Abstract

A portion of the charcoal and soot produced due to wildfires and combustion of fossil fuels on land enters the atmosphere and aquatic systems as black carbon (BC). Much of the airborne BC has a diameter of a few nanometers to tens of micrometers. This particulate matter (PM), especially around or smaller than 1um (PM1), can travel for thousands of kilometers and deposits in the oceans. Most of the riverine PM also discharges into the oceans eventually. It is known that the PM settles into the sediments, but it has only recently been reported that PM1 enters the sea anemone around the coastal waters of Taiwan. It is natural to suspect that sea anemones elsewhere and other marine animals would also absorb or otherwise retain PM in their bodies. Here we show that indeed PM is detected in corals. PM is often associated with potentially toxic trace metals and organic compounds; how PM would affect the physiology of marine animals and eventually influence human health deserves attention.