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| 融点 | 231.9 °C (lit.) | | 沸点 | 2270 °C (lit.) | | 比重(密度) | 7.310 g/mL at 25 °C (lit.) | | 蒸気圧 | 1Pa at 1223.85℃ | | 闪点 | 2270°C | | 貯蔵温度 | no restrictions. | | 溶解性 | H2O: soluble | | 外見 | wire | | 色 | Silvery-gray | | 比重 | 7.31 | | 電気抵抗率 (resistivity) | 11 μΩ-cm, 20°C | | 水溶解度 | reacts slowly with cold dilute HCl, dilute HNO3, hot dilute H2SO4; readily with conc HCl, aqua regia [MER06] | | Crystal Structure | Cubic, Alpha-Tin; Diamond Structure - Space Group Fd3m | | Merck | 13,9523 | | 暴露限界値 | ACGIH: Ceiling 2 ppm
OSHA: Ceiling 5 ppm(7 mg/m3)
NIOSH: IDLH 50 ppm; Ceiling 5 ppm(7 mg/m3) | | 安定性： | Stable. Incompatible with strong oxidizing agents. Highly flammable as a powder. Can, in powder form, lead to dust explosions. Moisture sensitive. | | InChIKey | OLGIDLDDXHSYFE-UHFFFAOYSA-N | | CAS データベース | 7440-31-5(CAS DataBase Reference) | | EPAの化学物質情報 | Tin (7440-31-5) |
| 外観 | 銀白色の粒状 | | 歴史 | スズはもっとも古くから知られた金属の一つで、紀元前数千年のころから地中海沿岸諸国、ペルシア、インド、中国などで広く知られていた。また少なくとも銅との合金の青銅として石器時代に続く時代に使用され、いわゆる青銅器時代を画している。ペルーのインカ遺跡からは銅に加えるための純粋なスズがみいだされている。スズという名称の起源は明らかでないが、中国では周代の紀元前1000年ごろ、すでに錫(すず)という文字が使われ、スズ冶金(やきん)、青銅などが詳しく記されている。日本では古代の青銅器製品はほとんどが中国、朝鮮からの輸入品であったし、スズそのものが知られていたわけではない。しかしスズそのものについては、8世紀ごろの記載があり、白 (しろめ)、白鑞(しろめ)、白﨟(ろう)などとよんでいた。宇田川榕菴(うだがわようあん)の『舎密開宗(せいみかいそう)』（1837）には「斯丹紐母（スタンニユム）、錫」と記されている。ラテン語のstannumの名称は初めはスズを意味したものではなく、銀と鉛との合金に対して用いられたが、4世紀になってスズをさすようになった。元素記号はこの語からきている。 | | 製法 | 天然に錫石SnO2として産する。鉱石を炭素、珪石(けいせき)、石灰石などを加えて電気炉内で溶錬して金属とする。不純物の鉄が含まれるので、さらに還元剤などを加えて電気炉で溶錬を繰り返して粗スズを得る。これを乾式法または電解法で精錬する。このほかにブリキスズから回収される。ブリキスズを陽極として水酸化ナトリウム溶液中で電解する方法や、加圧した塩素ガスによってスズのみを塩化物とする塩素法などがある。 2011年の世界のスズの鉱石生産量は約30万1000トンで、主要国は中国（約42.2％）、インドネシア（約25.9％）、ペルー（約9.6％）である。また電気スズの生産量は約36万7000トンで、アジア（約82.6％）、北南米（約14.2％）、ヨーロッパ（約3.0％）、消費量は約38万3000トンで、アジア（約69.7％）、ヨーロッパ（約17.8％）北南米（約12.3％）となっている（WBMS：世界金属統計局）。［守永健一・中原勝儼］ | | 定義 | 本品は、元素 Sn である。 | | 性質 | α(アルファ)-スズ、β(ベータ)-スズの2変態があり、低温で安定なのはα型で、18℃以上でβ型が安定になる。普通白色で、金属光沢があるのがβ-スズで、白色スズともよばれる。これを零下30℃以下に長時間保つとα-スズ（灰色スズという）になる。このとき金属状スズは表面に突起を生じ、ついには粉状に壊れてしまう。この現象は19世紀にロシアの博物館のスズ製品でみつけられ、スズペストとよばれた。通常は銀白色の金属で展性、延性に富み、箔(はく)や線に加工することができる。金属スズを曲げるときパチパチと音を発するが、これはティンクライTin Cry（錫鳴り）といわれている。 スズは空気中で安定であるが、熱すると燃えて酸化スズ(Ⅳ)となる。ハロゲンとは激しく反応して四ハロゲン化物を生じる。酸には水素を発して溶け、スズ(Ⅱ)塩となるが、濃硝酸ではスズ酸（酸化スズ(Ⅳ)の水和物）SnO2・nH2Oをつくる。水酸化アルカリ溶液に溶けて亜スズ酸塩をつくる。［守永健一・中原勝儼］ | | 用途 | スズは無害で耐食性に優れ、空気中で変色せず、外観が美しいので、鉄、鉄鋼、銅などの表面にめっきする。とくに鉄板の表面にめっきしたものをブリキという。スズめっきの対象は食器、美術工芸品から電子部品まで広い範囲にわたる。また、はんだ、青銅、減摩合金、易融合金など合金としての用途が広い。酸化物は窯業用顔料、うわぐすり（釉）、研摩剤などに、有機スズ化合物はポリ塩化ビニルの安定剤、農業用殺菌剤、重合触媒などに用いられる。 | | 溶解性 | 王水に溶け、硝酸によってメタすず酸に変わる。 | | 解説 | Sn．原子番号50の元素．電子配置[Kr]4d105s25p2の周期表14族金属元素．原子量118.710(7)．天然には質量数112～124の10種の安定同位体があり，おもなものは116(14.54(9)％)，118(24.22(9)％)，120(32.58(9)％)．ほかに99～137の放射性同位体がある．安定同位体数のもっとも多い元素である．スズとその合金は先史時代から用いられていた金属で，元素記号Snはラテン語名stannumに由来する．本来銀と鉛の合金を意味していたが，のちにスズをさすようになった．天然にはおもにスズ石SnO2，黄錫鉱Cu2FeSnS4として産出する．地殻中の存在度2.5 ppm．可採埋蔵量6100百万t(Sn含有量)の順位は，中国28％，マレーシア16％，インドネシア13％，ペルー12％，以下ブラジル，ボリビアである．スズ石をばい焼して，As，Sなどの不純物を除き，コークス，石灰石を加えて，高炉または反射炉で加熱還元し粗スズとする．粗スズをさらに反射炉による溶錬または電解精錬によって精製する．αスズ(灰色スズ，低温相，立方晶系)とβスズ(白色スズ，高温相，正方晶系)の2変態があり，転移温度は13.2 ℃．融解物からはβスズが結晶する．白色金属光沢のある展延性に富む金属で，密度5.75 g cm－3(20 ℃，α)，7.31 g cm－3(20 ℃，β)．融点231.97 ℃，沸点2270 ℃．融解熱7.194 kJ mol－1，蒸発熱290.4 kJ mol－1．第一イオン化エネルギー7.344 eV．スズの酸化数は2，4で，SnⅡは不安定で強い還元性を示す．標準電極電位(Sn2＋/Sn)－0.1375 V，(Sn4＋/Sn2＋)＋0.15 V．濃塩酸には水素を発生しながら溶けてSnⅡ Cl2に，濃硝酸では不溶性のSnO2･nH2Oになる．強アルカリと煮沸するとスズ酸塩MⅠ2[SnⅣ (OH)6]をつくって溶ける．スズは常温の空気中で安定であるが，加熱するとSnⅣ O2を生じる．フッ素以外のハロゲンXとはげしく反応して，SnⅣ X4を生じる．室温ではフッ素に対して安定であるが，高温ではSnF2，SnF4をつくる．[SnIⅡCl3]－，[SnIⅡCl4]2－，[SnIⅡBr3]－ のようなハロゲノ錯イオンや，[Sn(C2O4)2]2－，[SnⅣ(OH)6]2－ なども知られている．スズは水素よりイオン化傾向が大きく，Ag，Hg，Bi，Cu，Pt，Auなどのイオンを金属まで還元することができる．また，多くの有機スズ化合物が知られている．用途は，スズめっき([別用語参照]ブリキ)，缶用スズめっき鋼板，スズはくの製造のほか，多くの金属と合金をつくりやすいことから青銅，はんだ，軸受合金，活字合金などの原料として広く使われている．酸化スズインジウム(ITO)はフラットパネルディスプレイ用透明電極として需要が増加している．リン青銅(Cu-Sn-P)は電子部品リードフレームに使われる．有機スズ化合物はプラスチック安定剤，防かび剤などに使用される．わが国の最大の用途は，スズを主成分とするはんだ用で約30％，ついで有機スズ化合物など化成品15％ 強，スズめっき缶・鋼板用約15％ 弱，電子部品用10％ 弱で，透明電極用の使用量は1～2％ とされる．消費量約35000 t のほぼ全量をインドネシア，中国，マレーシアからの輸入と鉱さい，煙灰などからのリサイクル(～750 t)でまかなった(2005年) 森北出版「化学辞典（第2版） | | 用途 | 標準液調製原料、試薬(還元剤)。 | | 用途 | 還元剤。有機合成(和光試薬時報Vol.64 No.2,p.26(1996))。 | | 用途 | 合金材料、試薬(還元剤)、すず化合物の製造原料。 | | 化粧品の成分用途 | 表面改質剤 | | 説明 | Tin has a long, colorful history. The extraction and use of tin
began during the Bronze Age around 3000 BC when early
craftsmen discovered that bronze – a noncorrosive metal that is
extremely hard and strong enough to be used for spears,
swords, arrows, and other especially important objects at that
time – could be produced by smelting tin with copper. Tin is
also the primary constituent of pewter. Long ago, people
developed the belief that trace amounts of tin seemed to help
prevent fatigue and depression, and that drinking out of tin
cups could help combat these ailments. Tin toys, tin coated
cans, and tin roofs have also enjoyed great popularity in
the past. | | 化学的特性 | Tin is a gray to almost silver-white, ductile, malleable, lustrous metal. | | 物理的性質 | Tin is a soft, silvery-white metal located in the carbon group, similar in appearance to freshcutaluminum. When polished, it takes on a bluish tint caused by a thin protective coatingof oxidized tin. This property makes it useful as a coating for other metals. It is malleable andductile, meaning it can be pounded, rolled, and formed into many shapes, as well as “pulled”into wires through a die.
There are two allotropes of tin. One is known as gray or alpha (α) tin, which is not verystable. The other is known as white tin or beta (β), which is the most common allotrope. Thetwo forms (allotropes) of tin are dependent on temperature and crystalline structure. Whitetin is stable at about 13.2°C. Below this temperature, it turns into the unstable gray alphaform. There is also a lesser-known third allotrope of tin called “brittle tin,” which exists above161°C. Its name is derived from its main property.
Tin’s melting point is 231.93°C, its boiling point is 2,602°C, and the density is 5.75 g/cm3for the gray allotrope (alpha) and 7.287 g/cm3 for the white allotrope (beta). | | 同位体 | There are 49 isotopes of tin, 10 of which are stable and range from Sn-112to Sn-124. Taken together, all 10 stable isotopes make up the natural abundance of tinfound on Earth. The remaining 39 isotopes are radioactive and are produced artificially innuclear reactors. Their half-lives range from 190 milliseconds to 1×10+5 years. | | 名前の由来 | The name “tin” is thought to be related to the pre-Roman Etruscan god
Tinia, and the chemical symbol (Sn) comes from stannum, the Latin word for tin. | | 天然物の起源 | Tin is the 49th most abundant element found in the Earth’s crust. Although tin is nota rare element, it accounts for about 0.001% of the Earth’s crust. It is found in deposits inMalaysia, Thailand, Indonesia, Bolivia, Congo, Nigeria, and China. Today, most tin is minedas the mineral ore cassiterite (SnO2), also known as tinstone, in Malaysia. Cassiterite is tin’smain ore. There are no significant deposits found in the United States, but small deposits arefound on the southeast coast of England. To extract tin from cassiterite, the ore is “roasted” ina furnace in the presence of carbon, thereby reducing the metal from the slag. | | 特性 | Although tin is located in group 14 as a metalloid, it retains one of the main characteristicsof metals: in reacting with other elements, it gives up electrons, forming positive ions just asdo all metals.
Tin has a relatively low melting point (about 231°C or 4,715°F), and it reacts with someacids and strong alkalis, but not with hot water. Its resistance to corrosion is the main characteristicthat makes it a useful metal.
There is an interesting historical event related to the two main allotropes of tin. At temperaturesbelow 13 degrees centigrade, “white” tin is slowly transformed into “gray” tin, whichis unstable at low temperatures, and during the brutally cold winter of 1850 in Russia, thetin buttons sewn on soldiers’ uniforms crumbled as the tin changed forms. In the 1800s, tinwas also widely used for pots, pans, drinking cups, and dinner flatware. However, at very lowtemperatures, these implements also disintegrated as their chemical structure was altered. | | 来歴 | Known to the ancients. Tin is found chiefly
in cassiterite (SnO2). Most of the world’s supply comes from
China, Indonesia, Peru, Brazil, and Bolivia. The U.S. produces
almost none, although occurrences have been found in Alaska
and Colorado. Tin is obtained by reducing the ore with coal
in a reverberatory furnace. Ordinary tin is composed of ten
stable isotopes; thirty-six unstable isotopes and isomers are
also known. Ordinary tin is a silver-white metal, is malleable,
somewhat ductile, and has a highly crystalline structure. Due
to the breaking of these crystals, a “tin cry” is heard when a
bar is bent. The element has two allotropic forms at normal
pressure. On warming, gray, or α tin, with a cubic structure,
changes at 13.2°C into white, or β tin, the ordinary form of the
metal. White tin has a tetragonal structure. When tin is cooled
below 13.2°C, it changes slowly from white to gray. This change
is affected by impurities such as aluminum and zinc, and can
be prevented by small additions of antimony or bismuth. This
change from the α to β form is called the tin pest. Tin–lead
alloys are used to make organ pipes. There are few if any uses for gray tin. Tin takes a high polish and is used to coat other
metals to prevent corrosion or other chemical action. Such
tin plate over steel is used in the so-called tin can for preserving
food. Alloys of tin are very important. Soft solder, type
metal, fusible metal, pewter, bronze, bell metal, Babbitt metal,
white metal, die casting alloy, and phosphor bronze are some
of the important alloys using tin. Tin resists distilled sea and
soft tap water, but is attacked by strong acids, alkalis, and acid
salts. Oxygen in solution accelerates the attack. When heated
in air, tin forms SnO2, which is feebly acid, forming stannate
salts with basic oxides. The most important salt is the chloride
(SnCl2 · H2O), which is used as a reducing agent and as a mordant
in calico printing. Tin salts sprayed onto glass are used
to produce electrically conductive coatings. These have been
used for panel lighting and for frost-free windshields. Most
window glass is now made by floating molten glass on molten
tin (float glass) to produce a flat surface (Pilkington process).
Of recent interest is a crystalline tin–niobium alloy that is superconductive
at very low temperatures. This promises to be
important in the construction of superconductive magnets
that generate enormous field strengths but use practically no
power. Such magnets, made of tin–niobium wire, weigh but
a few pounds and produce magnetic fields that, when started
with a small battery, are comparable to that of a 100 ton electromagnet
operated continuously with a large power supply.
The small amount of tin found in canned foods is quite harmless.
The agreed limit of tin content in U.S. foods is 300 mg/kg.
The trialkyl and triaryl tin compounds are used as biocides
and must be handled carefully. Over the past 25 years the
price of commercial tin has varied from 50￠/lb ($1.10/kg) to
about $6/kg. Tin (99.99% pure) costs about $260/kg. | | 使用 | Tin is used in tin plating; soldering; dental alloys; collapsible tubes; in the production of tin salts. | | 使用 | One of the most important uses of tin is in the coating of thin steel sheets to make “tinplate,” which in turn is used to make what is known as the “tin can.” The tin coating is thin,inexpensive to apply, and resistant to most foods for extended periods of time. Other inertcoatings are sometimes used on the inside of the can to further protect the foods for longerperiods of time.
Tin is alloyed with many metals. It is added to lead to make low-melting alloys for firepreventionsprinkler systems and easy-melting solder.
It is used for bearings, to plate electrodes, and to make pewter, Babbitt metal, and dentalamalgams.
Tin also has been mixed with other metals for making castings for letter type used in printingpresses.
Some compounds of tin are used as fungicides and insecticides. Tin is also used for “weighting”silk, to give the fabric more body and heft.
Molten glass is poured over a pool of molten tin to produce smooth, solid, flat plate andwindow glass. | | 使用 | Chiefly for tin-plating and manufacture of food, beverage and aerosol containers, soldering alloys, babbitt and type metals, manufacture of tin salts, collapsible tubes, coating for copper wire. Principle component in pewter. Alloys as dental materials (silver-tin-mercury), nuclear reactor components (tin-zirconium), aircraft components (tin-titanium), bronze (copper-tin), brass. | | 定義 | A white lustrous metal of low melting
point; the fourth member of group 14 of
the periodic table. Tin itself is the first distinctly
metallic element of the group even
though it retains some amphoteric properties.
Its electronic structure has outer s2p2
electrons ([Kr]4d105s25p2). The element is
of low abundance in the Earth’s crust
(0.004%) but is widely distributed, largely
as cassiterite (SnOsub>2). The metal has been
known since early bronze age civilizations
when the ores used were relatively rich but
currently worked ores are as low as 1–2% and considerable concentration must be
carried out before roasting. The metal itself
is obtained by reduction using carbon,
SnOsub>2 + C → Sn + COsub>2
Tin is an expensive metal and several
processes are used for recovering tin from
scrap tin-plate. These may involve chlorination
(dry) to the volatile SnCl4, or electrolytic
methods using an alkaline
electrolyte:
Sn+ 4OH-→ Sn(OH)42-+ 2e-(anode)
Sn(OH)42- → Sn2+ + 4OH- (cathode)
Sn2+ + 2e → Sn (cathode)
Tin does not react directly with hydrogen
but an unstable hydride, SnH4, can be
prepared by reduction of SnCl4. The low
stability is due to the rather poor overlap of
the diffuse orbitals of the tin atom with the
small H-orbitals. Tin forms both tin(II)
oxide and tin(IV) oxide. Both are amphoteric,
dissolving in acids to give tin(II) and
tin(IV) salts, and in bases to form stannites
and stannates,
SnO + 4OH- → [SnO3]4-+2H2O
stannite (relatively unstable)
SnO2 + 4OH- → [SnO4]4–+ 2H2O
stannate
The halides, SnX2, may be prepared by
dissolving tin metal in the hydrogen halide
or by the action of heat on SnO plus the hydrogen
halide. Tin(IV) halides may be prepared
by direct reaction of halogen with
the metal. Although tin(II) halides are ionized
in solution their melting points are all
low suggesting considerable covalence in
all but the fluoride. The tin(IV) halides are
volatile and essentially covalent with slight
polarization of the bonds. Tin(II) compounds
are readily oxidized to tin(IV) compounds
and are therefore good reducing
agents for general laboratory use.
Tin has three crystalline modifications
or allotropes, α-tin or ‘gray tin’ (diamond
structure), β-tin or ‘white tin’, and γ-tin;
the latter two are metallic with close
packed structures. Tin also has several isotopes.
It is used in a large number of alloys
including Babbit metal, bell metal, Britannia
metal, bronze, gun metal, and pewter
as well as several special solders.
Symbol: Sn; m.p. 232°C; b.p. 2270°C;
r.d. 7.31 (20°C); p.n. 50; r.a.m. 118.710. | | 調製方法 | Tin is relatively rare, composing only about 0.0006% in the
earth’s crust. The major tin ore is cassiterite, a naturally
occurring tin (IV) oxide (SnO2). The other major tin-containing
minerals are stannate, teallite, cylindrite, and canfieldite
that are sulfides of tin. | | 定義 | Metallic element of atomic
number 50, group IVA of the periodic system, aw
118.69, valences of 2, 4; 10 isotopes. | | 一般的な説明 | White TIN is an almost silver-white, ductile, malleable, lustrous solid. Mp 232°C; bp: 2507°C. Density: 7.3 g cm-3. Pure white TIN becomes non-metallic powdery gray TIN if held for a sustained period at temperatures less than 13°C. | | 反応プロフィール | TIN is a reducing agent. Stable in massive form in air, but oxidizes (corrodes) in air as a powder, especially in the presence of water. Dissolve slowly in dilute strong acids in the cold. Dissolves in hot aqueous KOH and other strongly basic solutions. Incompatible with acids and base. Incompatible with chlorine and turpenTINe. | | 危険性 | Tin, as the elemental metal, is nontoxic. Most, but not all of tin’s inorganic salts and compoundsare also nontoxic.
In contrast, almost all organic tin compounds (tin compounds composed of carbon andhydrocarbons) are very toxic and should be avoided. If they are used, special equipment andcare must be taken in handling.
(Note: When chemical formulas use the letter “R” preceding an element’s symbol, it designatessome form of organic compound—for example, R4Sn. If the letter “X” follows theelement’s symbol in a formula, it designates some form of inorganic compound—for example,SnX2. Thus, a whole series of tin compounds could be designated as R4Sn2, R2Sn, or SnX4,SnX2, and so forth.) | | 健康ハザード | Inorganic tin salts are irritants
of the eyes and skin.
No systemic effects have been reported
from industrial exposure. Some inorganic tin
compounds can cause skin or eye irritation
because of acid or alkaline reaction produced
with water. Tin tetrachloride, stannous chloride,
and stannous sulfate are strong acids;
sodium and potassium stannate are strong alkalies. | | 燃焼性と爆発性 | Non flammable | | 工業用途 | Hot-dip coatings can be applied to fabricatedparts made of mild and alloy steels, cast iron,and copper and copper alloys to improveappearance and corrosion resistance. Like zinc,the coatings consist of two layers — a relativelypure outer layer and an intermediate alloy layer.
An invisible surface film of stannic oxideis formed during exposure, which helps toretard, but does not completely prevent, corrosion.The coatings have good resistance to tarnishingand staining indoors, and in most rural,marine, and industrial atmospheres. They alsoresist foods. Corrosion resistance in all casescan be markedly improved by increasing thicknessand controlling porosity. Typical applicationswhere they can be used are milk cans,condenser and transformer cans, food and beveragecontainers, and various items of sanitaryequipment such as cast iron mincing machinesand grinders. | | 安全性プロファイル | An inhalation hazard.
Questionable carcinogen with experimental
tumorigenic data by implant route.
Combustible in the form of dust when
exposed to heat or by spontaneous chemical
reaction with Br2, BrF3, Cl2, ClF3, Cu(NO3),
K2O2, S. See also POWDERED METALS
and TIN COMPOUNDS. | | 職業ばく露 | The most important use of tin is as a protective coating for other metals, such as in the food and beverage canning industry; in roofing tiles; silverware, coated wire; household utensils; electronic components; and pistons. Common tin alloys are phosphor bronze; light brass; gun metal; high tensile brass; manganese bronze; die-casting alloys; bearing metals; type metal; and pewter. These are used as soft solders, fillers in automobile bodies; and as coatings for hydraulic brake parts; aircraft landing gear and engine parts. Metallic tin is used in the manufacture of collapsible tubes and foil for packaging. Exposures to tin may occur in mining, smelting, and refining; and in the production and use of tin alloys and solders. Inorganic tin compounds are important industrially in the production of ceramics; porcelain, enamel, glass; and inks; in the production of fungicides; anthelmintics, insecticides; as a stabilizer it is used in polyvinyl plastics and chlorinated rubber paints; and it is used in plating baths. | | 用途 | また、錫は鉄よりイオン化傾向が小さく溶出しにくいため、鋼板に錫をめっきしたブリキとして食缶や飲料缶 などの容器、瓶のスクリューキャップ、王冠等に利用されている。その他、錫は電子部品用めっきや塩ビ安定 剤等の化成品、ITO（Indium Tin Oxide：酸化インジウムに酸化錫を添加した化合物）として知られるディスプレ イ用の透明電極にも使用されている。
さらに、銅に錫と少量のリンを加えた合金であるリン青銅は、機械的な強さを持ち、ばね性、耐久性が良い ことから、IC用リードフレームや通信機・計器等に使用されるばねに用いられている他、歯車や軸受けにも使 用される。
錫の鋳造品は食器や花器としても利用される。また、溶融した錫の上に溶融したガラスを浮かべて製板す るフロートガラス製法にも錫は利用されている。 | | 発がん性 | Limited animal testing with stannous chloride
has not revealed evidence of carcinogenic
potential. Mixed results have been observed in
genotoxic assays. | | 環境運命予測 | Tin is a naturally occurring element in the earth’s crust with
~2–3 ppm in concentration and found in environmental
media in both organic and inorganic forms. Tin may be
released to the environment from natural and anthropogenic
sources. The most significant releases of tin are from burning of
fossil fuels and industrial production and use of tin. Tin compounds are generally only sparingly soluble in water and
are likely to partition to soils, sediments, and possibly to
aquatic organisms. Inorganic tin cannot be degraded in the
environment, but may undergo redox reaction, ligand
exchange, and precipitation reactions. Inorganic tin can be
transformed into organometallic forms through the microbial
methylation process. Degradation of organotin compounds
involves the breaking of the tin–carbon bond through UV
irradiation or biological and chemical cleavage. The speciation
of organotin compounds is pH-dependent. In sediment,
organotins are generally persistent. Photodegradation of
organotins may occur at relatively slow rates. Hydrolysis is
considered insignificant. Organotin compounds may be
significantly bioconcentrated by aquatic organisms. Tin has
been historically used in antifouling paints and coatings for
the bottom of boats, but this has been discontinued because
of its extreme toxicity to marine organisms.
A bioconcentration factor (BCF) relates the concentration
of a chemical in plants and animals to the concentration of
the chemical in the medium in which they live. It was estimated
that the BCFs of inorganic tin were 100, 1000, and
3000 for marine and freshwater plants, invertebrates, and fish.
Marine algae can bioconcentrate stannic tin by a factor of
1900. The BCF of tributyltin was estimated to be 473, but
measured BCFs were always higher. Bioconcentration factors
for bis(tributyltin)oxide with marine oysters were measured as
2300–11 400. Seven-day BCFs were derived for seven organotin
compounds for muscle, liver, kidney, and vertebra tissue
of carp. The BCFs ranged from 12 to 5012; the highest factors
were found for tributyltins. However, these factors were not
based on steady-state conditions, and may be low estimates.
No information was obtained on the food chain and biomagnification
of inorganic or organic tin. | | 輸送方法 | UN3089 Metal powders, flammable, n.o.s., Hazard Class: 4.1; Labels: 4.1-Flammable solid. | | 純化方法 | Tin powder is purified by adding it to about twice its weight of 10% aqueousNaOH and shaking vigorously for 10minutes. (This removes oxide film and stearic acid or similar material that is sometimes added for pulverisation.) It is then filtered, washed with water until the washings are no longer alkaline to litmus, rinsed with MeOH and dried in air. [Sisido et al. J Am Chem Soc 83 538 1961.] | | Toxicity evaluation | All organic tin compounds, including trimethyltin, triethyltin,
and tributyltin compounds, have the ability to cause damages
to the structure of Vitamin B12 depletion of methyl group
necessary for DNA and RNA reactions. Due to lipophilicity,
organotin compounds may affect lipid bilayers by altering
membrane fluidity where it is an initial site of activation. Thus,
these compounds can bind to proteins and inhibit mitochondrial
oxidative phosphorylation (hydrolysis of adenosine
triphosphate) and brain glucose oxidation and are toxic. Very
little data are available on inorganic tin. | | 不和合性 | TIN is a reducing agent. Stable in bulk form in air, but as powder it corrodes (oxidizes) in air, especially in the presence of moisture. Keep away from strong oxidizers (chlorates, nitrates, peroxides, permanganates, perchlorates, chlorine, bromine, fluorine, etc.); contact may cause fires or explosions. Incompatible with acids, alkalies, bases, chlorine, turpentine; reacts violently with acetic aldehyde, ammonium nitrate, ammonium perchlorate, hexachloroethane. Strong reducing agents may react violently with halogens, bromine fluoride, chlorine trifluoride, copper nitrate, disulfur dichloride, nitrosyl fluoride, potassium dioxide, sodium peroxide, sulfur, and other chemicals. May form explosive compounds with hexachloroethane, pentachloroethane, picric acid, potassium iodate, potassium peroxide, 2,4,6-trinitrobenzene-1,3,5-triol. |
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