Mercury poisoning is a type of
metal poisoning due to exposure to
mercury.<a href="
https://en.wikipedia.org/wiki/Mercury_poisoning#cite_note-Ber2012-3"><span>[</span>3<span>]</span></a> Symptoms depend upon the type, dose, method, and duration of exposure.<a href="
https://en.wikipedia.org/wiki/Mercury_poisoning#cite_note-Ber2012-3"><span>[</span>3<span>]</span></a><a href="
https://en.wikipedia.org/wiki/Mercury_poisoning#cite_note-WHO2016-4"><span>[</span>4<span>]</span></a> They may include
muscle weakness, poor coordination,
numbness in the hands and feet, skin rashes, anxiety, memory problems, trouble speaking, trouble hearing, or trouble seeing.<a href="
https://en.wikipedia.org/wiki/Mercury_poisoning#cite_note-NIH2016-1"><span>[</span>1<span>]</span></a> High-level exposure to
methylmercury is known as
Minamata disease.<a href="
https://en.wikipedia.org/wiki/Mercury_poisoning#cite_note-Bos2010-2"><span>[</span>2<span>]</span></a> Methylmercury exposure in children may result in
acrodynia (pink disease) in which the skin becomes pink and peels.<a href="
https://en.wikipedia.org/wiki/Mercury_poisoning#cite_note-Bos2010-2"><span>[</span>2<span>]</span></a> Long-term complications may include
kidney problems and decreased intelligence.<a href="
https://en.wikipedia.org/wiki/Mercury_poisoning#cite_note-Bos2010-2"><span>[</span>2<span>]</span></a> The effects of long-term low-dose exposure to methylmercury are unclear.<a href="
https://en.wikipedia.org/wiki/Mercury_poisoning#cite_note-6"><span>[</span>6<span>]</span></a>
Forms of mercury exposure include
metal,
vapor,
salt, and
organic compound.<a href="
https://en.wikipedia.org/wiki/Mercury_poisoning#cite_note-Ber2012-3"><span>[</span>3<span>]</span></a> Most exposure is from
eating fish,
amalgam-based
dental fillings, or exposure at a workplace.<a href="
https://en.wikipedia.org/wiki/Mercury_poisoning#cite_note-Ber2012-3"><span>[</span>3<span>]</span></a> In fish, those higher up in the
food chain generally have higher levels of mercury, a process known as
biomagnification.<a href="
https://en.wikipedia.org/wiki/Mercury_poisoning#cite_note-Ber2012-3"><span>[</span>3<span>]</span></a> Less commonly, poisoning may occur as a method of attempted
suicide.<a href="
https://en.wikipedia.org/wiki/Mercury_poisoning#cite_note-Ber2012-3"><span>[</span>3<span>]</span></a> Human activities that release mercury into the environment include the burning of
coal and mining of
gold.<a href="
https://en.wikipedia.org/wiki/Mercury_poisoning#cite_note-WHO2016-4"><span>[</span>4<span>]</span></a><a href="
https://en.wikipedia.org/wiki/Mercury_poisoning#cite_note-7"><span>[</span>7<span>]</span></a> Tests of the blood, urine, and hair for mercury are available but do not relate well to the amount in the body.<a href="
https://en.wikipedia.org/wiki/Mercury_poisoning#cite_note-Ber2012-3"><span>[</span>3<span>]</span></a>
Prevention includes eating a diet low in mercury, removing mercury from medical and other devices, proper disposal of mercury, and not mining further mercury.<a href="
https://en.wikipedia.org/wiki/Mercury_poisoning#cite_note-WHO2016-4"><span>[</span>4<span>]</span></a><a href="
https://en.wikipedia.org/wiki/Mercury_poisoning#cite_note-Bos2010-2"><span>[</span>2<span>]</span></a> In those with acute poisoning from inorganic mercury salts,
chelation with either
dimercaptosuccinic acid (DMSA) or
dimercaptopropane sulfonate (DMPS) appears to improve outcomes if given within a few hours of exposure.<a href="
https://en.wikipedia.org/wiki/Mercury_poisoning#cite_note-Kos2013-5"><span>[</span>5<span>]</span></a> Chelation for those with long-term exposure is of unclear benefit.<a href="
https://en.wikipedia.org/wiki/Mercury_poisoning#cite_note-Kos2013-5"><span>[</span>5<span>]</span></a> In certain communities that survive on fishing, rates of mercury poisoning among children have been as high as 1.7 per 100.<a href="
https://en.wikipedia.org/wiki/Mercury_poisoning#cite_note-WHO2016-4"><span>[</span>4<span>]</span></a>
Signs and symptoms
Common symptoms of mercury poisoning are
peripheral neuropathy, presenting as
paresthesia or
itching, burning,
pain, or even a sensation that resembles small insects crawling on or under the skin (
formication); skin discoloration (pink cheeks, fingertips and toes); swelling;
desquamation (shedding or peeling of skin).<a href="
https://en.wikipedia.org/wiki/Mercury_poisoning#cite_note-8"><span>[</span>8<span>]</span></a> and the range of
neurological symptoms associated with
erethism.
Mercury irreversibly inhibits
selenium-dependent enzymes (see below) and may also inactivate
S-adenosyl methionine, which is necessary for
catecholamine catabolism by
catechol-O-methyltransferase. Due to the body's inability to degrade catecholamines (e.g.
adrenaline), a person with mercury poisoning may experience profuse
sweating,
tachycardia (persistently faster-than-normal heart beat), increased salivation, and
hypertension (high blood pressure).<a href="
https://en.wikipedia.org/wiki/Mercury_poisoning#cite_note-9"><span>[</span>9<span>]</span></a>
Affected children may show red
cheeks,
nose and lips, loss of
hair,
teeth, and
nails, transient rashes,
hypotonia (muscle weakness), and increased sensitivity to light. Other symptoms may include
kidney dysfunction (e.g.
Fanconi syndrome) or neuropsychiatric symptoms such as emotional
lability,
memory impairment, or
insomnia.<a href="
https://en.wikipedia.org/wiki/Mercury_poisoning#cite_note-10"><span>[</span>10<span>]</span></a>
Thus, the clinical presentation may resemble
pheochromocytoma or
Kawasaki disease. Desquamation (skin peeling) can occur with severe mercury poisoning acquired by handling elemental mercury.<a href="
https://en.wikipedia.org/wiki/Mercury_poisoning#cite_note-siblings-11"><span>[</span>11<span>]</span></a>