Which of the following is indicative of "blue baby syndrome"?

"Blue baby syndrome," also known as methemoglobinemia, is a condition that primarily affects infants and is characterized by a deficiency in the ability of hemoglobin to carry oxygen in the blood. This reduction in the oxygen-carrying capacity leads to a blue or bluish discoloration of the skin, particularly noticeable in the facial area, which is where the term "blue baby" originates. Additionally, as the body struggles to transport adequate oxygen, affected individuals may also experience shortness of breath.

The association of blueness of the skin and shortness of breath with this syndrome highlights the physiological impacts of reduced oxygen saturation, demonstrating how critical enough oxygen is for maintaining a healthy appearance and function. Understanding this condition is essential for water operators, particularly since contamination with nitrates can lead to such health implications. Thus, recognizing the symptoms enables timely intervention and prevention strategies in communities where water quality may be compromised.