January 13, 2026 — The next time you take a breath, it is worth remembering that much of that oxygen can be traced back to microscopic ocean algae. Their ability to produce oxygen through photosynthesis is supported by iron dust that settles into the sea.
A new study from Rutgers University, published in the Proceedings of the National Academy of Sciences, offers a clearer picture of how this essential process works and why it matters for life on Earth.
Iron and the Ocean’s Oxygen Producers
Marine phytoplankton are tiny algae that sit at the base of ocean food webs. These organisms rely on iron, a vital micronutrient, to grow and function. Iron reaches the oceans mainly through airborne dust from deserts and dry regions, as well as through meltwater released by glaciers.
“Every other breath you take includes oxygen from the ocean, released from phytoplankton,” said Paul G. Falkowski, the Bennett L. Smith Chair in Business and Natural Resources at Rutgers-New Brunswick and a co-author of the study. “Our research shows that iron is a limiting factor in phytoplankton’s ability to make oxygen in vast regions of the ocean.”
Without enough iron, photosynthesis slows down or stops altogether. Photosynthesis is the process of converting light energy into chemical energy while releasing oxygen. When this process falters, phytoplankton grow more slowly, capture less sunlight, and remove less carbon dioxide from the atmosphere.