Editing Contamination (section)

===Chemical contamination===
In [[chemistry]], the term "contamination" usually describes a single constituent, but in specialized fields the term can also mean chemical mixtures, even up to the level of cellular materials. All chemicals contain some level of [[impurity]]. Contamination may be recognized or not and may become an issue if the impure chemical causes additional [[chemical reaction]]s when mixed with other chemicals or mixtures. Chemical reactions resulting from the presence of an impurity may at times be beneficial, in which case the label "contaminant" may be replaced with "[[reactant]]" or "[[catalyst]]." (This may be true even in physical chemistry, where, for example, the introduction of an impurity in an intrinsic semiconductor positively increases conductivity.<ref name="MoudgilText14">{{cite book |url=https://books.google.com/books?id=qWfkBQAAQBAJ&pg=PA278 |title=Textbook of Physical Chemistry |author=Moudgil, H.K. |publisher=PHI Learning |page=278 |year=2014 |isbn=9788120350625 |access-date=2019-04-12 |archive-date=2020-02-08 |archive-url=https://web.archive.org/web/20200208130129/https://books.google.com/books?id=qWfkBQAAQBAJ&pg=PA278 |url-status=live }}</ref>) If the additional reactions are detrimental, other terms are often applied such as "[[toxin]]", "[[poison]]", or [[pollutant]], depending on the type of [[molecule]] involved.<ref name="AltersBio00">{{cite book |url=https://books.google.com/books?id=GRDUIbQwGc8C&pg=PA828 |title=Biology: Understanding Life |author=Alters, S. |publisher=Jones & Bartlett Learning |page=828 |year=2000 |isbn=9780763708375 |access-date=2019-04-12 |archive-date=2020-02-08 |archive-url=https://web.archive.org/web/20200208130130/https://books.google.com/books?id=GRDUIbQwGc8C&pg=PA828 |url-status=live }}</ref> Chemical decontamination of substance can be achieved through decomposition, neutralization, and physical processes, though a clear understanding of the underlying chemistry is required.<ref name="MidcalfPharma04">{{cite book |url=https://books.google.com/books?id=XFaKhSPhoakC&pg=PA239 |title=Pharmaceutical Isolators: A Guide to Their Application, Design and Control |author=Midcalf, B. |publisher=Pharmaceutical Press |pages=88–89 |year=2004 |isbn=9780853695738 |access-date=2019-04-12 |archive-date=2020-02-08 |archive-url=https://web.archive.org/web/20200208130132/https://books.google.com/books?id=XFaKhSPhoakC&pg=PA239 |url-status=live }}</ref> Contamination of pharmaceutics and therapeutics is notoriously dangerous and creates both perceptual and technical challenges.<ref>{{Cite journal|last1=Abdin|first1=Ahmad Yaman|last2=Yeboah|first2=Prince|last3=Jacob|first3=Claus|date=January 2020|title=Chemical Impurities: An Epistemological Riddle with Serious Side Effects|journal=International Journal of Environmental Research and Public Health|language=en|volume=17|issue=3|pages=1030|doi=10.3390/ijerph17031030|pmc=7038150|pmid=32041209|doi-access=free}}</ref>