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The idea of a tooth worm is a theory of the cause of dental caries, periodontitis and toothaches. Once widespread, the belief is now obsolete, having been superseded by more scientific rationales. It was supposed that the disease was caused by small worms resident within the tooth, eating it away. [1]
Usually, permitted point sources of water pollution, such as wastewater treatment plants, have high discharge treatment costs, whereas nonpoint sources of water pollution, such as agriculture, have low costs of pollution reduction. Therefore, it is generally assumed that most trades would take place between point sources and nonpoint sources. [54]
Sewage treatment plants mix these organisms as activated sludge or circulate water past organisms living on trickling filters or rotating biological contactors. [5] Aquatic vegetation may provide similar surface habitat for purifying bacteria, protozoa, and rotifers in a pond or marsh setting; although water circulation is often less effective.
The American Dental Association has reiterated its support for community water fluoridation to help prevent tooth decay. Studies show that community water fluoridation reduces tooth decay by more ...
This is in part because pollution causes so many diseases that it is often difficult to draw a straight line between cause and effect. There are many types of pollution-related diseases, including those caused by air pollution, contaminated soil, water pollution and lacking water, sanitation and hygiene (WASH). Air pollution can be reduced.
Typically, a parent may take a sick child to a traditional healer, who will look in the child's mouth and attribute the illness to "tooth worms".The healer will point out the small, white, developing tooth buds as being "tooth worms", and then dig the "worms" out of the gums without local anesthesia and using a non-sterile tool (normally a bicycle spoke). [2]
Limnodrilus hoffmeisteri is conveyor-belt feeder that ingests particles in deep sediments and egests them on the sediment surface in the form of pseudofeces. [5] [6] The activities of this worm can alter sediment stratification, [6] [7] [8] increase the water content and porosity of sediment, [9] change the distribution of sediment particle size, [6] [10] alter the oxygen and nutrient dynamics ...
These biological treatment systems effectively reduce water-borne diseases, dissolved organic carbon, turbidity and color in surface water, thus improving overall water quality. Typically in drinking water treatment; granular activated carbon or sand filters are used to prevent re-growth of microorganisms in water distribution pipes by reducing ...