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EPA BIOPESTICIDES AND POLLUTION PREVENTION DIVISION 

COMPANY NOTICE OF FILING FOR PESTICIDE PETITIONS PUBLISHED IN 

THE FEDERAL REGISTER 

Marrone Bio Innovations

0F7681

 EPA has received a pesticide petition 0F7681 from Marrone Bio Innovations, 

proposing, pursuant to section 408(d) of the Federal Food, Drug, and Cosmetic Act 

(FFDCA), 21 U.S.C. 346a(d), to amend 40 CFR part 180 to establish an exemption from 

the requirement of a tolerance for the microbial pesticide Streptomyces acidiscabies

strain RL-110T

 Pursuant to section 408(d)(2)(A)(i) of FFDCA, as amended, Marrone Bio 

Innovations has submitted the following summary of information, data, and arguments 

in support of their pesticide petition. This summary was prepared by Marrone Bio 

Innovations and EPA has not fully evaluated the merits of the pesticide petition. The 

summary may have been edited by EPA if the terminology used was unclear, the 

summary contained extraneous material, or the summary unintentionally made the reader 

conclude that the findings reflected EPA’s position and not the position of the petitioner. 

I. Marrone Bio Innovations Petition Summary

 0F7681

A. Product Name and Proposed Use Practices

MBI-005 TGAI is a highly selective biological herbicide containing killed, nonviable Streptomyces acidiscabies strain RL-110T

 cells. MBI-005 controls pre-emergent 

and post-emergent broadleaf and sedge weeds in cereal grains, corn, sugarcane and turf. 

For pre-emergent control, MBI-005 should be applied to the soil prior to weed and crop 

emergence. For post-emergent control, apply MBI-005 as a foliar spray. When applied to 

targeted weeds, MBI-005 will result in a necrosis of actively growing portions resulting 

in plant death. Proper timing of application to newly emerged weeds is important for 

optimal results. MBI-005 should be applied to weeds that are 3 inches in height or less. 

For optimum results, MBI-005 should be applied to targeted weed species shortly after 

germination. Thorough coverage of weed foliage is necessary for effective control. 

B. Product Identity/Chemistry 

1. Identity of the pesticide and corresponding residues. MBI-005 TGAI consists 

of the fermentation solids of killed, non-viable Streptomyces acidiscabies strain RL-110T
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cells. Streptomyces acidiscabies strain RL-110T selectively targets broadleaf and sedge 

weeds in cereal grains, corn, sugarcane and turf. It is expected when used as proposed,

Streptomyces acidiscabies strain RL-110T would not result in residues that are of 

toxicological concern.

 2. Magnitude of residues at the time of harvest and method used to determine the 

residue. It is expected when used as proposed, Streptomyces acidiscabies strain RL-110T

would not result in residues that are of toxicological concern.

 3. A statement of why an analytical method of detecting and measuring the levels 

of the pesticide residue are not needed. An analytical method for residues is not 

applicable. It is expected when used as proposed, Streptomyces acidiscabies strain RL110T

 would not result in residues that are of toxicological concern.

C. Mammalian Toxicological Profile

A variety of toxicity studies have been performed with MBI-005. The toxicity 

studies performed are listed below in Table 1 and include an acute oral toxicity study in 

rats, an acute dermal toxicity study in rats, an acute inhalation toxicity study in rats, acute 

intravenous toxicity studies in rats, acute dermal irritation study in rabbits, an acute eye 

irritation and toxicity study in rabbits, and a skin sensitization study in guinea pigs. The 

oral, dermal and inhalation routes of exposure are the routes relevant for human health 

risk assessment. When mammals were exposed through oral and dermal routes, the 

results of these studies consistently showed that MBI-005 was non-toxic and also lacked 

irritation as well as sensitization potential. Following inhalation of undiluted MBI-005, 

the test substance was rated as moderately toxic in rats, with toxic effects seen at the site 

of inhalation, the lungs, effects that were accompanied by significant decreases in rat 

body weight at day 14. Given that human inhalation exposure would not be to undiluted 

liquid substance, the relevance of these data to risks associated with undiluted MBI-005 

is minimal. The results of the intravenous toxicity study showed that MBI-005 containing 

S. acidiscabies strain RL-110T

 was not pathogenic in mammals. No reports of 

hypersensitivity have been recorded from personnel working with this organism. As 

evidenced by the results of toxicity testing summarized below in Table 1, there is no 

anticipated risk to human health following exposure to MBI-005 through oral, dermal or 

inhalation routes. 

TABLE 1 

Summary of MBI-005 Mammalian Toxicity Data 

Mammalian Toxicity Test Species Dose Tested Results 

(Date Completed) 

Acute oral toxicity 

Kuhn 2009 

(OPPTS No. 870.1100) 

Rat 5000 mg/kg Non-toxic 

(June 4, 2009) 

Acute dermal toxicity 

Kuhn 2009a 

Rat 5050 mg/kg Non-toxic 

(August 21, 2009) 
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(OPPTS No. 870.1200 and 

OECD 402) 

Acute inhalation toxicity 

Younger 2009 

(OPPTS No. 870.1300 and 

OECD 403) 

Rat 2.21 mg/L (undiluted 

liquid test substance 

for 4 hours) 

Moderate toxicity 

(September 1, 2009) 

Acute intravenous toxicity 

Monds 2009 

(OPPTS No. 885.3200) 

Rat 9.0 x 107 cfu/ml Non-toxic, nonpathogenic 

(December 29, 2009) 

Acute dermal irritation 

Kuhn 2009d 

(OPPTS No. 870.2500 and 

OECD 404) 

Rabbit 0.5 ml undiluted 

product for 4 hours 

Non-irritating 

Category IV 

(July 31, 2009) 

Acute eye irritation 

Kuhn 2009c 

(OPPTS No. 870.2400 and 

OECD 405) 

Rabbit 0.1 ml undiluted 

product for 24 hours 

Minimal irritant 

Category IV 

(August 4, 2009) 

Skin sensitization 

Kuhn 2009e 

(OPPTS No. 870.2600) 

Guinea 

pig 

0.4 ml undiluted test 

substance (given once 

per week for 3 weeks, 

followed by a 2 week 

period before 

challenge) 

Not sensitizing 

(September 18, 2009) 

D. Aggregate Exposure

 1. Dietary exposure.

i. Food. Dietary exposure from use of MBI-005, as proposed, is minimal. The 

intended use of the product is to apply MBI-005 as a spray to crops pre-emergent 

and post-emergent (i.e., rice, cereal grains, sugarcane, corn, including field corn, 

seed corn, popcorn, and corn grown for seed, and turf, including turf grown for 

seed) for the control of broadleaf and sedge weeds. Due to the long period of time 

from application to harvest residues would be minimal. Furthermore, the results 

of toxicity testing following acute oral exposure, the route most relevant to 

assessment of risks to health from exposure to food, indicate there is no risk to 

human health or the environment from MBI-005. There are no reports of 

ecological or human health hazards related to oral exposure to Streptomyces sp. or

Streptomyces acidiscabies strain RL-110T. The absence of acute toxicity in 

laboratory animals following oral exposure to high doses of the product 

demonstrates the benign nature of MBI-005. 

ii. Drinking water. Similarly, exposure of humans to residues of MBI-005 in 

drinking water would be minimal based on the proposed application rates and 

methods. Results of the acute oral toxicity testing described above have shown 
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that MBI-005 was non-toxic at high test dose (> 5000 mg/kg). There are no 

reports of ecological or human health hazards related to oral exposure to 

Streptomyces sp. or Streptomyces acidiscabies strain RL-110T. The absence of 

acute toxicity in laboratory animals following oral exposure to high doses of the 

product demonstrates the benign nature of MBI-005.

2. Non-dietary exposure. The potential for non-dietary exposure to the general 

population, including infants and children, is unlikely as the proposed use sites are 

application to growing plants or crops. The results of toxicity testing discussed 

above indicate there is no risk to human health or the environment from MBI-005. 

There are no reports of ecological or human health hazards related to oral 

exposure to Streptomyces sp. or Streptomyces acidiscabies strain RL-110T. The 

absence of acute toxicity in laboratory animals following oral or dermal exposure 

to high doses of MBI-005 demonstrates the benign nature of the product. 

Although some effects were observed in animals exposed through inhalation to 

high doses of the undiluted MBI-005 product, such exposure would not be seen in 

the general population as the product is diluted before application. As a result, 

non-dietary exposures would not be expected to pose any quantifiable risk.

E. Cumulative Effects

It is not expected that, when used as proposed, MBI-005 would result in residues 

that are of toxicological concern. The intended use of the product is to apply MBI 005 as 

a pre-emergent or post-emergent spray to crops (i.e., rice, cereal grains, sugarcane, corn, 

including field corn, seed corn, popcorn, and corn grown for seed, and turf, including turf 

grown for seed) for control of broadleaf and sedge weeds. Application of MBI-005 to 

crops will not result in a substantial increase in concentration in the environment, in 

particular since the active ingredient in MBI-005 is decomposed and detoxified when 

exposed to biological systems (King et al. 2000. J. Agric. Food Chem. 48:512-514). As 

indicated in studies by Doumbou et al. (1998; Appl. Environ. Microbiol. 64:4313-4316) 

and Lazarovits et al. (2004; Can J. Microbiol. 50:121-126), thaxtomin A is rapidly 

degraded by ubiquitous soil organisms such as Ralstonia sp., Penicillium sp., and 

Trichoderma sp. More specifically, it was shown that about 75% of thaxtomin A was 

converted into less phytotoxic thaxtomin transformation products during a 4-day 

incubation with a common fungus Aspergillus niger (Lazarovits et al., 2004). The results 

of toxicity testing indicate there is no risk to human health or the environment from MBI005. There are no reports of ecological or human health hazards related to exposure to 

Streptomyces sp. or Streptomyces acidiscabies strain RL-110T. The absence of acute 

toxicity in laboratory animals following exposure to high doses of the product 

demonstrates the benign nature of MBI-005. The lack of acute toxicity indicates that the 

hazard associated with the use of MBI 005 is low.

F. Safety Determination

1. U.S. population. Acute toxicity studies have shown that the MBI-005 is nontoxic in mammals when exposure is through oral or dermal routes, lacks irritation 
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and sensitization potential in mammals, and is only toxic to mammals via 

inhalation when the exposure is to high doses of undiluted material, an exposure 

scenario that is not relevant to the general population. Further, testing in 

mammals of active microbes showed that the product was not pathogenic. The 

intended use of MBI-005 is as a pre-emergent or post-emergent spray to crops 

(i.e., rice, cereal grains, surgarcane, corn, including field corn, seed corn, popcorn, 

and corn grown for seed, and turf, including turf grown for seed) for control of 

broadleaf and sedge weeds. The results of toxicity testing indicate there is no risk 

to human health or the environment from MBI-005. There are no reports of 

ecological or human health hazards caused by Streptomyces acidiscabies in 

general. The lack of acute toxicity indicates that the hazard associated with the 

use of MBI-005 is low. There is a reasonable certainty of no harm to the general 

United States population from exposure to this active ingredient.

2. Infants and children. As mentioned above, it is not expected that, when used as 

proposed, MBI-005 would result in residues that are of toxicological concern. 

There is a reasonable certainty of no harm for infants and children from exposure 

to MBI-005 from the proposed uses. 

G. Effects on the Immune and Endocrine Systems 

To date there is no evidence to suggest that MBI-005 functions in a manner 

similar to any known hormone, or can act as an endocrine disrupter.

H. Existing Tolerances

There are no current tolerances or tolerance exemptions in place for Streptomyces 

acidiscabies strain RL-110T

I. International Tolerances

There are no current tolerances or tolerance exemptions in place for Streptomyces 

acidiscabies strain RL-110T