BIOPESTICIDES REGISTRATION 

ACTION DOCUMENT 

 

Phoma macrostoma strain 94-44B

DRAFT DOCUMENT 

U.S. ENVIRONMENTAL PROTECTION AGENCY

OFFICE OF PESTICIDE PROGRAMS

BIOPESTICIDES AND POLLUTION PREVENTION DIVISION

November 30, 2011 
TABLE OF CONTENTS

ACRONYMS ...................................................................................................................................................... 4

EXECUTIVE SUMMARY ..................................................................................................................................... 7

I. REGULATORY BACKGROUND .................................................................................................................... 8

A. Application for Pesticide Registration ..................................................................................................... 8 

B. North American Free Trade Agreement Joint Review............................................................................. 8 

C. Public Participation .................................................................................................................................. 8 

II. BIOLOGICAL CONSIDERATIONS ................................................................................................................ 9

III. ACTIVE INGREDIENT CHARACTERIZATION ................................................................................................ 10

A. Product Chemistry and Composition .................................................................................................... 10 

1. Product Identity .............................................................................................................................. 10 

2. Manufacturing Process ................................................................................................................... 10 

3. Deposition of a Sample in a Nationally Recognized Culture Collection .......................................... 11 

4. Discussion of Unintentional Ingredients ......................................................................................... 11 

B. Analysis and Certified Limits.................................................................................................................. 11 

1. Analysis of Samples ......................................................................................................................... 11 

2. Certification of Limits ...................................................................................................................... 11 

C. Physical and Chemical Properties .......................................................................................................... 11 

IV. HUMAN HEALTH RISK ASSESSMENT ...................................................................................................... 12

A. Toxicity .................................................................................................................................................. 12 

1. Acute Toxicity .................................................................................................................................. 12 

2. Endocrine Effects ............................................................................................................................ 13 

B. Exposure ................................................................................................................................................ 14 

1. Occupational Exposure ................................................................................................................... 14 

2. Residential, School, and Day Care Exposure ................................................................................... 15 

C. Human Health Risk Characterization ..................................................................................................... 15 

V. ECOLOGICAL RISK ASSESSMENT AND ENDANGERED SPECIES ASSESSMENT ....................................................... 15

A. Ecological Risk Assessment ................................................................................................................... 15 

1. Effects of Phoma macrostoma strain 94-44B to Nontarget Organisms (Ecotoxicity) ..................... 16 

2. Environmental Fate ......................................................................................................................... 17 

3. Environmental Risk Characterization .............................................................................................. 17 

B. Threatened and Endangered Species Assessment ................................................................................ 18 

1. Direct Effects ................................................................................................................................... 18 

2. Indirect Effects and Effects to Critical Habitat ................................................................................ 18 

VI. RISK MANAGEMENT .......................................................................................................................... 19

A. Risk Mitigation ....................................................................................................................................... 19 

1. General ............................................................................................................................................ 19 

2. Environmental ................................................................................................................................. 19 

B. Future Changes to the Use Pattern ....................................................................................................... 19 

VII. REGISTRATION ELIGIBILITY DETERMINATION ........................................................................................... 19

A. Decision ................................................................................................................................................. 19 

B. Terms of the Registration ...................................................................................................................... 20 

VIII. ENVIRONMENTAL JUSTICE ................................................................................................................. 20

BIBLIOGRAPHY ............................................................................................................................................... 21
-3-

BRAD TEAM

Office of Pesticide Programs 

Biopesticides and Pollution Prevention Division 

Microbial Pesticides Branch 

Science Review 

Joel Gagliardi, Ph.D. Product Analysis and Human Health Risk 

Shannon Borges, M.S. Environmental and Ecological Risk 

Gail Tomimatsu, Ph.D. Secondary Review of Environmental and Ecological Risk 

Regulatory 

Kathleen Martin, M.S.E.S. Regulatory Action Leader

Sheryl Reilly, Ph.D. Chief, Microbial Pesticides Branch

 
-4-

ACRONYMS

♀ Female 

♂ Male 

a.i. Active Ingredient 

AAFC Agriculture and Agri-Food Canada 

AFLP Amplified Fragment Length 

Polymorphism 

APHIS USDA’s Animal and Plant Health 

 Inspection Service 

ASTM American Society for Testing and 

Materials 

bw Body Weight 

CD® A strain of laboratory rat from Charles 

 River; it originated from work by 

 Robert Dawley. 

CFR Code of Federal Regulations 

CFU Colony Forming Unit 

CFU/g CFUs per gram 

CFU/kg CFU per kg of body weight per day 

bw day 

CFU/mL CFUs per milliliter 

cm centimeter 

cm2

 Centimeters squared; a measure 

 of surface area. 

DNA Deoxyribonucleic acid 

EC50 Effective concentration 

EDSP Endocrine Disruptor Screening 

Program 

EPA U.S. Environmental Protection Agency 

 or, the Agency 

FFDCA Federal Food, Drug, and Cosmetic Act 

FIFRA Federal Insecticide, Fungicide, and 

 Rodenticide Act 

FR Federal Register

FWS The U.S. Fish and Wildlife Service 

g gram

GPO Government Printing Office 

i.p. Intraperitoneal 

IDAC The International Depositary 

 Authority of Canada 

ITS Internal Transcribed Spacer 

kg kilogram 

LC50 Median Lethal Concentration 

LD50 Median Lethal Dose 

mg milligram 

mph miles per hour 

MRID Master Record IDentification (number) 

NA Not Applicable 

NAFTA North American Free Trade Agreement 

NOAEC No-observed-adverse-effectconcentration 

NOR Notice of Receipt 

OPP EPA’s Office of Pesticide Programs 

P. Phoma macrostoma

macrostoma 

PC Code Pesticide Chemical Code: a six-digit 

 number assigned by OPP to identify 

 pesticide chemicals. 

PCR Polymerase Chain Reaction 

PFGE Pulsed Field Gel Electrophoresis 

PMRA Health Canada’s Pest Management 

 Regulatory Agency 

PPE Personal Protective Equipment 

PPQ Plant Protection and Quarantine 

RAPD Random Amplification of Polymorphic 

DNA 

rDNA Ribosomal DNA 

TGAI Technical grade active ingredient 

U.S. United States 

USDA U.S. Department of Agriculture 

WPS Worker Protection Standard 

 
P. macrostoma strain 94-44B page 7 

Biopesticides Registration Action Document 

DRAFT DOCUMENT 

EXECUTIVE SUMMARY 

Phoma macrostoma strain 94-44B is a newly developed bioherbicide that will be used to 

control pre- and post-emergent broadleaf weeds such as dandelion on ornamental plants and 

turf. Phoma macrostoma is a fungus; strain 94-44B was found along a roadway in 

Saskatchewan, Canada, on diseased Canada thistle. 

 In 2010, the Scotts Company applied to Health Canada’s Pest Management Regulatory 

Agency (PMRA) and the U.S. Environmental Protection Agency’s (EPA) Office of Pesticide 

Programs for registration of products containing this new active ingredient. Under the purview 

of the North American Free Trade Agreement, Scotts requested that the review be conducted 

jointly between the two countries. In November 2011, PMRA conditionally registered five 

products containing P. macrostoma strain 94-44B. A summary of their Evaluation Report 

(document number ERC2011-09) can be found at: www.hc-sc.gc.ca/cpsspc/pubs/pest/_decisions/erc2011-09/index-eng.php. EPA intends to register three products 

containing P. macrostoma strain 94-44B as the active ingredient—one manufacturing- and 

two-end products. 

 Human Health. EPA has determined that use of this new bioherbicide will not cause 

unreasonable adverse effects to human health or the environment. The acute toxicity of 

P. macrostoma strain 94-44B is low. In acute toxicity testing, P. macrostoma strain 94-44B 

was not toxic via any route. The Acute Toxicity Category for oral, inhalation, and dermal 

exposure is IV (see 40 CFR 156.62 for a description of the Categories). P. macrostoma strain 

94-44B is slightly irritating to the eyes (Toxicity Category III) and is not a skin irritant (Toxicity 

Category IV). 

 Environment. EPA does not expect adverse effects to birds; wild mammals; insects; 

honey bees; freshwater fish and invertebrates; marine/estuarine fish and invertebrates; and 

aquatic plants. Effects to nontarget plants beyond the treated sites are expected to be limited 

to immediately adjacent areas for applications to turf and ornamentals, and effects will be 

limited to more highly susceptible species. Some species of nontarget plants may be 

adversely affected where significant exposure occurs; however, environmental fate data show 

that P. macrostoma strain 94-44B is unlikely to persist at high levels for long periods of time. 

 Threatened and Endangered Species. Under the Endangered Species Act of 1973, 

EPA has made a no effect determination for the use of pesticide products containing 

P. macrostoma strain 94-44B as an active ingredient. The U.S. Fish and Wildlife Service 

defines the term ‘no effect’ to mean that “its proposed action will not affect a listed species or 

designated critical habitat.” EPA’s no effect finding is based on the lack of adverse effects to 

terrestrial vertebrates, nontarget insects, and freshwater and marine/estuarine animals and 

plants. 
P. macrostoma strain 94-44B page 8 

Biopesticides Registration Action Document 

DRAFT DOCUMENT 

Phoma macrostoma strain 94-44B (PC Code 080303) is a fungus that has been developed as a 

bioherbicide to control pre- and post-emergent broadleaf weeds such as dandelion (AAFC 2009). The 

isolate P. macrostoma strain 94-44B was found in Saskatchewan, Canada, on diseased Canada thistle. 

In October 2009, the Scotts Company applied to the U.S. Environmental Protection Agency (EPA or the 

Agency) for registration of three products (one manufacturing- and two end-use) containing this new 

active ingredient (a.i.). Provided below is a summary of the products. 

Phoma Tech Phoma H Phoma P 

File Symbol 239–ETNE 239–ETNG 239–ETNU 

% a.i. 92% 92% 92% a

CFU/g 1 × 103 1 × 103 1 × 103

Proposed 

Uses 

Formulation of 

herbicides intended 

for terrestrial, 

nonfood uses. 

Residential, to control 

weeds in or around 

flower beds and roses, 

shrubs, trees, ornamental 

grasses, and turf. 

Commercial and agricultural, 

to control weeds in ornamental 

plants (flowers and roses, 

ground covers, shrubs, and 

trees), ornamental grasses, 

turfgrass (including seed 

starting applications), 

field-grown nursery 

plants, landscapes, and 

container plants. a

CFU=colony forming unit. 

I. REGULATORY BACKGROUND 

A. Application for Pesticide Registration. A Notice of Receipt (NOR), announcing EPA’s 

receipt of Scotts’ application to register pesticide products containing P. macrostoma strain 

94-44B, was published in the Federal Register on March 10, 2010 (75 FR 11175); no 

comments were received. This notice is available through the Government Printing Office’s 

(GPO) Federal Register web page: www.gpoaccess.gov/fr/retrieve.html (note: select the 

2010 radio button; the page number is 11176). 

B. North American Free Trade Agreement Joint Review. P. macrostoma strain 94-44B was 

the subject of a North American Free Trade Agreement (NAFTA) joint registration review 

conducted by EPA’s Office of Pesticide Programs (OPP) and Health Canada’s Pest 

Management Regulatory Agency (PMRA). PMRA has conditionally registered five products 

containing P. macrostoma strain 94-44B as the active ingredient. A summary of PMRA’s 

Evaluation Report (document number ERC2011-09) can be found at: www.hc-sc.gc.ca/cpsspc/pubs/pest/_decisions/erc2011-09/index-eng.php. 

C. Public Participation. On October 1, 2009, EPA announced a new policy to provide a more 

meaningful opportunity for the public to participate in major registration decisions before 

they occur. According to this new policy, the Agency provides a public comment period prior 

to making a registration decision for (at minimum): new active ingredients; first food uses; 

first outdoor uses; first residential uses; and any other registration decisions for which the 

Agency believes there may be substantial public interest. 

 Consistent with this new policy of making registration actions more transparent, P. 

macrostoma strain 94-44B is subject to a 30-day comment period as a ‘new active 

ingredient’ whose registration would result in ‘first outdoor uses’ and ‘first residential uses.’ 

The public comment period runs from December 1, 2011 to December 31, 2011. To submit 

a comment, see the instructions at EPA’s webpage titled, “Instructions for Commenting 

During Open Comment Periods” (www.epa.gov/pesticides/regulating/comment- 
P. macrostoma strain 94-44B page 9 

Biopesticides Registration Action Document 

DRAFT DOCUMENT 

instruction.html). The “Docket Folder Summary” for this action is accessed through 

regulations.gov; the docket number is EPA-HQ-OPP-2010-0094 (note: under “Enter 

Keyword or ID” enter the docket number). 

II. BIOLOGICAL CONSIDERATIONS (MRID 479150-01). Phoma macrostoma is a fungus of the 

class Coelomycetes. It is commonly isolated from woody plants and, is found incidentally on other 

plants, in soil, and leaf litter. In the United States, it has been isolated from plants (mainly trees). 

Countries where P. macrostoma is found include: 

▪ Africa (Egypt, Ethiopia, Kenya, Nigeria, Tanzania, and Zimbabwe); 

▪ Asia (Hong Kong, India, Nepal, Pakistan, and Sri Lanka); 

▪ Canada (Alberta, New Brunswick, Nova Scotia, Ontario, and Saskatchewan); 

▪ Europe (Bulgaria, Cyprus, France, Germany, Italy, Netherlands, Sweden, and Turkey) and the 

United Kingdom; 

▪ New Zealand; 

▪ United States (Alabama, Arkansas, Florida, Georgia, Illinois, Indiana, Minnesota, Mississippi, 

Missouri, New Jersey, North Carolina, Oklahoma, Virginia, Washington, West Virginia, 

Wisconsin, and the Northeast); and 

▪ Venezuela. 

 In the contiguous United States, P. macrostoma has not been reported as a widely prevalent1

phytopathogen (Georgia 2011), although, several species in the Phoma genus are considered to be 

relevant phytopathogens. While P. macrostoma is generally regarded as a weak pathogen or wound 

parasite, there are numerous reports of P. macrostoma causing primary disease in plants. Many 

species of Phoma exist as saprobes2

 in the absence of suitable host plants, but will switch to a 

pathogenic existence if a suitable host plant is encountered (Aveskamp et el. 2008). A host list for 

P. macrostoma is available in Boerema and Dorenbosch (1970) and Farr and Rossman (2011). The 

applicant has also provided a list of susceptible plants for P. macrostoma strain 94-44B; it is in the 

Agency’s Environmental Risk Assessment (U.S. EPA 2011c). 

 P. macrostoma strain 94-44B was initially isolated from diseased Canada thistle (Cirsium 

arvense L.), along a roadway in Melfort, Saskatchewan; it has been developed as a microbial pesticide 

for broadleaf weeds in turf and ornamentals. Effects on broadleaf plants include chlorotic leaf spots, 

necrosis, and severe bleaching of emerging leaves. These effects can be lethal, although treated 

plants recover in some cases. The herbicidal action is considered bimodal because the fungal mycelia 

infect plant root systems and produce phytotoxic macrocidins; the macrocidins then cause foliar 

chlorosis and bleaching (Bailey et al. 2010). 

 Taxonomy. The taxonomic designation of Phoma macrostoma is: 

KINGDOM: Fungi ORDER: Sphaeropsidales

DIVISION: Eumycota GENUS: Phoma

SUBDIVISION: Deuteromycotina SPECIES: macrostoma Montagne

CLASS: Coelomycetes VARIETY (VAR.): macrostoma

 

1

A ‘widely prevalent’ organism is one that: might be identified by an experienced farmer; would be able to be identified by 

most experienced county extension agents; would be able to be identified by all experienced diagnosticians at the state level; 

would raise no new regulatory concerns at the state or federal level if it was identified; and is widely distributed in any given 

five year period in the state where the host plant(s) is grown (Georgia 2010).

2

A saprobe is an organism that exists on nonliving organic matter. 
P. macrostoma strain 94-44B page 10 

Biopesticides Registration Action Document 

DRAFT DOCUMENT 

 Morphological Description. The pycnidia (asexual fruiting bodies) are spherical to irregular in shape 

with one or two relatively wide ostioles (small openings or pores from where spores are released from the 

fruiting bodies). The conidial matrix is salmon to flesh colored. Colonies grown on oatmeal agar are 4.5 to 

6 cm after seven days and are sienna to red-wine in color. 

 Growth. Scotts reported that P. macrostoma strain 94-44B grows best at a temperature between 

20 to 25°C (68 to 77°F); however, it will grow in the 10 to 30°C (50 to 86°F) temperature range. Minimal or 

no growth occurs below 5°C (41°F) or above 35°C (95°F). (MRID 479150-26) 

 P. macrostoma as a Biopesticide. P. macrostoma is a fungus and when not reproducing, it 

exists as a spore. Under the right conditions (e.g., a certain temperature, humidity), the spores will start 

to reproduce (germinate) and form mycelia. P. macrostoma strain 94-44B’s pesticidal activity arises 

from the action of macrocidins, which are produced by the mycelia, either in vitro or in situ (Bailey et al. 

2011b). As a pesticide product, P. macrostoma may be active as either a ‘heat-killed’ product or as a 

viable product, with mycelia fragments. With the heat-killed product, the macrocidins are taken up by 

plant roots to produce photobleaching, which results in chlorosis and plant mortality. When the viable 

product is applied to soil, the plant roots become infected, providing for direct delivery of the 

macrocidins into susceptible plants. Nonsusceptible plants may also become infected and take up 

macrocidins; however, the levels of P. macrostoma strain 94-44B are thought to decline over time, with 

no noticeable negative effects on the plants. 

III. ACTIVE INGREDIENT CHARACTERIZATION (40 CFR 158.2120). Most of the product analysis 

data requirements have been met. Once production of these new, proposed pesticide products is 

underway, a final manufacturing process must be submitted (Guideline No 885.1200). Additionally, 

five-batch analyses need to be completed for all three products (Guideline No 885.1400), and three 

studies—stability to normal and elevated temperatures, metals and metal ions (Guideline No

830.6313); storage stability (Guideline No 830.6317); and corrosion characteristics (Guideline No

830.6320) are underway. EPA expects Scotts to submit the results of these studies when they are 

completed. 

A. Product Chemistry and Composition

1. Product Identity (Guideline No 885.1100). The applicant adequately described the 

identity of P. macrostoma strain 94-44B, including how this particular strain is unique 

from other Phoma species (MRID 479150-01; 482810-01). A number of researchers 

have studied P. macrostoma strain 94-44B at the molecular level to differentiate it 

from other species of Phoma and P. macrostoma strains. Their testing includes3

: 

RAPD PCR and DNA PFGE (Zhou et al. 2005); DNA-specific probe (Zhou et al. 

2005); Primer-specific identification of biocontrol isolates; ITS rDNA sequence 

analysis; and AFLP fingerprinting; and genetic mating (Zhou et al. 2005). 

(MRID 479150-01) 

 

2. Manufacturing Process (Guideline No 885.1200). A general description for design 

of a modular manufacturing facility is given; it is acceptable. Once production is 

underway, a final production method needs to be submitted along with five-batch 

analyses for the manufacturing and end-use products. (MRIDs 479150-01, 

 482810-01, 481451-01) 

 

 

3

RAPD PCR=’Random Amplification of Polymorphic DNA’ ‘Polymerase Chain Reaction;’ DNA PFGE=’Deoxyribonucleic acid’ 

‘Pulsed Field Gel Electrophoresis;’ ITS rDNA=’Internal Transcribed Spacer’ ‘Ribosomal DNA;’ AFLP=Amplified Fragment 

Length Polymorphism. 
P. macrostoma strain 94-44B page 11 

Biopesticides Registration Action Document 

DRAFT DOCUMENT 

3. Deposition of a Sample in a Nationally Recognized Culture Collection 

(Guideline No 885.1200). The strain known as Phoma macrostoma strain 94-44B 

was deposited with the International Depositary Authority of Canada (IDAC), National 

Microbiology Laboratory, Public Health Agency of Canada. This accession number 

is IDAC-230201-3. (MRID 479150-01) 

4. Discussion of Unintentional Ingredients (Guideline No 885.1300). In the 

fermentation and production of its P. macrostoma strain 94-44B pesticide products, 

Scotts is aware of stages in the manufacturing process where contamination and 

development of unintentional ingredients may occur. They have protocols in place to 

manage the introduction of human pathogens and manage any contaminated 

batches. (MRIDs 479150-01; 482810-01) 

 In the manufacture of P. macrostoma products, macrocidins are produced in 

the fermentation process. It is the macrocidins that contribute to the overall 

pesticidal activity of these new products. 

B. Analysis and Certified Limits 

1. Analysis of Samples (Guideline No 885.1400). Preliminary analyses have been 

conducted for the Phoma products. Once production is underway, a final production 

method needs to be submitted along with five-batch analyses for the manufacturing 

and end-use products. (MRID 479150-02; 481451-02). 

2. Certification of Limits (Guideline No 885.1500). This requirement was adequately 

addressed. Under 40 CFR 158.350, the “applicant may propose a certified limit for 

an active or inert ingredient that differs from the standard certified limit....” Scotts 

proposed a limit wider than the standard for Phoma TECH, and their rationale was 

reasonable. (MRID 479150-02) 

C. Physical and Chemical Properties. Provided in Table 1 is a summary of the physical and 

chemical properties of P. macrostoma strain 94-44B. With a few exceptions for ongoing 

studies (for example, Scotts has done preliminary work regarding the stability and corrosion 

potential of the Phoma products) all the physical and chemical property requirements have 

been met. (MRIDs 479150-03, 479145-01, and 479146-01) 

 Table 1. Select Physical and Chemical Properties of Phoma macrostoma strain 94-44B 

DATA REQUIREMENT 

( GUIDELINE No) 

TEST 

SUBSTANCE VALUE MRID CLASSIFICATION

Color 

(830.6302) 

TGAIa Brownish-gray Method: Munsell Color 

Chart; observation made 

at room temperature. 

479150-03 Acceptable 

Phoma P Dark brown 479145-01 Acceptable 

Phoma H Dark brown 479146-01 Acceptable 

Physical state 

(830.6303) 

TGAI Powder Method: Visual 

inspection at room 

temperature. 

479150-03 Acceptable 

Phoma P Granule 479145-01 Acceptable 

Phoma H Granule 479146-01 Acceptable 

Odor 

(830.6304) 

TGAI Earthy Method: Olfactory 

inspection at room 

temperature. 

479150-03 Acceptable 

Phoma P Earthy 479145-01 Acceptable 

Phoma H Earthy 479146-01 Acceptable 
P. macrostoma strain 94-44B page 12 

Biopesticides Registration Action Document 

DRAFT DOCUMENT 

DATA REQUIREMENT 

( GUIDELINE No) 

TEST 

SUBSTANCE VALUE MRID CLASSIFICATION

Stability to normal and 

elevated temperatures, 

metals and metal ions 

(830.6313) 

TGAI In progress NA In progress; 

to be submitted 

Storage stability 

(830.6317) 

TGAI Being studied in two container types. 

(MRID 479150-03) NA In progress; to be submitted 

Phoma P Being studied in two container types. 

(MRID 479145-01) NA In progress; to be submitted 

Phoma H Being studied in two container types. 

(MRID 479146-01) NA In progress; to be submitted 

Miscibility (830.6319) “Only required for emulsifiable liquid forms of microbial pesticides” (40 CFR 158.2120). 

Phoma TECH, Phoma P, and Phoma H are solids. 

Corrosion 

characteristics 

(830.6320) 

TGAI Being studied in two container types. 

(MRID 479150-03) NA In progress; to be submitted 

Phoma P Being studied in two container types. 

(MRID 479145-01) NA In progress; to be submitted 

Phoma H Being studied in two container types. 

(MRID 479146-01) NA In progress; to be submitted 

pH (830.7000) 

TGAI 5.53 Method: The pH of a 5% 

solution was measured 

using ASTM E-70 

479150-03 Acceptable 

Phoma P 5.28 479145-01 Acceptable 

Phoma H 5.28 479146-01 Acceptable 

Viscosity (830.7100) “Only required for liquid forms of microbial pesticides” (40 CFR 158.2120); 

Phoma TECH, Phoma P, and Phoma H are solids. 

Bulk density 

(830.7300) 

TGAI 0.4 g/mL 

Method: ASTM E-727 

479150-03 Acceptable 

Phoma P 0.7 g/mL 479145-01 Acceptable 

Phoma H 0.7 g/mL 479146-01 Acceptable aTGAI=technical grade active ingredient. b

NA=Not applicable. 

IV. HUMAN HEALTH RISK ASSESSMENT. In assessing the risk of a pesticide to human health, EPA 

considers the toxicity of the pesticide in addition to exposure routes and levels. Provided in section 

A (below) is the toxicity of P. macrostoma strain 94-44B and in section B, the exposure. The Risk 

Characterization is provided in section C. 

A. Toxicity (40 CFR 158.2140)

1. Acute Toxicity. Provided in Table 2 is a summary of the toxicity data for 

P. macrostoma strain 94-44B. All of the studies are acceptable. 

Table 2. Summary of Submitted Toxicology Data for Phoma macrostoma strain 94-44B 

REQUIREMENT

(GUIDELINE No) MRID TOXICITY AND CLASSIFICATION

a

TOXICITY 

CATEGORY

Acute Oral Toxicity/ 

Pathogenicity 

(885.3050) 

479150-05; 

479150-08 

♂ and ♀ CD rats were given a single oral dose (1.0 × 108 CFU/mL) of P. macrostoma

strain 94-44B spores; it cleared by Day 7 and 21. 

CONCLUSION: the test material was not toxic, infective nor pathogenic via the oral route. bLD50 (combined)>1 × 08

 CFU per animal 

CLASSIFICATION: Acceptable 

IV 
P. macrostoma strain 94-44B page 13 

Biopesticides Registration Action Document 

DRAFT DOCUMENT 

REQUIREMENT

(GUIDELINE No) MRID TOXICITY AND CLASSIFICATION

a

TOXICITY 

CATEGORY

Acute Pulmonary 

Toxicity/Pathogenicity 

(885.3150) 

479150-05; 

479150-09 

♂ and ♀ CD rats given a single intratracheal dose of P. macrostoma strain 94-44B 

spores (1.4 × 108

 CFU per animal) ; viable test substance cleared from the organs. 

CONCLUSION: the test material was not toxic, infective, nor pathogenic 

 via the inhalation route. 

LD50 (combined) >1.4 × 108

 CFU per animal 

CLASSIFICATION: Acceptable 

IV 

Acute Injection 

(

c i.p.) Toxicity/ 

Pathogenicity 

(885.3200) 

479150-05; 

479150-10 

♂ and ♀ CD rats were given a single i.p. dose of P. macrostoma strain 94-44B spores 

(2.5 × 08

 CFU per animal); viable test substance cleared from the organs. 

CONCLUSION: the test material was not toxic, infective, nor pathogenic via the i.p. route. 

 LD50 (combined) >2.5 × 08

 CFU per animal 

CLASSIFICATION: Acceptable 

IV 

Hypersensitivity 

Incidents (885.3400) 

479150-05; 

479150-11 

Scotts submitted a statement summarizing the number of persons who were 

potentially exposed to P. macrostoma during production. No incidents of 

hypersensitivity were reported among these individuals. Scotts stated that they will 

report all hypersensitivity incidents to the Agency if they occur. 

CLASSIFICATION: Acceptable 

NA 

Acute Oral 

Toxicity (870.1100) 

479150-05; 

479150-12 

♂ and ♀ Sprague-Dawley rats were gavaged with a single dose of ground-up 

P. macrostoma strain 94-44B in water (5,000 mg/kg bw); after 14 days of 

observation no treatment-related mortalities or clinical signs of toxicity were seen, 

and no gross findings were observed at necropsy. 

CONCLUSION: The test material is not acutely toxic via the oral route. 

 LD50 (combined) >5,000 mg/kg bw 

CLASSIFICATION: Acceptable 

IV 

Acute Dermal 

Toxicity (870.1200) 

479150-05; 

479150-13 

♂ and ♀ New Zealand White rabbits were exposed via the dermal route to 

4.5 × 104

 CFU/g of ground-up P. macrostoma strain 94-44B. An aqueous paste 

of the test material was applied to an ~240 cm2

 area of exposed skin for 24 hours. 

After 14 days no treatment-related mortalities or clinical signs of toxicity were seen, 

and no gross findings were observed at necropsy. 

CONCLUSION: The test material is not acutely toxic via the dermal route. 

 LD50 (combined)>5,000 mg/kg bw 

CLASSIFICATION: Acceptable 

IV 

Acute Inhalation 

Toxicity (870.1300) 

479150-05; 

479150-14 

Scotts requested a waiver for this requirement because the acute pulmonary 

toxicity/pathogenicity study (MRID 479150-09) showed no signs of acute toxicity 

via the inhalation route. EPA accepts Scotts rationale and has used the results 

of the acute pulmonary toxicity/pathogenicity study to assess the acute inhalation 

toxicity of P. macrostoma strain 94-44B. 

CONCLUSION: P. macrostoma strain 94-44B is not acutely toxic via the inhalation route. 

CLASSIFICATION: Acceptable 

IV 

Acute Eye Irritation 

(870.2400) 

479150-05; 

479150-15 

The eyes of ♀ New Zealand White rabbits were instilled with 0.1g (which contained 

4.5 × 104

 CFU/g) P. macrostoma strain 94-44B; it was left in place for 24 hours. 

Varying degrees of eye irritation was seen in all the animals; after three days 

all irritation resolved. 

CONCLUSION: P. macrostoma strain 94-44B is moderately irritating to the rabbit eye. 

CLASSIFICATION: Acceptable 

III 

Primary Dermal 

Irritation (870.2500) 

479150-05; 

479150-16 

♀ New Zealand White rabbits were exposed via the dermal route to 4.5 × 104 CFU/g 

of P. macrostoma strain 94-44B. An aqueous paste of the test material was 

applied to an ~240 cm2

 area of exposed skin for four hours. After three days there 

were no treatment-related mortalities. Slight erythema was seen shortly after 

exposure; it resolved by 24 hours postapplication. 

CONCLUSION: P. macrostoma strain 94-44B is not a skin irritant. 

CLASSIFICATION: Acceptable 

IV 

a

Category I has the highest toxicity while Category IV has the lowest. For a description of the 

 Toxicity Categories along with their limits, see 40 CFR 156.62. b

LD50=Median lethal dose, which is a statistically derived single dose that can be expected to cause death in 50% of the test animals 

when administered by the route indicated (oral, dermal, inhalation). It is expressed as the amount of test substance per unit weight. c

i.p.=intraperitoneal. 

2. Endocrine Effects. As required by the Administrator under the Federal Food, Drug, 

and Cosmetic Act (FFDCA) section 408(p), EPA has developed the Endocrine 

Disruptor Screening Program (EDSP) and has begun to implement the screening 
P. macrostoma strain 94-44B page 14 

Biopesticides Registration Action Document 

DRAFT DOCUMENT 

program that is to be used to test all pesticides to determine whether certain 

substances (including pesticide active and other ingredients) may have an effect in 

humans or wildlife similar to an effect produced by a “naturally occurring estrogen, or 

other such endocrine effects as the Administrator may designate.” FFDCA section 

408(p)(4), authorizes the Administrator, by order, to exempt from the requirements of 

the Estrogenic Substances Screening Program a biologic substance or other 

substance if a determination is made that the substance is anticipated not to produce 

any effect in humans similar to an effect produced by a naturally occurring estrogenic 

substance. Between October 2009 and February 2010, EPA issued test orders/data 

call-ins for the first group of 67 chemicals, which contain 58 pesticide active 

ingredients and nine inert ingredients. P. macrostoma is not among the group of 58 

pesticide active ingredients on the initial list to be screened under the EDSP. 

 The Agency believes that P. macrostoma likely is a substance that would not 

produce any effect in humans similar to an effect produced by a naturally occurring 

estrogenic substance. As such, pursuant to section 408(p)(4), EPA will determine in 

the future whether it can exempt P. macrostoma from the requirements of EDSP 

section 408(p). In the event the Agency does determine to exempt this substance 

from the EDSP, an order will be issued. For further information on the status of the 

EDSP, the policies and procedures, the list of 67 chemicals, future lists, the test 

guidelines and the Tier 1 screening battery, please visit our website: 

www.epa.gov/endo/. 

B. Exposure. Scotts intends to register two end-use products containing P. macrostoma strain 

94-44B as the active ingredient. Phoma H is intended for homeowner-use and Phoma P is 

meant to be used by individuals working in commercial or agricultural settings. The primary 

difference between Phoma H and Phoma P, in terms of individual exposure, is that Phoma 

P is expected to be applied on a much larger scale than Phoma H. For example, the 

proposed label for Phoma H allows the product to be applied to flower beds by spot 

application. Phoma P can be applied to field-grown nursery flowers by broadcast 

application. 

1. Occupational Exposure. Phoma P is a pesticide product intended for use by 

individuals who will use this product in a commercial or agricultural setting (e.g., lawn 

care, ornamental plant nursery) to control weeds in or around: 

▪ Ornamental Plants (flowers and roses, ground covers, shrubs, and trees); 

▪ Ornamental Grasses; 

▪ Turfgrass (residential lawns, recreational areas, sod farms, 

commercial areas, and golf courses) 

▪ Seed-starting; 

▪ Field-grown nursery and landscape plants; and 

▪ Container uses. 

 Application to ornamental plants and grasses, and turfgrass will be by spot or 

broadcast application, using a spreader. Use of Phoma P in seed starting, field-grown 

nursery and landscape plant application, and container use will be via broadcast application 

(with a spreader). EPA expects that loaders and applicators will be exposed to Phoma P via 

the dermal and inhalation routes, and workers who reenter treated areas will be exposed by 

the dermal route. 
P. macrostoma strain 94-44B page 15 

Biopesticides Registration Action Document 

DRAFT DOCUMENT 

2. Residential, School, and Day Care Exposure. Phoma H is a residential-use 

pesticide product proposed for use in controlling weeds in or around: 

▪ Flowers and roses;

▪ Shrubs;

▪ Trees;

▪ Ornamental Grasses;

▪ Lawns; and 

▪ Seed starting.

 Application to flowers and roses, shrubs, trees, and ornamental grasses will 

be by spot application only; application for lawns and seed-starting will be by spot 

and broadcast application (spreader). Phoma H is sold in packaging designed to 

minimize exposure during application (Messerschmidt 2011). For spot application, 

the product comes in a ready-to-use bottle where the user just needs to agitate the 

product (by turning the bottle) and remove the cap. For broadcast, Phoma H is 

placed in the spreader hopper; the user selects the correct application rate (which is 

listed on the product label) by adjusting a knob on the spreader. 

 Individuals who apply Phoma H are expected to be exposed via the dermal 

and possibly inhalation routes. After application, individuals in and around homes, 

schools, and other such settings may be exposed to Phoma P and/or Phoma H by 

touching plants that have been treated, or walking through or playing on treated turf. 

C. Human Health Risk Characterization. Occupational exposure may occur through the 

dermal and inhalation routes. In acute toxicity testing, study investigators demonstrated that 

P. macrostoma 94-44B has low toxicity via these routes. The dermal LD50 is >5,000 mg/kg 

bw and it is not a skin irritant. In acute pulmonary toxicity pathogenicity testing, instillation of 

1.4 × 108

 CFU per animal into the lungs did not cause adverse effects; based on these 

results, EPA expects that acute inhalation toxicity would also be low. P. macrostoma strain 

94-44B was found to be slightly irritating to the eyes (Toxicity Category III); this concern can 

be mitigated with appropriate label language regarding eye safety. 

 Individuals who apply Phoma H in and around the home are expected to be exposed 

by the dermal and inhalation routes; however, such exposure is expected to be low. The 

packaging and labeling for Phoma H is designed to minimize exposure during application. 

An additional source of dermal exposure (to Phoma P and H) would be from touching plants 

that have been treated, or walking through or playing on treated turf. As discussed above, 

the dermal toxicity of P. macrostoma strain 94-44B is low, and, the environmental fate data 

show that P. macrostoma strain 94-44B is unlikely to persist at high levels for long periods of 

time. 

 Based on the available toxicity and exposure information, EPA concludes that there 

is little risk to handlers, workers, bystanders, and others from the intended use of 

P. macrostoma strain 94-44B, as labeled. 

V. ECOLOGICAL RISK ASSESSMENT AND ENDANGERED SPECIES ASSESSMENT

A. Ecological Risk Assessment. Similar to human health risk assessment, in assessing the 

risk to nontarget4

 organisms, the Agency considers: the organisms likely to be exposed and 

their exposure level; the toxicity of the pesticide to the nontarget organisms; and whether the 

exposure will cause harmful effects. The effects can be direct (e.g., fish die from a pesticide 

entering waterways, birds do not reproduce normally after ingesting contaminated fish), or 

indirect (a hawk becomes sick from eating a mouse dying from pesticide poisoning). The 

 

4

A nontarget organism is an organism other than that which the pesticide is intended to kill. 
P. macrostoma strain 94-44B page 16 

Biopesticides Registration Action Document 

DRAFT DOCUMENT 

data requirements for nontarget toxicity and environmental fate of microbial pesticides can 

be found at 40 CFR 158.2150. Table 3, under section 1, below, lists the ecotoxicity data 

requirements and how they were met. Section 2 describes the environmental fate of P. 

macrostoma strain 94-44B when used as a pesticide product, and section 3 provides the 

environmental risk characterization. 

1. Effects of Phoma macrostoma strain 94-44B to Nontarget Organisms 

(Ecotoxicity) (40 CFR 158.2150). In assessing the toxicity of a pesticide to the 

nontarget organisms, the Agency requires a number of Tier I ecotoxicity tests on 

nontarget terrestrial (e.g., birds, plants) and aquatic (e.g., fish) organisms; Tier I 

testing is considered to be the worst-case. Depending on the nature of the active 

ingredient, Tier II testing (environmental expression) may be automatically required; 

otherwise, it may be triggered by results seen in Tier I testing. 

 The scientific evidence from peer-reviewed literature and the results and 

information from studies conducted by the applicant are sufficient to satisfy all Tier I 

data requirements; Table 3 provides a summary of the submitted ecotoxicity data. 

With respect to Tier II requirements, the peer-reviewed literature (e.g., Bailey et al. 

2010; Bailey et al. 2011a,b; and Zhou et al. 2004), which described the infection and 

colonization processes in plants and the environmental fate of P. macrostoma strain 

94-44B, adequately satisfy Tier II testing, provided that certain risk mitigation 

measures are implemented. For details on the submitted data, see EPA’s 

Environmental Risk Assessment (U.S. EPA 2011c). 

 The Agency also sought respective opinions from the U.S. Department of 

Agriculture’s (USDA) Animal Plant and Health Inspection Service (APHIS) Plant 

Protection and Quarantine (PPQ) program, and a plant pathologist at Cornell 

University concerning P. macrostoma as a plant pathogen and its ecological 

relevance as a plant pathogen, relative to other pathogenic species of Phoma. 

 Table 3. Summary of Submitted Ecotoxicity Data for Phoma macrostoma strain 94-44B 

REQUIREMENT

(GUIDELINE No) MRID TOXICITY AND CLASSIFICATION

Avian oral toxicity 

(885.4050) 

479150-18 30-day oral LD50: > 2.22 × 105

 CFU/kg bw/day 

CLASSIFICATION: Supplemental; adequate for EPA risk assessmenta

Avian inhalation 

toxicity/pathogenicity 

(885.4100) 

study not 

required 

“Data required when the nature of the microbial pesticide and/or its toxins indicates potential 

pathogenicity to birds” (40 CFR 158.2150, testnote 3); P. macrostoma is not known or 

shown to be an avian pathogen. 

Wild mammal 

toxicity/pathogenicity 

(885.4150) 

479150-26 “Required on a case-by-case basis if results of tests required by §158.2140 are inadequate or 

inappropriate for assessment of hazards to wild mammals” (40 CFR 158.2150, testnote 4). 

Scotts submitted rationale regarding why this study is not needed. They argued that 

P. macrostoma is ubiquitous and P. macrostoma strain 94-44B has been shown to decline in 

population after application. 

The rat LD50 rat for the submitted acute oral toxicity study (MRID 479150-12) 

is >5,000 mg/kg bw. 

CLASSIFICATION: Acceptable rationale 

Freshwater fish toxicity/ 

pathogenicity (885.4200) 

479150-19 32-day b

LC50: >2.9 × 103 CFU/mL; no adverse effects were observed. 

CLASSIFICATION: Acceptable 

Freshwater invertebrate 

toxicity/pathogenicity 

(885.4240) 

479150-20 21-day cEC50: > 3.78 × 102 CFU/mL d

NOAEC: 2.71 × 103 CFU/mL; based on growth and reproduction. 

CLASSIFICATION: Acceptable 

Estuarine/Marine fish 

testing (885.4280) studies not 

required 

“Required if the product is intended for direct application into the estuarine or marine environment 

or expected to enter this environment in significant concentrations because of expected use or 

mobility pattern” (40 CFR 158.2150, testnote 6). Significant concentrations are not expected to 

reach marine/estuarine environments as a result of the proposed uses. 

Estuarine and marine 

invertebrate testing 

(885.4280) 
P. macrostoma strain 94-44B page 17 

Biopesticides Registration Action Document 

DRAFT DOCUMENT 

REQUIREMENT

(GUIDELINE No) MRID TOXICITY AND CLASSIFICATION

Nontarget plant 

testing (885.4300) 

479150-21 Aquatic:

(Lemna gibba)

7-day EC50 =1.51 × 104

 CFU/mL; 

NOAEC=4.4 × 103

 CFU/mL CLASSIFICATION: 

Both studies are 

acceptable 

483184-01 Terrestrial: A collection of studies showed that P. macrostoma strain 

94-44B is toxic/pathogenic to several species of terrestrial 

broadleaf plants. 

Nontarget insect 

 testing (885.4340) 

479150-23 Green lacewing. 15-day LC50: >1 × 106 CFU/mL diet CLASSIFICATION: 

All studies are 

acceptable 

479150-24 Lady bird beetle. 12-day dietary LC50: > 1 × 106 CFU/mL diet 

479150-22 Parasitic hymenoptera. 16-day dietary LC50: > 1 × 106 CFU/mL 

Honey bee 

testing (885.4380) 

479150-25 5-day LC50: >1 × 106

 CFU/mL diet; the study was not long enough to assess pathogenicity. 

CLASSIFICATION: Supplemental; adequate for EPA risk assessment a

Viability of the test substance was not confirmed, which is necessary for an ‘Acceptable’ rating from Health Canada’s PMRA; 

nonetheless, the study is acceptable for EPA risk assessment purposes. 

b

LC50=Median Lethal Concentration, which is a statistically derived concentration of a substance that can be expected to cause 

death in 50% of test animals. It is usually expressed as the weight of substance per weight or volume of water, air or feed (e.g., 

mg/L, mg/kg). 

c

EC50= Effective Concentration, which is the concentration of the test substance at which the 

 respiration rate is 50% of that shown by the control. 

d

NOAEC=no-observed-adverse-effect-concentration.

2. Environmental Fate. The environmental fate data show that P. macrostoma strain 

94-44B is unlikely to persist at high levels for long periods of time or move great 

distances when applied to turf and ornamentals. Regarding its fate when used as a 

pesticide product, EPA concludes that: 

▪ Macrocidins may be mobilized by runoff when soils are saturated; some 

movement into adjacent areas could occur via this process5 (Bailey et al. 2011b). 

▪ Significant runoff is expected with applications to impervious surfaces. 

▪ Persistence is expected within treated areas with repeated applications. Studies 

show a declining trend after four months and survival of susceptible plants after 

one year has varied. 

 In soil, P. macrostoma was observed to begin declining in viable numbers 

after two months and to below detection after one year, though in 

experiments where sunflower was sown a year after exposure some 

chlorosis but no decrease in emergence was seen when compared to 

controls (MRID 479150-01). 

3. Environmental Risk Characterization. In assessing the environmental risk that 

use of Phoma P and Phoma H may pose to the environment, the Agency considered 

the submitted data, environmental fate and exposure considerations from the 

proposed labels (e.g., apply product on a calm day), and information from the open 

literature. EPA concludes that: 

▪ Exposure of nontarget organisms to P. macrostoma strain 94-44B and/or 

macrocidins may occur in the terrestrial environment as a result of the 

proposed applications. 

 For turf and ornamental applications, exposures are expected to be 

limited to the treated site and immediately adjacent area. Long-term or 

frequent use in treated areas may lead to effects on susceptible rotational 

 

5

Please Note: macrocidins taken up by roots produce chlorosis and disease in a dose-dependent manner regardless of viable 

P. macrostoma presence.
P. macrostoma strain 94-44B page 18 

Biopesticides Registration Action Document 

DRAFT DOCUMENT 

crop species. Significant offsite movement and nontarget exposures are 

expected with applications to impervious surfaces (e.g., patios, 

driveways, sidewalks). The proposed labels, however, do not include 

impervious surfaces as use sites. 

▪ Significant exposures of nontarget organisms to P. macrostoma strain 94-44B 

and/or macrocidins are not expected in aquatic environments. 

▪ Adverse effects to birds, wild mammals, nontarget insects, honey bees, 

freshwater fish and invertebrates, marine/estuarine fish and invertebrates, and 

aquatic plants are not expected. 

▪ Offsite, some species of nontarget plants may be adversely affected where 

significant exposure occurs. 

▪ Nontarget plant effects may be significant for susceptible species in treated 

areas, which may be a concern for susceptible rotational dicotyledonous plants. 

▪ Effects to nontarget plants beyond the treated sites are expected to be limited 

to immediately adjacent areas for applications to turf and ornamentals, and 

effects will be limited to more highly susceptible species. 

Please note that the Agency may require additional testing if uses are expanded, if 

formulations change for the end-use products, or if incidents of adverse effects to 

nontarget organisms occur during commercial use of these products. 

B. Threatened and Endangered Species Assessment. Adverse effects to terrestrial 

vertebrates, nontarget insects, and freshwater and marine/estuarine animals and plants are 

not expected to occur due to exposure resulting from the proposed labeled applications of 

P. macrostoma strain 94-44B. Therefore, a no effect6

 determination is made for direct 

effects to federally listed threatened and endangered (listed) species within these taxa as a 

result of all proposed applications as labeled. 

1. Direct Effects. While the proposed applications are not expected to result in 

widespread losses of nonlisted, nontarget terrestrial plants, the potential for sublethal 

or lethal effects to individual listed terrestrial plants cannot be precluded. The 

potential occurrence of listed plants in treated areas may be unlikely, but it is 

unknown. Drift or runoff of the end-use product may deposit P. macrostoma strain 

94-44B in areas containing listed plants. The proposed labels include use directions 

intended to limit drift. For example, the proposed Phoma P label states: “Apply only 

on a calm day when wind speed is less than 5 miles per hour.” Even though 

exposure may not result in mortality, it can cause sublethal necrosis and chlorosis 

that may contribute to reduced survival and reproduction of a listed plant. The 

proposed applications of P. macrostoma strain 94-44B, therefore, have the unlikely 

potential to directly affect individual listed terrestrial plants. 

2. Indirect Effects and Effects to Critical Habitat. Effects to terrestrial vertebrates, 

nontarget insects, and freshwater and marine/estuarine animals and plants are not 

expected to occur as a result of proposed applications of P. macrostoma strain 

 94-44B. Therefore, indirect effects to listed species dependent on these taxa and 

related effects to their critical habitat7

 are not expected and a no effect determination 

 

6

The U.S. Fish and Wildlife Service defines the term ‘no effect’ to mean that “its proposed action will not affect a listed species or designated 

critical habitat” (www.fws.gov/endangered/esa-library/pdf/CH1-3.PDF). 

7

The term ‘critical habitat’ means “areas that contain the physical or biological features that are essential to the conservation of the species 

that may need special management or protection” (www.fws.gov/endangered/). 
P. macrostoma strain 94-44B page 19 

Biopesticides Registration Action Document 

DRAFT DOCUMENT 

is made for indirect and habitat effects to listed species dependent on these taxa for 

all proposed applications. 

 The proposed applications of P. macrostoma strain 94-44B are not expected 

to result in widespread effects to nonlisted terrestrial plants, so indirect effects to 

listed generalist species8

 that are dependent on plants are not expected. EPA 

makes a no effect determination for indirect and habitat effects to all listed species 

that do not have an obligate relationship with any particular species of plant. 

Significant effects may occur in certain susceptible plant species, so applications of 

P. macrostoma strain 94-44B could affect a nonlisted (or listed) plant upon which a 

listed species depends exclusively for food or habitat. Therefore, applications of 

P. macrostoma strain 94-44B have the potential to cause indirect effects to listed 

species and also critical habitat for listed species with obligate relationships to 

susceptible plants; however, such a scenario has not been identified. 

VI. RISK MANAGEMENT 

A. Risk Mitigation 

1. General. The application methodology and equipment should be clarified on the 

label. And, specific use sites for turf (e.g., sod farms, golf courses) are not provided; 

they should be clarified on the label. 

2. Environmental. To reduce exposure to terrestrial nontarget organisms, the 

following label language must be used: “Immediately water but do not saturate the 

soil.” Bailey et al. (2011b) show that macrocidins may be mobilized by runoff when 

soils are saturated. With such label language, runoff into adjacent areas as a result 

of applications to turf and ornamentals is expected to be minimized. Care should 

also be taken to not apply these products when soils are saturated (Bailey et al. 

2010).

B. Future Changes to the Use Pattern. The Agency has the authority to require additional 

testing if uses are expanded, if formulations change for the end-use products, or if incidents 

of adverse effects occur during use of these products. 

VII. REGISTRATION ELIGIBILITY DETERMINATION

A. Decision. The Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA) section 3(c)(5) 

provides for the registration of new active ingredients if EPA determines that: (1) its 

composition is such as to warrant the proposed claims for it; (2) its labeling and other 

materials required to be submitted comply with the requirements of FIFRA; (3) it will perform 

its intended function without unreasonable adverse effects on the environment; and (4) 

when used in accordance with widespread and commonly recognized practice, it will not 

generally cause unreasonable adverse effects on the environment. 

 The four eligibility criteria for registration of new active ingredients are satisfied for 

Phoma P and Phoma H. These products are not expected to cause unreasonable adverse 

effects to human health or the environment. Therefore, the new active ingredient P. 

macrostoma strain 94-44B is eligible for registration for the labeled uses. Please note, 

however, that certain terms of registration must be met. 

 

8

In terms of ecology, a plant-eating ‘generalist’ (as opposed to a ‘specialist’) is a species that is able to eat a wide-variety of plants more or 

less equally (e.g., deer), whereas a specialist depends on a single or narrow range of plants (e.g., Koala bear). 
P. macrostoma strain 94-44B page 20 

Biopesticides Registration Action Document 

DRAFT DOCUMENT 

B. Terms of the Registration. As terms of registration, EPA requires that the following 40 

CFR 158.2120 data requirements under be completed. Most of these data are confirmatory; 

Scotts has informed the Agency that all the studies are underway. 

PRODUCT CHEMISTRY AND COMPOSITION

 Manufacturing Process 

(Guideline No 885.1200) 

Once production of these new pesticide products is underway, 

a final manufacturing process needs to be submitted. 

ANALYSIS AND CERTIFIED LIMITS

 Five-Batch Analysis 

(Guideline No 885.1400) 

Required for Phoma TECH, Phoma H, and Phoma P. 

PRODUCT CHEMISTRY AND COMPOSITION

Stability to Normal and 

Elevated Temperatures, 

Metals and Metal Ions 

(Guideline No 830.6313)

Required for the technical product. 

Storage Stability 

(Guideline No 830.6317) 

Required for Phoma TECH, Phoma H, and Phoma P. 

Corrosion Characteristics 

(Guideline No 830.6320) 

Required for Phoma TECH, Phoma H, and Phoma P. 

VIII. ENVIRONMENTAL JUSTICE. EPA seeks to achieve environmental justice—the fair treatment 

and meaningful involvement of all people, regardless of race, color, national origin, or income— with 

respect to the development, implementation, and enforcement of environmental laws, regulations, and 

policies. To help address potential environmental justice issues, the Agency seeks information on any 

groups or segments of the population who, as a result their location, cultural practices, or other factors, 

may have atypical, unusually high exposure to P. macrostoma strain 94-44B, compared to the general 

population. 

 
P. macrostoma strain 94-44B page 21 

Biopesticides Registration Action Document 

DRAFT DOCUMENT 

BIBLIOGRAPHY 

Studies, by MRID

479145-00 Scotts. 2009. Submission of Product Chemistry Data in Support of the Application for Registration of 

PHOMA P. The Scotts Company. Transmittal of 1 Study. November 16, 2009. 

479145-01 Mendenhall, T. 2009. Bioherbicide End Product (EP): Physical and Chemical Characteristics: Color, 

Physical State, Odor, pH, Bulk Density. Corrosion, Storage Stability and Colony Forming Units, and 

Moisture Content. Project Number: SS/235. Unpublished study prepared by The Scotts Company, 

LLC. 15 p. November 16, 2009. 

479146-00 Scotts. 2009. Submission of Product Chemistry Data in Support of the Application for Registration of 

PHOMA H. The Scotts Company. Transmittal of 1 Study. November 16, 2009. 

479146-01 Mendenhall, T. 2009. Physical and Chemical Characteristics: Color, Physical State, Odor, pH, Bulk 

Density, Corrosion, Storage Stability and Colony Forming Units, and Moisture Content: S-13739: 

Bioherbicide End Product. Project Number: SS/235. Unpublished study prepared by The Scotts 

Company. 15 p. November 16, 2009. 

479150-00 Scotts. 2009. Submission of Product Chemistry, Toxicity, and Fate Data in Support of the Application 

for Registration of Phoma Technical. The Scotts Company. Transmittal of 26 Studies. November 16, 

2009. 

479150-01 Falk, S.; Bailey, K.; Canale, A. 2009. Phoma Technical: Product Chemistry and Composition. 

Unpublished study prepared by The Scotts Company and Agriculture & Agri-Food Canada. 96 p. 

November 16, 2009. 

479150-02 Falk, S.; Bailey, K.; Canale, A. 2009. Phoma Technical: Analysis and Certified Limits. Unpublished 

study prepared by The Scotts Company and Agriculture & Agri-Food Canada. 26 p. November 16, 

2009. 

479150-03 Mendenhall, T. 2009. Bioherbicide TGAI: S-12642: Physical and Chemical Characteristics: Color, 

Physical State, Odor, pH, Bulk Density, Corrosion, Storage Stability and Colony Forming Units, and 

Moisture Content. Project Number: SS/236. Unpublished study prepared by The Scotts Company. 

15 p. November 16, 2009. 

479150-04 Messerschmidt, O.; Bailey, K. 2009. Phoma Technical: Physical and Chemical Characteristics: 

Storage Stability. Unpublished study prepared by OMC Ag Consulting and Agriculture & Agri-Food 

Canada. 11 p. November 16, 2009. 

479150-05 Wilkinson, G.; Messerschmidt, O. 2009. Phoma Technical: Mammalian Toxicology Data Summary. 

Unpublished study prepared by OMC Ag Consulting and The Scotts Company. 10 p. November 16, 

2009. 

479150-06 Gingras, B. 2009. Batch Sample Viability of Two Microbial Pest Control Agent (MPCA) Preparations: 

Final Report. Project Number: 2199/SN1, 2199. Unpublished study prepared by IIT Research 

Institute. 25 p. November 16, 2009. 

479150-07 Gingras, B. 2009. Sensitivity of Detection of Material B, the Spores of Phoma macrostoma, for 

Toxicity/Pathogenicity Testing in Rats: Final Report. Project Number: 2199/SN2, 2199. Unpublished 

study prepared by IIT Research Institute. 44 p. November 16, 2009. 

479150-08 Lyang, N. 2009. Toxicity/Pathogenicity Testing of Phoma macrostoma, following Acute Oral 

Challenge in Rats: Final Report. Project Number: 2199/SN3, 2199. Unpublished study prepared by 

IIT Research Institute. 79 p. November 16, 2009. 

479150-09 Lyang, N. 2009. Toxicity/Pathogenicity Testing of Material B, the Spores of Phoma macrostoma, 

following Acute Intratracheal Challenge in Rats: Final Report. Project Number: 2199/SN4. 

Unpublished study prepared by IIT Research Institute. 73 p. November 16, 2009. 

479150-10 Gingras, B. 2009. Toxicity/Pathogenicity Testing of Material B, the Spores of Phoma macrostoma, 

following Acute Intraperitoneal Challenge in Rats: Final Report. Project Number: 2199/SN5. 

Unpublished study prepared by IIT Research Institute. 75 p. November 16, 2009. 

479150-11 Wilkinson, G.; Messerschmidt, O. 2009. Tier 1 Studies: Reporting of Hypersensitivity Incidence (in 

Humans). Unpublished study prepared by The Scotts Company and OMC Ag Consulting. 4 p. 

November 16, 2009. 
P. macrostoma strain 94-44B page 22 

Biopesticides Registration Action Document 

DRAFT DOCUMENT 

479150-12 Johnson, W. 2009. Acute Oral Toxicity Study of Material C, the Ground End-Use Product (EP) of 

Phoma macrostoma, in Rats. Project Number: 2199/001, 2199/001/SN1. Unpublished study 

prepared by IIT Research Institute. 30 p. November 16, 2009. 

479150-13 Johnson, W. 2009. Acute Dermal Toxicity Study of Material C, the Ground End-Use Product of 

Phoma macrostoma, in Rabbits. Project Number: 2199/001, 2199/001/SN4. Unpublished study 

prepared by IIT Research Institute. 32 p. November 16, 2009. 

479150-14 Wilkinson, G.; Messerschmidt, O. 2009. Tier 1 Studies: Mammalian Toxicology Data Waiver 

Request: Acute Inhalation (in Rats). Unpublished study prepared by OMC Ag Consulting and The 

Scotts Company. 4 p. November 16, 2009. 

479150-15 Johnson, W. 2009. Acute Eye Irritation Study of Material C, the Ground End-Use Product (EP) of 

Phoma macrostoma in Rabbits. Project Number: 2199/001, 2199/001/SN2. Unpublished study 

prepared by IIT Research Institute. 30 p. November 16, 2009. 

479150-16 Johnson, W. 2009. Acute Dermal Irritation Study of Material C, the Ground End-Use Product (EP) of 

Phoma macrostoma, in Rabbits. Project Number: 2199/001, 2199/001/SN3. Unpublished study 

prepared by IIT Research Institute. 28 p. November 16, 2009. 

479150-17 Wilkinson, G.; Messerschmidt, O. 2009. Nontarget Organisms and Environmental Fate Data 

Summary. Unpublished study prepared by The Scotts Company and OMC Ag Consulting. 10 p. 

November 16, 2009. 

479150-18 Hubbard, P.; Beavers, J. 2008. Phoma macrostoma: An Avian Oral Pathogenicity and Toxicity Study 

in the Northern Bobwhite. Project Number: 560/104. Unpublished study prepared by Wildlife 

International Ltd. 51 p. November 16, 2009. 

479150-19 Gallagher, S.; Krueger, H. 2009. Phoma macrostoma: A Five-Concentration Toxicity and 

Pathogenicity Test with the Rainbow Trout (Oncorhynchus mykiss): Final Report. Project Number: 

560A/110. Unpublished study prepared by Wildlife International, Ltd. 66 p. November 16, 2009. 

479150-20 Gallagher, S.; Krueger, H. 2009. Phoma macrostoma: A 21-Day Life-Cycle Toxicity and 

Pathogenicity Test with the Cladoceran Daphnia magna: Final Report. Project Number: 560A/109A, 

560/010808/DAP/TP/SUB560. Unpublished study prepared by Wildlife International, Ltd. 74 p. 

November 16, 2009. 

479150-21 Gallagher, S.; Krueger, H. 2009. Phoma macrostoma: A 7-Day Static-Renewal Toxicity Test with 

Duck Weed (Lemna gibba G3): Final Report. Project Number: 560A/108. Unpublished study 

prepared by Wildlife International, Ltd. 53 p. November 16, 2009. 

479150-22 Porch, J.; Krueger, H. 2009. Phoma macrostoma: A Dietary Pathogenicity and Toxicity Study with 

Parasitic Hymenoptera (Pediobius foveolatus): Final Report. Project Number: 560/107. Unpublished 

study prepared by Wildlife International, Ltd. 33 p. November 16, 2009. 

479150-23 Porch, J.; Krueger, H. 2009. Phoma macrostoma: A Dietary Pathogenicity and Toxicity Study with 

Green Lacewing Larvae (Chrysoperla rufilabris): Final Report. Project Number: 560/106. 

Unpublished study prepared by Wildlife International Ltd. 33 p. November 16, 2009. 

479150-24 Porch, J.; Krueger, H. 2009. Phoma macrostoma: A Dietary Pathogenicity and Toxicity Study with 

the Ladybird Beetle (Hippodamia convergens): Final Report. Project Number: 506/108. Unpublished 

study prepared by Wildlife International, Ltd. 32 p. November 16, 2009. 

479150-25 Porch, J.; Sindermann, A.; Krueger, H. 2009. Phoma macrostoma: A Dietary Pathogenicity and 

Toxicity Study with the Honey Bee (Apis mellifera): Final Report. Project Number: 560/105. 

Unpublished study prepared by Wildlife International, Ltd. 31 p. November 16, 2009. 

479150-26 Wilkinson, G.; Messerschmidt, O. 2009. Tier 1 Studies: Nontarget Organisms and Environmental 

Fate Data Waiver Request. Unpublished study prepared by The Scotts Company and OMC Ag 

Consulting. 10 p. November 16, 2009. 

481451-00 Scotts. 2010. Submission of Product Chemistry Data in Support of the Applications for Registration of 

Phoma Tech, Phoma H and Phoma P. The Scotts Company. Transmittal of 3 Studies. July 8, 2010. 

481451-01 Falk, S.; Canale, A. 2010. Product Chemistry and Composition: Phoma Technical. Unpublished 

study prepared by The Scotts Company. 17 p. July 8, 2010. 

481451-02 Falk, S.; Canale, A. 2010. Product Chemistry and Composition: Phoma Technical. Unpublished 

study prepared by The Scotts Company. 5 p. July 8, 2010. 
P. macrostoma strain 94-44B page 23 

Biopesticides Registration Action Document 

DRAFT DOCUMENT 

481451-03 Wilkinson, G.; Messerschmidt, O. 2010. Nontarget Organisms and Environmental Expression Data 

Waiver Requests: Phoma Technical. Unpublished study prepared by The Scotts Company. 13 p. 

July 8, 2010. 

482810-00 Scotts. 2010. Submission of Product Chemistry Data in Support of the Applications for Registration of 

Phoma Tech, Phoma H and Phoma P. The Scotts Company. Transmittal of 1 Study. November 1, 

2010. 

482810-01 Falk, S.; Bailey, K.; Canale, A. 2010. Product Chemistry and Composition (Response to Joint 

PMRA/EPA Review Letter of August 23, 2010): Phoma Technical. Unpublished study prepared by 

The Scotts Company. 27 p. November 1, 2010. 

483184-00 Scotts. 2010. Submission of Efficacy Data in Support of the Applications for Registration of Phoma 

Tech, Phoma H and Phoma P. The Scotts Company. Transmittal of 1 Study. December 10, 2010. 

483184-01 Bailey, K.; Falk, S.; Derby, J. 2010. Host Range Testing on Terrestrial Plants to Determine 

Pathogenicity to Phoma macrostoma 94-44B. Unpublished study prepared by Agriculture Canada and 

The Scotts Company. 19 p. December 10, 2010. 

Reviews and other References

Aveskamp, M.M.; De Gruyter, J.; and Crous, P.W. 2008. Biology and recent developments in the systematic of 

Phoma, a complex genus of major quarantine significance. Fungal Diversity. 31:1-18. 

AAFC. 2009. AAFC Biopesticide: Phoma macrostoma. Government of Canada. Agriculture and Agri-Food Canada. 

2009. AAFC No. 10777; Cat. No. A52-120/1-2009E-PDF; ISBN 978-1-100-10941-1 

Bailey, K.L.; Pitt, W.M.; Derby, J.; Walter, S.; W. Taylor, W.; and Falk, S. 2010. Efficacy of Phoma macrostoma, a 

bioherbicide, for control of dandelion (Taraxacum officinale) following simulated rainfall conditions. Am. J. Plant Sci. 

Biotech., 4 (Special Issue 2):35-42. 

Bailey, K.L.; Pitt, W.M.; Leggett, F.; Sheedy, C.; and Derby, J. 2011a. The effects of Phoma macrostoma on nontarget 

plant and target weed species. Biol. Control, on-line publication available June 14, 2011. 

Bailey, K.L.; Pitt, W.M.; Leggett, F.; Sheedy, C.; and Derby, J. 2011b. Determining the infection process of Phoma 

macrostoma that leads to bioherbicidal activity on broadleaved weeds. Biol. Control, 2011, doi: 

10.1016/j.biocontrol.2011.06.019. 

Boerema, G.H., and M.M.J. Dorenbosch. 1970. On Phoma macrostomum Mont., a ubiquitous species on woody 

plants. Persoonia, 6:49-58. 

Farr, D.F. and Rossman, A.Y. 2011. U.S. Department of Agriculture. Agriculture Research Service. Systematic 

Mycology and Microbiology Laboratory. Fungal Databases. Retrieved November 1, 2011, from /fungaldatabases/ 

Georgia. 2011. Widely Prevalent Fungi of the United States. University of Georgia, Center for Invasive Species and 

Ecosystem Health. Last web update: October 6, 2010. www.prevalentfungi.org/fungi.cfm. 

Messerschmidt. 2011. Email from Olav Messerschmidt, OMC Ag Consulting to Kathleen Martin, U.S. Environmental 

Protection Agency. November 14, 2011. 

U.S. EPA. 2011a. Memorandum from Joel Gagliardi to Kathleen Martin. Phoma macrostoma Montagne strain 94-44B: 

Human health risk assessment following joint EPA-PMRA reviews. U.S. Environmental Protection Agency Office of 

Pesticide Programs. Biopesticides and Pollution Prevention Division. February 8, 2011. 

U.S. EPA. 2011b. Memorandum from Joel Gagliardi to Kathleen Martin. Phoma macrostoma Montagne strain 94-44B. 

U.S. Environmental Protection Agency. Biopesticides and Pollution Prevention Division. Microbial Pesticides Branch. 

September 15, 2011. 

U.S. EPA. 2011c. Memorandum from Shannon Borges to Kathleen Martin. Environmental risk assessment for the 

FIFRA Section 3 registration of Phoma macrostoma strain 94-44B (PC Code 080303; EPA Reg. Nos. 239-ETNE, 239-

ETNG, 239-ENTU) for control of broadleaf weeds in turf and ornamentals. U.S. Environmental Protection Agency 

Office of Pesticide Programs. Biopesticides and Pollution Prevention Division. November 2, 2011. 

Zhou, L.; Bailey, K.L. ; and Derby J. 2004. Plant colonization and environmental fate of the biocontrol fungus Phoma 

macrostoma. Biological Control 30 (2004) 634–644. 

Zhou, L.; Bailey, K.L.; Chen, C.Y.; and Keri, M. 2005. Molecular and genetic analyses of geographic variation in 

isolates of Phoma macrostoma used for biological weed control. Mycologia, 97(3), 2005, pp. 612–620.