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4-120 – Contaminant Testing

Basis and Purpose

The statutory authority for this rule includes but is not limited to sections 44-10-202(1)(c), 44-10-203(1)(a), 44-10-203(1)(c), 44-10-203(1)(g), 44-10-203(1)(j), 44-10-203(2)(d), 44-10-203(2)(f), 44-10-203(3)(d), 44- 10-203(3)(e), 44-10-501(6), 44-10-502(3), 44-10-503(8), 44-10-504(1)(b), 44-10-504(2), 44-10-601(4), 44-10-602(4), 44-10-603(6), 44-10-604(1)(b), and 44-10-604(2), C.R.S. Authority also exists in the Colorado Constitution at Article XVIII, Subsection 16(5)(a)(VII). The purpose of this rule is to protect the public health and safety by establishing the contaminant testing and related process validation portion of the Division’s Regulated Marijuana sampling and testing program. This Rule 4-120 was previously Rules M and R 1501, 1 CCR 212-1 and 1 CCR 212-2.

A. Contaminant Testing Required

  1. Unless a Medical Marijuana Cultivation Facility’s or a Medical Marijuana Products Manufacturer’s cultivation or production process has achieved process validation under this Rule, it shall not Transfer or process into a Medical Marijuana Concentrate or Medical Marijuana Product any Medical Marijuana unless Samples from each Harvest Batch or Production Batch from which that Medical Marijuana was derived has been tested by a Medical Marijuana Testing Facility for contaminants and passed all contaminant tests required by this Rule, except as permitted in Rule 5-205(C).
  2. Unless a Retail Marijuana Cultivation Facility’s or a Retail Marijuana Product Manufacturing Facility’s cultivation or production process has achieved process validation under this Rule, it shall not Transfer, or process into a Retail Marijuana Concentrate or Retail Marijuana Product any Retail Marijuana unless Samples from each Harvest Batch or Production Batch from which that Retail Marijuana was derived has been tested by a Retail Marijuana Testing Facility for contaminants and passed all contaminant tests required by this Rule, except as permitted in Rule 6-205(C).

B. Process Validation and Ongoing Testing – Contaminant Testing

  1. Regulated Marijuana. A Medical Marijuana Cultivation Facility’s or a Retail Marijuana Cultivation Facility’s cultivation process shall be deemed validated for Contaminant testing if every Harvest Batch that it produced during at least a six-week period but no longer than a 12-week period passed all contaminant tests required by Paragraph (C) of this Rule. This must include at least six Test Batches. A Medical Marijuana Cultivation Facility or a Retail Marijuana Cultivation Facility can obtain process validation for all contaminants listed in paragraph (C) of this Rule at the same time or separately for each contaminant.
    • Visual Microbial Growth. If a Medical Marijuana Cultivation Facility or Retail Marijuana Cultivation Facility is aware that a Harvest Batch contains visual microbial contamination, the Medical Marijuana Cultivation Facility or Retail Marijuana Cultivation Facility shall subject the Harvest Batch to microbial contaminant testing pursuant to Rule 4-120(C)(1). If the Test Batch fails testing, then the Harvest Batch shall be subject to the requirements in Rule 4-135(C). The Licensees must also follow Rule 4-120(F)(2).
  2. Regulated Marijuana Concentrate or Regulated Marijuana Product. A Medical Marijuana Cultivation Facility’s, Retail Marijuana Cultivation Facility’s, Medical Marijuana Products Manufacturer’s, or a Retail Marijuana Products Manufacturer’s production process shall be deemed validated for contaminant testing if every Production Batch that it produced during at least a four-week period but no longer than an eight-week period passed all contaminant tests required by Paragraph (C) of this Rule. This must include Test Batches from at least four Production Batches.
  3. Process Validation is Effective for One Year. Once a Medical Marijuana Cultivation Facility, Retail Marijuana Cultivation Facility, Medical Marijuana Products Manufacturer, or Retail Marijuana Products Manufacturer has successfully obtained process validation for each of the contaminants listed in paragraph (C) of this Rule, the process validation shall be effective for one year from the date of the last passing test required to satisfy the process validation requirements.
  4. Regulated Marijuana Ongoing Contaminant Testing. After successfully obtaining process validation, once every 30 days a Medical Marijuana Cultivation Facility or a Retail Marijuana Cultivation Facility shall subject at least one Harvest Batch to all contaminant testing required by Paragraph (C) of this Rule. If during any 30-day period a Medical Marijuana Cultivation Facility or a Retail Marijuana Cultivation Facility does not possess a Harvest Batch that is ready for testing, the Medical Marijuana Cultivation Facility or Retail Marijuana Cultivation Facility must subject its first Harvest Batch that is ready for testing to the required contaminant testing prior to Transfer or processing of the Regulated Marijuana. If a Harvest Batch subject to ongoing contaminant testing fails contaminant testing, the Medical Marijuana Cultivation Facility or Retail Marijuana Cultivation Facility shall follow the procedure in Paragraph (F)(2) of this Rule. Ongoing contaminant testing pursuant to this Rule 4-120 shall be subject to the requirements in Rule 4-110. See Rule 4-110(A) – Collection of Samples.
    • The Division may reduce the frequency of ongoing contaminant testing required by Medical Marijuana Cultivation Facilities and Retail Marijuana Cultivation Facilities if the Division has reasonable grounds to believe Medical Marijuana Testing Facilities and Retail Marijuana Testing Facilities have reached maximum capacity to perform testing required by this Rule. The Division will provide notification of any reduction to the frequency of ongoing contaminant testing to the Licensee’s last electronic mailing address provided to the Division.
  5. If the Licensee fails to comply with paragraph (B)(4) of this Rule, the Medical Marijuana Cultivation Facility or Retail Marijuana Cultivation Facility is no longer process validated.5. Regulated Marijuana Concentrate or Regulated Marijuana Product Ongoing Contaminant Testing. After successfully obtaining process validation, once every 30 days a Medical Marijuana Cultivation Facility, Retail Marijuana Cultivation Facility, Medical Marijuana Products Manufacturer, or Retail Marijuana Products Manufacturer shall subject at least one Production Batch to all contaminant testing required by Paragraph (C) of this Rule. If during any 30-day period a Medical Marijuana Cultivation Facility, Retail Marijuana Cultivation Facility, Medical Marijuana Products Manufacturer, or Retail Marijuana Products Manufacturer does not possess a Production Batch that is ready for testing, the Medical Marijuana Cultivation Facility, Retail Marijuana Cultivation Facility, Medical Marijuana Products Manufacturer, or Retail Marijuana Products Manufacturer must subject its first Production Batch that is ready for testing to the required contaminant testing prior to Transfer or processing of the Regulated Marijuana. If a Production Batch submitted for ongoing contaminant testing fails contaminant testing, the Medical Marijuana Cultivation Facility, Retail Marijuana Cultivation Facility, Medical Marijuana Products Manufacturer, or Retail Marijuana Products Manufacturer shall follow the procedure in Paragraph (F)(2) of this Rule.
    • The Division may reduce the frequency of ongoing contaminant testing required by Medical Marijuana Cultivation Facilities, Retail Marijuana Cultivation Facilities, Medical Marijuana Products Manufacturers, and Retail Marijuana Products Manufacturers if the Division has reasonable grounds to believe Medical Marijuana Testing Facilities and Retail Marijuana Testing Facilities have reached maximum capacity to perform testing required by this Rule. The Division will provide notification of any reduction to the frequency of ongoing contaminant testing to the Licensee’s last electronic mailing address provided to the Division.
    • If the Licensee fails to comply with paragraph (B)(5) of this Rule, the Medical Marijuana Cultivation Facility or Retail Marijuana Cultivation Facility is no longer process validated

C. Required Contaminant Tests.

  1. Microbial Contaminant Testing. Harvest Batches of Regulated Marijuana, Production Batches of Water, Heat/Pressure-, or Food-Based Medical Marijuana Concentrate, Production Batches of Water, Heat/Pressure-, or Food-Based Retail Marijuana Concentrate, Regulated Marijuana Product, and Audited Product must be tested for microbial contamination by a Medical Marijuana Testing Facility or a Retail Marijuana Testing Facility at the frequency established by Paragraphs (A) and (B) of this Rule. The microbial contamination test must include, but need not be limited to, testing to determine the presence of and amounts present of microbial contaminants listed in Rule 4- 115(E)(1).
  2. Residual Solvent Contaminant Testing. Production Batches of Solvent-Based Medical Marijuana Concentrate, Solvent-Based Retail Marijuana Concentrate, and Audited Product that contains any Solvent-Based Medical Marijuana Concentrate or SolventBased Retail Marijuana Concentrate produced by a Medical Marijuana Products Manufacturer or Retail Marijuana Products Manufacturer must be tested by a Medical Marijuana Testing Facility or a Retail Marijuana Testing Facility for residual solvent contamination at the frequency established by Paragraphs (A) and (B) of this Rule. The residual solvent contamination test must include, but need not be limited to, testing to determine the presence of, and amounts present of acetone, butane, ethanol, heptanes, isopropyl alcohol, propane, benzene*, toluene*, pentane, hexane*, methanol, ethyl acetate, and total xylenes* (m, p, o – xylenes).

    * Note: These solvents are not approved for use. Testing is required for these solvents due to their possible presence in the solvents approved for use per Rule 5-315 and 6- 315.
  3. Mycotoxin Contaminant Testing. As part of Remediation, each Production Batch of Solvent-Based Medical Marijuana Concentrate produced by a Medical Marijuana Products Manufacturer or Solvent-Based Retail Marijuana Concentrate produced by a Retail Marijuana Products Manufacturer from Regulated Marijuana that failed microbial contaminant testing produced must be tested by a Medical Marijuana Testing Facility or a Retail Marijuana Testing Facility for mycotoxin contamination. The mycotoxin contaminant test must include, but need not be limited to, testing to determine the presence of, and amounts present of, aflatoxins (B1, B2, G1, and G2) and ochratoxin A. This is in addition to all other contaminant testing required by this Paragraph (C). This contaminant test cannot be process validated in accordance with subparagraph (B)(2) of this Rule.
  4. Pesticide Contaminant Testing. Harvest Batches of Regulated Marijuana must be tested for Pesticide contamination by a Medical Marijuana Testing Facility or a Retail Marijuana Testing Facility at the frequency established by this Rule 4-120(A) and (B). The Pesticide contamination test must include, but need not be limited to, testing to determine the presence of, and amounts present of, the Pesticides listed in Rule 4-115(E)(5).
  5. Metals Contaminant Testing. Each Harvest Batch and Production Batch of Regulated Marijuana must be tested for metals contamination by a Medical Marijuana Testing Facility or a Retail Marijuana Testing Facility at the frequency established in paragraphs (A) and (B) of this Rule. The metals contamination test must include, but need not be limited to, testing to determine the presence of, and amounts present of, arsenic, cadmium, lead, and mercury.

D. Additional Required Tests

The Division may require additional tests to be conducted on a Harvest Batch or Production Batch prior to a Medical Marijuana Cultivation Facility, Retail Marijuana Cultivation Facility, Medical Marijuana Products Manufacturer, or a Retail Marijuana Products Manufacturer Transferring, or processing into a Medical Marijuana Concentrate, Retail Marijuana Concentrate, Medical Marijuana Product, or Retail Marijuana Product any Regulated Marijuana from that Harvest Batch or Production Batch. Additional tests may include, but need not be limited to, screening for Pesticide, chemical contaminants, biological contaminants, or other types of microbials, molds, metals, or residual solvents.

E. Exemptions

  1. Medical Marijuana Concentrate
    • A Medical Marijuana Products Manufacturer who combines multiple Production Batches of Solvent-Based Medical Marijuana Concentrate into a Production Batch of Solvent-Based Medical Marijuana Concentrate shall be considered exempt from residual solvent testing pursuant to this Rule and the 4-100 Series Rules only if all original Production Batches passed residual solvent testing. This does not apply if a solvent, Additive, or any other Ingredient was introduced during the combination of the Production Batches.
    • A Production Batch of Medical Marijuana Concentrate shall be considered exempt from this Rule if the Medical Marijuana Products Manufacturer that produced it does not Transfer any portion of the Production Batch and uses the entire Production Batch to manufacture Medical Marijuana Product, except that a Solvent-Based Medical Marijuana Concentrate must still be submitted for residual solvent contaminant testing. The manufactured Medical Marijuana Product shall be subject to mandatory testing under this Rule.
  2. Retail Marijuana Concentrate
    • A Retail Marijuana Products Manufacturer who combines multiple Production Batches of Solvent-Based Retail Marijuana Concentrate into a Production Batch of Solvent-Based Retail Marijuana Concentrate shall be considered exempt from residual solvent testing pursuant to this Rule and the 4-100 Series Rules only if all original Production Batches passed residual solvent testing. This does not apply if a solvent, Additive or any other Ingredient was introduced during the combination of the Production Batches.
    • A Production Batch of Retail Marijuana Concentrate shall be considered exempt from this Rule if the Retail Marijuana Products Manufacturer that produced it does not Transfer any portion of the Production Batch and uses the entire Production Batch to manufacture Retail Marijuana Product, except that a Solvent-Based Retail Marijuana Concentrate must still be submitted for residual solvent contaminant testing. The manufactured Retail Marijuana Product shall be subject to testing under this Rule.

F. Required Re-Validation – Contaminants

  1. Material Change Re-Validation. If a Medical Marijuana Cultivation Facility, Retail Marijuana Cultivation Facility, Medical Marijuana Products Manufacturer, or a Retail Marijuana Products Manufacturer makes a Material Change to its cultivation or production process or its standard operating procedure manual, then it must have the first five Harvest Batches or Production Batches produced using the new procedures tested for all of the contaminants required by Paragraph (C) of this Rule regardless of whether its process has been previously validated regarding contaminants. If any of those tests fail, then the Regulated Marijuana Business’s process must be re-validated.
    • Pesticide. It is a Material Change if a Medical Marijuana Cultivation Facility or Retail Marijuana Cultivation Facility begins using a new or different Pesticide during its cultivation process.
    • Solvents. It is a Material Change if a Medical Marijuana Products Manufacturer or Retail Marijuana Products Manufacturer begins using a new or different solvent or combination of solvents or changes any parameters for equipment related to the solvent purging process, including but not limited to, time, temperature, or pressure.
    • Cultivation. It is a Material Change if a Medical Marijuana Cultivation Facility or a Retail Marijuana Cultivation Facility begins using a new or different method for any material part of the cultivation process, including, but not limited to, changing from one growing medium to another.
    • Notification. A Medical Marijuana Cultivation Facility, Retail Marijuana Cultivation Facility, Medical Marijuana Products Manufacturer, or a Retail Marijuana Products Manufacturer must notify the Medical Marijuana Testing Facility or the Retail Marijuana Testing Facility of the Material Change. e. Testing Required Prior to Transfer or Processing. When a Harvest Batch or Production Batch is required to be submitted for testing pursuant to this Rule, the Medical Marijuana Cultivation Facility, Retail Marijuana Cultivation Facility, Medical Marijuana Products Manufacturer, or Retail Marijuana Products Manufacturer that produced it may not Transfer or process into a Medical Marijuana Concentrate, Retail Marijuana Concentrate, Medical Marijuana Product, or Retail Marijuana Product any of the Regulated Marijuana from that Harvest Batch or Production Batch unless and until the Harvest Batch or Production Batch passes all required testing.
  2. Failed Contaminant Testing and Re-Validation. Failed contaminant testing may constitute a violation of these rules.
    • If a Sample is required to be tested by these Rules or required to be tested by the Division pursuant to Rule 4-120(A) and fails contaminant testing, the Medical Marijuana Cultivation Facility, Retail Marijuana Cultivation Facility, Medical Marijuana Products Manufacturer, or Retail Marijuana Products Manufacturer shall follow the procedures in Rule 4-135(B) for any Inventory Tracking System package, Harvest Batch, or Production Batch from which the failed Sample was taken.
    • The Medical Marijuana Cultivation Facility, Retail Marijuana Cultivation Facility, Medical Marijuana Products Manufacturer, or Retail Marijuana Products Manufacturer shall also submit Test Batches from three new Harvest Batches or Production Batches of the Regulated Marijuana for contaminant testing by a Medical Marijuana Testing Facility or a Retail Marijuana Testing Facility within no more than 30 days. If any one of the three submitted Test Batches fails contaminant testing, the Medical Marijuana Cultivation Facility, Retail Marijuana Cultivation Facility, Medical Marijuana Products Manufacturer, or Retail Marijuana Products Manufacturer shall re-validate its process for contaminants

G. Violation Affecting Public Safety

Failure to comply with this Rule may constitute a license violation affecting public safety.


*LEGAL DISCLAIMER* 

The above links are provided as a courtesy to assist Medical and Retail Marijuana Business Licensees in complying with the Marijuana Rules, 1 CCR 212-3. These links are provided only as a courtesy, and therefore neither these documents nor the information contained therein shall be represented, relied upon, or referenced, in any manner, as an official legal source.  Official Rules are available on the 
Colorado Secretary of State’s Code of Regulations available on their Administrative Rules of State Agencies webpage.

Updated on May 26, 2020

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