Re: How is Urea collected and used?

It depends entirely on the supplier. While it is true that urea can be isolated from the urines of most land mammals, it can also be synthesized quite inexpensively from inorganic materials. In fact, the synthesis of urea was the first disproof of the theory that organic compounds were distinct from inorganic compounds (see this previous answer by Dan Berger for more: Re: what is the difference detween an inorganic and organic compound?). Urea can be made from the reaction of ammonia with carbon dioxide, carbon monoxide, or even cyanate under the right conditions. As such, much of the available urea in use today originates from refineries like Standard Tar Products. While it is certainly possible to isolate and purify urea from bovine urine, and there are certainly a large number of urinating bovines in the United States, this is only one possible source and may not be the most economically feasible for most standards of purity.