When.com Web Search

  1. Ad

    related to: first record of spermicides in water treatment is called a small part

Search results

  1. Results From The WOW.Com Content Network
  2. History of water supply and sanitation - Wikipedia

    en.wikipedia.org/wiki/History_of_water_supply...

    The Metropolis Water Act introduced the regulation of the water supply companies in London, including minimum standards of water quality for the first time. The Act "made provision for securing the supply to the Metropolis of pure and wholesome water", and required that all water be "effectually filtered" from 31 December 1855. [ 125 ]

  3. Spermicide - Wikipedia

    en.wikipedia.org/wiki/Spermicide

    The most common active ingredient of spermicides is nonoxynol-9. Spermicides containing nonoxynol-9 are available in many forms, such as jelly (gel), films, and foams. Used alone, spermicides have a perfect use failure rate of 6% per year when used correctly and consistently, and 16% failure rate per year in typical use. [1]

  4. History of municipal treatment of drinking water - Wikipedia

    en.wikipedia.org/wiki/History_of_municipal...

    Water closets could now empty into the cities sewer which in turn emptied into the Thames. [8] This was a disaster for the river. In 1816 salmon could be caught in the Thames, four years later none could be caught. The water closet overloaded the medieval cesspool system which was still in use. The use of water to dispose of sewage in the water ...

  5. Water treatment - Wikipedia

    en.wikipedia.org/wiki/Water_treatment

    Dalecarlia Water Treatment Plant, Washington, D.C. Water treatment is any process that improves the quality of water to make it appropriate for a specific end-use. The end use may be drinking, industrial water supply, irrigation, river flow maintenance, water recreation or many other uses, including being safely returned to the environment.

  6. Environmental Health

    images.huffingtonpost.com/2009-01-27-1476069x82.pdf

    Background Chlorine and caustic soda are produced at chlor-alkali plants using mercury cells or the increasingly popular membrane technology that is mercury free and more energy-

  7. Reversible inhibition of sperm under guidance - Wikipedia

    en.wikipedia.org/wiki/Reversible_inhibition_of...

    Diagram showing the site of injection of the product Vasalgel, a vasectomy alternative. Reversible inhibition of sperm under guidance (RISUG), formerly referred to as the synthetic polymer styrene maleic anhydride (SMA), is the development name of a male contraceptive injection developed at IIT Kharagpur in India by the team of Dr. Sujoy K. Guha.

  8. Biofilter - Wikipedia

    en.wikipedia.org/wiki/Biofilter

    Biofiltration was first introduced in England in 1893 as a trickling filter for wastewater treatment and has since been successfully used for the treatment of different types of water. [5] Biological treatment has been used in Europe to filter surface water for drinking purposes since the early 1900s and is now receiving more interest worldwide.

  9. Explainer-What is fluoride and why is it added to the US ...

    www.aol.com/news/explainer-fluoride-why-added-us...

    The U.S. Centers for Disease Control and Prevention has called fluoridation of drinking water one of the nation's top 10 public health achievements of the 20th century, noting that it effectively ...