Epsom Salts

Magnesium sulfate (or magnesium sulphate) is a <a href="http://en.wikipedia.org/wiki/Chemical_compound" title="Chemical compound">chemical compound</a> containing <a href="http://en.wikipedia.org/wiki/Magnesium" title="Magnesium">magnesium</a>, <a href="http://en.wikipedia.org/wiki/Sulfur" title="Sulfur">sulfur</a> and <a href="http://en.wikipedia.org/wiki/Oxygen" title="Oxygen">oxygen</a>, with the formula MgSO4. It is often encountered as the heptahydrate <a href="http://en.wikipedia.org/wiki/Epsomite" title="Epsomite">epsomite</a> (MgSO4·7H2O), commonly called Epsom salt, from the town of <a href="http://en.wikipedia.org/wiki/Epsom" title="Epsom">Epsom</a> in <a href="http://en.wikipedia.org/wiki/Surrey" title="Surrey">Surrey</a>, England, where the salt was distilled from the springs that arise where the porous chalk of the <a href="http://en.wikipedia.org/wiki/North_Downs" title="North Downs">North Downs</a> meets non-porous London clay. Another <a href="http://en.wikipedia.org/wiki/Hydrate" title="Hydrate">hydrate</a> form is <a href="http://en.wikipedia.org/wiki/Kieserite" title="Kieserite">kieserite</a>.

<a href="http://en.wikipedia.org/wiki/Anhydrous" title="Anhydrous">Anhydrous</a> magnesium sulfate is used as a drying agent. Since the anhydrous form is <a href="http://en.wikipedia.org/wiki/Hygroscopic" title="Hygroscopic" class="mw-redirect">hygroscopic</a> (readily absorbs water from the air) and is therefore difficult to weigh accurately, the hydrate is often preferred when preparing solutions, for example in medical preparations. Epsom salt has been traditionally used as a component of <a href="http://en.wikipedia.org/wiki/Bath_salts" title="Bath salts">bath salts</a>.

<h2>Properties</h2>

Magnesium sulfate is the primary substance that causes the absorption of <a href="http://en.wikipedia.org/wiki/Underwater_acoustics" title="Underwater acoustics">sound</a> in <a href="http://en.wikipedia.org/wiki/Seawater" title="Seawater">seawater</a>.<a href="http://en.wikipedia.org/wiki/Epsom_salts#cite_note-0">[1]</a> Absorption, in this case, means the conversion of acoustic energy to heat energy. The conversion is a strong function of frequency. Lower frequencies are less affected by the <a href="http://en.wikipedia.org/wiki/Salt_%28chemistry%29" title="Salt (chemistry)">salt</a>, so that the acoustic energy travels much farther in the ocean. <a href="http://en.wikipedia.org/wiki/Boric_acid" title="Boric acid">Boric acid</a> also contributes to absorption; but the most abundant salt in seawater, <a href="http://en.wikipedia.org/wiki/Sodium_chloride" title="Sodium chloride">sodium chloride</a>, has no known effect on sound absorption.

<h2>[<a href="http://en.wikipedia.org/w/index.php?title=Magnesium_sulfate&action=edit&section=2" title="Edit section: Hydrates">edit</a>] Hydrates</h2>

Almost all known mineralogical forms of MgSO4 occur as hydrates. <a href="http://en.wikipedia.org/wiki/Epsomite" title="Epsomite">Epsomite</a> is the natural analogue of "Epsom salt". Another heptahydrate, the <a href="http://en.wikipedia.org/wiki/Copper" title="Copper">copper</a>-containing mineral alpersite (Mg,Cu)SO4·7H2O,<a href="http://en.wikipedia.org/wiki/Epsom_salts#cite_note-1">[2]</a> was also recently recognized. Both are however not the highest known hydrates of MgSO4, due to the recent terrestrial find of <a href="http://en.wikipedia.org/wiki/Meridianiite" title="Meridianiite">meridianiite</a>, MgSO4·11H2O, which is thought to also occur on Mars. <a href="http://en.wikipedia.org/w/index.php?title=Hexahydrite&action=edit&redlink=1" class="new" title="Hexahydrite (page does not exist)">Hexahydrite</a> is the next lower (6) hydrate. Three next lower hydrates - <a href="http://en.wikipedia.org/w/index.php?title=Pentahydrite&action=edit&redlink=1" class="new" title="Pentahydrite (page does not exist)">pentahydrite</a> (5), <a href="http://en.wikipedia.org/w/index.php?title=Starkeyite&action=edit&redlink=1" class="new" title="Starkeyite (page does not exist)">starkeyite</a> (4) and especially <a href="http://en.wikipedia.org/w/index.php?title=Sanderite&action=edit&redlink=1" class="new" title="Sanderite (page does not exist)">sanderite</a> (2) are more rarely found. <a href="http://en.wikipedia.org/wiki/Kieserite" title="Kieserite">Kieserite</a> is a monohydrate and is common among evaporitic deposits. Anhydrous magnesium sulfate was reported from some burning coal dumps, but never treated as a mineral.

The pH of hydrates is average 6.0 (5.5 to 6.5). Magnesium <a href="http://en.wikipedia.org/wiki/Hydrate" title="Hydrate">hydrates</a> have, like <a href="http://en.wikipedia.org/wiki/Copper%28II%29_sulfate" title="Copper(II) sulfate">Copper(II) sulfate</a>, <a href="http://en.wikipedia.org/wiki/Coordinated_water" title="Coordinated water" class="mw-redirect">coordinated water</a>.<a href="http://en.wikipedia.org/wiki/Epsom_salts#cite_note-2">[3]</a>

<h2>[<a href="http://en.wikipedia.org/w/index.php?title=Magnesium_sulfate&action=edit&section=3" title="Edit section: Occurrence">edit</a>] Occurrence</h2>

Magnesium sulfates are common minerals in geological environments. Their occurrence is mostly connected with <a href="http://en.wikipedia.org/wiki/Supergene_%28geology%29" title="Supergene (geology)">supergene</a> processes. Some of them are also important constituents of evaporitic <a href="http://en.wikipedia.org/wiki/Potassium" title="Potassium">potassium</a>-magnesium (K-Mg) salts deposits.

<h2>[<a href="http://en.wikipedia.org/w/index.php?title=Magnesium_sulfate&action=edit&section=4" title="Edit section: Applications">edit</a>] Applications</h2>

In <a href="http://en.wikipedia.org/wiki/Agriculture" title="Agriculture">agriculture</a> and <a href="http://en.wikipedia.org/wiki/Gardening" title="Gardening">gardening</a>, magnesium sulfate is used to correct magnesium deficiency in <a href="http://en.wikipedia.org/wiki/Soil" title="Soil">soil</a>, since magnesium is an essential element in the <a href="http://en.wikipedia.org/wiki/Chlorophyll" title="Chlorophyll">chlorophyll</a> molecule. It is most commonly applied to potted plants, or to magnesium-hungry crops, such as <a href="http://en.wikipedia.org/wiki/Potato" title="Potato">potatoes</a>, <a href="http://en.wikipedia.org/wiki/Rose" title="Rose">roses</a>, <a href="http://en.wikipedia.org/wiki/Tomato" title="Tomato">tomatoes</a>, <a href="http://en.wikipedia.org/wiki/Capsicum" title="Capsicum">peppers</a> and <a href="http://en.wikipedia.org/wiki/Cannabis" title="Cannabis">cannabis</a>. The advantage of magnesium sulfate over other magnesium <a href="http://en.wikipedia.org/wiki/Soil_amendment" title="Soil amendment" class="mw-redirect">soil amendments</a> (such as <a href="http://en.wikipedia.org/wiki/Dolomite" title="Dolomite">dolomitic lime</a>) is its high <a href="http://en.wikipedia.org/wiki/Solubility" title="Solubility">solubility</a>.

<a href="http://en.wikipedia.org/wiki/Anhydrous" title="Anhydrous">Anhydrous</a> magnesium sulfate is commonly used as a <a href="http://en.wikipedia.org/wiki/Desiccant" title="Desiccant">desiccant</a> in organic synthesis due to its affinity for water. During <a href="http://en.wikipedia.org/wiki/Work-up" title="Work-up">work-up</a>, an organic phase is saturated with magnesium sulfate until it no longer forms clumps. The hydrated solid is then removed with filtration or decantation. Other inorganic sulfate salts such as <a href="http://en.wikipedia.org/wiki/Sodium_sulfate" title="Sodium sulfate">sodium sulfate</a> and <a href="http://en.wikipedia.org/wiki/Calcium_sulfate" title="Calcium sulfate">calcium sulfate</a> may also be used in the same way.

Magnesium sulfate is used in <a href="http://en.wikipedia.org/wiki/Bath_salts" title="Bath salts">bath salts</a>, particularly in <a href="http://en.wikipedia.org/wiki/Isolation_tank" title="Isolation tank">flotation therapy</a> where high concentrations raise the bath water's <a href="http://en.wikipedia.org/wiki/Specific_gravity" title="Specific gravity">specific gravity</a>, effectively making the body more buoyant. Traditionally, it is also used to prepare foot baths, intended to soothe sore feet. The reason for the inclusion of the salt is partially cosmetic: the increase in ionic strength prevents some of the temporary skin wrinkling ("pruning" – partial maceration) which is caused by prolonged immersion of extremities in pure water. However, magnesium sulfate can also be absorbed into the skin, reducing inflammation. It is also sometimes found in bottled mineral water, and accordingly is sometimes listed in the contents thereof.[<a href="http://en.wikipedia.org/wiki/Wikipedia:Citation_needed" title="Wikipedia:Citation needed">citation needed</a>]

It may also be used as a coagulant for making <a href="http://en.wikipedia.org/wiki/Tofu" title="Tofu">tofu</a>.<a href="http://en.wikipedia.org/wiki/Epsom_salts#cite_note-3">[4]</a>

Magnesium sulfate heptahydrate is also used to maintain the magnesium concentration in marine aquaria which contain large amounts of stony corals as it is slowly depleted in their calcification process. In a magnesium-deficient marine aquarium calcium and alkalinity concentrations are very difficult to control because not enough magnesium is present to stabilize these ions in the saltwater and prevent their spontaneous precipitation into calcium carbonate.<a href="http://en.wikipedia.org/wiki/Epsom_salts#cite_note-4">[5]</a>

Magnesium sulfate is used as a reactive compound in the manufacture of <a href="http://en.wikipedia.org/wiki/Black_powder" title="Black powder" class="mw-redirect">black powder</a> where it contributes to a violent burn rate thus reducing material costs.[<a href="http://en.wikipedia.org/wiki/Wikipedia:Citation_needed" title="Wikipedia:Citation needed">citation needed</a>]

Magnesium sulfate is used as the electrolyte to prepare copper sulfate. A magnesium sulfate solution is electrolyzed with a copper anode to form copper sulfate, magnesium hydroxide, and hydrogen:

<dl>

<dd>Cu + MgSO4 + 2 H2O → H2 + CuSO4 + Mg(OH)2.[<a href="http://en.wikipedia.org/wiki/Wikipedia:Citation_needed" title="Wikipedia:Citation needed">citation needed</a>]</dd>

</dl>

Magnesium sulfate is used as a brewing salt in beer production to adjust the ion content of the brewing water and enhance enzyme action in the mash or promote a desired flavor profile in the beer.

<h3>[<a href="http://en.wikipedia.org/w/index.php?title=Magnesium_sulfate&action=edit&section=5" title="Edit section: Medical use">edit</a>] Medical use</h3>

<div class="rellink boilerplate further">Further information: <a href="http://en.wikipedia.org/wiki/Hypomagnesemia" title="Hypomagnesemia">Hypomagnesemia</a></div>

Oral magnesium sulfate is commonly used as a <a href="http://en.wikipedia.org/wiki/Salinity" title="Salinity">saline</a> <a href="http://en.wikipedia.org/wiki/Laxative" title="Laxative">laxative</a> or osmotic purgatives. Epsom salt is also available in a gel form for topical application in treating aches and pains.

Indications for its internal use are:

<ul>

<li>Replacement therapy for <a href="http://en.wikipedia.org/wiki/Hypomagnesemia" title="Hypomagnesemia">hypomagnesemia</a>.<a href="http://en.wikipedia.org/wiki/Epsom_salts#cite_note-5">[6]</a></li>

<li>Magnesium sulfate is the first-line antiarrhythmic agent for <a href="http://en.wikipedia.org/wiki/Torsades_de_pointes" title="Torsades de pointes">torsades de pointes</a> in <a href="http://en.wikipedia.org/wiki/Cardiac_arrest" title="Cardiac arrest">cardiac arrest</a> under the 2005 ECC guidelines and for managing <a href="http://en.wikipedia.org/wiki/Quinidine" title="Quinidine">quinidine</a>-induced arrhythmias.<a href="http://en.wikipedia.org/wiki/Epsom_salts#cite_note-6">[7]</a></li>

<li>As a <a href="http://en.wikipedia.org/wiki/Bronchodilator" title="Bronchodilator">bronchodilator</a> after beta-agonist and <a href="http://en.wikipedia.org/wiki/Anticholinergic" title="Anticholinergic">anticholinergic</a> agents have been tried, e.g. in severe exacerbations of <a href="http://en.wikipedia.org/wiki/Asthma" title="Asthma">asthma</a>.<a href="http://en.wikipedia.org/wiki/Epsom_salts#cite_note-blitz-7">[8]</a> Recent studies have revealed that magnesium sulfate can be nebulized to reduce the symptoms of acute asthma.<a href="http://en.wikipedia.org/wiki/Epsom_salts#cite_note-blitz-7">[8]</a> It is commonly administered via the <a href="http://en.wikipedia.org/wiki/Intravenous" title="Intravenous" class="mw-redirect">intravenous</a> route for the management of severe <a href="http://en.wikipedia.org/wiki/Asthma" title="Asthma">asthma</a> attacks.</li>

<li>Magnesium sulfate can be used to treat <a href="http://en.wikipedia.org/wiki/Eclampsia" title="Eclampsia">eclampsia</a> in pregnant women.<a href="http://en.wikipedia.org/wiki/Epsom_salts#cite_note-8">[9]</a></li>

<li>Magnesium sulfate can also delay labor in the case of premature labor, to delay <a href="http://en.wikipedia.org/wiki/Preterm_birth" title="Preterm birth">preterm birth</a>.<a href="http://en.wikipedia.org/wiki/Epsom_salts#cite_note-9">[10]</a><a href="http://en.wikipedia.org/wiki/Epsom_salts#cite_note-pmid16125045-10">[11]</a></li>

<li><a href="http://en.wikipedia.org/wiki/Intravenous" title="Intravenous" class="mw-redirect">Intravenous</a> magnesium sulfate may be able to prevent <a href="http://en.wikipedia.org/wiki/Cerebral_palsy" title="Cerebral palsy">cerebral palsy</a> in <a href="http://en.wikipedia.org/wiki/Preterm" title="Preterm" class="mw-redirect">preterm</a> babies.<a href="http://en.wikipedia.org/wiki/Epsom_salts#cite_note-11">[12]</a></li>

<li>Solutions of sulfate salts such as Epsom salt may be given as first aid for <a href="http://en.wikipedia.org/wiki/Barium_chloride" title="Barium chloride">barium chloride</a> poisoning.<a href="http://en.wikipedia.org/wiki/Epsom_salts#cite_note-12">[13]</a></li>

</ul>

Indications for topical use are

<ul>

<li>Soaking in a warm bath containing Epsom salt (magnesium sulfate) can be beneficial to soothe, relax, and relieve herpes outbreak symptoms, such as itching and lesions relating to <a href="http://en.wikipedia.org/wiki/Genital_herpes" title="Genital herpes" class="mw-redirect">genital herpes</a> and <a href="http://en.wikipedia.org/wiki/Shingles" title="Shingles" class="mw-redirect">shingles</a>.<a href="http://en.wikipedia.org/wiki/Epsom_salts#cite_note-13">[14]</a><a href="http://en.wikipedia.org/wiki/Epsom_salts#cite_note-14">[15]</a></li>

<li>A 2004 research study showed that both magnesium and sulfate are absorbed through the skin when bathing in 1% <a href="http://en.wikipedia.org/wiki/W/v" title="W/v" class="mw-redirect">w/v</a> solution.<a href="http://en.wikipedia.org/wiki/Epsom_salts#cite_note-15">[16]</a></li>

</ul>

<ul>

</ul>