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Brand kept his discovery secret, as alchemists of the time did, and worked with the phosphorus trying unsuccessfully to use it to produce gold. His recipe was: [5] Let urine stand for days until it gives off a pungent smell. [4] (This step was not necessary, as later scientists discovered that fresh urine yielded the same amount of phosphorus). [6]
Phosphorus: 1669 H. Brand: 1669 H. Brand Prepared and isolated from urine, it was the first element whose discovery date and discoverer are recorded. [53] Its name first appears in print in the work of Georg Kaspar Kirchmayer in 1676. Recognised as an element by Lavoisier. [3] 1 Hydrogen: 1671 R. Boyle: 1671 R. Boyle
Phosphorus is a finite (limited) resource that is widespread in the Earth's crust and in living organisms but is relatively scarce in concentrated forms, which are not evenly distributed across the Earth. The only cost-effective production method to date is the mining of phosphate rock, but only a few countries have significant commercial reserves.
Toxicology testing, also known as safety assessment, or toxicity testing, is the process of determining the degree to which a substance of interest negatively impacts the normal biological functions of an organism, given a certain exposure duration, route of exposure, and substance concentration.
In 2010 Powles stated: "glyphosate is a one in a 100-year discovery that is as important for reliable global food production as penicillin is for battling disease." [ 32 ] As of April 2017, the Canadian government stated that glyphosate was "the most widely used herbicide in Canada", [ 33 ] at which date the product labels were revised to ...
The Alchemist Discovering Phosphorus is a painting by Joseph Wright of Derby originally completed in 1771 then reworked in 1795. [1] The full title of the painting is The Alchymist, in Search of the Philosopher's Stone, Discovers Phosphorus, and prays for the successful Conclusion of his operation, as was the custom of the Ancient Chymical Astrologers.
In vitro toxicity testing is the scientific analysis of the toxic effects of chemical substances on cultured bacteria or mammalian cells. [1] In vitro (literally 'in glass') testing methods are employed primarily to identify potentially hazardous chemicals and/or to confirm the lack of certain toxic properties in the early stages of the development of potentially useful new substances such as ...
A toxicologist working in a lab (United States, 2008)Toxicology is a scientific discipline, overlapping with biology, chemistry, pharmacology, and medicine, that involves the study of the adverse effects of chemical substances on living organisms [1] and the practice of diagnosing and treating exposures to toxins and toxicants.