Certified in Public Health (CPH) Practice Exam

Why is Cryptosporidium a concern in municipal water supplies?

1. Bioaccumulates in fish

2. Can survive the chlorine treatment process

3. Can infect the lungs when water is vaporized, such as in a shower

4. Can bore directly through the skin

The correct answer is: Can survive the chlorine treatment process

The concern regarding Cryptosporidium in municipal water supplies primarily stems from its ability to survive the chlorine treatment process. Chlorine is commonly used to disinfect drinking water and eliminate pathogens. However, Cryptosporidium is particularly resilient and can persist in chlorinated water systems, which poses a significant risk of waterborne outbreaks. Unlike many other waterborne pathogens, Cryptosporidium's oocysts are resistant to chlorine and can remain viable even when subjected to standard disinfection protocols. This characteristic makes it challenging for municipal systems to ensure safe drinking water, especially during high-turbidity events such as heavy rainfall or flooding, which can lead to cryptosporidial contamination from runoff. Therefore, increased awareness and specific monitoring for Cryptosporidium in the water supply are essential for public health, as it can lead to gastrointestinal illness if ingested. While the other choices address different aspects of Cryptosporidium's threat or biological characteristics, they do not directly relate to its relevance in municipal water supplies. For instance, its potential to affect fish indicates ecological impacts rather than direct human health risks via water. The ability to infect the lungs suggests a pathway of transmission that is not the primary concern when discussing public water supplies. The notion of boring through the