Mercury poisoning

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Classification according to ICD-10
T56.1 Toxic effect: mercury and its compounds
ICD-10 online (WHO version 2019)

A mercury poisoning (Merkurialismus) is a poisoning with the toxic heavy metal mercury , such as in the form of corrosive sublimate (HgCl 2 ), mercuric cyanide (Hg (CN) 2 ) or Quecksilberoxycyanat (Hg (CN) 2 + HgO). The poisoning is caused by the direct absorption of the vapors of the mercury. One speaks of acute poisoning. Chronic poisoning is also possible if one is exposed to small amounts over a long period of time ( Minamata disease ).

Mercury is liquid at room temperature and normal pressure and in this physical state is still relatively harmless. However, at room temperature, liquid mercury slowly evaporates and forms toxic fumes . Organic compounds of mercury, especially methyl mercury, which are particularly toxic . B. is formed in the organism of fish from mercury.

Mercury Emission Sources

Small amounts of mercury can come into contact in private households if mercury-containing thermometers and compact fluorescent lamps break. ( In this case, the Federal Environment Agency advises sweeping up in a closed glass and particularly intensive ventilation.) Modern expansion thermometers are mercury-free and usually filled with harmless ethanol .

Much larger mercury emissions arise from the combustion of coal and the extraction of natural gas. The energy sector is charged with a share of 70% of total German mercury emissions.

The long-term effect of wearing amalgam dental seals is controversial. A short-term increased exposure to mercury vapor results from high-speed, unprotected drilling out of dental amalgam ; protection by a latex membrane placed over the throat in conjunction with suction is possible.

Mercury is used in gold extraction (amalgam process) and is released in large quantities in small mines and when panning for gold , e.g. B. in the Amazon region of Brazil and Peru . Other major sources of mercury emissions are combustion and smelting processes, especially coal firing , cement kilns , copper / lead / zinc smelters and waste incineration (see UN Minamata Convention on Mercury Reduction ).

Effect of mercury on the organism

This article or the following section is not adequately provided with supporting documents ( e.g. individual evidence ). Information without sufficient evidence could be removed soon. Please help Wikipedia by researching the information and including good evidence.

Elemental liquid mercury is as good as not absorbed at all by the human body. This applies to both skin contact and the ingestion of mercury. In the Middle Ages, mercury was used to treat intestinal obstruction. The absorption rate is extremely low (between 0.001 and 0.01 percent), and a large part of the elemental mercury is excreted very quickly.

Significantly more problematic are mercury vapors with absorption rates in the region of 1 percent.

On the other hand, mercury ions (Hg 2+ ions) and organic compounds of mercury are extremely toxic . These are almost 100 percent absorbed and only excreted after months and years. Furthermore, what makes these compounds dangerous is that they can easily cross the blood-brain barrier . The best known are mono- methylmercury and di-methylmercury with a mean lethal dose of 30 mg / kg and 1 mg / kg.

When these ions enter the bloodstream, they can have various toxic effects. This includes, for example, the methylation of mercury by methyltransferases . As a result, the organism damages itself by building up a strong poison ( dimethylmercury ), which can also be transported better through membranes than mercury itself. This enables it to spread quickly in the body.

In addition, mercury ions have a high affinity for sulfur, which is mainly found in proteins . Mercury destroys proteins through interactions with their sulfur atoms, so it splits disulfide bridges , which are indispensable for the complex structure and thus the function of proteins. Nerve tissue in particular is severely affected by the latter interaction, resulting in the symptoms listed below (disturbance of the CNS function).

Guide values ​​from the German Federal Environment Agency for mercury in indoor air

Guide values ​​for mercury (as metallic vapor) in indoor air according to the German Federal Environment Agency (as of 1999)
Guide value II
in µg / m³ 		Guide value I
in µg / m³
0.35 0.035

Indoor air guide values ​​for individual substances are worked out by an ad hoc working group consisting of members of the Indoor Air Hygiene Commission (IRK) at the German Federal Environment Agency and the Working Group of the Supreme State Health Authorities ( AOLG ). A distinction is made between two guide value categories:

  • Guide value II (RW II) is an effect-related value that is based on the current toxicological and epidemiological knowledge of the effect threshold of a substance with the introduction of uncertainty factors. It represents the concentration of a substance, which must be acted upon immediately when it is reached or exceeded. This higher concentration can be a health hazard, especially for sensitive people who stay in the rooms for a long time. Depending on the mode of action of the substance, the reference value II can be defined as a short-term value (RW II K) or a long-term value (RW II L).
  • Guide value I (RW I - precautionary value) describes the concentration of a substance in the indoor air at which, according to the current state of knowledge, no health impairment is to be expected when considering individual substances even if a person is exposed to this substance for life. However, if it is exceeded, it is associated with an undesirable load that goes beyond the usual level. For reasons of precaution, action should also be taken in the concentration range between reference values ​​I and II, be it through technical and structural measures on the building (in this case the building operator must act) or through changed user behavior. Guide value I can serve as a target value for the renovation.

Acute poisoning

Acute heavy metal poisoning is mostly due to accidents. So far, only about ten cases of acute fatal mercury poisoning have become known around the world. The victims were in tanks containing mercury or were standing next to hot mercury under unfavorable conditions. A famous example of acute dimethyl mercury poisoning is the American researcher Karen Wetterhahn . She began to experience symptoms months after the accident at work, which she only then remembered. Almost a year later she died of the consequences. An initially puzzling case of acute poisoning with methyl mercury in Germany in 2016 turned out to be a forensic case.

The first symptoms of acute poisoning are:

  • a headache
  • nausea
  • dizziness
  • dry mouth and throat

A doctor must be consulted immediately , as the damage is usually irreparable if countermeasures are not taken immediately. An amount of 150 to 300 mg is considered fatal  . Long-term damage is often kidney and liver damage .

An acute short-term exposure to mercury is not a cause for health concern under the conditions of a broken mercury-containing thermometer or an energy-saving lamp in the home. If the mercury thermometer is broken, the amount of vapors emitted is likely to be too small to cause acute or chronic symptoms of poisoning. The solid mercury amalgam used for compact fluorescent lamps only releases around a tenth of that of liquid mercury. The authorities do not see any dangers from acute, but only from chronic, i.e. permanent exposure. The alternative LED lamps do not release any mercury if they are destroyed.

Based on extensive safety investigations for the 20,000 kg mercury-operated spallation neutron source SNS in the USA, the American environmental authority EPA first published guideline values ​​(Acute exposure guideline level AEGL) for acute poisoning with mercury vapor in 2010.

Chronic poisoning

Chronic poisoning caused by small doses of mercury that is ingested through food ( Minamata disease ) is much more common . If mercury is spilled in a closed room, it can seep away and form toxic fumes for a long time. The in dentistry used amalgam is controversial as another cause of chronic mercury poisoning: Some scientists point to its vulnerability to processing errors, others gradually it as harmless.

One of the historically best-known examples of chronic mercury poisoning is the Slovenian city of Idrija , where the world's second largest mercury mine stood until it was closed in the 20th century. The famous doctor Paracelsus already reported in 1527 about the sick population “see an example in Idria; everyone who lives there is crooked and lame. ”The situation only improved at the end of the 18th century thanks to improved processing methods.

In the 18th century, chronic poisoning occurred in some occupational groups who frequently had to deal with mercury and mercury salts (→ " hat maker syndrome "). At that time many and often used drugs containing mercury were still being produced. Mercury salts are used today only as the "basic substance" of homeopathic products. As a preservative, mercury-containing thimerosal is still used in eye drops and a few vaccines.

In 1889, Prussia and Bavaria issued regulations on the production of mercury mirrors to protect workers from chronic poisoning. A famous example of chronic poisoning is the German chemist Alfred Stock , who had a lot of inorganic mercury in his laboratory. With an article on the dangers of mercury vapor , he sparked a "polemical exchange of blows between oppositely-minded scientists" in the 1920s.

Possible causes of chronic poisoning are the ingestion of mercury at home, at work, through food or through dental metal.

After accidents (for example with old clinical thermometers with mercury, broken fluorescent lamps or energy-saving lamps) or due to bleach, there is usually only one-time or short-term exposure. Chronic poisoning can only be caused with regular exposure.

Findings of mercury in the human body:

In pregnant women, the poison passes through the umbilical vein to the fetus . In Minamata , many infants with disabilities were born after their mothers consumed methylmercury- contaminated fish. The consumption of sea fish increases the mercury exposure of the fetus. The effects of low exposure from fish consumption are unclear. Even low doses of mercury get into the fetus if the mother has amalgam fillings . The amount of mercury in umbilical cord blood and children's brains correlates with the number of amalgam fillings the mothers have. At a mercury concentration of 7 µg / g, reactive astrogliosis occurs at the cellular level in the fetal brain , although there are no more detailed studies of the effects of this exposure in vivo .

Therapy of mercury poisoning

Mercury poisoning is treated with an antidote ("antidote"). So-called complexing agents are used , i.e. substances that form a metal complex with mercury as the central atom. These complexes can be filtered from the blood by the kidneys much more easily. Above all, the more water-soluble dimercaptopropane sulfonic acid (DMPS) and (sometimes with cerebral infestation) dimercaptosuccinic acid (DMSA) are used. These two substances have two adjacent sulfhydryl groups (-SH), which form stable chelate complexes with the mercury atom .

Acetylcysteine (NAC) is effective in animal experiments for methylmercury poisoning . In contrast to the chelating agents DMPS and DMSA, it does not interfere with the mineral balance. It has no effect against inorganic mercury; its use is not recommended by specialist societies.

The use of minerals for mercury removal is not medically established. There is no clear evidence of a medical benefit for the use of zinc as an antidote to mercury poisoning. Selenium (added as sodium selenite in animal experiments) reduces the effectiveness of the antidotes DMSA and DMPS, but overall there is no evidence of a benefit in humans when used against mercury poisoning.

However, selenium is necessary for the body's own defense mechanisms: "A key element of the cellular defense mechanisms is the availability of selenium and of SH groups that can chelate mercury ".

Individual evidence

  1. ^ Helmut Schubothe: Poisonings. In: Ludwig Heilmeyer (ed.): Textbook of internal medicine. Springer-Verlag, Berlin / Göttingen / Heidelberg 1955; 2nd edition, ibid. 1961, pp. 1195-1217, here: pp. 1207 f. ( Mercury poisoning ).
  2. ↑ Energy-saving lamps: When they break, ventilation is essential. Press release, Federal Environment Agency, Dessau, August 25, 2011.
  3. ↑ New report: Discussion about the danger of mercury from coal-fired power plants. Spiegel Online, May 2, 2014, accessed December 1, 2014 .
  4. ↑ Hermann Bubke: Study on the contamination of workers with mercury during natural gas production in the Altmark. (PDF) October 2010, accessed December 1, 2014 .
  5. ↑ Thorsten Knuf: coal power plants: nerve poison from the chimney. In: Frankfurter Rundschau. May 1, 2014, archived from the original on October 9, 2014 ; accessed on December 1, 2014 .
  6. ↑ Mercury in dental practices ( Memento from February 28, 2014 in the Internet Archive ) Research report of the professional association for health services and welfare (BGW) , Hamburg, 8/2012 (PDF 593 kB)
  7. ↑ seniorinnen.gruene.at ( Memento from August 27, 2010 in the Internet Archive )
  8. ↑ mercury.files.wordpress.com
  9. ↑ UN information on global occurrences and sources of emissions of mercury (English)
  10. ↑ https://www.dguv.de/medien/ifa/de/vera/2013_saet_gefahrstoffe/11_steinhausen.pdf
  11. ↑ Toxicity of mercury
  12. ↑ Compare the term mercaptan for "sulfur" alcohol.
  13. ↑ Federal Environment Agency Guideline values ​​for indoor air:, Federal Environment Agency, accessed on July 1, 2014.
  14. ^ Entry on mercury in the GESTIS substance database of the IFA , accessed on August 21, 2017 (JavaScript required)
  15. ↑ Mercury in energy-saving lamps and clinical thermometers. On the change in life expectancy after domestic mercury release , Free University of Berlin, accessed on July 1, 2014.
  16. ^ Ilka Kleffner et al .: An Enigmatic Case of Acute Mercury Poisoning: Clinical, Immunological Findings and Platelet Function. In: Frontiers in Neurology. September 28, 2017, accessed March 11, 2019 . doi.org/10.3389/fneur.2017.00517
  17. ↑ Jana Stegemann: Pausenbrot-Prozess: More toxic than warfare agents in the First World War. In: Süddeutsche Zeitung.de. March 7, 2019, accessed March 11, 2019 .
  18. ↑ Mercury in energy-saving lamps: Don't panic , test.de , December 3, 2010, accessed on July 1, 2014.
  19. ^ Environmental lexicon of the Institute for Applied Environmental Research in Cologne
  20. ↑ Indoor air pollution from energy-saving lamps: in the test only in individual cases , test.de , April 21, 2011, accessed on July 1, 2014.
  21. ↑ epa.gov
  22. ^ O. Wassermann, N. Weitz, C. Alsen-Hinrichs: Kieler Amalgam-Gutachten 1997. Medical, especially toxic findings in connection with a legal assessment of the manufacture and sale of amalgam as a material for dental fillings. Institute for Toxicology in the Clinic of the Christian Albrechts University in Kiel. ISBN 3-00-002089-6 , pp. 93-105. ( PDF )
  23. ↑ Dieter Melchart et al: Treatment of health complaints attributed to amalgam . In: Journal of Dental Research . April, 2008, p. 349-353 , PMID 18362317 .
  24. ^ Alois Scheucher, Anton Wald, Eduard Staudinger, Josef Scheipl, Ulrike Ebenhoch In: Zeitbilder 6, history and social studies, political education. 1st edition. Österreichischer Bundesverlag Schulbuch, Vienna 2004, p. 116.
  25. ↑ Max Daunderer: Poisons in everyday life. Where they appear. How they work. How to protect yourself against it . Verlag CH Beck, Munich 2005, p. 166f.
  26. ↑ See collection of sources on the history of German social policy 1867 to 1914 , Section II: From the Imperial Social Message to the February Decrees of Wilhelm II (1881–1890), Volume 3: Workers' Protection , edited by Wolfgang Ayaß , Darmstadt 1998, No. 18, No. 107, No. 170, No. 178 and No. 187.
  27. ↑ Ingrid Müller-Schneemayer: The Amalgam Controversy in the Twenties of the 20th Century. Dissertation . DNB 971084297 , p. 29 ff and p. 39, accessed on July 14, 2009.
  28. ^ S. Allan: Whitening skin can be deadly. In: Boston Globe. December 16, 2003, accessed July 8, 2009.
  29. ↑ 10 Facts About Minamata Disease , Retrieved July 6, 2007
  30. ↑ KA Björnberg, M. Vahter, K. Petersson-Grawé et al .: Methyl mercury and inorganic mercury in Swedish pregnant women and in cord blood: influence of fish consumption . In: Environ. Health Perspect. tape 111 , no. 4 , April 2003, p. 637-641 , PMID 12676628 , PMC 1241457 (free full text).
  31. ^ SA Lederman, RL Jones, KL Caldwell et al .: Relation between cord blood mercury levels and early child development in a World Trade Center cohort . In: Environ. Health Perspect. tape 116 , no. 8 , August 2008, p. 1085-1091 , doi : 10.1289 / ehp.10831 , PMID 18709170 , PMC 2516590 (free full text).
  32. ↑ LS Huang, GJ Myers, PW Davidson et al .: Is susceptibility to prenatal methylmercury exposure from fish consumption non-homogeneous? Tree-structured analysis for the Seychelles Child Development Study . In: Neurotoxicology . tape 28 , no. 6 , November 2007, pp. 1237–1244 , doi : 10.1016 / j.neuro.2007.08.009 , PMID 17942158 , PMC 2219920 (free full text).
  33. ^ G. Drasch, I. Schupp, H. Höfl, R. Reinke, G. Roider: Mercury burden of human fetal and infant tissues . In: Eur. J. Pediatr. tape 153 , no. 8 , August 1994, pp. 607-610 , PMID 7957411 .
  34. ↑ L. Palkovicova, M. Ursinyova, V. Masanova, Z. Yu, I. Hertz-Picciotto: Maternal amalgam dental fillings as the source of mercury exposure in developing fetus and newborn . In: J Expo Sci Environ Epidemiol . tape 18 , no. 3 , May 2008, p. 326-331 , doi : 10.1038 / sj.jes.7500606 , PMID 17851449 .
  35. ↑ CT Keim: The effects of chronic pre- and postnatal exposure to mercury on the strength of reactive astrogliosis in the medulla oblongata within the first 24 months of human life - a study on 76 corpses. Dissertation. Berlin 2000.
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  37. ↑ N. Ballatori, MW Lieberman, W. Wang: N-acetylcysteine ​​as an antidote in methylmercury poisoning . In: Environ. Health Perspect. tape 106 , no. 5 , May 1998, pp. 267-271 , PMID 9520359 , PMC 1533084 (free full text).
  38. ↑ D. Juresa, M. Blanusa, K. Kostial: Simultaneous administration of sodium selenite and mercuric chloride decreases efficacy of DMSA and DMPS in mercury elimination in rats. In: Toxicol Lett. 2005 Jan 15; 155 (1), pp. 97-102. PMID 15585364
  39. ↑ JC Hansen: Has selenium a beneficial role in human exposure to inorganic mercury? In: Med Hypotheses. 1988 Jan; 25 (1), pp. 45-53. PMID 3278198
  40. ↑ Tore Syversen, Parvinder Kaur: The toxicology of mercury and its compounds . In: Perspectives in Medicine (=  trace elements at a glance. Series of articles by the Society for Minerals and Trace Elements ). tape 2 , no. 1–4 , March 1, 2014, pp. 133–150 , doi : 10.1016 / j.permed.2013.09.006 ( sciencedirect.com [accessed April 27, 2017]).

Web links

Wiktionary: Mercury poisoning  - explanations of meanings, word origins, synonyms, translations