What symptoms may healthy adults experience when exposed to low concentrations of carbon monoxide?

Healthy adults exposed to low concentrations of carbon monoxide (CO) may experience headaches and nausea as a result of the gas interfering with the body’s ability to transport oxygen. Carbon monoxide binds to hemoglobin in the blood more effectively than oxygen, which can lead to decreased oxygen delivery to various tissues. This effect is often felt as a headache, which can occur due to the brain's sensitivity to reduced oxygen levels. Nausea is another common symptom that can arise as the body responds to the presence of CO and its effects on overall health.

While other symptoms mentioned, such as dizziness and fatigue, are certainly possible with CO exposure, the combination of headaches and nausea is particularly associated with the body's reaction to low levels of this harmful gas, making these two symptoms more distinctive in such exposure scenarios.