National Organic Standards Board

Crops Committee

2013 Sunset Proposed Recommendation

Calcium chloride

October 7, 2011

List: §205.602 Non-Synthetic substances prohibited for use in organic crop production.

(c) Calcium chloride, brine process is natural and prohibited for use except as a foliar 

spray to treat a physiological disorder associated with calcium uptake.

Committee Summary:

Calcium chloride is currently on the National List of non-synthetic materials prohibited for crop 

production with the following annotation: ...“brine process is natural and prohibited for use 

except as a foliar spray to treat a physiological disorder associated with calcium uptake.” 

In considering crop materials as part of the sunset process, the Crops Committee reviews the 

previous NOSB work pertaining to the material, as well as any new information that has 

become available since the original board decision.

An updated Technical Report (TR) on this material was requested, but not received prior to 

consideration. Review was made of the 2001 TR, as well as the other steps taken, including 

the 2007 NOSB Sunset Recommendation (as adopted). 

Brine process Calcium chloride would be classified as a mined substance of high solubility as 

mentioned in §205.203(d)(3), and as such its use is subject to the conditions established on 

the National List of non-synthetic materials prohibited for crop production. 

The foundational principle for placing high solubility materials such as Calcium chloride, 

Potassium chloride, etc. on a prohibited non-synthetic materials list is spelled out in 

§205.203(d) – Soil fertility and crop nutrient management practice standard; “A producer may 

manage crop nutrients...in a manner that does not contribute to contamination of crops, soil, or 

water by plant nutrients...” The current Crops Committee respects the intent of the earlier 

NOSB to annotate the prohibition on this material in such a way as to accomplish these 

nutrient management goals. 

Public comment on the previously considered annotation for Calcium chloride expressed 

concerns regarding;

1) application rates applied with the proper methods in irrigation water which can supply 

calcium nutrient without significant soil or water contamination and with less salt burn to the 

crop foliage, particularly in sensitive vegetable and greenhouse crops, 

2) the fact that chloride is an essential plant nutrient and can be deficient in some situations. In 

addition, some irrigation waters have almost no dissolved minerals (including chlorides and 

calcium), which can cause poor soil infiltration rates. Small amounts of calcium chloride added 

to irrigation water would be a very appropriate management choice to provide nutrients and 

improve the infiltration rate, and,
2013 Sunset Recommendation Calcium Chloride

September 6, 2011

Page 2 of 2

3) limitations on calcium chloride use are much more restrictive than the other mined natural 

chloride materials allowed in organic farming. The Potassium chloride annotation reads,

“unless derived from a mined source and applied in a manner that minimizes chloride 

accumulation in the soil”. Magnesium and Sodium chloride, although high solubility mined 

substances, are not on the prohibited non-synthetic list at all. Some consistency is needed in 

how these materials are listed. Public comment suggested capturing the intent of the 

regulation in §205.203(d), and bringing consistency within §205.602 with the following 

annotation language:

Generic chloride – unless derived from a non-synthetic mined and/or brined source, and 

applied in a manner that minimizes chloride accumulation in soils, sub-soils, surface waters or 

groundwater.

It is worth recognizing that these comments still have merit, and that petitions are a viable 

strategy for change. Yet, the Crops Committee acknowledges that annotations cannot be 

changed during the sunset review process, and can only be changed through the petition 

process.

Committee Recommendation

Considering the fact that potential overuse of this natural substance, as well as resultant 

subsoil, surface water and ground water contamination warrant continued limitation of use, the 

recommendation is:

To retain calcium chloride on §205.602(c) Non-synthetic substances prohibited for use in 

organic crop production, with (c) Calcium chloride, brine process is natural and prohibited for 

use except as a foliar spray to treat a physiological disorder associated with calcium uptake.

Committee Vote

Motion: Colehour Bondera Second: Barry Flamm

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