Tetrasodium Pyrophosphate
<p ><b>Tetrasodium pyrophosphate</b>, also called <b>sodium pyrophosphate</b>, <b>tetrasodium phosphate</b> or TSPP, is a<a href="http://en.wikipedia.org/wiki/Color" title="Color" >colorless</a> <a href="http://en.wikipedia.org/wiki/Transparency_(optics)" title="Transparency (optics)" class="mw-redirect" >transparent</a> <a href="http://en.wikipedia.org/wiki/Crystalline" title="Crystalline" class="mw-redirect" >crystalline</a> <a href="http://en.wikipedia.org/wiki/Chemical_compound" title="Chemical compound" >chemical compound</a> with the <a href="http://en.wikipedia.org/wiki/Chemical_formula" title="Chemical formula" >formula</a> Na<sub >4</sub>P<sub >2</sub>O<sub >7</sub>. It contains the <a href="http://en.wikipedia.org/wiki/Pyrophosphate" title="Pyrophosphate" >pyrophosphate</a> <a href="http://en.wikipedia.org/wiki/Ion" title="Ion" >ion</a>and <a href="http://en.wikipedia.org/wiki/Sodium" title="Sodium" >sodium</a> <a href="http://en.wikipedia.org/wiki/Cation" title="Cation" class="mw-redirect" >cation</a>. </p>
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Toxicity is approximately twice that of <a href="http://en.wikipedia.org/wiki/Table_salt" title="Table salt" class="mw-redirect" >table salt</a> when ingested orally.<sup id="cite_ref-0" class="reference" ><a href="http://en.wikipedia.org/wiki/Tetrasodium_pyrophosphate#cite_note-0" >[1]</a></sup> </p>
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There is also a hydrated form, Na<sub >4</sub>P<sub >2</sub>O<sub >7</sub> · 10(H<sub >2</sub>O).<sup id="cite_ref-Perry_1-0" class="reference" ><a href="http://en.wikipedia.org/wiki/Tetrasodium_pyrophosphate#cite_note-Perry-1" >[2]</a></sup></p>
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Sodium pyrophosphate is used as a <a href="http://en.wikipedia.org/wiki/Buffering_agent" title="Buffering agent" >buffering agent</a>, an <a href="http://en.wikipedia.org/wiki/Emulsifier" title="Emulsifier" class="mw-redirect" >emulsifier</a>, a dispersing agent, and a <a href="http://en.wikipedia.org/wiki/Thickening_agent" title="Thickening agent" >thickening agent</a>, and is often used as a <a href="http://en.wikipedia.org/wiki/Food_additive" title="Food additive" >food additive</a>.</p>
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Common <a href="http://en.wikipedia.org/wiki/Food" title="Food" >foods</a> containing sodium pyrophosphate include
<a href="http://en.wikipedia.org/wiki/Chicken_nugget" title="Chicken nugget" >chicken nuggets</a>,<a href="http://en.wikipedia.org/wiki/Marshmallows" title="Marshmallows" class="mw-redirect" >marshmallows</a>, <a href="http://en.wikipedia.org/wiki/Pudding" title="Pudding" >pudding</a>, <a href="http://en.wikipedia.org/wiki/Crab" title="Crab" >crab</a> meat, <a href="http://en.wikipedia.org/wiki/Imitation_crab" title="Imitation crab" class="mw-redirect" >imitation crab</a>, canned <a href="http://en.wikipedia.org/wiki/Tuna" title="Tuna" >tuna</a>, and <a href="http://en.wikipedia.org/wiki/Soy" title="Soy" class="mw-redirect" >soy</a>-based <a href="http://en.wikipedia.org/wiki/Meat" title="Meat" >meat</a> alternatives and <a href="http://en.wikipedia.org/wiki/Cat_food" title="Cat food" >cat foods</a> and cat treats where it is used as a <a href="http://en.wikipedia.org/wiki/Palatability" title="Palatability" >palatability</a> enhancer. </p>
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It is the active ingredient in Bakewell, the substitute for baking powder's acid component marketed during shortages in World War II. It is also used in some common <a href="http://en.wikipedia.org/wiki/Baking_powder" title="Baking powder" >baking powders</a>.</p>
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In <a href="http://en.wikipedia.org/wiki/Toothpaste" title="Toothpaste" >toothpaste</a> and dental floss, sodium pyrophosphate acts as a <a href="http://en.wikipedia.org/wiki/Calculus_(dental)" title="Calculus (dental)" >tartar</a> control agent, serving to remove <a href="http://en.wikipedia.org/wiki/Calcium" title="Calcium" >calcium</a> and <a href="http://en.wikipedia.org/wiki/Magnesium" title="Magnesium" >magnesium</a> from <a href="http://en.wikipedia.org/wiki/Saliva" title="Saliva" >saliva</a> and thus preventing them from being deposited on <a href="http://en.wikipedia.org/wiki/Teeth" title="Teeth" class="mw-redirect" >teeth</a>.</p>
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Sodium pyrophosphate is sometimes used in household <a href="http://en.wikipedia.org/wiki/Detergent" title="Detergent" >detergents</a> to prevent
similar deposition on <a href="http://en.wikipedia.org/wiki/Clothing" title="Clothing" >clothing</a>, but due to its <a href="http://en.wikipedia.org/wiki/Phosphate" title="Phosphate" >phosphate</a> content it causes <a href="http://en.wikipedia.org/wiki/Eutrophication" title="Eutrophication" >eutrophication</a> of <a href="http://en.wikipedia.org/wiki/Water" title="Water" >water</a>, promoting <a href="http://en.wikipedia.org/wiki/Algae" title="Algae" >algae</a> growth.</p>
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<a href="http://en.wikipedia.org/wiki/Calcium_pyrophosphate" title="Calcium pyrophosphate" >Calcium pyrophosphate</a> is the crystal deposited in joints in the
medical condition <a href="http://en.wikipedia.org/wiki/Pseudogout" title="Pseudogout" class="mw-redirect" >pseudogout</a>.<sup id="cite_ref-2" class="reference" ><a href="http://en.wikipedia.org/wiki/Tetrasodium_pyrophosphate#cite_note-2" >[3]</a></sup></p>