Updated June 17, 2010 

Formal Recommendation by the 

National Organic Standards Board (NOSB) 

to the National Organic Program (NOP)

Date: April 29, 2011

Subject: 2012 Sunset Review of Sulfur Dioxide listed on §205.601 

Synthetic substances allowed for use in organic crop 

production: (g) As rodenticides (1) Sulfur dioxide—underground 

rodent control only (smoke bombs)

Chair: Tracy Miedema

 

 

The NOSB hereby recommends to the NOP the following: 

Rulemaking Action X

Guidance Statement 

Other 

Statement of the Recommendation (Including Recount of Vote): 

Motion was to relist sulfur dioxide—underground rodent control only (smoke 

bombs) on § 205.601(g)(1). The Motion was defeated five no and nine yes as 

two-thirds majority was required to relist. The recommendation is therefore to 

not relist sulfur dioxide on the National List Synthetic Substances allowed for 

use in organic crop production.

 

Rationale Supporting Recommendation (including consistency with 

OFPA and NOP): 

The Crops Committee requested a new TR for sulfur dioxide used in this 

application specifically—as rodent control in smoke bomb. The new TR pointed 

out “The U.S. EPA has not registered sulfur dioxide for use as a rodenticide. 

However, U.S. EPA has registered rodent control smoke bombs with the active 

ingredients sulfur, charcoal carbon, and sodium nitrate or potassium nitrate 

(saltpeter).” (TR Sulfur Dioxide January 14, 2011 lines 139-141). The TR also 

states “Ignition of the smoke bomb generates a mixture of gases that may 

include sulfur dioxide” (ibid, line 148). Sulfur dioxide does not appear to exist 

as the only active ingredient in commercially produced smoke bombs used as 

rodenticides. The crops committee concluded that it is possible that the wrong 

active ingredient for smoke bombs used as rodenticides was listed historically 

and is recommending that sulfur dioxide for use in smoke bombs for 

underground control of rodents be taken off the list.
Updated June 17, 2010 

The majority of public comments were in support of keeping this on the list as 

sulfur dioxide generated by smoke bombs are allowed by some certifiers as rodent 

control and is considered an important tool. There was one comment in favor of 

letting it drop off the list. It was explained that certifiers either look at the individual 

components of smoke bombs before they are exploded as the active ingredients; 

or the sulfur dioxide that results from the explosion as the active ingredient. 

Certifiers not allowing smoke bombs base this determination on the requirement 

for ignition materials to cause the explosion to make the smoke that have not been 

reviewed and are not on the National List. Discussion amongst Board members 

included alternatives available on the National List for rodent control and the 

situations in which they can be used, concerns about harm to non-target species, 

concerns about removing this method of rodent control from the farmers’ 

toolboxes, and general discussion of how we use new information generated by 

new TR’s and how we look at formulated materials. 

Committee Vote:

Moved: John Foster Second: Tina Ellor

Yes: 9 No: 5 Abstain: 0 Absent: 0 Recusal: 0
National Organic Standards Board 

Crops Committee 

2012 Sunset Proposed Recommendation 

Sulfur Dioxide 

April 29, 2011 

List: §205.601 Synthetic substances allowed for use in organic crop production. 

(g) As rodenticides 

(1) Sulfur dioxide—underground rodent control only (smoke bombs) 

Committee Summary 

The Crops Committee requested a new TR for sulfur dioxide used in this application 

specifically—as rodent control in smoke bomb. The new TR pointed out “The U.S. EPA has not 

registered sulfur dioxide for use as a rodenticide. However, U.S. EPA has registered rodent 

control smoke bombs with the active ingredients sulfur, charcoal carbon, and sodium nitrate or 

potassium nitrate (saltpeter).” (TR Sulfur Dioxide January 14, 2011 lines 139-141). The TR 

also states “Ignition of the smoke bomb generates a mixture of gases that may include sulfur 

dioxide” (ibid, line 148). Sulfur dioxide does not appear to exist as the only active ingredient in 

commercially produced smoke bombs used as rodenticides. The crops committee concluded 

that it is possible that the wrong active ingredient for smoke bombs used as rodenticides was 

listed historically and is recommending that sulfur dioxide for use in smoke bombs for 

underground control of rodents be taken off the list. 

Committee Recommendations 

Motion was to relist sulfur dioxide—underground rodent control only (smoke bombs) on § 

205.601(g)(1) 

Committee Vote 

Motion: To relist sulfur dioxide—underground rodent control only (smoke bombs) on § 

205.601(g)(1) 

Motion: Tina Ellor Second: Barry Flamm 

Yes: 0 No: 6 Absent: 1 Abstain: 0 Recuse: 0