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  2. Contaminant Candidate List (CCL) and Regulatory Determination

CCL 5 Microbial Contaminants

Microbial Name Type of Microorganism Diseases and Infections
Adenovirus Virus Respiratory illness and occasionally gastrointestinal illness.
Caliciviruses Virus (includes Norovirus) Mild self-limiting gastrointestinal illness.
Campylobacter jejuni Bacterium Mild self-limiting gastrointestinal illness.
Enteroviruses Viruses including polioviruses, coxsackieviruses, and echoviruses Mild respiratory illness.
Escherichia coli (O157) Bacterium Gastrointestinal illness and kidney failure.
Helicobacter pylori Bacterium Capable of colonizing the human gut and can cause  ulcers and cancer.
Legionella pneumophila Bacterium Lung diseases when inhaled.
Mycobacterium abscessus Bacterium Lung infection in those with underlying lung disease, such as cystic fibrosis. May cause skin and soft tissue infections.
Mycobacterium avium Bacterium Lung infection in those with underlying lung disease and disseminated infection in the severely immunocompromised.

Naegleria fowleri

Protozoan Primary amebic meningoencephalitis (PAM)
Pseudomonas aeruginosa Bacterium Pneumonia, infections in the blood, or other parts of the body after surgery.
Shigella sonnei Bacterium Mild self-limiting gastrointestinal illness and bloody diarrhea.

Contaminant Candidate List (CCL) and Regulatory Determination

  • Basic Information
  • Draft 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 to ask a question, provide feedback, or report a problem.
Last updated on October 22, 2024
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