CHROMagar™ CCA (Powder Pack, 500G)

For the Detection and Enumeration of E. coli and Coliform Bacteria in Water According to ISO 9308-1

CHROMagar™ CCA is a selective chromogenic culture medium designed for the simultaneous detection, enumeration, and differentiation of Escherichia coli and other coliform bacteria in water samples, in full compliance with ISO 9308-1 standards. This medium is particularly suitable for drinking water, swimming pool water, and treated water samples, where bacterial counts are low and require precise enumeration.

Colony Appearance

Performance

Coliform bacteria, particularly E. coli, are widely used as indicators of water quality. Their presence suggests organic or fecal contamination, which may be associated with pathogens such as Salmonella, Vibrio, or enteric viruses. Regulatory agencies worldwide require routine testing for E. coli and coliforms to ensure drinking water safety and proper functioning of water treatment systems.

CHROMagar™ CCA simplifies and improves the detection process by:

• Combining E. coli and coliform detection into a single medium
• Allowing easy colony distinction based on color
• Supporting direct enumeration for low-burden water samples

Intended Use

CHROMagar™ CCA is intended for the qualitative and quantitative detection of E. coli and other coliforms in:

• Drinking water
• Bottled water
• Pool and recreational waters
• Finished or treated water (post-treatment)
• Groundwater and environmental samples

This medium is especially useful in routine water quality monitoring, sanitary surveillance, and compliance testing with ISO 9308-1.

Advantages

1. Simultaneous Detection in One Medium
   E. coli and coliforms are detected and visually differentiated on the same plate, eliminating the need for multiple culture steps.
2. Clear, Color-Based Differentiation
   E. coli colonies develop a metallic blue to violet hue, while other coliforms appear pink to red, enabling quick and accurate colony counting.
3. Ideal for Low-Colony-Count Samples
   Designed for samples expected to yield fewer than 100 colonies, making it perfect for drinking water and post-treatment water testing.
4. Reduced Workload
   Compared to traditional MI agar or MPN methods, CHROMagar™ CCA saves time, reduces complexity, and minimizes false positives.

Test Procedure

1. Sample Preparation: Follow ISO 9308-1 guidelines for membrane filtration or direct plating.
2. Inoculation: Place filtered membrane or direct sample onto prepared CHROMagar™ CCA plate.
3. Incubation:
   • Temperature: 36 ± 2 °C
   • Time: 18–24 hours
   • Atmosphere: Aerobic
4. Interpretation:
   • Count and differentiate E. coli and coliform colonies by color
   • Report results in CFU per 100 mL

Ordering Information

Storage & Shelf Life

• Storage Conditions: 2–8 °C, dry and sealed
• Shelf Life: Up to 24 months from date of manufacture
• Prepared Media: Use within validated shelf-life per instructions

CHROMagar™ CCA is a powerful, ISO-compliant solution for water microbiology laboratories seeking accurate, efficient, and cost-effective enumeration of E. coli and coliforms. With its simple color-based interpretation, reduced false positives, and suitability for low-burden samples, it is the ideal medium for routine water quality testing and regulatory compliance.