National Organic Standards Board (NOSB)

Crops Subcommittee Report

Contaminated Input Plan

February 24, 2015

A Plan for Contaminated Inputs

Colehour Bondera (Jay Feldman, previous NOSB member, assisted with earlier drafts)

NOSB/Crops Subcommittee

Overview

The NOP regulations at §205.203 require organic producers to add organic materials, while avoiding 

contamination with substances prohibited in organic production (emphasis added):

§205.203 Soil fertility and crop nutrient management practice standard.

(a) The producer must select and implement tillage and cultivation practices that maintain or 

improve the physical, chemical, and biological condition of soil and minimize soil erosion. 

(b) The producer must manage crop nutrients and soil fertility through rotations, cover crops, 

and the application of plant and animal materials. 

(c) The producer must manage plant and animal materials to maintain or improve soil organic 

matter content in a manner that does not contribute to contamination of crops, soil, or water by 

plant nutrients, pathogenic organisms, heavy metals, or residues of prohibited substances. 

Animal and plant materials include: 

(1) Raw animal manure, which must be composted unless it is: 

(i) Applied to land used for a crop not intended for human consumption; 

(ii) Incorporated into the soil not less than 120 days prior to the harvest of a 

product whose edible portion has direct contact with the soil surface or soil 

particles; or 

(iii) Incorporated into the soil not less than 90 days prior to the harvest of a 

product whose edible portion does not have direct contact with the soil surface or 

soil particles; 

(2) Composted plant and animal materials produced through a process that: 

(i) Established an initial C:N ratio of between 25:1 and 40:1; and 

(ii) Maintained a temperature of between 131 °F and 170 °F for 3 days using an 

in-vessel or static aerated pile system; or 

(iii) Maintained a temperature of between 131 °F and 170 °F for 15 days using a 

windrow composting system, during which period, the materials must be turned a 

minimum of five times. 

(3) Uncomposted plant materials. 

 

Some specific impacts of concern from compost and manures derived from nonorganic operations 

include: heavy metals, antibiotic residues, residues of insecticides, herbicide residues, and residues of 

toxic chemicals that could affect soil microorganisms. The same concerns about heavy metals exist in 

some mined minerals, and in fish that may accumulate mercury or other metals. Concerns about 

pathogens often transfer over to animal by-products as well. This document and the attached 

spreadsheet describe the plan developed by the Crops Subcommittee for ensuring that inputs of 

organic matter do not result in contamination “of crops, soil, or water by plant nutrients, pathogenic 

organisms, heavy metals, or residues of prohibited substances.” 

Page 135 of 249
Our approach is to look at off-site inputs based on feedstocks/pathways. For each, ask: What 

contaminants might be present here? Which would survive currently prescribed requirements for 

composting? If there are remaining contaminants known to persist through the composting process at 

any level, is there a way to restrict the source so that those contaminants would not be present? (e.g., 

ask a farmer whether arsenic is fed to poultry.) If there are remaining contaminants, do they exceed 

unavoidable residual contamination levels from a historical, but not current use, of a toxic material? Are 

there treatments that could be applied to the compost that can eliminate those contaminants?

Where we’re going...

The subcommittee is trying to prioritize future work on this subject. The attached spreadsheet starts 

with a feedstock/pathway of concern as an approach to how to establish these priorities. For example, 

we might consider manure from a conventional farm. (Into how many separate categories does this 

need to be separated? Is poultry vs. other enough? Poultry/horse/cattle/other?)

1. What contaminants might be present?

2. Of the contaminants that might be present, which ones are likely to survive already prescribed 

treatment methods?

3. Of those that are likely to survive already prescribed treatment methods, which can be treated 

with other (easy) removal or avoidance methods?

a. Use those removal or avoidance methods.

b. If there are other contaminants, test for them. (Figure out a fair testing requirement.)

The spreadsheet consists of ten columns, with an additional column for experts in possible 

contamination and remediation for each possible input. Issues under consideration, as captured in the 

columns of the spreadsheet, include: 

1. off-farm input, 

2. source, 

3. components of interest,

4. likely or possible contaminants, 

5. ability to persist through composting process, 

6. avoidance methods, 

7. environmental fate of inputs when applied to soil,

8. loading rates,

9. efficacy of remediation, and 

10. testing methods. 

What assistance do we need? 

We need assistance identifying feedstocks/pathways and determining how to separate them into

categories that can be grouped. 

• Inputs from organic growers would be most helpful. 

• Expert agronomists, composters, scientists from testing laboratories and other fields can guide 

this effort.

We need help determining which contaminants are associated with which feedstocks/pathways. 

• For pesticides, searches of labels can identify those used on each input.1

• For fertilizers, some departments of agriculture have registries of fertilizer products that contain 

an analysis of each product, including heavy metal contaminants.2

1 Labels for a given use and use site can be found through a search at http://premier.cdms.net/webapls/ Pesticide 

recommendations can be found through state land grant universities or extension agencies. For example, 

http://content.ces.ncsu.edu/chemical-weed-control.pdf. 2

 See, for example, http://agr.wa.gov/PestFert/Fertilizers/FertDB/Product1.aspx. 

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• For livestock drugs, a veterinarian or livestock expert could identify drugs given to livestock that 

might appear in manure.

• For feed ingredients and additives, a livestock expert could help identify the range of ingredients 

and additives that might be found through wasted feed or manure residues.

We need assistance determining which contaminants can be removed by currently prescribed 

treatment methods.

• This needs to be researched for each contaminant. A lot of research has been done on the 

biodegradation of some pesticides and some drugs. Composting is frequently used for 

bioremediation, but sometimes requires additions, including humic acids or microorganisms, 

that would not ordinarily be present. Mulches would not be subject to the same conditions as 

materials for compost. 

• U.S. Composting Council can help with identifying contaminants that survive composting. Other 

experts in compost quality will also be consulted.

• Scientists have done research on uptake of antibiotics in crops from manure and degradation of 

antibiotics in manure during composting.

3

We need assistance identifying questions that can be asked to avoid contaminants that will not be 

removed by currently prescribed treatments.

• This is a question that should be posed for public comment along with the question of which offfarm inputs are used.

• The list of contaminants that would pass through ordinary treatment will help generate 

questions.

We need assistance identifying additional contamination removal methods –e.g., bacterial cultures that 

might be added to compost; fungi that might be used for mycoremediation.

• Bioremediation4

• Mycoremediation: 5 6

We need assistance identifying low-cost test methods, for example, bioassays with clear definitions of 

adverse effects. 

• A bioassay for clopyralid has been developed by Washington State University and Washington 

State Department of Ecology.7

3 Kumar K, Gupta SC, Baidoo SK, Chander Y, Rosen CJ (2005) Antibiotic uptake by plants from soil fertilized with animal 

manure. J Environ Qual 34:2082–2085. 

http://www.prepacvpm.org/wordpress/resources/_Exam_Topics_2012/2_EnvironHealthToxicology/6_Waste/AnimalAgWasteManagement/Antibiotic_Uptake_Plants.pdf Dolliver, Holly, Kumar, Kuldip, Gupta, 

Satish, Sulfamethazine Uptake by Plants from Manure-Amended Soil. JOENQ 2007. 36:1224–1230. 

https://dl.sciencesocieties.org/publications/jeq/abstracts/36/4/1224 Holly Dolliver, Satish Gupta, and Sally Noll, Antibiotic 

degradation during manure composting. . Environ. Qual. 37:1245–1253 (2008). 4 Pruden, Amy, DG Joakim Larsson, Alejandro Amézquita, Peter Collignon, Kristian K. Brandt, David W. Graham, James M. 

Lazorchak et al. "Management options for reducing the release of antibiotics and antibiotic resistance genes to the 

environment." Environ Health Perspect 121, no. 8 (2013): 878-885. http://ehp.niehs.nih.gov/wpcontent/uploads/121/8/ehp.1206446.pdf. 5 http://www.fungi.com/about-paul-stamets.html, http://www.fungi.com/product-detail/product/mycelium-running.html. 6 Rigot, J.; Matsumura, F. Assessment of the rhizosphere competency and pentachlorophenol-metabolizing activity of a 

pesticide-degrading strain of Trichoderma harzianum introduced into the root zone of corn seedlings. Journal of 

Environmental Science and Health Part B Pesticides Food Contaminants and Agricultural Wastes. May, 2002. B37(3):201-

210.

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• A similar bioassay has been developed by Washington State University for aminopyralid.8

• North Carolina State University recommends a similar bioassay for all of the pyridine carboxylic 

acid herbicides –clopyralid, aminopyralid, and picloram.9

• Woods End Lab has also produced a bioassay for herbicide damage.10

A start

We don’t need to do all those things at once. Instead, we can start with one –say, dairy cow manure. (If 

that’s too limited, we can broaden the category.) The next step is to find experts who can help answer 

the above questions for dairy manure.

Meanwhile, we should also identify people who can help us identify the different categories of inputs we 

should work on over the course of the workplan. 

While this is presented as a report on progress and direction, comments from the public are welcome 

and encouraged.

See table below. 

Offfarm 

inputs

Source

Com

ponents 

of 

Interest

Possible/

likely 

Contamina

nts

Persists 

through 

Composti

ng?

Avoid

ance 

Methods

Enviro

nment

al Fate 

in Soil

Load

ing 

Rate

s 

Re

me

diat

ion

Test

ing 

Met

hod

s

Expert

s 

Yard 

waste

Munic

ipal 

collectio

n or 

compos

t

Lawn 

clippings

Gasoline/oil 

from 

mowers

No 

 Fertilizers

Not the 

fertilizer 

ingredient

s, but 

heavy 

metal 

contamina

nts would 

persist.

 

 

Insecticides 

--label 

search

Some?

Ordinanc

es 

restrictin

g use

 

7 http://puyallup.wsu.edu/soilmgmt/Pubs/CloBioassay.pdf. 8 http://whatcom.wsu.edu/ag/aminopyralid/bioassay.html. 9 http://www.ces.ncsu.edu/fletcher/programs/ncorganic/special-pubs/herbicide_carryover.pdf. 10 https://woodsend.org/compost/herbicide-bioassay/. 

Page 138 of 249
 

Herbicides -

-label 

search

Pyridine 

carboxylic 

acid 

herbicides.

Ordinanc

es 

restrictin

g use

 

Bioa

ssay

s. 

US 

Compo

sting 

Council

Dairy 

manur

e 

Conven

tional 

dairy

Feces

Antibiotics, 

other drugs 

--list

 

Use 

Organic 

source.

Other?

 

 Pesticides --

label search

Pyridine 

carboxylic 

acid 

herbicides

Use 

Organic 

source.

Other?

 

Bioa

ssay

s for 

herbi

cide

s.

 

 

Antibiotic 

resistance 

genes

 

 

Hay/ 

straw/ 

other 

bedding

Pesticides --

label search 

Use 

Organic 

source.

Other?

 

 Grain/ 

feed GMO grain 

Use 

Organic 

source.

Other?

 

 Pesticides --

label search 

Use 

Organic 

source.

Other?

 

 Feed 

additives 

Use 

Organic 

source.

Other?

 

Dairy 

manur

e 

CAFO Feces

Antibiotics, 

other drugs 

--list

 

Use 

Organic 

source.

Other?

 

 Pesticides --

label search

Pyridine 

carboxylic 

acid 

herbicides

Use 

Organic 

source.

Other?

 

Bioa

ssay

s for 

herbi

cide

s.

 

 

Antibiotic 

resistance 

genes

 

 

Hay/ 

straw/ 

other 

bedding

Pesticides --

label search 

Use 

Organic 

source.

Other?

 

Page 139 of 249
 Grain/ 

feed GMO grain 

Use 

Organic 

source.

Other?

 

 Pesticides --

label search 

Use 

Organic 

source.

Other?

 

 Feed 

additives 

Use 

Organic 

source.

Other?

 Dairy 

manure

Poultry 

manur

e 

Conven 

tional 

poultry 

opera 

tion

Feces

Antibiotics, 

other drugs 

--list

 

Use 

Organic 

source.

Other?

 

 Arsenic 

Use 

Organic 

source.

Testing.

 

 

Hay/ 

straw/ 

other 

bedding

Pesticides --

label search

Pyridine 

carboxylic 

acid 

herbicides

Use 

Organic 

source.

Other?

 

 Grain/ 

feed

Feed 

additives 

Use 

Organic 

source.

Other?

 

Hay for 

mulch

Conven 

tional

farm

Grass Pesticides --

label search

Pyridine 

carboxylic 

acid 

herbicides

Use 

Organic 

source.

Other?

 

Straw 

for 

mulch

Conven 

tional 

farm

Straw 

from 

grain

Pesticides --

label search 

Use 

Organic 

source.

Other?

 

Conve

ntional 

food 

scraps 

for 

compo

st

Various

: 

grocery 

stores, 

restau

rants, 

etc.

Vege

tables

Pesticides --

label search USCC

Grains Pesticides --

label search USCC

GMO grain

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Newsp

aper, 

other 

paper 

mulch 

materi

als

Newspa

pers, 

scrap 

paper

Inks, 

dyes

Heavy 

metals

Polycyclic 

aromatic 

hydro

carbons

Paper Dioxins

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