Foam and Foam Formation
release of dissolved organic matter from the decay of plant and animal material
is the primary source of naturally occurring foams. Persistent
foam bubbles are a result of these compounds reducing the surface tension of
water in the same way the soap does. These natural surfactants are made up of carboxylic
fatty acids derived from plant lipids, lignins from wood, bits of protein and
dissolved organic matter. Generally naturally occurring foams are non-toxic, short-lived and become
a brownish colour as they age.
Foams can also be produced by man-made compounds. Compounds such as detergents, shampoos and weedkillers can cause the formation of foam. Foams that are due to man-made compounds tend to
remain white in colour, break down rapidly and are likely to appear close to the original source. Synthetic foams have the potential to be harmful to the aquatic environment.
In rivers and streams the flow of water results in the formation of foam. In lakes and dams, it is the wind that agitates the water surface and results in the formation of foam. In estuaries wind also results in the formation of foams as do the currents associated with tidal movement.
action in the marine environment contributes to the formation of foam through the agitation of seawater.
Sea foam or spume as it is commonly termed occurs worldwide and varies in
extent due to location, surrounding marine, freshwater and or terrestrial
inputs and prevailing climatic conditions.
and rivers the foam bubbles tend to accumulate and form foam lines where areas of different flow
meet, such as at confluences of streams, in eddies or below waterfalls. In
lakes, foams lines tend to be a result of prevailing winds rather than water currents and commonly form 'windrows' which accumulate on the windward shoreline.
In estuaries and marine environments flow lines tend to be a result of converging
tidal currents, river outflows, wind action or a combination thereof. Wave action also contributes to
the formation of foam through the agitation of seawater. The extent of a foam line is dependent on the prevailing weather conditions
Issues relating to foams
Should you have concerns relating to foams in your area, and,
Contact the EPA Incident Response Hotline 1800 005 171, or email to email@example.com
Or if non-urgent
Email to firstname.lastname@example.org