This is a proposal by a Subcommittee of the National Organic Standards Board (NOSB). Proposals are posted for public comment and then may be 

voted upon by the full Board. They are not final Board recommendations or NOP policy. 

Revised June 20 2013

National Organic Standards Board

Crops Subcommittee

Petitioned Material checklist

Streptomycin

August 6, 2013

Discussion Summary: 

The NOSB has been petitioned to remove the existing expiration date of October 21, 2014 for Streptomycin 

and replace it with a new one of Oct 21, 2017, for both apples and pears. The petitioner states that this would 

allow adequate time for the transition from strep over to non-antibiotic, biological alternatives for fire blight 

control.

There are two different positions on this subject: those that support the petition request for an extension and 

those that oppose an extension.

Both sides agree that it is time for a phase out for the allowed use of strep. The supporters believe that three 

additional years until October 2017 is reasonable, and opponents believe that yet another extension offers no 

assurance of phase out.

Proponents of an extension feel that:

~Because of the investment involved to establish an orchard (as well as the businesses established to 

handle this produce) in both time, money, and the need for completion of existing research of 

materials, that a slowdown (or extension) of the expiration date is needed, especially for pear 

growers.

~This slow down would benefit growers, processors, producers, handlers, and consumers alike.

~Alternative materials are still not readily showing consistent control and one material’s registration 

(Previsto copper) has been delayed by EPA. Thus, the farmers still need some additional time in 

order to prepare for the transition to a non-antibiotic fire blight control period in time.

•Opponents feel that:

~Fire blight resistance to streptomycin is widespread in the U.S.

~Raise the question of essentiality, based on the significant percentage of growers selling to markets 

that do not allow antibiotic treatments.

~Organic integrity and sales are threatened because of consumer expectation that antibiotics are not 

used in organic production.

•Both sides agree that the “core” issue here is whether or not there is a risk of enhancing antibiotic resistance 

in human pathogens. There is science that supports both sides of this argument and the level of concerns that 

are raised by this particular use pattern. Supporters cite issues of use patterns and limits of residues as 

indicative of no evidence of harm. Opponents cite resistant human pathogens in strep treated orchards and 

horizontal gene transfer identified as leading to antibiotic resistance.

•While there has been a direct linkage shown to exist between infection and colonization of humans by 

antibiotic resistant bacteria in animals (Larsen et al 2010), supporters cite no direct linkage has been 

demonstrated between antibiotic resistant bacteria in humans and antibiotic sprays applied to plants (Stockwell 

and Duffy, 2012), such as the current use of strep in apples and pears for fire blight control. Lab results vary in 

their conclusions. Opponents cite evidence that bacteria, including Erwinia amylovora and human pathogens, 

share a common genetic basis for resistance, transmitted by plasmids, to streptomycin in particular. (McGhee 

et al, 2010; Sundin, 2000; Sundin and Bender, 1996; Pezzella et al, 2004; Scherer et al, 2013; Foster et al, 

2004.)

•Proponents state: there is no evidence that applications of antibiotics to orchards during bloom contributes to 

antibiotic resistance in human pathogens. The amount and timing of the use of strep in an orchard environment 
This is a proposal by a Subcommittee of the National Organic Standards Board (NOSB). Proposals are posted for public comment and then may be 

voted upon by the full Board. They are not final Board recommendations or NOP policy. 

Revised June 20 2013

does not contribute to any human health concerns, especially in light of streptomycin being ineffective in 

humans when ingested orally.

•Opponents state: there is evidence that an application of strep leads to an increase in resistance to 

streptomycin in orchard bacteria, that human pathogens and fire blight bacteria share the same gene pool of 

genes resistant to streptomycin (i.e. that the same genes responsible for resistance in Erwinia amylovora are 

also responsible for resistance in human pathogens), that human pathogens do not need to be present in the 

orchard to obtain resistance genes acquired by and augmented in orchard bacteria, that strep residues are 

sometimes present in treated fruit, and that strep is still a critically important antimicrobial for use against 

human pathogens.

•The primary point of discussion here is whether to grant an extension or not to the current expiration date for 

streptomycin in October 2014. The points proponents say should be considered are: What impact does an 

extension/or non-extension have on the stakeholders that either use this material or have built their businesses 

around expanded crop availability; How will a decision impact the supply chain, How will a decision impact the 

consumer (all consumers, not just a select group(s)), What are the risks/if any for granting an extension or not, 

and would granting a short extension for allowed use knowing what the use patterns are pose any significant 

increases in human health concerns from resistance than currently exist today? 

•The points opponents say should be considered are: What impact does yet another extension, which was first 

called for by the NOSB in 1995, have on the integrity of the organic label? What are the public health hazards 

of using antibiotics for nontherapeutic uses and why are infectious disease doctors concerned? What is the 

threat of low-level environmental exposure to antibiotics? What are the alternative strategies that are used to 

manage or prevent fire blight?

•Remember, according to proponents, this is not a new material, but one that has been on the National List of 

Approved Materials for a number of years as being allowed for use by organic growers to use on their 

organically grown and certified crops. Opponents point to long-standing NOSB attempts to phase out the use 

of antibiotics in organic apple and pear production, with votes by previous boards to phase-out, only to have 

subsequent boards issue extensions.

•One other point of discussion, proponents state, would be how to ensure a full expiration of strep from the 

National List, if an extension for use were to happen. They ask, how could we ensure all stakeholders that 

there would be an absolute point when this usage would truly expire? Opponents, who would like the 2014 

antibiotic expiration date to take effect, believe that the debate on antibiotics and votes to phase them out by 

previous boards have resulted in only extended deadlines for too long, and organic should not in any way 

contribute to the worldwide crisis in antibiotic resistance, while ultimately threatening consumer confidence in 

the organic label.

Summary of Proposed Action:

The Crops Subcommittee proposes to: 

Remove the existing expiration date of October 21, 2014 for streptomycin and replace that with a new 

expiration date of October 21, 2017. This would be for use in both apples and pears for control of fire blight.

The Crops Subcommittee puts forward this resolution:

Resolution: The National Organic Standards Board is committed to the phase out of this material. Between 

now and the expiration date the Board urges growers and certifiers to include in organic systems plans an 

annual increase in the extent and/or number of alternative practices and materials that are trialed for controlling 

fire blight. In addition, the board strongly advocates to USDA a high priority for increased support for research 

into these alternative practices and materials.
This is a proposal by a Subcommittee of the National Organic Standards Board (NOSB). Proposals are posted for public comment and then may be 

voted upon by the full Board. They are not final Board recommendations or NOP policy. 

Revised June 20 2013

Introduction

A Petition to the National Organic Standards Board (NOSB) was received for the Removal of the Expiration 

Date (October 21, 2014) for streptomycin and the establishment of October 21, 2017 as its sunset date, in 

order to allow for adequate time for the transition to proven effective non-antibiotic, i.e. biological alternatives 

for fire blight control in apples and pears.

Because this subject is complex and there are two different positions to be represented, this recommendation 

is organized to present two separate positions - those for and those against an extension. These are designed 

to supplement the points raised in the checklist. Most of the same background presented in the Spring 2013 

Recommendation for Oxytetracycline is relevant to Streptomycin, except for the 2007 and 2008 actions.

The subcommittee acknowledges the concerns of consumers and previous NOSB members who feel that it is 

time to phase this material out from organic agriculture. The two positions represented in the discussion 

section of this document differ on the timing of the phase-out. Additional concerns are being put forward in a 

separate resolution on the subject.

Points of Agreement and Disagreement

This section focusses on how the material is used in the context of both plant and human health. Because 

much of the general information was covered in the proposal for Oxytetracycline, this review focusses on the 

differences and similarities between the two materials. Specific portions address Checklist categories as noted.

1. Fire blight control

Proponents of both positions agree that orchard establishment requires a large investment of time and money, 

that apples and pears are grown in a variety of locations that require different management plans, and that 

more research is needed into systems for preventing fire blight damage. 

Proponents of extending the expiration date of streptomycin say:

Because of the very large investment of time and money that establishing an orchard entails, the 

variety of locations that apples and pears are grown, and the very rudimentary state of research on 

alternatives to this material in that variety of locations, we are supporting slowing down the removal of 

streptomycin from the National List.

Since the organic pear industry is more at risk to fire blight than apples there is concern that pear 

research and control measures are lagging behind and that an expanded time frame will be needed.

Streptomycin is still fairly widely used in pears, especially those grown in areas with high humidity and 

warm springs.

A slightly extended date of 2017 will benefit consumers and growers alike. The few more seasons of 

research will enable new products to be tested in both apples and pears in a variety of weather 

conditions.

In 2009, about 15% of the total apple area and 40% of the pears (organic and conventional) were 

treated with streptomycin or oxytetracycline for control of Fireblight, the disease caused by the bacteria 

Erwinia amylovora.

1

Experience of pear growers especially in the 2013 season has shown that Blossom Protect has not 

worked well in the Pacific Northwest or California. It was an unusually warm spring. The copper 

material that is very promising has been delayed in registration until at least 2014 nationwide and 2015 

in California.
This is a proposal by a Subcommittee of the National Organic Standards Board (NOSB). Proposals are posted for public comment and then may be 

voted upon by the full Board. They are not final Board recommendations or NOP policy. 

Revised June 20 2013

Opponents to extending the expiration date of streptomycin say:

Like most challenges in organic production systems, with fire blight there is no one material and no one 

practice that will eliminate the problem. Fire blight must be met with a truly organic systems approach 

that is sensitive to the potential adverse health and environmental effects of inputs and consumer 

expectations.2

Fire blight resistance to streptomycin is widespread in the United States. Streptomycin-resistant strains 

of fire blight have been found in California, Oregon, Washington, Michigan, New York,3 Missouri,4 and 

Utah.5 Plasmid-borne genes have been found to confer resistance in California, Michigan,6 and New 

York.7

With regard to the “essentiality” of streptomycin, not all organic apple and pear growers depend on 

antibiotics. In fact, there is a sizeable proportion of growers of both apples and pears who do not use 

antibiotics. 

As of March 10, 2011, there were 96 businesses certified as EU-compliant organic producers of apples 

and/or pears in the state of Washington alone, representing about one third of the state’s organic apple 

and one fourth of the state’s organic pear production. EU-compliant organic apple and pear growers 

cannot use antibiotics, and face a three-year ban from selling in the EU if they do.8 In addition, cultural 

changes in the orchard environment have contributed to epidemics of fire blight.9

2. Need for phase out of streptomycin

The sub-committee acknowledges the concerns of consumers and previous NOSB members who feel that it is 

time to phase this material out from organic agriculture. The two positions represented in the discussion 

section of this document differ on the timing of the phase-out.

Proponents of an extension for streptomycin say:

Because of the need to make sure that this material is phased out, a resolution motion has been added to 

affirm the commitment by the NOSB to all organic stakeholders. The NOSB must ensure that the decisions 

made reflect due consideration of the various needs and concerns of the vast array of all our organic 

stakeholders, especially when dealing with complicated issues, such as this one. 

Additionally, in spite of the claims below about the threat of spreading resistance to streptomycin, most of the 

research on this subject has been conducted with antibiotics used in livestock and very little in orchard 

environments. Some very recent research specifically for an orchard situation noted that more streptomycinresistant isolates were cultured from non-sprayed orchards compared to sprayed orchards.10

Opponents of an extension for streptomycin say:

Streptomycin is an antibiotic considered by the World Health Organization to be of critical importance to human 

medicine.11 Streptomycin is used in a way that exposes bacteria in the orchard to the antibiotic.12 Current 

science shows that environmental exposure to antibiotic use in the environment is the major cause of 

development and spread of antibiotic resistance in human pathogens.13The spread of antibiotic resistance 

does not require contact between the antibiotic and human pathogens because the major means of spreading 

antibiotic resistance is through the transfer of genes between different bacteria. Uses resulting in low residues 

(subtherapeutic or subinhibitory levels) can create a high health risk.14 Streptomycin resistance is evident and 

expected to grow if urgent use precaution is not exercised.15 Organic production should not be contributing to 

the problem of antibiotic resistance.

3. Antibiotic Resistance

Proponents and opponents of extending the expiration date of streptomycin agree that the core issue here is 

whether there is a risk of enhancing antibiotic resistance in human pathogens. The most astute and 

experienced scientists in this area realize that science and medicine have to find a way to co-exist with 

resistance, including managing reservoirs of resistance in the environment and preventing development of new 

forms of resistance. (Am. Academy of Microbiology, 2009).
This is a proposal by a Subcommittee of the National Organic Standards Board (NOSB). Proposals are posted for public comment and then may be 

voted upon by the full Board. They are not final Board recommendations or NOP policy. 

Revised June 20 2013

Proponents of extending the expiration date of streptomycin say:

Antibiotic-resistant bacteria that are competent phyllosphere colonisers can persist in the environment, 

evidently independent of antibiotic use, as shown by Yashiro and McManus (2012). They demonstrated 

that long-term applications of streptomycin alone did not alter the bacterial communities on apple leaves. 

They sampled leaves from four orchards that were treated with spring-time applications of streptomycin 

over 10 years and from four orchards that were not sprayed with antibiotics. The bacterial genera Massilia, 

Methylobacterium, Pantoea, Pseudomonas, and Sphingomonas were detected from all orchards, 

regardless of spray history. More streptomycin-resistant isolates (65%) were cultured from non-sprayed 

orchards compared to sprayed orchards (50%). They concluded that factors other than streptomycin 

influence both the proportion of streptomycin-resistant bacteria and phylogenetic makeup of bacterial 

communities on apple leaves (Yashiro and McManus, 2012).

There are numerous reports that the use of antibiotics in animal production is associated with increase of 

antibiotic-resistant bacteria in animals, waste-water, and manure (for some examples see Larsen 2010, 

Wright 2010). A direct linkage was reported between infection and colonization of humans by antibiotic 

resistant bacteria from farm animals (Larsen et al 2010). No direct linkage has been demonstrated 

between antibiotic resistant bacteria in humans and antibiotic sprays on plants (Stockwell and Duffy, 2012).

Opponents of extending the expiration date of streptomycin say:

Application of streptomycin leads to an increase of streptomycin resistance in the fireblight organism and 

other bacteria in the orchard. 

Selection of bacteria resistant to streptomycin occurs at extremely low antibiotic concentrations.16 It is 

accepted that reliance on streptomycin for fireblight control resulted in the development and spread of 

resistance to streptomycin in E. amylovora.17 Resistance genes are prevalent in treated soils,18 and 

researchers have concluded that resistance is often acquired through gene transfer.19 Some researchers found 

the highest concentration of streptomycin-resistant bacteria in the phylloplane of treated crops,20 but Yashiro 

and McManus (2012)21 found a higher percentage of cultured phyllosphere bacteria resistant to streptomycin 

at non-sprayed orchards than at sprayed orchards. But they stated, 

However, our conclusion does not absolve streptomycin of all risk associated with its use. For example, 

it is possible that streptomycin could select for novel resistance genes in apple orchards, even if the 

overall frequency of resistant bacteria is not increased. A greater diversity of mobile resistance genes in 

apple orchards could lead to horizontal transfer of resistance among a greater range of bacteria, which 

in turn could be consumed on fresh produce.

Streptomycin resistance genes from the orchard are transferable to other bacteria.

Streptomycin resistance in E. amylovora may come from a chromosomal or two known streptomycin resistance 

genes carried on plasmids.22 “The carriage of strA-strB within an integron, a transposon, and on broad-hostrange plasmids has facilitated the world-wide dissemination of this determinant among at least 21 bacterial 

genera.”23 The streptomycin resistance genes (strA-strB) are known to be carried on transposons and spread 

by horizontal gene transfer, but are unlikely to have been transferred directly –it is more likely that they are 

spread through intermediate bacteria. “The distribution of the strA-strB genes in the environment clearly 

illustrates the expansiveness of a common microbial gene pool and the rapid dissemination of Abr

determinants in bacterial populations.” 24 This has been confirmed by a several researchers.25

Streptomycin is a critically important antimicrobial.

Streptomycin is classified as a critically important antimicrobial by the World Health Organization. It is a limited 

therapy as part of treatment of enterococcal endocarditis and Multi-Drug Resistant (MDR) tuberculosis.26 It is 

also effective in treating Brucella (brucellosis), Calymmatobacterium granulomatis (donovanosis, granuloma 

inguinale), Escherichia coli, Proteus spp., Aerobacter aerogenes, Klebsiella pneumoniae, and Enterococcus 

faecalis in urinary tract infections, Francisella tularensis, Haemophilus ducreyi (chancroid), Haemophilus 

influenzae (in respiratory, endocardial, and meningeal infections - concomitantly with another antibacterial 

agent), Klebsiella pneumoniae pneumonia (concomitantly with another antibacterial agent), Mycobacterium 
This is a proposal by a Subcommittee of the National Organic Standards Board (NOSB). Proposals are posted for public comment and then may be 

voted upon by the full Board. They are not final Board recommendations or NOP policy. 

Revised June 20 2013

tuberculosis, Pasteurella pestis, Streptococcus viridans, Enterococcus faecalis (in endocardial infections -

concomitantly with penicillin).27

4. Ecological Impacts

Opponents of extending the use of streptomycin say:

Streptomycin use may have unforeseen ecological impacts.

Since resistance to antibiotics is more prevalent in some groups of microorganisms than others, the dispersal 

of streptomycin in the environment can disrupt the microbial ecology. For instance, blue-green algae, which are 

important in sequestering carbon dioxide and releasing oxygen gas, are as a group susceptible to antibiotics.28

Differences between Streptomycin and Oxytetracycline

•• Use: While tetracycline is only used during bloom and will only be present on fruit that set early in the bloom 

period while the late blooms are being sprayed, streptomycin is registered for use from early bloom until 45 

days before harvest. 

•• Mode of Action: Streptomycin binds irreversibly to bacterial ribosomes and block synthesis of proteins (51). 

Oxytetracycline binds reversibly to these proteins (McManus et al., 2002). (Category 1, Question 9]

•• Mechanism of Resistance: There are 2 mechanisms of resistance to streptomycin in fire blight bacteria: 

spontaneous mutation of a chromosomal gene which encodes production of ribosomal protein, thus strep 

cannot bind to ribosome and bacteria becomes immune to antibiotic. This is most common in the US. 

Acquired resistance has been detected occasionally in MI and CA. The pathogen acquired plasmids that 

contained genes encoding an enzyme that inactivates strep. These resistant isolates of fire blight were 

detected in an orchard ten years after applications were stopped (34). The fire blight bacteria has not been 

known to develop resistance to tetracycline in the laboratory, and little is known about the mechanisms for 

resistance to tetracycline in that bacteria.

** Genetics of Resistance: The genes for resistance to streptomycin that are transferred by plasmid are the 

same genes known to confer resistance to streptomycin in human pathogens.29 This is a step in the chain 

of causation that is not known for tetracycline.

•• Residue on Fruit: While there were not specific studies besides EPA data that set ADI limits that showed 

residue of tetracycline on fruit, one study in Austrian orchards showed detection of streptomycin residues 

(33) in apples, with the highest concentrations in the apple core. Apple fruit were collected about three 

months after bloom and tested for streptomycin. The level of detection was 2 μg/kg (0.002 ppm or 2 ppb) 

and the limit of quantification was identified as 7 μg/kg (0.007 ppm or 7 ppb). They reported that the highest 

concentration of streptomycin detected was 18 μg/kg (0.018 ppm), well below the EPA tolerance of 250 

μg/kg (0.25 ppm). The Austrian ADI for streptomycin is 0.03 mg per kg of body mass per day (0.03 ppm). 

The study did not report on exactly what spray practices led to this result.)[Category 1, Question 9]

•• Use in medicine: Both tetracycline and streptomycin are classified as critically important antimicrobials by 

the World Health Organization. Tetracycline is one of a limited number of therapies for infections due to 

Brucella, Chlamydia spp. and Rickettsia spp. Streptomycin is a Limited therapy as part of treatment of 

enterococcal endocarditis and Multi-Drug Resistant (MDR) tuberculosis. Tetracycline has a higher priority 

because it is used more frequently for specific uses, which could lead to faster spread of resistance. 

Tetracycline is administered orally, while streptomycin is administered by injection.30 It is unclear what link 

there may be between oral ingestion and the build-up of resistance to injected streptomycin.

Conclusions

Those supporting an extension of streptomycin use say:

There is no evidence that applications of antibiotics to orchards during bloom contributes to antibioticresistance in human pathogens. Human pathogens have not been found in orchards and would have to be 

present for the resistance genes to transfer. Naturally occurring streptomycin resistant bacteria may be minor 
This is a proposal by a Subcommittee of the National Organic Standards Board (NOSB). Proposals are posted for public comment and then may be 

voted upon by the full Board. They are not final Board recommendations or NOP policy. 

Revised June 20 2013

components of the overall bacterial communities found on apple flowers and in soils, but their presence is 

independent of the antibiotic application. The amount and timing of the use of this material in an orchard 

environment does not contribute to any human health concerns, especially in light of streptomycin being 

ineffective in humans when ingested orally.

Those opposing an extension of streptomycin use say:

There is evidence that application of streptomycin leads to increase resistance to streptomycin in orchard 

bacteria, that human pathogens and the fire blight bacteria share the same gene pool of genes resistant to 

streptomycin (i.e., that the same genes responsible for resistance in Erwinia amylovora are also responsible for 

resistance in human pathogens), that human pathogens do not need to be present in the orchard to obtain 

resistance genes acquired by and augmented in orchard bacteria, that streptomycin residues are sometimes 

present in treated fruit, and that streptomycin is still a critically important antimicrobial for use against human 

pathogens. In light of the crisis of antibiotic resistance, we cannot allow streptomycin use to be extended in 

organic production.

Evaluation Criteria (see attached checklist for criteria in each category)

Criteria Satisfied? 

1. Impact on Humans and Environment ☒ Yes ☐ No ☐ N/A 

2. Essential & Availability Criteria ☒ Yes ☐ No ☐ N/A

3. Compatibility & Consistency ☒ Yes ☐ No ☐ N/A 

Substance Fails Criteria Category: NA 

Recommended Subcommittee Action & Vote, including classification recommendation (state actual motion):

Classification Motion: Streptomycin is synthetic and is already classified as such on the National List so 

there was no need to make a motion to that effect.

Listing Motion: To remove existing expiration date of October 21, 2014 for streptomycin on 

§205.601(i)(11), and replace it with an expiration date of October 21, 2017,” so that the listing reads: (11) 

Streptomycin, for fire blight control in apples and pears only until October 21, 2017.

Motion by: Harold Austin 

Seconded by: Zea Sonnabend

Yes: 5 No: 3 Absent: 0 Abstain: 0 Recuse: 0

Additional Motion: Resolution: The National Organic Standards Board is committed to the phase out of 

this material. Between now and the expiration date the Board urges growers and certifiers to include in 

organic systems plans an annual increase in the extent and/or number of alternative practices and 

materials that are trialed for controlling fire blight. In addition, the board strongly advocates to USDA a high 

priority for increased support for research into these alternative practices and materials.

Motion by: Harold Austin

Seconded by: Zea Sonnabend

Yes: 8 No: 0 Absent: 0 Abstain: 0 Recuse: 0

 Approved by Jay Feldman, Subcommittee Chair, to transmit to NOSB August 6, 2013
This is a proposal by a Subcommittee of the National Organic Standards Board (NOSB). Proposals are posted for public comment and then may be 

voted upon by the full Board. They are not final Board recommendations or NOP policy. 

Revised June 20 2013

NOSB Evaluation Criteria for Substances Added To the National List

Crops or Livestock

Category 1. Adverse impacts on humans or the environment? Substance: Streptomycin 

Question Yes No N/A Comments/Documentation (TAP; petition; 

regulatory agency; other)

1. Is there a probability of 

environmental contamination 

during use or misuse? 

[§6518(m)(3)]

X X The petition claims the manufacturing process 

as CBI. However, the 2011 TR (lines 314-315) 

states, “Dzhedzhev et al. (1975) reported that 

the manufacture of streptomycin resulted in 

high atmospheric concentrations of the 

solvents butyl alcohol and butyl acetate in the 

workplace.” The TR also says (lines 315-332) 

Streptomycin is produced using fermentation, 

a process that usually involves the use of 

solvents and gases that may be discharged 

into water or air, subject to EPA permits. The 

TR concludes (lines 326-328) that assuming 

streptomycin manufacturers comply with 

applicable water and air regulations; it is 

unlikely that environmental contamination will 

result from the fermentation process. (March 

8, 2011 TR – lines 326-328) also in that same 

TR, lines 334-341 states that no surface 

residue can be found on pear or apple trees 

after four to six weeks following a spray 

application(Gardan and Manceau (1984)). 

Also in this same section the EPA (1988) 

states streptomycin residues are nondetectable (<0.5ppm) on crops when treated 

according to label use rates and directions. 

TR lines 414-415 states that the RED for 

streptomycin concluded that agricultural 

streptomycin products, labeled and used 

according to EPA regulations, will not pose 

unreasonable risks or adverse effects to the 

environment (EPA 1992). There is an EPA 

registration review of streptomycin underway 

that is scheduled to be completed in 2014.

2. Is there a probability of 

environmental contamination 

during, manufacture or disposal? 

[§6518(m)(3)]

X X See above for detailed explanation

3. Does the substance contain inerts 

classified by EPA as ‘inerts of

toxicological concern’? [§6517 

(c)(1)(B)(ii)]

X

4. Is there potential for detrimental 

chemical interaction with other 

materials used in organic farming 

systems?

[§6518(m)(1)]

X Streptomycin should not be applied following 

an application of a Bordeaux mixture and it is 

incompatible with lime sulfur (according to the 

2002 HSDB) (March 8, 2011 TR lines 357 & 

358).
This is a proposal by a Subcommittee of the National Organic Standards Board (NOSB). Proposals are posted for public comment and then may be 

voted upon by the full Board. They are not final Board recommendations or NOP policy. 

Revised June 20 2013

5. Is there a toxic or other adverse 

action of the material or its 

breakdown products?

[§6518(m)(2)]

X X March 8, 2011 TR (lines 338) states that strep 

breakdowns into products that include 

methylamine, carbon dioxide, and urea, all of 

which occur naturally in the environment. (EPA 

1988, 1992) EPA cited data that showed that 

streptomycin biodegrades relatively quickly in soil 

and water.

Streptomycin can be phytotoxic to plants; therefore 

it is sprayed on the surface of plants rather than 

injected (McManus and Stockwell, 2000). Most 

apple and pear producers are prudent in their use 

of streptomycin sprays to reduce costs and to 

prevent the development of streptomycin-resistant 

strains of Erwinia amylovora. Disease risk models 

help producers optimize the timing of antibiotic 

sprays and reduce the total number of 

applications. These measures can help reduce the 

development of antibiotic resistance. (March 8, 

2011 TR lines 111-115)

There is a high probability that streptomycin 

resistant bacteria are present in the environment 

as a consequence of pesticidal use of streptomycin 

(EPA, 2006a). (TR lines 429-431) The HED 

Chapter of the TRED states that there have been 

reports of adverse effects resulting from use of

streptomycin as a pesticide (EPA, 2006a). (TR 

lines 449-450) Because of the risk to workers, 

personal protective equipment is advised to 

prevent skin contact with streptomycin, and 

workers are not permitted re-entry into treated 

areas for at least 12 hours. (TR lines 454-456)

6. Is there persistence or 

concentration of the material or 

breakdown products in the 

environment? [§6518(m)(2)]

X X A certain background level of streptomycin is 

expected in soil due to the natural presence of the 

bacterium Streptomyces griseus (Brosche, 2010). 

EPA (1988, 1992) cited data that show that 

streptomycin biodegrades relatively quickly in soil 

and water. (TR lines 207-210). The breakdown 

products include methylamine, carbon dioxide, and 

urea, all of which occur naturally in the 

environment. Therefore, the application of 

streptomycin for control of fire blight in apples and 

in pears in accordance with labeled instructions is 

unlikely to contaminate the environment. (TR lines 

337-341).

According to EPA, streptomycin is moderately 

persistent in aerobic soil (a single value of t1/2= 

17.5 days was determined). EPI Suite estimated a 

shorter aerobic soil half-life (t1/2= 25 days) and a 

longer sediment half-life (t1/2= 100 days). Given 

the moderate persistence/high mobility and 

solubility of streptomycin, the chemical is expected 

to dissipate relatively slowly and at the same time 

be vulnerable to leaching/run-off. (TR lines 217-

225) Gardan and Manceau (1984) reported that no 

surface residue of streptomycin was detectable on 

pear or apple trees after four to six weeks following 

spray application. However, Mayerhofer et al. 

(2009) showed that the use of streptomycin sprays 

can lead to detectable concentrations of 

streptomycin in apples. Streptomycin was detected 
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voted upon by the full Board. They are not final Board recommendations or NOP policy. 

Revised June 20 2013

in 20 of 41 samples from orchards that were 

treated one to three times with streptomycin 

sprays. The concentration of streptomycin was 

highest in the apple cores and skin and ranged 

from 1.9 to 18.4 μg/kg (equivalent to 0.0019 to 

0.0184 ppm, well below the EPA’s established 

tolerance of 0.25 ppm). (TR lines 238-244)

7. Would the use of the substance be 

harmful to human health or the 

environment? [§6517 (c)(1)(A)(i); 

§6517 (c)(2)(A)(i); §6518(m)(4)]

X X The TRED for streptomycin concluded that “there 

is reasonable certainty that no harm to any 

population subgroup will result from exposure to 

streptomycin (EPA, 2006b). (March 8, 2011 TR 

lines 438 – 439) Also, in the TR lines 441-444 

states that “Current tolerances (maximum residue 

limits) for streptomycin on or in apples and pears is 

0.25ppm. Assuming that the maximum amount of 

streptomycin residues are present in all types of 

food which may contain residues, EPA determined 

that chronic aggregate dietary exposure from 

streptomycin residues in food and water is not 

considered to be a human health concern (EPA, 

2006a).

Bacterial resistance to streptomycin as a result of 

pesticidal use has the potential to cause adverse 

public health consequences if human bacterial 

pathogens are present in orchards and develop 

resistance or if non-pathogenic bacteria in 

orchards develop resistance and later transfer the 

resistance to human bacterial pathogens. EPA’s 

assessment concluded that “the possibility of 

antibiotic resistance resulting in adverse human 

health consequences was of medium concern 

following occupational application and was of high 

concern following application by residential users” 

(EPA, 2006a, pg. 3). (TR lines 645-650) 

Streptomycin remains important in modern 

medicine, and an increase in streptomycinresistant bacteria in the environment and in 

humans may lead to adverse human health 

consequences. Streptomycin is used today in 

medicine in combination therapy to treat 

tuberculosis (due to increasing resistance to other 

anti-tubercular drugs) and enterococcal 

endocarditis (when there is resistance to 

gentamicin). It is also used to treat the plague and 

tularemia. (TR lines 634-638)

See also question #5.

Streptomycin is toxic to algae (Qian et al., 2012) 

and therefore the EPA requires a warning on any 

streptomycin label include a warning not to apply 

directly to water or in areas where surface water is 

present, and to not contaminate water during 

cleaning of equipment or disposal of wastes. TR 

lines 414-415 states that the RED for streptomycin 

concluded that agricultural streptomycin products, 

labeled and used according to EPA regulations, 

will not pose unreasonable risks or adverse effects 

to the environment (EPA 1992). There is an EPA 

registration review of streptomycin underway that 

is scheduled to be completed in 2014.
This is a proposal by a Subcommittee of the National Organic Standards Board (NOSB). Proposals are posted for public comment and then may be 

voted upon by the full Board. They are not final Board recommendations or NOP policy. 

Revised June 20 2013

8. Are there adverse biological and 

chemical interactions in the agroecosystem, including biodiversity? 

[§6518(m)(5)]

X Toxic to bacteria and algae. See question #7. The 

ammonium-Nitrogen concentration was 

significantly increased following application of 

streptomycin, possibly indicating that nitrifying 

bacteria were susceptible to this bactericide. This 

study also found that application of streptomycin at 

a rate of 3 mg/g soil caused a continuing reduction 

in the total bacterial population which lasted longer 

than the study (22 days). Streptomycin applied at 3 

mg/g soil also reduced active hyphae only on the 

first day following application. A broad-spectrum 

antibiotic like streptomycin would be expected to 

inhibit the nitrification process in soil. The presence 

of streptomycin in three different types of soils 

affected the ecological balance in the soil, causing 

the elimination of some bacterial populations. The 

eliminated species were described as beneficial 

bacteria involved in various metabolic processes, 

mineralization of organic compounds, degradation 

of toxic compounds, or creating soil structure. This 

study also isolated from the soils many strains of 

bacteria demonstrating resistance to streptomycin, 

including opportunistic pathogens of humans 

and/or animals. (2011 TR lines 377-378, 379-382, 

386-387, 389-391, 395-398)

Based on the limited data available, it is still 

unclear if the use of streptomycin for control of fire 

blight has significant negative effects on 

interactions in the agro-ecosystem, including soil 

organisms. There are no studies available in the 

field and the studies in the laboratory with soil 

bacterial populations appear to be contradictory. 

(TR lines 404-407)

9. Are there detrimental physiological 

effects on soil organisms, crops, or 

livestock? [§6518(m)(5)]

X Toxic to algae. (TR line 347) Algae are present in 

most of the soils where moisture and sunlight are 

available, mostly blue-green (Cyanophyta) and 

green (Chlorophyta). Soil algae are important in 

maintaining fertility, building soil organic matter, 

building soil structure, increasing water holding 

capacity, and aerating soils.31
This is a proposal by a Subcommittee of the National Organic Standards Board (NOSB). Proposals are posted for public comment and then may be 

voted upon by the full Board. They are not final Board recommendations or NOP policy. 

Revised June 20 2013

NOSB Evaluation Criteria for Substances Added To the National List

Crops or Livestock

Category 2. Is the Substance Essential for Organic Production? Substance: Streptomycin

Question Yes No N/A Comments/Documentation (TAP; 

petition; regulatory agency; other)

1. Is the substance agricultural? 

[§6502(1)]

X

2. Is the substance formulated or 

manufactured by a chemical 

process? [§6502(21)]

X

3. Is the substance formulated or 

manufactured by a process that 

chemically changes a substance 

extracted from naturally occurring 

plant, animal, or mineral sources? 

[§6502(21)]

X Streptomycin is a naturally occurring 

compound which is produced by the soil 

bacterium Streptomyces griseus.

Agricultural streptomycin is produced on a 

large scale by aerobic fermentation of 

Streptomyces griseus followed by isolation 

and purification by ion exchange (HSDB, 

2002; EPA, 1992) March 8, 2011 TR lines 

172-174. Also, TR lines 199-200 states that 

Streptomycin is produced through a 

naturally occurring process (aerobic 

fermentation), but the processes used to 

isolate and purify the substance are not 

naturally occurring. The forms of 

streptomycin currently on the National List 

as approved are listed as synthetic 

substances.

4. Is the substance created by 

naturally occurring biological 

processes? [§6502(21)]

X X Streptomycin is a naturally occurring 

compound which is produced by the soil 

bacterium Streptomyces griseus. 

Commercially, streptomycin is produced 

through a naturally occurring process 

(aerobic fermentation), but the processes 

used to isolate and purify the substance are 

not naturally occurring. (TR lines 199-201)

5. Is there a natural source of the 

substance? [§ 205.600(b)(1)]

X

6. Is there an organic substitute? 

[§205.600(b)(1)]

X

7. Is there a wholly natural substitute 

product?

[§6517(c)(1)(A)(ii)]

X X There are several biological control agents 

(such as bacteria or yeast) that are used to 

try to outcompete the fire blight pathogen 

where it occurs on the blossom. These 

materials are used for fire blight 

suppression. Two strains of beneficial 

bacterium, Pantoea agglomerans, are: 

Bloomtime Biological and Blight Ban C9-1. 

The bacterium Pseudomonas fluorescens 

A506 is marketed as Blight Ban A506. There 

are two strains of yeast Aureobasidium 
This is a proposal by a Subcommittee of the National Organic Standards Board (NOSB). Proposals are posted for public comment and then may be 

voted upon by the full Board. They are not final Board recommendations or NOP policy. 

Revised June 20 2013

pullulans that are used to make up the 

product Blossom Protect (Bio-ferm, 

Germany) which has recently been 

introduced into the market to help in 

controlling fire blight. TR 2011 lines 468-

486. In this same TR, Blight Ban A506 is 

rated as being poor to fair for effectiveness, 

lines 493-505 (Johnson et al.,2009) in 

inoculated trials and slightly better in field 

trials (Johnson 2010). Johnson further states 

that Bloomtime and Blight Ban C9-1 both 

performed slightly better with about 50% 

reduction in disease incidence observed in 

the inoculated field tests. He rates 

Bloomtime Biological as poor to good and 

the effectiveness of Serenade Max and 

Blossom Protect as fair to good for 

effectiveness for fire blight suppression. By 

comparison, the antibiotic treatment 

oxytetracycline is described as fair to very 

good, and treatment with streptomycin is 

poor to excellent (the poor rating is due to 

widespread pathogen resistance to 

streptomycin within the western states). (TR 

lines 493-507) Disease control was more 

consistent in field trials conducted with 

compatible mixtures of antagonistic 

organisms than with single strains –up to 68 

and 71% disease reduction on average, 

compared to 39% and 81% on average, for 

oxytetracycline and streptomycin, 

respectively. (TR lines 517-532) In 

Germany, treatment with Blossom Protect 

resulted in an average efficiency of 82% 

reduction in fire blight incidence (results 

from six different trials). (TR lines 547-548) 

Johnson (2010) reports that he and his 

colleagues evaluated Blossom Protect in an 

inoculated fire blight trial in 2008 (also using 

four applications during bloom). They found 

this product to be nearly as effective as 

streptomycin (Agri-Mycin) in an orchard with 

high disease pressure. (TR lines 552-555) A 

large amount of public comment received in 

written form to FR Docket AMS-NOP-12-

0070 and verbally at the Spring 2013 

meeting indicated that the above "substitute 

products" did not work well in certain regions 

or agricultural systems and therefore were 

not true substitutes.
This is a proposal by a Subcommittee of the National Organic Standards Board (NOSB). Proposals are posted for public comment and then may be 

voted upon by the full Board. They are not final Board recommendations or NOP policy. 

Revised June 20 2013

8. Are there any alternative 

substances? 

[§6518(m)(6)]

X Besides the biologicals, there are 

alternative substances that are listed as 

having some control of fire blight and of 

these oxytetracycline is by far the best 

alternative substance. Other materials listed 

are various copper mixtures (a couple of 

new products currently being looked at by 

researchers), lime-sulfur, and Peracetic acid 

(which is as a disinfectant and not as a 

spray replacement material).

9. Are there other practices that would 

make the substance unnecessary? 

[§6518(m)(6)]

X X No one practice can eliminate fire blight, 

including the use of antibiotics. There are 

practices that can help in reducing fire blight 

potential in an orchard as part of a systems 

approach. Some of these would include 

using fire blight prediction models to assist 

in proper timing of materials applications, 

monitoring and removal of infected plant 

tissue, planting of resistant root stocks (this 

would only protect the root system and not 

the fruit producing portion of the tree), 

ground cover and water management to 

help reduce humidity levels within an 

orchard, and also planting of more fire blight 

resistant cultivars. (TR lines 601-617, 671-

701)
This is a proposal by a Subcommittee of the National Organic Standards Board (NOSB). Proposals are posted for public comment and then may be 

voted upon by the full Board. They are not final Board recommendations or NOP policy. 

Revised June 20 2013

NOSB Evaluation Criteria for Substances Added To the National List

Crops or Livestock

Category 3. Is the substance compatible with organic production practices? Substance: 

Streptomycin 

Question Yes No N/A Comments/Documentation (TAP; 

petition; regulatory agency; other)

1. Is the substance consistent with organic 

farming and handling? 

[§6517(c)(1)(A)(iii); 6517(c)(2)(A)(ii)]

X X It is currently included on the National List 

of Allowed and Prohibited Substances, as 

a synthetic substance allowed in organic 

crop production for fire blight control in 

apples and pears only [7 CFR 205.601 

(i)(11)] as previously /currently 

approved by the NOSB and implemented 

into policy by the NOP.

Contrary to consumer expectations. 

Inconsistent with prohibition on antibiotics 

in livestock. Inconsistent with European 

requirements.

2. Is the substance compatible with a 

system of sustainable agriculture? 

[§6518(m)(7)]

X X If it is used as part of an organic systems 

plan in a rotational manner, to enhance 

resistance management in an effort to 

minimize the potential for resistance to 

fire blight to develop.

Increases likelihood of antibiotic 

resistance in pathogenic organisms. It is 

not sustainable because the fire blight 

organism will develop resistance.

3. If used in livestock feed or pet food, Is 

the nutritional quality of the food 

maintained with the substance? 

[§205.600(b)(3)]

X

4. If used in livestock feed or pet food, Is 

the primary use as a preservative? 

[§205.600(b)(4)]

X

5. If used in livestock feed or pet food, Is 

the primary use to recreate or improve 

flavors, colors, textures, or nutritive value 

lost in processing (except when required 

by law)? [§205.600(b)(4)]

X

6. Is the substance used in production, and 

does it contain an active synthetic 

ingredient in the following categories: 

[§6517(c)(1)(B)(i);

copper and sulfur compounds

X

toxins derived from bacteria X

pheromones, soaps, horticultural oils, 

fish emulsions, treated seed, vitamins 

and minerals

X

livestock parasiticides and medicines X
This is a proposal by a Subcommittee of the National Organic Standards Board (NOSB). Proposals are posted for public comment and then may be 

voted upon by the full Board. They are not final Board recommendations or NOP policy. 

Revised June 20 2013

production aids including netting, tree 

wraps and seals, insect traps, sticky 

barriers, row covers, and equipment 

cleansers

X

 1 Stockwell, V.O., and Duffy, B., 2012. Use of antibiotics in plant agriculture. Rev. Sci. Tech. Off. Int. Epiz., 31:199-210.

2 As reported in Ostenson, H.T. 2010. Organic pome and cherry production and marketing issues: Past, present and 

future. Acta Hort. (ISHS) 873:137-144, and presented to IFOAM, “Over the last ten years, the Hartman Group (Bellevue, 

Washington, USA) has studied changes in consumer attitudes, backgrounds, and buying characteristics related to the 

organic market. The Hartman Group surveyed about two thousand household consumers across four regions of the USA. 

They found that the ‘traditional’ properties suggested by ‘organic’ were no longer the same properties held by the new 

organic consumer. The survey indicated that traditional properties such as ‘locally-grown,’ Fair Trade, ‘tastes better,’ and 

sustainable production ranked at the bottom. The new organic consumers made it clear that they want, plain and simple, a 

product centered around the ‘absence of all health concerns,’ and the absence of pesticides, growth hormones, GMO’s, 

antibiotics, and BSE.”

3 McGhee, G. C., Guasco, J., Bellomo, L. M., Blumer-Schuette, S. E., Shane, W. W., Irish-Brown, A., and Sundin, G. W.,

2011. Genetic analysis of streptomycin-resistant (SmR) strains of Erwinia amylovora suggests that dissemination of two 

genotypes is responsible for the current distribution of SmR E. amylovora in Michigan. Phytopathology 101:182- 191.

4 Russo, N. L., Burr, T. J., Breth, D. I., and Aldwinckle, H. S., 2008. Isolation of streptomycin resistant isolates of Erwinia 

amylovora in New York. Plant Dis. 92:714-718.

5 Claudia Nischwitz, Christine Dhiman, 2012. Streptomycin resistance of Erwinia amylovora, causal agent of fire blight.

Utah State University Extension and Utah Plant Pest Diagnostic Laboratory, PLP-018.

6 McGhee, G. C., Guasco, J., Bellomo, L. M., Blumer-Schuette, S. E., Shane, W. W., Irish-Brown, A., and Sundin, G. W. 

2011. Genetic analysis of streptomycin-resistant (SmR) strains of Erwinia amylovora suggests that dissemination of two 

genotypes is responsible for the current distribution of SmR E. amylovora in Michigan. Phytopathology 101:182- 191. 7 Russo, N. L., Burr, T. J., Breth, D. I., and Aldwinckle, H. S., 2008. Isolation of streptomycin resistant isolates of Erwinia 

amylovora in New York. Plant Dis. 92:714-718.

8

Instead, these growers rely on a number of other practices, allowing them to avoid fire blight damage to susceptible 

varieties. Balancing nutrients and avoiding over-application of nitrogen fertilizers, especially on susceptible varieties of 

apples or pears; avoidance of over-pruning in the dormant season; use of pre-bloom foliar nutrient sprays even though 

there is no foliage; use of copper materials on the trees between delayed dormant and tight cluster sages as preventive 

measures against overwintering FB; use of lime sulfur during bloom to thin apples; and, use of Serenade MAX (in the 

future, perhaps Blossom Protect) post-bloom and at petal-fall, with good spray coverage. (With some differences for 

pears.)

9 In response, the following is suggested: Increase species diversity; decrease tree density; use resistant cultivars and 

rootstocks; plant a variety of cultivars on a variety of rootstocks.

10 Yashiro, E & McManus, P. 2012 Effect of streptomycin treatment on bacterial community structure in the apple 

phyllosphere. PLoS ONE 7(5): e37131. doi:10.1371/journal.pone.0037131 11 WHO, 2009. Critically Important Antimicrobials for Human Medicine, 

http://www.who.int/foodsafety/foodborne_disease/CIA_2nd_rev_2009.pdf See Table 1.

12 Streptomycin TR, 2011. Lines 423-431.

13 American Academy of Microbiology, 2009. Antibiotic Resistance: An Ecological Perspective on an Old Problem. 

http://academy.asm.org/images/stories/documents/antibioticresistance.pdf (pp.1-5, 10.) 14 American Academy of Microbiology, 2009. (p.8.) 15 Streptomycin TR, 2011. Lines 632-633. American Academy of Microbiology, 2009. (p.2.) 16 Gullberg E, Cao S, Berg OG, Ilbäck C, Sandegren L, et al., 2011. Selection of Resistant Bacteria at Very Low Antibiotic 

Concentrations. PLoS Pathog 7(7): 1-9.

17 McGhee, G. C., Guasco, J., Bellomo, L. M., Blumer-Schuette, S. E., Shane, W. W., Irish-Brown, A., and Sundin, G. W. 

2011. Genetic analysis of streptomycin-resistant (SmR) strains of Erwinia amylovora suggests that dissemination of two 

genotypes is responsible for the current distribution of SmR E. amylovora in Michigan. Phytopathology 101:182-191. Alan 

L. Jones and Elise L. Schnabel, 2000. The Development of Streptomycin-resistant Strains of Erwinia amylovora, in J.L. 

Vanneste (ed.), Fire Blight The Disease and its Causative Agent, Erwinia amylovora, CAB International, UK. Pp. 235-254.

18 S. Tolba et al., 2002. Distribution of streptomycin resistance and biosynthesis genes in streptomycetes recovered from 

different soil sites. FEMS Microbiology Ecology 42: 269-276

19 Egan, S., Wiener, P., Kalli¢das, D. and Wellington, E.M.H. (2001) Phylogeny of Streptomyces species and evidence of 

horizontal transfer of entire and partial antibiotic gene clusters. Antonie Van Leeuwenhoek 79, 127-133. Wiener, P., 
This is a proposal by a Subcommittee of the National Organic Standards Board (NOSB). Proposals are posted for public comment and then may be 

voted upon by the full Board. They are not final Board recommendations or NOP policy. 

Revised June 20 2013

 Egan, S. and Wellington, E.M.H. (1998) Evidence of transfer of antibiotic-resistance genes in soil populations of 

streptomycetes. Mol. Ecol. 7, 1205-1216.

20 George W. Sundin, Dave E. Monks, Carol L. Bender, 1995. Distribution of the streptomycin-resistance transposon 

Tn5393 among phylloplane and soil bacteria from managed agricultural habitats. Canadian Journal of Microbiology, 41(9): 

792-799.

21 Yashiro E, McManus PS, 2012. Effect of Streptomycin Treatment on Bacterial Community Structure in the Apple 

Phyllosphere. PLoS ONE 7(5): e37131

22 McGhee, G. C., Guasco, J., Bellomo, L. M., Blumer-Schuette, S. E., Shane, W. W., Irish-Brown, A., and Sundin, G. W. 

2011. Genetic analysis of streptomycin-resistant (SmR) strains of Erwinia amylovora suggests that dissemination of two 

genotypes is responsible for the current distribution of SmR E. amylovora in Michigan. Phytopathology 101:182- 191.

23 Sundin, G. W. 2002. Distinct recent lineages of the strA-strB streptomycin-resistance genes in clinical and 

environmental bacteria. Curr.Microbiol. 45:63-69.

24 GW Sundin and CL Bender, 1996. Dissemination of the strA-strB streptomycin-resistance genes among commensal 

and pathogenic bacteria from humans, animals, and plants, Molecular Ecology 5, 133-143

25 See for example, Cristina Pezzella, Antonia Ricci, Elisabetta DiGiannatale, Ida Luzzi, and Alessandra Carattoli, 2004. 

Tetracycline and Streptomycin Resistance Genes, Transposons, and Plasmids in Salmonella enterica Isolates from 

Animals in Italy. Antimicrobial Agents and Chemotherapy, 48 (3): 903–908. Alexandre Scherer, Hans-Rudolf Vogt, Edy M. 

Vilei, Joachim Frey, and Vincent Perreten, 2013. Enhanced antibiotic multi-resistance in nasal and faecal bacteria after 

agricultural use of streptomycin, Environmental Microbiology 15(1), 297–304. (“This study shows that the application of 

low concentrations of streptomycin on grass, as occurs during the spraying of orchards, selects for multidrug-resistant 

nasal and enteric bacterial flora, including extended-spectrum beta-lactamase-producing E. coli.”) Foster, G. C., McGhee, 

G. C., Jones, A. L., and Sundin, G. W. 2004. Nucleotide sequences, genetic organization, and distribution of pEU30 and 

pEL60 from Erwinia amylovora. Appl. Environ. Microbiol. 70:7539-7544.

26 WHO, 2009. Critically Important Antimicrobials for Human Medicine, 

http://www.who.int/foodsafety/foodborne_disease/CIA_2nd_rev_2009.pdf See Table 1. Tuberculosis is rapidly developing 

resistance to all known antimicrobials. Phillip Trollip, 2013. Emergence and Spread of Extensively and Totally DrugResistant Tuberculosis, South Africa. Emerging Infectious Diseases, 19 (3): 449-455 www.cdc.gov/eid 27 http://www.drugs.com/pro/streptomycin.html 28 Jose Luis Martinez, 2009. Environmental pollution by antibiotics and by antibiotic resistance determinants. 

Environmental Pollution 157: 2893–2902.

29 See, for example, the following articles. C.-S. Chiou and A. L. Jones, 1993. Nucleotide Sequence Analysis of a 

Transposon (Tn5393) Carrying Streptomycin Resistance Genes in Erwinia amylovora and Other Gram-Negative Bacteria. 

Journal of Bacteriology, Vol. 175, (3): 732-740. GW Sundin and CL Bender, 1996. Dissemination of the strA-strB 

streptomycin-resistance genes among commensal and pathogenic bacteria from humans, animals, and plants, Molecular 

Ecology 5, 133-143. McGhee, G. C., and Sundin, G. W. 2011. Evaluation of kasugamycin for fire blight management, 

effect on nontarget bacteria, and assessment of kasugamycin resistance potential in Erwinia amylovora. Phytopathology 

101:192-204. Cristina Pezzella, Antonia Ricci, Elisabetta DiGiannatale, Ida Luzzi, and Alessandra Carattoli, 2004. 

Tetracycline and Streptomycin Resistance Genes, Transposons, and Plasmids in Salmonella enterica Isolates from 

Animals in Italy. Antimicrobial Agents and Chemotherapy, 48 (3): 903–908. Alexandre Scherer, Hans-Rudolf Vogt, Edy M. 

Vilei, Joachim Frey, and Vincent Perreten, 2013. Enhanced antibiotic multi-resistance in nasal and faecal bacteria after 

agricultural use of streptomycin, Environmental Microbiology 15(1), 297–304.

30 WHO, 2009. Critically Important Antimicrobials for Human Medicine, 

http://www.who.int/foodsafety/foodborne_disease/CIA_2nd_rev_2009.pdf See Table 1. 

31 “Soil microorganism—algae” My Agriculture Information Bank http://agriinfo.in/?page=topic&superid=5&topicid=150

Zancan, S., Trevisan, R., & Paoletti, M. G. (2006). Soil algae composition under different agro-ecosystems in NorthEastern Italy. Agriculture, ecosystems & environment, 112(1), 1-12.