Editing Cocaine (section)

===== Cocaine paste =====
{{Main|Cocaine paste}}
[[File:Precursor chemicals.gif|thumb|A cache of precursor chemicals near a South American cocaine processing lab]]

In traditional cocaine production, [[solvent]]s are key precursor chemicals used to extract and process cocaine from coca plant leaves. The process typically involves:
* [[Kerosene]] (or [[paraffin]]): Used to extract the cocaine alkaloid from the alkaline mixture of coca leaves and water.<ref name="EUDA" />
* [[Acetone]], [[diethyl ether]], [[ethyl acetate]], [[chloroform]]: Used in later purification steps to dissolve or precipitate cocaine base or hydrochloride.<ref name="EUDA" />

[[Cocaine paste]] (paco, basuco, oxi, pasta) is a crude extract of the [[coca leaf]] which contains 40% to 91% [[cocaine freebase]] along with companion coca alkaloids and varying quantities of [[benzoic acid]], [[methanol]], and [[kerosene]]. In South America, coca paste, also known as cocaine base and, therefore, often confused with cocaine sulfate in North America, is relatively inexpensive and is widely used by [[working class]] consumers. The coca paste is smoked in tobacco or cannabis cigarettes and use has become widespread in several Latin American countries. Traditionally, coca paste has been relatively abundant in [[List of sovereign states and dependent territories in South America|South American countries]] such as Colombia where it is processed into cocaine hydrochloride ("street cocaine") for distribution to the rest of the world.<ref name="a">{{citation | editor1=Nicholas J. Kozel | editor2=Edgar H. Adams | author=Ronald K. Siegel | author-link=Ronald K. Siegel | contribution=New Patterns of Cocaine Use: Changing Doses and Routes | title=Cocaine Use in America: Epidemiologic and Clinical Perspectives | series=NIDA Research Monograph | volume=61 | year=1985 | publisher=U.S. Dept. of Health and Human Services | pages=204–222 | url=http://archives.drugabuse.gov/pdf/monographs/61.pdf | access-date=9 April 2016 | archive-url=https://web.archive.org/web/20161009021412/http://archives.drugabuse.gov/pdf/monographs/61.pdf | archive-date=9 October 2016 | url-status=dead }}</ref> The caustic reactions associated with the local application of coca paste prevents its use by oral, intranasal, mucosal, or [[Injection (medicine)|injection]] routes. Coca paste can only be smoked when combined with a combustible material such as tobacco or cannabis.<ref name="f">{{citation | editor=A. Arif | title=Adverse health consequences of cocaine abuse | publisher=World Health Organization | year=1987 | url=http://apps.who.int/iris/bitstream/10665/37270/1/9241561076.pdf}}</ref>

An interview with a coca farmer published in 2003 described a mode of production by [[acid-base extraction]] that has changed little since 1905. Roughly {{convert|625|lb|kg}} of leaves were harvested per [[hectare]], six times per year. The leaves were dried for half a day, then chopped into small pieces with a string trimmer and sprinkled with a small amount of powdered cement (replacing [[sodium carbonate]] from former times). Several hundred pounds of this mixture were soaked in {{convert|50|USgal|L}} of gasoline for a day, then the gasoline was removed and the leaves were pressed for the remaining liquid, after which they could be discarded. Then [[battery acid]] (weak [[sulfuric acid]]) was used, one bucket per {{convert|25|kg|0|abbr=on|order=flip}} of leaves, to create a [[phase (matter)|phase]] separation in which the cocaine [[free base]] in the gasoline was acidified and extracted into a few buckets of "murky-looking smelly liquid". Once powdered [[caustic soda]] was added to this, the cocaine precipitated and could be removed by filtration through a cloth. The resulting material, when dried, was termed ''[[cocaine paste|pasta]]'' and sold by the farmer. The {{convert|3,750|lb}} yearly harvest of leaves from a hectare produced {{convert|2.5|kg|0|abbr=on|order=flip}} of ''pasta''<!--- note that this figure is only about ⅓ of the figure inferred from the numbers below --->, approximately 40–60% cocaine. Repeated recrystallization from solvents, producing ''pasta lavada'' and eventually crystalline cocaine were performed at specialized laboratories after the sale.<ref>{{Cite book|url=https://books.google.com/books?id=9ceLzaeHsZAC&pg=PA462|title=Cocaine: An Unauthorized Biography | vauthors = Streatfeild D |publisher=Macmillan|year=2003|isbn=978-0-312-42226-4|access-date=5 January 2014|url-status=live|archive-url=https://web.archive.org/web/20140115082648/https://books.google.com/books?id=9ceLzaeHsZAC&pg=PA462|archive-date=15 January 2014}}</ref>