Heavy metal (chemical element)

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Samples of tungsten, a heavy metal. Shown are a 1 cm3 cube; and some rods with evaporated crystals; the foremost rod is prominently tarnished due to partial oxidation. The word tungsten comes from the Swedish tung sten, "heavy stone". With a density of 19.52 gm/cm3, tungsten is about 70% heavier than lead (density 11.34).

A heavy metal, broadly speaking, is any relatively dense metal.[1] More specific definitions have been proposed (sometimes including metalloids such as arsenic and antimony), but no definition has obtained widespread acceptance. Because of their heaviness and many specialized properties, heavy metals are useful in nearly all aspects of modern economic activity. Some are toxic, but a number are essential nutrients in trace amounts.

Definitions

Densities of metals and metalloids in the periodic table
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18
1  H He
2  Li Be B C N O F Ne
3  Na Mg Al Si P S Cl Ar
4  K Ca Sc Ti V Cr Mn Fe Co Ni Cu Zn Ga Ge As Se Br Kr
5  Rb Sr Y Zr Nb Mo Tc Ru Rh Pd Ag Cd In Sn Sb Te  I  Xe
6  Cs Ba 1 asterisk Lu Hf Ta W Re Os Ir Pt Au Hg Tl Pb Bi Po At Rn
7  Fr Ra † Lr Rf Db Sg Bh Hs Mt Ds Rg Cn 113 Fl 115 Lv 117 118
 
1 asterisk La Ce Pr Nd Pm Sm Eu Gd Tb Dy Ho Er Tm Yb
† Ac Th Pa U Np Pu Am Cm Bk Cf Es Fm Md No
 
   < 3.5 g/cm3
  
   7 to 9.99
   3.5 to 4.99
  
   > 10
   5 to 6.99
  

There is no widely agreed criteria-based definition of a heavy metal. Biochemist J. H. Duffus concluded in 2002 that so many different definitions had been used in the previous 60 years that it was an effectively meaningless term.[2]

Quantitative criteria used to define heavy metals have included density, atomic weight and atomic number.[2] Density criteria range from above 3.5 g/cm3 to above 7 g/cm3. Atomic weight definitions start at greater than sodium (22.98) to greater than 40,[n 1] or 200 or more.[4] Atomic numbers of heavy metals are generally given as greater than 20; sometimes this is capped at 92 (uranium). Density is the most commonly used of these criteria. Metalloids meeting the applicable criteria are often counted as heavy metals, particularly in environmental chemistry.[2]

Criteria based on chemical behaviour or periodic table position are known or have been used. The United States Pharmacopeia describes heavy metals as "metallic impurities that are colored [in aqueous solution] by sulfide ion."[5] Hawkes, writing in 1997, and in the context of fifty years of experience with the term, said it referred to, "metals with insoluble sulfides and hydroxides, whose salts produce colored solutions in water, and whose complexes are usually colored." He suggested referring to heavy metals as all of the metals in groups 3 to 16 that are in period 4 or greater, in other words, the transition metals and post-transition metals.[6][n 2][n 3]

Heavy metals are sometimes defined—on the basis of the Lewis acid (electronic pair acceptor) behaviour of their ions in aqueous solution—as class B and borderline metals.[7] In this scheme, class A metal ions prefer oxygen donors; class B ions prefer nitrogen or sulfur donors; and borderline or ambivalent ions show either class A or B characteristics, depending on the circumstances. Class A metals, which tend to have low electronegativity and form bonds with large ionic character, are the alkali and alkaline earths, aluminium, the group 3 metals, and the lanthanides and actinides. Class B metals, which tend to have higher electronegativity and form bonds with considerable covalent character, are mainly the heavier transition and post-transition metals. Borderline metals largely comprise the lighter transition and post-transition metals (plus arsenic and antimony). The distinction between the class A metals and the other two categories is sharp.[8][9] A frequently cited proposal[n 4] to use these classification categories instead of the more evocative[8] name heavy metal has not been widely adopted.[10]

Despite its questionable meaning, references to the term "heavy metal" appear regularly in scientific literature. A 2010 study found that it had been increasingly used and seemed to have become part of the language of science.[10] It is said to be an acceptable term, given its convenience and familiarity, as long as it is accompanied by a strict definition.[7]

Elements of atomic number 104 (rutherfordium) onwards are sometimes referred to as superheavy metals.[11] It remains to be seen if element 118, which is the heaviest element in the noble gas group, is in fact a metal. Predicted densities of elements 104–118 range from around 5 gm/cm3 for element 118, to 41 gm/cm3 for hassium (element 108);[12] the latter figure is 3.6 times that of lead (at 11.35 gm/cm3).

Etymology

The high densities of native metals such as copper, iron and gold may have been noticed in prehistory.[13] All other metals discovered from then until 1800 had fairly high densities. From 1809 onwards, light metals such as sodium, potassium and strontium were isolated. Their low densities challenged conventional wisdom and it was proposed to refer to them as metalloids (meaning "resembling in form or appearance").[14] This suggestion was not taken up and the new elements came to be recognised as metals.[15]

An early use of the term dates from 1817, when the German chemist Leopold Gmelin divided the elements into nonmetals, light metals and heavy metals.[16] Light metals had densities of 0.860–5.0 gm/cm3; heavy metals 5.308–22.000.[17]

Uses

Several lead bricks each the size of small pillows, stacked up like lego bricks to form a fort-like structure
A lead castle built to shield a radioactive sample in a lab

Heavy metals pervade nearly all aspects of modern economic activity.[18] They find general uses in, for example, metalworking and plating, electronics, batteries, catalysis, paint and pigments, jewellery, fertilisers, pesticides and herbicides.[19]

Some uses of heavy metals, including in sport and mechanical engineering, take advantage of their relatively high densities. In underwater diving, lead is used as a ballast; in handicap horse racing each horse must carry a specified lead weight, based on factors including past performance, so as to equalize the chances of competitors. In golf, tungsten, brass or copper inserts in fairway clubs and irons lower the centre of gravity of the club making it easier to get the ball into the air;[20] and golf balls with tungsten cores are claimed to have better flight characteristics.[21] In fly fishing, sinking fly lines have a PVC coating embedded with tungsten powder so as to achieve the required sink rate.[22] In track and field sport, steel balls used in the hammer throw and shot put events are filled with lead in order to attain the minimum weight required under international rules.[23] Tungsten was used in hammer throw balls at least up to 1980; the minimum size of the ball was increased in 1981 to eliminate the need for what was, at that time, an expensive metal (triple the cost of other hammers) not generally available in all countries.[24] Tungsten hammers were so dense that they penetrated too deeply into the turf.[25] In mechanical engineering, heavy metals are used for balance weights on wheels and crankshafts,[26] gyroscopes and propellers,[27] and centrifugal clutches;[28] or as ballast in boats,[29] aeroplanes,[30] and motor vehicles,[31] in situations requiring maximum weight in minimum space (for example in watch movements).[30]

Niche uses occur in electron microscopy and nuclear science. In electron microscopy, heavy metals such as lead, gold, palladium, platinum, or uranium are used to make conductive coatings and to introduce electron density into biological specimens by staining, negative staining or shadowing.[32] In nuclear science, heavy metals are used for radiation shielding and to focus radiation beams in linear accelerators and radiotherapy applications.[33]

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The higher the projectile density, the more effectively it can penetrate heavy armor plate…Os, Ir, Pt, and Re…are expensive…U offers an appealing combination of high density, reasonable cost, and high fracture toughness.

AM Russell and KL Lee
Structure-property relations
in nonferrous metals (2005, p. 16)

In military ordnance, tungsten or uranium is used in armour plating[34] and armour piercing projectiles; and in nuclear weapons to increase efficiency (by reflecting neutrons and momentarily delaying the expansion of reacting materials).[35] In the 1970s, tantalum was found to be more effective than copper in shaped charge and explosively formed anti-armour weapons on account of its higher density, allowing greater force concentration, and better deformability.[36] Less toxic heavy metals, such as copper, tin, tungsten and bismuth, and probably manganese (and boron, a metalloid), have replaced lead and antimony in the bullets used by some armies and in some recreational shooting munitions.[37] Doubts have been raised about the green credentials of tungsten.[38][39]

File:Laser glass slab.jpg
A slab of neodymium-doped laser glass

Other references or instances of heavy metals occur in soap chemistry; glass making, ceramics and pyrotechnics; medicine; numismatics; and with respect to children's toys and low-cost jewellery. In soap chemistry, heavy metals form insoluble soaps that are used in lubricating greases, paint dryers, and fungicides (apart from lithium, the alkali metals and the ammonium ion form soluble soaps).[40] The colours of glass, ceramic glazes and pyrotechnics are produced by the inclusion of heavy metals (or their compounds) such as iron, nickel, copper, chromium, manganese, cobalt, gold, silver or neodymium. The biocidal effects of some heavy metals have been known since antiquity.[41] Platinum, osmium, copper, ruthenium and other heavy metals, including arsenic, are used in anti-cancer treatments, or have shown potential.[42] Antimony (anti-protozoal), bismuth (anti-ulcer), gold (anti-arthritic), and iron (anti-malarial) are also important in medicine.[43] Copper, zinc, silver, gold or mercury are used in antiseptic formulations;[44] small amounts of selected heavy metals are used to control algal growth in, for example, cooling towers.[45] In numismatics, of two dozen elements that have been used in the world's monetised coinage only two, carbon and aluminium, are not heavy metals.[46][n 5] Children's toys and low-cost jewellery may be made, to a significant degree, of heavy metals such as chromium, nickel, cadmium or lead.[48]

Toxicity

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See also: Toxic heavy metal

Some heavy metals, especially chromium, arsenic, cadmium, mercury, lead and thallium are potentially hazardous due to their toxicity in combined or elemental forms. Hexavalent chromium, for example, is highly toxic as is mercury vapour and many mercury compounds.[49] These six elements have a strong affinity for sulfur; in the human body they usually bind, via sulfhydryl groups (–SH), to enzymes responsible for controlling the speed of metabolic reactions. The resulting sulfur-metal bonds inhibit the proper functioning of the enzymes involved; human health deteriorates, sometimes fatally.[50] Other heavy metals noted for their potential toxicity, particularly in an environmental science context, include nickel, copper, zinc, silver, tin, and antimony.[51][n 6] Health risks associated with some heavy metals have resulted in efforts to limit their indiscriminate use or to replace them with less toxic alternatives. For example, tetraethyl lead, (CH
3CH
2)
4Pb was added to petrol as an anti-knock agent, particularly during the 1930‒1970s,[53] but this practice has largely been phased out.[54]

Nutrition

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See also: Essential element

Trace amounts of some heavy metals are required for certain biological processes. These include vanadium and manganese (enzyme regulation or activation), iron and copper (oxygen and electron transport); cobalt (complex syntheses and cell metabolism), zinc (hydroxylation) and molybdenum (catalysis of redox reactions).[9][55] A deficiency of these essential elements may increase susceptibility to heavy metal poisoning; high doses can have adverse effects.[56]

Notes

  1. ↑ Excluding s- and f-block metals, hence starting with scandium[3]
  2. ↑ In this case aluminium is not regarded as a post-transition metal
  3. ↑ If Hawkes subsumed the lanthanides and actinides within group 3, his definition would encompass 55 heavy metals from scandium to uranium. Of these metals, those that do not usually form coloured complexes are: Sc and Y in group 3; La, Eu, Gd, Yb and Lu in the lanthanides; Ac, Th and Pa in the actinides; Ag in group 11; Zn and Cd in group 12; and the metals in groups 13—16. This translates to 63.6% or 35 of the heavy metals usually forming coloured complexes and 36.4% or 20 usually forming colourless complexes.
  4. ↑ Google recorded 945 citations for the paper in question,[8] as at 19 April 2016.
  5. ↑ Weller[47] classifies coinage metals as precious metals (e.g. silver, gold, platinum); heavy metals of very high durability (nickel); heavy metals of low durability (copper, iron, zinc, tin and lead); and light metals (aluminium).
  6. ↑ Tungsten may be another such toxic heavy metal.[52]

Sources

Citations

  1. ↑ Qian 2009, p. 496
  2. ↑ 2.0 2.1 2.2 Duffus 2002
  3. ↑ Rand, Wells & McCarty 1995, p. 23
  4. ↑ Baldwin & Marshall 1999, p. 267: "The term 'heavy metal'…should probably be reserved for those elements with an atomic mass of 200 or greater" i.e. mercury onwards.
  5. ↑ The United States Pharmacopeia 1985, p. 1189
  6. ↑ Hawkes 1997
  7. ↑ 7.0 7.1 Rainbow 1991, p. 416
  8. ↑ 8.0 8.1 8.2 Nieboer & Richardson 1980
  9. ↑ 9.0 9.1 Nieboer & Richardson 1978
  10. ↑ 10.0 10.1 Hübner, Astin & Herbert 2010
  11. ↑ Loveland 2014
  12. ↑ Hoffman, Lee & Pershina 2011, pp. 1691,1723; Bonchev & Kamenska 1981, p. 1182
  13. ↑ Raymond 1984, p. 9
  14. ↑ Oxford English Dictionary 1989; Gordh, Gordh & Headrick 2003, p. 753
  15. ↑ Goldsmith 1982, p. 526
  16. ↑ Habashi 2009, p. 31
  17. ↑ Gmelin 1849, p. 2
  18. ↑ Provenzano 1975, p. 339
  19. ↑ Landis, Sofield & Yu 2011, p. 269
  20. ↑ Jackson & Summitt 2006, pp. 10, 13
  21. ↑ Shedd 2002, p. 80.5; Kantra 2001, p. 10
  22. ↑ Spolek 2007, p. 239
  23. ↑ White 2010, p. 139
  24. ↑ Dapena & Teves 1982, p. 78
  25. ↑ Burkett 2010, p. 80
  26. ↑ VanGelder 2014, pp. 354, 801
  27. ↑ National Materials Advisory Board 1971, pp. 35–37
  28. ↑ Frick 2000, p. 342
  29. ↑ Moore & Ramamoorthy 1984, p. 102
  30. ↑ 30.0 30.1 National Materials Advisory Board 1973, p. 58
  31. ↑ Livesey 2012, p. 57
  32. ↑ Chandler & Roberson 2009, p. 47; Ismail, Khulbe & Matsuura 2015, pp. 302, 367, 373
  33. ↑ Scoullos et al. 2001, p. 315; Ariel, Barta & Brandon 1973, p. 126
  34. ↑ Rockhoff 2012, p. 314
  35. ↑ Morstein 2005, p. 129
  36. ↑ Russell & Lee 2005, pp. 218–219
  37. ↑ Lach et al. 2015; DiMaio 2016, p. 154
  38. ↑ Preschel 2005
  39. ↑ Guandalini et al. 2011
  40. ↑ Elliot 1946, p. 11; Warth 1956, p. 571
  41. ↑ Weber & Rutula 2001, p. 415
  42. ↑ Dunn 2009; Bonetti et al. 2009
  43. ↑ Desoize 2004
  44. ↑ Atlas 1986, p. 359; Lima et al. 2013
  45. ↑ Volesky 1990, p. 174
  46. ↑ Roe & Roe 1992
  47. ↑ Weller 1976, p. 4
  48. ↑ Guney & Zagury 2012; Cui et al. 2015
  49. ↑ Kozin & Hansen 2013, p. 80
  50. ↑ Baird & Cann 2012, pp. 519–520; 567; Rusyniak et al. 2010, p. 387
  51. ↑ Baird & Cann 2012, pp. 558; United States Government 2014
  52. ↑ United States Environmental Protection Agency 2014
  53. ↑ Lovei 1998, p. 15
  54. ↑ Mason 2015, p. 130
  55. ↑ Bánfalvi 2011, p. 12; Emsley 2011, pp. 138, 310, 331, 604
  56. ↑ Venugopal & Luckey 1978, p. 307

References

  • Ariel E, Barta J & Brandon D 1973, "Preparation and properties of heavy metals", Powder Metallurgy International, vol. 5, no. 3, pp. 126–129
  • Atlas RM 1986, Basic and practical microbiology, Macmillan Publishing Company, New York, ISBN 0-02-304350-4
  • Baird C & Cann M 2012, Environmental chemistry, 5th ed., W. H. Freeman and Company, New York, ISBN 1-4292-7704-1
  • Baldwin DR & Marshall WJ 1999, 'Heavy metal poisoning and its laboratory investigation', Annals of Clinical Biochemistry, vol. 36, no. 3, pp. 267–300, doi:10.1177/000456329903600301
  • Bánfalvi G 2011, 'Heavy metals, trace elements and their cellular effects', in G Bánfalvi (ed.), Cellular effects of heavy metals, Springer, Dordrecht, pp.  3–28, ISBN 978-94-007-04275
  • Bonchev D & Kamenska V 1981, 'Predicting the properties of the 113–120 transactinide elements', The Journal of Physical Chemistry, vo. 85, no. 9, pp. 1177–86, doi:10.1021/j150609a021
  • Bonetti A, Leone R, Muggia F & Howell SB (eds) 2009, Platinum and other heavy metal compounds in cancer chemotherapy: Molecular mechanisms and clinical applications, Humana Press, New York, ISBN 978-1-60327-458-6
  • Burkett B 2010, Sport mechanics for coaches, 3rd ed., Human Kinetics, Champaign, Illinois, ISBN 0-7360-8359-6
  • Chandler DE & Roberson RW 2009, Bioimaging: Current concepts in light & electron microscopy, Jones & Bartlett Publishers, Boston, ISBN 978-0-7637-3874-7
  • Chowdhury BA & Chandra RK 1987, 'Biological and health implications of toxic heavy metal and essential trace element interactions', Progress in Food & Nutrition Science, vol. 11, no. 1, pp. 55–113, doi:10.1002/food.19760200720
  • CHB 1881, "Actinium, A new metal", Journal of the Chemical Society, Abstracts, vol. 40, doi:10.1039/CA8814001097
  • Cotton S 2006,Lanthanide and actinide chemistry, reprinted with corrections 2007, John Wiley & Sons, Chichester, ISBN 978-0-470-01005-1
  • Cui X-Y, Li S-W, Zhang S-J, Fan Y-Y, Ma LQ 2015, "Toxic metals in children's toys and jewelry: Coupling bioaccessibility with risk assessment", Environmental Pollution, vol. 200, pp. 77–84, doi:10.1016/j.envpol.2015.01.035
  • Dapena J & Teves MA 1982, 'Influence of the diameter of the hammer head on the distance of a hammer throw', Research Quarterly for Exercise and Sport, vol. 53, no. 1, pp. 78–81, doi:10.1080/02701367.1982.10605229
  • Desoize B 2004, "Metals and metal compounds in cancer treatment", Anticancer Research, vol. 24, no. 3a, pp. 1529–1544, Lua error in package.lua at line 80: module 'strict' not found.
  • DiMaio VJM 2016, Gunshot wounds: Practical aspects of firearms, ballistics, and forensic techniques, 3rd ed., CRC Press, Boca Raton, Florida, ISBN 978-1-4987-2570-5
  • Duffus JH 2002, ' "Heavy metals"—A meaningless term?', Pure and Applied Chemistry, vol. 74, no. 5, pp. 793–807, doi:10.1351/pac200274050793
  • Dunn P 2009, Unusual metals could forge new cancer drugs, University of Warwick, accessed 23 March 2016
  • Elliott SB 1946, The alkaline-earth and heavy-metal soaps, Reinhold Publishing Corporation, New York
  • Emsley J 2011, Nature's building blocks, new edition, Oxford University Press, Oxford, ISBN 978-0-19-960563-7
  • Frick JP (ed.) 2000, Woldman's engineering alloys, 9th ed., ASM International, Materials Park, Ohio, ISBN 0-87170-691-1
  • Gmelin L 1849, Hand-book of chemistry, vol. III, Metals, translated from the German by H Watts, Cavendish Society, London
  • Goldsmith RH 1982, 'Metalloids', Journal of Chemical Education, vol. 59, no. 6, pp. 526–527, doi:10.1021/ed059p526
  • Gordh G, Gordh G & Headrick D 2003, A dictionary of entomology, CABI Publishing, Wallingford, ISBN 0-85199-655-8
  • Guandalini GS, Zhang L, Fornero E, Centeno JA, Mokashi VP, Ortiz PA, Stockelman MD, Osterburg AR & Chapman GG 2011, 'Tissue distribution of tungsten in mice following oral exposure to sodium tungstate,' Chemical Research in Toxicology, vol. 24, no. 4, pp 488–493, doi:10.1021/tx200011k
  • Guney M & Zagury GJ 2012, "Heavy metals in toys and low-cost jewelry: Critical review of U.S. and Canadian legislations and recommendations for testing", Environmental Science & Technology, vol. 48, pp. 1238–1246, doi:10.1021/es4036122
  • Habashi F 2009, 'Gmelin and his Handbuch', Bulletin for the History of Chemistry, vol. 34, no. 1, pp. 30–1
  • Hawkes SJ 1997, 'What is a "heavy metal"?', Journal of Chemical Education, vol. 74, no. 11, p. 1374, doi:10.1021/ed074p1374
  • Hoffman DC, Lee DM & Pershina V 2011, 'Transactinide elements and future elements,' in LR Morss, N Edelstein, J Fuger & JJ Katz (eds), The chemistry of the actinide and transactinide elements, 4th ed., vol. 3, Springer, Dordrecht, pp. 1652-1752, ISBN 978-94-007-0210-3
  • Hübner R, Astin KB & Herbert RJH 2010, 'Heavy metal'—time to move on from semantics to pragmatics?', Journal of Environmental Monitoring, vol. 12, pp. 1511–1514, doi:10.1039/C0EM00056F
  • Ismail AF, Khulbe K & Matsuura T 2015, Gas separation membranes: Polymeric and inorganic, Springer, Cham, Switzerland, ISBN 978-3-319-01095-3
  • Jackson J & Summitt J 2006, The modern guide to golf clubmaking: The principles and techniques of component golf club assembly and alteration, 5th ed., Hireko Trading Company, City of Industry, California, ISBN 9780961941307
  • Kantra S 2001, 'What's new', Popular Science, vol. 254, no. 4, April, p. 10
  • Kozin LF & Hansen SC 2013, Mercury handbook: Chemistry, applications and environmental impact, RSC Publishing, Cambridge, ISBN 978-1-84973-409-7
  • Lach K, Steer B, Gorbunov B, Mička V & Muir RB 2015, 'Evaluation of exposure to airborne heavy metals at gun shooting ranges', The Annals of Occupational Hygiene, vol. 59, no. 3, pp. 307–323, doi:10.1093/annhyg/meu097
  • Landis W, Sofield R & Yu M-H 2010, Introduction to environmental toxicology: Molecular substructures to ecological landscapes, 4th ed., CRC Press, Boca Raton, Florida, ISBN 978-1-4398-0411-7
  • Lima E, Guerra R, Lara V & Guzmán A 2013, "Gold nanoparticles as efficient antimicrobial agents for Escherichia coli and Salmonella typhi" Chemistry Central, vol. 7:11, doi:10.1186/1752-153X-7-11
  • Livesey A 2012, Advanced motorsport engineering, Routledge, London, ISBN 978-0-75-068908-3
  • Lovei M 1998, Phasing out lead from gasoline: Worldwide experience and policy implications, World Bank Technical Paper no. 397, The World Bank, Washington DC, ISSN 0253-7494
  • Loveland W 2014, 'Superheavy carbonyls', Science, vol. 346, no. 6203, pp. 1451–1452, doi:10.1126/science.1259349
  • Mason RP 2015, "Mercury and Lead", in RE Hester & RM Harrison RM (eds), Still only one Earth: Progress in the 40 years since the first UN conference on the environment, Royal Society of Chemistry, Cambridge, pp. 107–149, ISBN 978-1-78262-076-1
  • Moore JW & Ramamoorthy S 1984, Heavy metals in natural waters: Applied monitoring and impact assessment, Springer Verlag, New York, ISBN 978-1-4612-9739-0
  • Morstein JH 2005, 'Fat Man', in EA Croddy & YY Wirtz (eds), Weapons of mass destruction: An encyclopedia of worldwide policy, technology, and history, ABC-CLIO, Santa Barbara, California, ISBN 1-85109-495-4
  • National Materials Advisory Board 1971, Trends in the use of depleted uranium, National Academy of Sciences – National Academy of Engineering, Washington DC
  • National Materials Advisory Board 1973, Trends in usage of tungsten, National Academy of Sciences – National Academy of Engineering, Washington DC
  • National Organization for Rare Disorders 2015, Heavy metal poisoning, accessed 3 March 2016
  • Nieboer E & Richardson D 1978, "Lichens and 'heavy metals' ", International Lichenology Newsletter, vol. 11, no. 1, pp. 1–3
  • Nieboer E & Richardson DHS 1980, "The replacement of the nondescript term ‘heavy metals’ by a biologically and chemically significant classification of metal ions", Environmental Pollution Series B, Chemical and Physical, vol. 1, no. 1, pp. 3–26, doi:10.1016/0143-148X(80)90017-8
  • Oxford English Dictionary 1989, 2nd ed., Oxford University, Oxford, ISBN 0-19-861213-3
  • Preschel J 2005, 'Green bullets not so eco-friendly', CBS News, July 29, accessed 18 March 2016
  • Provenzano G 1975, 'Risk-benefit analysis and the economics of heavy metals control', in PA Krenkel (ed.), Heavy metals in the aquatic environment: An international conference, Pergamon Press, Oxford, pp. 339–346, ISBN 0-08-018068-X
  • Qian Y 2009, 'Heavy metal-regulated gene expression', in K Ramos (ed.), Comprehensive toxicology, vol. 2, Cellular and Molecular Toxicology, Elsevier, Amsterdam, pp. 495–522, ISBN 978-0-08-046868-6
  • Rainbow PS 1991, "The biology of heavy metals in the sea", in J Rose (ed.), Water and the environment, Gordon and Breach Science Publishers, Philadelphia, pp. 415‒432, ISBN 2-88124-747-4
  • Rand GM, Wells PG & McCarty LS 1995, 'Introduction to aquatic toxicology', in GM Rand (ed.), Fundamentals of aquatic toxicology: Effects, environmental fate and risk assessment, 2nd ed., Taylor & Francis, London, pp. 3–70, ISBN 1-56032-090-7
  • Raymond R 1984, Out of the fiery furnace: The impact of metals on the history of mankind, MacMillan, South Melbourne, ISBN 0-333-38024X
  • Remy H 1956, Treatise on inorganic chemistry, vol. 2, Elsevier Publishing Company, Amsterdam
  • Rockhoff H 2012, America's economic way of war: War and the US economy from the Spanish–American War to the Persian Gulf War, Cambridge University Press, Cambridge, ISBN 978-0-521-85940-0
  • Roe J & Roe M 1992, 'World's coinage uses 24 chemical elements', World Coinage News, vol. 19, no. 4, pp. 24–24; no. 5, pp. 18–19
  • Russell AM & Lee KL 2005, Structure–property relations in nonferrous metals, John Wiley & Sons, Hoboken, New Jersey, ISBN 0-471-64952-X
  • Rusyniak DE, Arroyo A, Acciani J, Froberg B, Kao L & Furbee B 2010, "Heavy metal poisoning: Management of intoxication and antidotes", in A Luch (ed.), Molecular, clinical and environmental toxicology, vol. 2, Birkhäuser Verlag, Basel, pp. 365–396, ISBN 978-3-7643-8337-4
  • Schweitzer GK & Pesterfield LL 2010, The aqueous chemistry of the elements, Oxford University Press, Oxford, ISBN 978-0-19-539335-4
  • Scoullos M (ed.), Vonkeman GH, Thornton I & Makuch Z 2001, Mercury — Cadmium — Lead handbook for sustainable heavy metals policy and regulation, Kluwer Academic Publishers, Dordrecht, ISBN 1-4020-0224-6
  • Shedd KB 2002, 'Tungsten', Minerals yearbook, United States Geological Survey
  • Spolek G 2007, 'Design and materials in fly fishing', in A Subic (ed.), Materials in sports equipment, Volume 2, Woodhead Publishing, Abington, Cambridge, pp. 225–247, ISBN 978-1-84569-131-8
  • The United States Pharmacopeia 1985, 21st Revision, The United States Pharmacopeial Convention, Rockville, Maryland, ISBN 0-913595-04-7
  • Topp NE 1065, The chemistry of the rare-earth elements, Elsevier Publishing Company, Amsterdam
  • United States Environmental Protection Agency 2014, Technical Fact Sheet–Tungsten, accessed 27 March 2016
  • United States Government 2014, Toxic Pollutant List, Code of Federal Regulations, 40 CFR 401.15., accessed 27 March 2016
  • VanGelder KT 2014, Fundamentals of automotive technology: Principles and practice, Jones & Bartlett Learning, Burlington MA, ISBN 978-1-4496-7108-2
  • Venugopal B & Luckey TD 1978, Metal toxicity in mammals, vol. 2, Plenum Press, New York, ISBN 978-0-306-37177-6
  • Volesky B 1990, Biosorption of heavy metals, CRC Press, Boca Raton, ISBN 0-8493-4917-6
  • Warth AH 1956, The chemistry and technology of waxes, Reinhold Publishing Corporation, New York
  • Weber DJ & Rutula WA 2001, "Use of metals as microbicides in preventing infections in healthcare", in Disinfection, sterilization, and preservation, 5th ed., SS Block (ed.), Lippincott, Williams & Wilkins, Philadelphia, ISBN 0-683-30740-1
  • Weller G 1976, Cleaning and preservation of coins and medals, S J Durst, New York, ISBN 0-915262-03-7
  • White C 2010, Projectile dynamics in sport: Principles and applications, Routledge, London, ISBN 978-0-415-47331-6
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