipated Work 

Environmental fate and ecological risk assessments have not been conducted for Irgarol 

1051. Irgarol 1051 is intended for use in formulating non-aquatic, non-crop use aqueous and 

solvent coating systems including paints, coatings, stucco, stains, and caulks for outdoor uses to 

inhibit or control the growth of algae on the coating surfaces. The Agency needs to conduct 

environmental fate and ecological risk assessments for outdoor uses of material preservatives 

[(to inhibit or control the growth of algae on the coating surfaces (such as exterior paints, 

coatings, stains, building materials such as vinyl roofing, elastomeric roof and wall coatings and 

mastics, caulks, sealants, joint cements, spackling, stucco, and grouting)] that potentially pass 

through waste water treatment plants (WWTPs) and may be discharged into terrestrial and 

aquatic environments. Therefore, the Agency anticipates needing the proposed environmental 

fate and ecotoxicity data for Irgarol 1051 and/or any of its major degradation products that are of 

potential concern for registered outdoor material preservative uses of Irgarol 1051. Also, the 

Agency needs to conduct an ecological risk assessment for Irgarol 1051 used in wood 

preservatives and antifouling coatings. The following environmental fate and ecotoxicity data 

are needed to conduct an environmental fate and ecological risk assessment: 

• The Agency anticipates needing the following data in order to conduct a complete 

environmental fate and ecological risk assessment, including an endangered species 

assessment for antifoulant coatings use pattern of Irgarol 1051: 

Anticipated Ecological Effects Data Needs: 

(GLN 850.1045) Acute Penaeid; 

(GLN 850.4225) Seedling emergence - dose response using rice (Oryza sativa); 

(GLN 850.4250) Vegetative vigor - dose response using rice (Oryza sativa); 

(GLN 850.1500) Fish (freshwater and/or estuarine/marine species) life cycle study; 

(GLN 850.1710) Oyster BCF; 

(GLN 850.1850) Aquatic organism bioavailability/biomagnifications, toxicity tests; 

(GLN 850.2300) Avian reproductive studies with bobwhite quail and/or mallard duck 

(GLN 850.4300) Terrestrial Plants Field Study; 

(GLN 850.4450) Aquatic Plants Field Study; and 

(GLN None) (Special study) Whole sediment - chronic invertebrates (freshwater 

and/or estuarine/marine) 

Anticipated Environmental Fate Data Needs: 

(GLN 850.6800) modified activated sludge respiration inhibition; 

(GLN 835.1110) activated sludge sorption isotherm; 

(GLN 835.3110) ready biodegradability; 

(GLN 835.6200) Aquatic (sediment) Field Dissipation; 

(GLN None) (Special study) Leachability of Irgarol 1051 used in coating 

systems for outdoor materials such as vinyl roofing, elastomeric roof and 

wall coatings; and mastics, caulks, sealants, joint cements, spackling, 

stucco, and grouting. A special leaching study is anticipated as being 
Page 31 of 48

 

needed which would be conducted with various typical end-use products 

that have been treated with Irgarol 1051. 

(GLN None) (Special study) Monitoring of representative U. S. waters (residue of 

 concern). 

Anticipated Ecological Effects and Environmental Fate Data Requirements for Outdoor 

Wood Preservative Uses of Irgarol 1051 

 Irgarol 1051 is listed as a biocide for use in manufacturing wood preservatives. For

Igrarol 1051 registered for treatment of wood products used in outdoor scenarios (e.g., decks, 

decking materials, aquatic uses), the Agency anticipates requiring the following data in order to 

conduct the environmental fate and ecological risk assessments, including an endangered species 

assessment. However, note that expected data needs may depend on factors such as the 

quantities of Irgarol 1051 (and/or major degradates or metabolites) leaching from wood (e.g., 

parent compound, major degradates or metabolites); the outdoor use scenarios in which Irgarol 

1051 treated wood may be used; and the Agency's evaluation of the leaching data along with the 

available use, effects, and exposure information for Irgarol 1051: 

Ecological Effects and Environmental Fate Studies:

1

 For use in this registration review, the following ecological effects and environmental 

fate data are anticipated as being needed: 

Anticipated Ecological Effects Data Needs: 

(GLN 850.4225) Seedling emergence - dose response using rice (Oryza sativa); 

(GLN 850.4250) Vegetative vigor - dose response using rice (Oryza sativa); 

(GLN 850.1045) Acute Penaeid; 

(GLN 850.1500) Fish (freshwater and/or estuarine/marine species) life cycle study; 

(GLN 850.1710) Oyster BCF; 

(GLN 850.1850) Aquatic organism bioavailability/biomagnifications, toxicity tests; 

(GLN 850.2300) Avian reproductive studies with bobwhite quail and/or mallard duck; 

(GLN 850.3020) Honeybee acute contact LD50; 

(GLN 850.3030) Toxicity of residues to honeybees, “Honey Bee Toxicity of Residues on 

Foliage”; 

(GLN 850.4300) Terrestrial Plants Field Study; 

(GLN 850.4450) Aquatic Plants Field Study; and 

(GLN None) (Special study) Whole sediment - chronic invertebrates (freshwater and/or 

estuarine/marine) 

Anticipated Environmental Fate Data Needs: 

(GLN 835.2410) Photodegradation in soil; 

(GLN 835.4200) Anaerobic soil metabolism; 

1

 Test material for anticipated studies would depend in part on what chemicals are leaching from Irgarol 1051-

treated wood. 
Page 32 of 48

(GLN 835.6200) Aquatic (sediment) Field Dissipation; 

(GLN None) (Special study) Leachability of Wood Preservatives (AWPA E11-06); 

(GLN None) (Special study) Soil leaching from wood study (AWPA E20-04); and 

(GLN None) (Special study) Monitoring of representative U. S. waters (residue of concern). 
Page 33 of 48 

APPENDICES 
Page 34 of 48 

Appendix A. Environmental Fate Guideline Study Justificat

Guideline Study Title Practical Utility of the Data 850.6800 Modified 

Activated Sludge, Respiration Inhibition 

1) What is the value of the study? The modified activated sludge, respiration inhibition test would allow EPA to identify which could harm microorganisms found in biological wastewater treatment systems anestablish correct concentrations for use in the ready biodegradability test. 2) How would the data be used? The data would be used to determine the potential of Irgarol 1051 to directly harm the n

and/or to microbial treatment processes present in a WWTP and to determine suitable nconcentrations of Irgarol 1051 to be used in biodegradability tests. 3) How could the data affect the risk assessment? If the data shows that Irgarol 1051 is toxic to nontarget organisms and/or to microbial pthen, the Agency may need Tier II environmental fate data to evaluate potential adverse 4) What is triggering the need for this data? Studies are needed to conduct environmental fate assessment and to determine the pote

1051 to waste water treatment plants (WWTPs) (via effects on WWTP microbes).

835.1110 Activated Sludge 

Sorption Isotherm 

1) What is the value of the study? The results from activated sludge sorption study would allow EPA to assess the distribuamong the solid, aqueous, and vapor phases of WWTPs. Specifically, this study identi

which sorb to sludge biomass. 2) How would the data be used? The data would be used to determine the sorption potential of Irgarol 1051 to activated biological wastewater treatment systems. 3) How could the data affect the risk assessment? If Irgarol 1051 is not sorbed or biodegraded then, it would pass through a biological treunaffected and it may contaminate surface and drinking waters and also may have pote
Page 35 of 48 

Appendix A. Environmental Fate Guideline Study Justificat

Guideline Study Title Practical Utility of the Data 

nontarget organisms. 4) What is triggering the need for this data? Studies are needed to conduct environmental fate assessment and to determine the sorpactivated sludge for the removal of specific chemical compounds in biological wastewa

835.3110 Ready 

Biodegradability 

1) What is the value of the study? The ready biodegradability study would enable the Agency to determine the likelihood pesticide of biodegrading in aquatic environments under aerobic conditions. 

2) How would the data be used? The results from the data would be used to determine the rate and extent of aerobic bio1051 when it is released into aquatic environments and would help establish if Irgarol 1stable under real environmental conditions. 3) How could the data affect the risk assessment? If the result shows low biodegradability then, Irgarol 1051 would occur in significant qeffluents (water and biosolids) and in environmental compartments (e.g., surface water

adverse effects to nontarget organisms, found in such environmental compartments, ma4) What is triggering the need for this data? Data are needed to conduct environmental fate assessment and to determine the ready bIrgarol 1051.

835.2410 Photodegradation 

in soil 

1) What is the value of the study? Pesticides are applied to the surface of soil and/or on the exposed surfaces of plants, are 

photodegradation. This study will provide data on photolytic pesticide dissipation and persistence of photoproducts formed by soil surface catalyzed photolysis. Biocides introduced into the surface of soil in the environment can undergo photolytic 

sunlight. Results from the soil photolysis study will indicate the stability and persisten

potential degradates in the soil environment when exposed to sunlight. For outdoor woIrgarol 1051 can reach surface soil through direct contact or discharge to WWTPs. Irg
Page 36 of 48 

Appendix A. Environmental Fate Guideline Study Justificat

Guideline Study Title Practical Utility of the Data 

surface soil or groundwater through run-off or leaching processes. The Agency will ev

of concern. 2) How would the data be used? The data would establish the significance of chemical photolysis as a route for degradapossible, the photolytic degradation products formed that may adversely affect non-targcontaminate water and food source of aquatic organisms. The data would also help esthalf-life of Irgarol 1051 and possibly degradates, and assist in developing a degradation 3) How could the data affect the risk assessment? The results of photolysis data would indicate if Irgarol 1051 is persistent or if it degradproducts that may adversely affect nontarget organisms and may contaminate their foodthe photodegradation in soil study for wood preservatives. Leaching of wood preservattransformation products) from preservative-treated wood could contaminate the surrounprovide data on the dissipation, nature and persistence of wood preservative degradatio

soil surface catalyzed photolysis. Using these data the Agency can assess the extent and (e.g., children playing below decks) and/or nontarget organism exposures to soils adjactreated wood structures. Such soils may contain the parent compound and/or transformcould include those formed via photodegradation processes. 4) What is triggering the need for this data? Soil photodegradation data is needed to conduct the fate assessment to support indoor apreservative uses for Irgarol 1051. 

835.4200 Anaerobic soil 

metabolism 

1) What is the value of the study? The purpose of an anaerobic soil metabolism study is to determine the nature and extendegradation under anaerobic conditions in soil, and characterize the formation and declinformation is used to ascertain effects of flooding or water logging on a well-aerated shave an effect on many oxidation-reduction systems and, in turn, may indirectly affect fate. This information will determine the persistence and concentrations of Irgarol 105degradates over time in representative soils. The Agency will evaluate the potential ris
Page 37 of 48 

Appendix A. Environmental Fate Guideline Study Justificat

Guideline Study Title Practical Utility of the Data 

2) How would the data be used? The data would establish the significance of anaerobic microbial degradation of Irgarol degradation and identify, if possible, the degradation products formed that may adverseorganisms and may contaminate water and food sources of aquatic organisms. The dat

establish the anaerobic microbial half-life of Irgarol 1051 in soil, and possibly it’s degrdeveloping a degradation pathway. 3) How could the data affect the risk assessment? The results would indicate the nature and extent of formation and decline under anaero

1051 and its degradates to which rotational crops and nontarget organisms will be expoassessment of potential disposal problems. The study helps to determine the degradatioIrgarol 1051 in the presence of microorganisms in different natural soils and determineformed under anaerobic (oxygen-poor) conditions in the laboratory.4) What is triggering the need for this data? Anaerobic soil metabolism data is needed to conduct the fate assessment to support indpreservative uses for Irgarol 1051.

835.6200 Aquatic field 

dissipation study 

1) What is the value of the study? The purpose of an aquatic field dissipation study for biocides for aquatic uses is to deteextent of dissipation and mobility of the biocide and its residues under actual use condistudies will generate on-site data for evaluating potential hazards of a biocide under actmobility, formation of metabolites, and disappearance of parent compound) and provid

respect to mechanisms of dissipation in various aquatic environments. An aquatic field required because biocide dissipation may proceed at a different rate in the aquatic envirlaboratory aquatic studies. The results will indicate the potential for Irgarol 1051 to coenvironment that may come in contact with the effluent discharge since biocide residueirrigated crops and passed on to other parts of the aquatic food web. The Agency will erisks of concern.2) How would the data be used? The data would establish the significance of aquatic microbial degradation along with m
Page 38 of 48 

Appendix A. Environmental Fate Guideline Study Justificat

Guideline Study Title Practical Utility of the Data 

as a route for dissipation under actual use conditions and identify, if possible, the degrathat may adversely affect non-target organisms and may contaminate water and food soorganisms. The data would also help establish the aerobic aquatic microbial half-life ofield systems, and possibly it’s degradates, and assist in developing a degradation pathw3) How could the data affect the risk assessment? The results would indicate the nature and extent of leaching and persistence of Irgarol in an aquatic field system under actual use conditions. The results would also facilitate disposal problems. The study helps to determine the degradation rate (half-life) of Irgafield system under actual use conditions. 4) What is triggering the need for this data? Aquatic field study data is needed to conduct the fate assessment to support slimicide uindustrial cooling tower water systems for Irgarol 1051. Also data are needed in order t

risk assessment for antifoulant coatings, outdoor wood preservative, and aquatic areas u1051.

AWPA 

E11-06 

Leachability of Wood Preservatives 

1) What is the value of the study? The results from the wood preservative leaching study would allow measurement of the 

1051 from treated wood windows, doors, and engineered components used in constructdecay resistance is necessary. The purpose is to provide information on relative permapreservatives. The method is designed for waterborne preservatives and may not be ap

preservatives. For outdoor wood preservative uses, Irgarol 1051 can reach surface wator discharge to WWTPs. Irgarol 1051 can also reach surface water or groundwater thro

processes. The Agency will evaluate the potential risks of concern. 2) How would the data be used? The data would be used to determine the leachability of wood preservatives expressed original preservative retention. The amount of preservative leached is expressed as the contained in the leachate to the total preservative present. 3) How could the data affect the risk assessment? 
Page 39 of 48 

Appendix A. Environmental Fate Guideline Study Justificat

Guideline Study Title Practical Utility of the Data 

If Irgarol 1051 is leached from the wood in large percentage, then it may contaminate swaters and also have potential adverse effects to nontarget organisms and the aquatic e4) What is triggering the need for this data? For wood preservatives, an aquatic leaching study is required. This study is also needed ecological effects assessment, to determine the leachability of wood preservatives expr

the original preservative retention and to confirm that ion levels in the leachate would bconcern. 

AWPA 

E20-06 

Leachability of Wood Preservatives in Soil Contact 

1) What is the value of the study? The results from the wood preservative leaching study would allow measurement of the 

1051 from treated wood resulting from physical/chemical reactions during exposure to to provide information on the relative permanency of wood preservatives designed for be exposed to soil contact. The results are based on the moisture content of the treated from the soil and the amount of biocide(s) loss from the treated wood for each specimenon-aquatic wood preservative uses (i.e., decks and decking material), the wood will be the soil. Irgarol 1051 can reach surface water through direct contact or discharge to Walso reach surface water or groundwater through run-off or leaching processes. The Agpotential risks of concern. 2) How would the data be used? The data would be used to determine the leachability of wood preservatives expressed original preservative retention. The amount of preservative leached is expressed as the contained in the leachate to the total preservative present. 3) How could the data affect the risk assessment? If Irgarol 1051 is leached from the wood in large percentage then, it may contaminate swaters and also may have potential adverse effects to nontarget organisms and the aqua4) What is triggering the need for this data? For wood preservatives, a soil leaching study is required if human or environmental ex

occur from leachates that contain the active ingredient or principal transformation prod
Page 40 of 48 

Appendix A. Environmental Fate Guideline Study Justificat

Guideline Study Title Practical Utility of the Data 

with a preservative product. Leachability of wood preservatives in soil contact data is nfate assessment to support indoor and outdoor wood preservative uses for Irgarol 1051. needed to conduct the ecological effects assessment, to determine the leachability of wexpressed as a percentage of the original preservative retention and to confirm that ion would be of no toxicological concern. 

(GLN None) Monitoring of 

representative U. S. waters (residue of concern) 

Monitoring of representative U. S. waters is required because environmental fate study indicate that the active ingredient and principal transformation products are likely to oc

freshwater, estuarine, or marine waters such that human or environmental exposures ar
Page 41 of 48 

Appendix B: Ecological Guideline Study Justifications 

Guideline Study Title Practical Utility of the Data: Aquatic Organism Testing 850.1035 

or 

850.1045 

Acute LC50 with an 

estuarine/marine shrimp species 

1) What is the value of the study?

Shrimp are important economic species to the United States as are lobsters, crabs, Shrimp are used as surrogate for all other crustaceans. These acute toxicity tests mestuarine/marine shrimp species, including mysids (OPPTS 850-1035) and penaeiacross a range of concentrations to determine if survival is inhibited by short-term Irgarol 1051 in estuarine/marine waters. 

2) How would the data be used?

Data would be used to describe the concentration-response curves and determine 4

(concentrations calculated to kill 50% of the population) along with 95% confiden

3) How could the data affect the risk assessment?

Mysidopsis bahia is considered as a surrogate species to represent all estuarine/ma

risk assessment process. As part of the acute risk assessment for aquatic animals, 

for estuarine/marine invertebrates is used in the RQ method for expressing risk. Aindicate an acute LOC, defined as the potential for acute risk to non-target aquatic warrant regulatory action in addition to restricted use classification. An acute RQ acute restricted use LOC, defined as the potential for acute risk to non-target organmitigated through restricted use classification. An acute RQ > 0.05 would fall undendangered species. 

4) What is triggering the need for this data? 

Data are needed in order to conduct an ecological risk assessment for the use of Irantifoulant coating, and outdoor wood preservative and determine the acute toxiciestuarine/marine shrimp.

850.1500 Fish (freshwater 

and/or estuarine/ marine species) life 

1) What is the value of the study? 

This study allows the Agency to determine if a pesticide is toxic to fish offspring, 

and ultimate survival. The fish life cycle toxicity study is required: if the estimate
Page 42 of 48 

Appendix B: Ecological Guideline Study Justifications 

Guideline Study Title Practical Utility of the Data: 

cycle study concentration is equal to or greater than one-tenth of the NOAEC in the fish early 

life-cycle tests; or if studies of other organisms indicate that the reproductive physaffected. Fish are exposed to the pesticide from one stage of the life cycle to at leanext generation (e.g., egg to egg), This duration allows examination not only of e

also on reproduction (spawning, egg numbers, fertility, and fecundity), locomotion

and pathology. 

2) How would the data be used? 

Data would be used to establish an LC50 for mortality and EC50s for selected suble

parameters, in addition to NOAECs. Sublethal parameters include embryo hatch rgrowth (length), exposed adult egg production, second generation hatch rate, and s

growth. 

3) How could the data affect the risk assessment? 

As part of the chronic risk assessment for aquatic animals, the lowest NOAEC for used as inputs to the RQ equation. A chronic LOC is defined by an RQ > 1, and wis the potential for chronic risk that may warrant regulatory action and that endangpotentially be affected through chronic exposure. 

4) What is triggering the need for this data? 

Data are needed in order to conduct an ecological risk assessment for the use of Irantifoulant coating, and outdoor wood preservative and determine the chronic toxifreshwater and marine fish using life-cycle studies.

850.1710 850.1730 850.1850 

Aquatic organism bioconcentration/ biomagnification/ toxicity tests 

1) What is the value of the study?

The value of these studies is that freshwater and/or marine aquatic species of invercan be examined to determine if a pesticide has the potential to accumulate in bodbioconcentration from the water and/or indirectly through biomagnification via fochain. 

2) How would the data be used?

In the oyster (850.1710) and fish (850.1730) BCF tests, parameters include mortal
Page 43 of 48 

Appendix B: Ecological Guideline Study Justifications 

Guideline Study Title Practical Utility of the Data: 

steady-state or maximum bioconcentration factors (BCF) and uptake and depuratioAdditionally, the major degradates can be identified and quantified at steady statechain transfer study (850.1850), a hierarchy of organisms at different trophic levelbiomagnification. Typically, the categories include insect nymphs, crustaceans, m(bottom-feeding, cold-water, and warm-water or marine). 

3) How could the data affect the risk assessment? 

In the risk assessment process, direct effects LOCs for each taxonomic group are uconcerning the potential for indirect effects upon listed species that rely upon non-Information on the bioconcentration from water and biomagnification via the food assessors in making the inferences about indirect effects. 

4) What is triggering the need for this data? 

Data are needed in order to conduct an ecological risk assessment for the use of Irantifoulant coating, and outdoor wood preservative and determine any potential biwater or biomagnification via food transfer.

Sediment Testing None Whole sediment - 

chronic invertebrates (freshwater and/or estuarine/marine) 

1) What is the value of the study? 

Some pesticides tend to build up in sediments over time. Some pesticides are relewater and some are bound to sediments. The value in these non-guideline chronic provide longer-term toxicity data than the acute whole sediment freshwater and es

invertebrate studies. These studies use natural sediment spiked with different con

chemical to determine the toxicity and bioaccumulation potential of chemicals in s

and estuarine/marine invertebrates. Whole sediment toxicity tests may include the Hyalella azteca, and the midge, Chironomus tentans, for freshwater tests and the eamphipods, Ampelisca abdita, Eohaustorius estuarius, Rhepoxynius abronius, and plumulosus for salt water tests. 

2) How would the data be used?

Reported endpoints from whole sediment chronic toxicity tests may include the LC

the LOAEC. Results from the sediment toxicity tests can be used to determine cau
Page 44 of 48 

Appendix B: Ecological Guideline Study Justifications 

Guideline Study Title Practical Utility of the Data: 

between the chemical and biological responses within the sediment and the organi

3) How could the data affect the risk assessment? 

While other studies address the aquatic toxicity and/or bioconcentration of inverte

column, this whole sediment acute toxicity test can provide valuable information o1051 to freshwater invertebrates in and/or on the sediment. In addition to the interwater, these invertebrates are exposed via the sediment pore water, for which the wsignificantly different. Furthermore, freshwater amphipods and midges and estuarserve important ecological roles as food sources for vertebrates and larger inverteb

4) What is triggering the need for this data? 

Sediment testing with estuarine/marine test species is required because the log Kothe Koc is equal to or greater than 1,000. These values indicate that there is a h

Irgarol 1051 to preferentially partition to aquatic sediment. Data are needed 

ecological risk assessment for the use of Irgarol 1051 as an antifoulant coating and preservative and determine chronic toxicity and bioaccumulation potential of chemfreshwater and estuarine/marine invertebrates. 

Avian Testing 850.2300 Avian reproductive 

studies with bobwhite quail and/or mallard duck 

1) What is the value of the study?

Birds eat certain insects and plants, wade in contaminated water, and ingest residu

time, the residues build up to toxic levels. The value of this study is that it providereproductive effects of Irgarol 1051 via dietary exposure on the bobwhite and malthree phases. In the initial phase, hens are fed the test diets for 6 to 8 weeks. Duri

photoperiod is manipulated to bring the hens into laying condition, and this phase 

egg-laying. The final phase comprises 8-10 weeks of egg-laying. 

2) How would the data be used? 

Results of this study will be used to measure any possible reproductive risks to birIrgarol 1051 by examining the numbers of eggs laid, eggs cracked, viable embryoalive at 18 days, and chicks surviving to 14 days. Additionally, hatchability and ereported. 
Page 45 of 48 

Appendix B: Ecological Guideline Study Justifications 

Guideline Study Title Practical Utility of the Data: 

3) How could the data affect the risk assessment? 

These bird species act as surrogate species for reptiles and terrestrial-phase amphiother birds in the risk assessment process. There are many avian, reptile, and amplisted as threatened and endangered in the United States. Amphibian declines, in pconcern. As part of the chronic risk assessment for terrestrial animals, the lowest toxicity is used in the RQ equation. A chronic LOC is defined by an RQ > 1, and is the potential for chronic risk that may warrant regulatory action and that endang

potentially be affected through chronic exposure. 

4) What is triggering the need for this data? 

Data are needed in order to conduct an ecological risk assessment for the use of Irantifoulant coating and outdoor wood preservative and determine the effects of Irgreproduction.

Insect Pollinator Testing 850.3020 850.3030 

Honeybee acute contact LD50

Honey Bee Toxicity of Residues on Foliage (Toxicity of residues to honeybees) 

1) What is the value of the study?

Pesticide treated wood is sometimes used to make bee hives resulting in bee exposresidues. The honey bee acute contact toxicity test provides data on the acute toxiexposure via microapplicator or dusting) followed by a 48-h observation period. 

2) How would the data be used? 

Results of this study will be used to assess risks to honeybees (nontarget insects) f1051. Mortality, signs of intoxication, and other abnormal behavior (e.g., ataxia, lhypersensitivity) are reported. The LD50 with 95% confidence interval is calculate

response curve data. 

3) How could the data affect the risk assessment? 

Data are needed for future regulatory decisions and for an endangered species asseThere are many terrestrial invertebrates that are listed as threatened and endangerethe Agency better characterize the potential risk to insects (including beneficial poof Irgarol 1051. 
Page 46 of 48 

Appendix B: Ecological Guideline Study Justifications 

Guideline Study Title Practical Utility of the Data: 

4) What is triggering the need for this data? 

This study has been added to the battery of studies that EPA requires to support ouhoneybees are likely to be exposed to pesticides. The proposed use of Irgarol 105use as a wood preservative would likely allow bees to be exposed to the pesticide. 

Plant Testing 850.4225 Seedling emergence, 

Tier II - dose response using rice (Oryza sativa) 

1) What is the value of the study? 

Plants prevent erosion and provide animals with food and shelter. The rooted aqurepresent exposure to all vascular rooted plants. Tier II (Definitive Studies) tests a

determination that a greater than 25% adverse effect occurred in the Tier I (Initial seedling emergence study for one or more plant species. These Tier II terrestrial nphytotoxicity tests evaluate the acute toxicity of pesticides to 10 crop plant speciesand four Monocots. Although rice (Oryza sativa) is not one of the surrogate terrestypically tested, its semiaquatic environment is applicable to run-off scenarios. If 

TSCA, the test material is applied daily with each watering for the duration of the carried out for at least 14 days after seedling emergence. 

2) How would the data be used? 

Along with vegetative vigor studies, results of these studies will be used to assess 

exposure to terrestrial, semiaquatic, and aquatic nontarget plants. Parameters of ppercent emergence, number of emerged plants, seedling height, seedling dry weighweight, and signs of phytotoxicity. Results are reported as EC05 (NOAEC), EC25, 

3) How could the data affect the risk assessment?

Because Irgarol 1051 would not be directly applied to the field, information on entransport would affect the risk identification and characterization to non-target plaNontarget plants include plants outside the area of intended application (which wofood and cover vegetation for animals, food, fiber, fuel, and ornamental plants for endangered and threatened plants). Terrestrial plants serve as food and shelter for control erosion, and serve as air pollution filters. Shoreline vegetation buffers redan environment in which aquatic invertebrates can contribute to the food supply oamphibians. Vegetation adjacent to streams serves to regulate water temperature, 
Page 47 of 48 

Appendix B: Ecological Guideline Study Justifications 

Guideline Study Title Practical Utility of the Data: 

contributes to improved aquatic life. Decaying vegetation provides nutrients essenchain. Hedgerows, woodlots, and other similar nontarget areas provide food and cavian species. There are many terrestrial plants that may be affected where Irgarol 1051 is used aand outdoor wood preservative. If EPA is unable to evaluate the potential risks to associated with the new use of Irgarol 1051, these risks must be presumed. As parfor terrestrial plants (non-endangered and endangered), the lowest EC25 for monoc

the RQ equation. The LOC for endangered and non-endangered plants is defined 

4) What is triggering the need for this data? 

Data are needed in order to conduct an ecological risk assessment for the use of Irantifoulant coating and outdoor wood preservative and determine the effects of Irgemergence.

850.4250 Vegetative vigor, 

Tier II - dose response using rice (Oryza sativa) 

1) What is the value of the study?

Plants prevent erosion and provide animals with food and shelter. The rooted aqu

represent exposure to all vascular rooted plants. Tier II (Definitive Studies) tests adetermination that a greater than 25% adverse effect occurred in the Tier I (Initial 

vegetative vigor study for one or more plant species. These Tier II terrestrial nonttests evaluate the acute toxicity of pesticides to 10 crop plant species, including six Monocots. Although rice (Oryza sativa) is not one of the surrogate terrestrial crop 

its semiaquatic environment is applicable to both leaching and run-off scenarios. 

applied 2 to 4 weeks after the plants have emerged from the soil, and observations least 14 days. 

2) How would the data be used?

Along with the seedling emergence studies, results of these studies will be used to 

and aquatic plants from exposure to Irgarol 1051. Parameters of plant growth incldry weight, root length, root dry weight, and signs of phytotoxicity. Results are re

(NOAEC), EC25, and EC50. 
Page 48 of 48 

Appendix B: Ecological Guideline Study Justifications 

Guideline Study Title Practical Utility of the Data: 

3) How could the data affect the risk assessment?

Because Irgarol 1051 would not be directly applied to the field, information on entransport would affect the risk identification and characterization to non-target platerrestrial plants that are listed as threatened and endangered in the United States wused as an antifoulant coating and outdoor wood preservative. If EPA is unable to risks associated with the antifoulant coating and outdoor wood preservative uses orisks must be presumed. As part of the risk assessment for terrestrial plants (non-eendangered), the lowest EC25 for monocots and dicots is used in the RQ equation. 

endangered and non-endangered plants is defined as a RQ > 1. 

4) What is triggering the need for this data? 

Data are needed in order to conduct an ecological risk assessment for the use of Irantifoulant coating and outdoor wood preservative and determine the effects of Irgvigor.