Bodily process for disposing of undigested food waste products and nitrogenous by-products of metabolism, regulating water content, maintaining acid-base balance, and controlling osmotic pressure to promote homeostasis. It refers to both urination and defecation and to the processes that take place in the digestive and urinary systems, as the kidney and liver filter wastes, toxins, and drugs from the blood and food reaches the last stage of digestion. Ammonia from protein digestion, the primary excretory product, is converted to urea to be excreted in urine.
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The other boroughs — that is to say the City of Westminster and the City of London along with Bexley, Bromley, Croydon, Greenwich, Kingston, Lewisham, Merton, Southwark, Sutton and Tower Hamlets — are independent waste authorities in their own right.
The ODPM have recently proposed, as part of other transfers of powers to the Greater London Authority, to give it a waste function. The Mayor of London has made repeated attempts to bring the different waste authorities together, to form a single waste authority in London. This has faced significant opposition from existing authorities. However, it has had significant support from all other sectors and the surrounding regions managing most of London's waste.