Sea foam is a type of foam created by the agitation of seawater, particularly when it contains higher concentrations of dissolved organic matter. Sea foam is a global phenomenon, and it varies depending on location and the potential influence of the surrounding marine, freshwater, and/or terrestrial environments. Sea foam is created when waves or strong winds inject air into the dissolved organic matter in ocean water, forming bubbles. The organic matter, mostly made of dead microscopic plants, contains a protein that gives the water enough surface tension to form bubbles. The composition of sea foam is generally a mixture of decomposed organic materials, including zooplankton, phytoplankton, algae (including diatoms), bacteria, fungi, protozoans, and vascular plant detritus, though each occurrence of sea foam varies in its specific contents. Sea foam is not harmful to humans in most cases and is often an indication of a productive ocean ecosystem. However, when large harmful algal blooms decay near shore, there is potential for impacts to human health and the environment. During blooms, popping sea foam bubbles are one way that algal toxins become airborne. The resulting aerosol can irritate the eyes of beachgoers and poses a health risk for those with asthma or other respiratory conditions.