FORMAL RECOMMENDATION BY THE

NATIONAL ORGANIC STANDARDS BOARD (NOSB) 

TO THE NATIONAL ORGANIC PROGRAM (NOP) 

Date: _____6-3-06___________________

Subject: Sunset Review - 205.601 Synthetic substances allowed for use in organic crop 

production 

Chair: Kevin O’Rell 

Recommendation

The NOSB hereby recommends to the NOP the following: 

Rulemaking Action: _XXXXXX_ 

Guidance Statement: ________ 

Other: ________ 

Statement of the Recommendation (including Recount of Vote):

See attached Recommendation for Renewal of Chlorinated Materials as Synthetic substances 

allowed for use in organic crop production on 205.601, category use (a) as algicides, 

disinfectants, and sanitizers. 

NOSB Vote: 

Moved: Gerald Davis Second: Nancy Ostiguy 

Yes – 10 

No – 2 

Abstain – 0 

Absent – 2 

Rationale Supporting Recommendation (including consistency with OFPA and NOP):

NOSB Sunset Material Vote 

Response by the NOP:
NOSB- Crops Committee 

Chlorinated Materials - Sunset Recommendation 

Final NOSB Recommendation 4/20/2006

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

II. Category Use 

(a). As algicides, disinfectants and sanitizers 

III. Committee Summary: Many public comments were received by the NOP 

supporting the continued allowance of the use of the chlorine materials (calcium 

hypochlorite, sodium hypochlorite, and chlorine dioxide) in this category. The most 

common reason given for the continued use was for food safety concerns over the 

potential contamination of organic produce by food borne pathogens. A big concern 

is that the negative public reaction to potential outbreaks of illness associated with 

organically produced food would be catastrophic to the industry. Compliance with FDA 

and other health regulatory agency regulations and guidelines was another common 

concern. 

Some comments expressed concern about the application of chlorine materials to organic 

product in excess of the NOP standard listed in the Rule. These comments stated that 

chlorine concentrations well in excess of the NOP standard are used in some instances 

with the assumption that the material would be degraded or diluted at some later point in 

the handling process of the crop or at least before the produce reached the consumer. Two 

of these comments (from a vegetable sprout producer and a consumer association) 

specifically stated that the residual chlorine levels in solution must not exceed the NOP 

Rule guideline at the point at which the treatment solution is drained from the food being 

treated. The crops committee agrees with the comments that more specific guidelines for 

the use of chlorine materials in organic crop applications are needed, but the committee 

also acknowledges that such a recommendation to add further addenda to the regulation 

is not the purview of this sunset document. 

One comment (from a PAA supplier) proposed peracetic acid (PAA), a hydrogen 

peroxide/acetic acid combination, as a safer alternative disinfectant to chlorine. This 

comment also acknowledged that PAA is currently not an allowed replacement for some 

of the chlorine application uses. 

One comment objected to the use of any synthetics in organic crop production. 

Review of the current Technical Evaluation Report supplied to the NOP shows that 

calcium and sodium hypochlorite, and chlorine dioxide are all synthetic materials not 

produced from naturally occurring sources or processes. 

The report states that no information is available from EPA or FDA to suggest that 

environmental contamination results from the proper manufacture, use, or disposal 

of calcium or sodium hypochlorite. Contamination from misuse or improper disposal is 

possible, although these materials are broken down by sunlight to compounds commonly 
found in air. Release into soil has the potential to release hypochlorite ions which can 

react with soil organic matter to form carcinogenic trihalomethane compounds (THMs). 

Sodium and calcium hypochlorite are toxic to freshwater fish and invertebrates. 

Discharges of hypochlorite wastes from facilities are regulated through issuance of sitespecific wastewater discharge permits intended to ensure that no significant adverse 

effects on such wildlife occur. The effects on wildlife from wastewater discharges should 

be minimized by the adherence to the Safe Drinking Water Act limit of 4mg/L. The 

production of trihalomethanes in the reaction with organic matter in soil or water would 

also be minimized if the 4 mg/L guideline is followed. 

When used as an irrigation system cleanser within the allowed limits, calcium and 

sodium hypochlorite, and chlorine dioxide would not be expected to have any detrimental 

effects on soil organisms, crops, or livestock. If misused, sodium hypochlorite may 

possibly raise soil pH, add sodium, and kill beneficial microorganisms. 

The breakdown materials of calcium and sodium hypochlorite are hypochlorous acid 

and hypochlorite ions which are highly toxic and corrosive. EPA has placed them in 

Toxicity Category I (indicating the highest degree of acute toxicity) for oral, dermal, 

eye, and inhalation effects. As stated above, hypochlorite ion, when mixed with organic 

materials (e.g. humates in soil), forms trihalomethanes(THMs), which are carcinogenic. 

There is a slightly increased risk of developing bladder or colorectal cancer over a 

lifetime if THMs are ingested in excess of the current drinking water limits over an 

extended period of time. The EPA has ruled that the concentrations of THMs in water 

should be less than 80 parts per billion. Calcium and sodium hypochlorite are highly 

caustic and are a concern for occupational exposures to concentrated solutions 

(ASTDR,2002). 

Possible toxic effects of chlorine dioxide are that it is a severe respiratory and eye irritant. 

The reaction products of chlorine dioxide are chlorites and chlorates. The toxic action of 

ingestion of chlorite is primarily in the form of oxidative damage to red blood cells and 

also neurodevelopmental effects. An inhalation study showed vascular congestion and 

lung damage effects(EPA 2000). 

Chlorine dioxide, sodium hypochlorite, and calcium hypochlorite are not persistent in the 

environment. Potential human health effects due to these materials occur dermally or by 

inhalation. Dermal symptoms range from mild irritation to blistered skin depending on 

the concentration of the solutions. Inhalation symptoms include nasal irritation, sore 

throat, coughing, respiratory distress, and lung congestion. 

Citric acid or other acids (such as acetic, ascorbic) were mentioned as wholly natural 

substitute products that could be substituted for the chlorine materials as irrigation line 

cleaners and equipment sanitizers. No information on the effectiveness of these materials 

in crop wash water was offered in the report. One commentator offered an example of 

acetic acid use in the meat industry as a carcass wash for surface sanitation. In this 

application wash water is amended to pH 3 to attain surface sanitation. Extrapolating this 

information to crop wash water, maintaining this low of a pH would take substantial and 

continual additions of acid, which would be corrosive to the handling equipment, the 

workers in the operation, and the crop as well in many cases (Envirotech). 
Other allowed substitute materials listed in the Technical Evaluation Report include 

hydrogen peroxide, ozone, peracetic acid, various alcohols, copper sulfate, and soap 

based algicides. Steam sterilization and UV radiation were mentioned as alternative 

practices that might make the use of chlorine materials unnecessary. Of these materials, 

the peracetic acid appears to hold the most promise as a safer alternative to chlorine in 

crop wash water applications. It requires at least a 50 fold lower concentration than 

hydrogen peroxide for sanitation efficacy in crop wash water, which would eliminate the 

bleaching(oxidizer) effect problem associated with hydrogen peroxide(EnviroTech). 

Peracetic acid was recommended for approval for this purpose by a previous NOSB, but 

has not cleared the NOP rulemaking process as yet. Ozone, as mentioned by the Report, 

has a strong tendency to off-gas from wash water and causes serious headaches in 

workers exposed to it. UV light from special lamps has been shown to be effective 

in some limited applications. 

Due to overriding food safety and regulatory issues, the Crops Committee recommends 

the renewal of these chlorine materials. 

 

IV. Committee Recommendation: 

Recommendations based upon comments received- 205.601(a) 

The Crops Committee recommends the renewal of the following materials to the use 

category: 

(2) Chlorine materials- Except, that residual chlorine materials in the water shall 

not exceed the maximum residual disinfectant limit under the Safe Drinking Water 

Act. 

(i) Calcium hypochlorite 

(ii) Sodium hypochlorite 

(iii) Chlorine dioxide 

Moved: Jeff Moyer Second: Kevin Engelbert 

Committee vote: 3-0 2 absent (Delgado, Ostiguy) 

NOSB vote: 

Moved: Gerald Davis Second: Nancy Ostiguy 

Yes – 10 

No – 2 

Abstain – 0 

Absent – 2