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  2. Contaminant Candidate List (CCL) and Regulatory Determination

Draft CCL 6 Microbial Contaminants

Microbial NameType of Microorganism
Acanthamoeba spp.Protozoa
Balamuthia mandrillarisProtozoa
CalicivirusVirus
Campylobacter jejuniBacteria
Escherichia coli (O157)Bacteria
Legionella pneumophilaBacteria
Pathogenic waterborne mycobacteria group (includes M. avium, M. abscessus, M. fortuitum, M. gordonae, M. mucogenicum, M. chelonae, M. kansasii, M. xenopi, and M. intracellulare)  Bacteria
Naegleria fowleriProtozoa
Pseudomonas aeruginosaBacteria

Contaminant Candidate List (CCL) and Regulatory Determination

  • Basic Information
  • Contaminant Candidate List 6
  • Contaminant Candidate List 5
  • Contaminant Candidate List 4
  • Contaminant Candidate List 3
  • Contaminant Candidate List 2
  • Contaminant Candidate List 1
  • Regulatory Determination 5
  • Regulatory Determination 4
  • Regulatory Determination 3
  • Regulatory Determination 2
  • Regulatory Determination 1
  • Types of Drinking Water Contaminants
Contact Us About the CCL and Regulatory Determinations
Contact Us About the CCL and Regulatory Determinations to ask a question, provide feedback, or report a problem.
Last updated on April 2, 2026
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