How does chronic exposure to N2O affect vitamin B12 metabolism?

Chronic exposure to nitrous oxide (N2O) can indeed lead to deficiencies in vitamin B12 metabolism and related health issues. This occurs because N2O inactivates vitamin B12 by oxidizing the cobalt atom present in its structure, specifically affecting the enzyme methionine synthase which relies on vitamin B12 as a cofactor. When this process is impaired, there is a decrease in the synthesis of methionine from homocysteine, leading to elevated homocysteine levels, which is associated with several health complications, including neurological disorders and anemia.

Long-term exposure to nitrous oxide can therefore undermine the body's ability to utilize vitamin B12 effectively, leading to deficiencies and subsequent health problems. This relationship emphasizes the importance of monitoring vitamin B12 levels in individuals who are frequently exposed to nitrous oxide, particularly in clinical or occupational settings where its use is common.