Editing Poison (section)

== Applications ==
Poisonous compounds may be useful either for their toxicity, or, more often, because of another chemical property, such as specific chemical reactivity. Poisons are widely used in industry and agriculture, as chemical reagents, solvents or complexing reagents, e.g. [[carbon monoxide]], [[methanol]] and [[sodium cyanide]], respectively. They are less common in household use, with occasional exceptions such as [[ammonia]] and [[methanol]]. For instance, [[phosgene]] is a highly reactive [[nucleophile]] acceptor, which makes it an excellent reagent for polymerizing [[diol]]s and [[diamine]]s to produce [[polycarbonate]] and [[polyurethane]] plastics. For this use, millions of tons are produced annually. However, the same reactivity makes it also highly reactive towards proteins in human tissue and thus highly toxic. In fact, phosgene has been used as a [[chemical weapon]]. It can be contrasted with [[sulfur mustard|mustard gas]], which has only been produced for chemical weapons uses, as it has no particular industrial use.

Biocides need not be poisonous to humans, because they can target metabolic pathways absent in humans, leaving only incidental toxicity. For instance, the herbicide [[2,4-dichlorophenoxyacetic acid]] is a mimic of a plant growth hormone, which causes uncontrollable growth leading to the death of the plant. Humans and animals, lacking this hormone and its receptor, are unaffected by this, and need to ingest relatively large doses before any toxicity appears. Human toxicity is, however, hard to avoid with pesticides targeting mammals, such as [[rodenticide]]s.

The risk from toxicity is also distinct from toxicity itself. For instance, the preservative [[thiomersal]] used in vaccines is toxic, but the quantity administered in a single shot is negligible.

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File:Poisonings world map-Deaths per million persons-WHO2012.svg|upright=1.3|Deaths from poisonings per million persons in 2012 {{Div col|small=yes|colwidth=10em}}{{leftlegend|#ffff20|0-2}}{{leftlegend|#ffe820|3-5}}{{leftlegend|#ffd820|6-7}}{{leftlegend|#ffc020|8-10}}{{leftlegend|#ffa020|11-12}}{{leftlegend|#ff9a20|13-19}}{{leftlegend|#f08015|20-27}}{{leftlegend|#e06815|28-41}}{{leftlegend|#d85010|42-55}}{{leftlegend|#d02010|56-336}}{{div col end}}
Image:Poisonings world map - DALY - WHO2004.svg|[[Disability-adjusted life year]] for poisonings per 100,000&nbsp;inhabitants in 2004.<ref>{{cite web |url=https://www.who.int/healthinfo/global_burden_disease/estimates_country/en/index.html |title=WHO Disease and injury country estimates |year=2004 |website=World Health Organization |access-date=Nov 11, 2009}}</ref>{{Div col|small=yes|colwidth=10em}}{{leftlegend|#b3b3b3|no data}}{{leftlegend|#ffff65|<10}}{{leftlegend|#fff200|10–90}}{{leftlegend|#ffdc00|90–170}}{{leftlegend|#ffc600|170–250}}{{leftlegend|#ffb000|250–330}}{{leftlegend|#ff9a00|330–410}}{{leftlegend|#ff8400|410–490}}{{leftlegend|#ff6e00|490–570}}{{leftlegend|#ff5800|570–650}}{{leftlegend|#ff4200|650–700}}{{leftlegend|#ff2c00|700–880}}{{leftlegend|#cb0000|>880}}{{div col end}}
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