Homophobic propaganda (or anti-gay propaganda) is propaganda based on homonegativity and homophobia towards homosexual and sometimes other non-heterosexual people. Such propaganda supports anti-gay prejudices and stereotypes, and promotes social stigmatization or discrimination. The term homophobic propaganda was used by the historian Stefan Micheler in his work Homophobic Propaganda and the Denunciation of Same-Sex-Desiring Men under National Socialism, as well as other works treating the topic.
In some countries, some forms of homophobic propaganda are considered hate speech and are prohibited by law. Other countries are openly homophobic and treat engaging in homosexual relations as a criminal offence.
Political attitudes towards homosexuals in Nazi Germany
were based on the assumption that homosexuals were destroying the
German nation as "sexual degenerates". Historian Erwin J. Haeberle dates
the first appearance of this political attitude to 14 May 1928.
Categorized as a ‘biocracy’ by Maastricht University professor
Harry Oosterheis, the Nazi regime was primarily concerned with the fact
that homosexual men
could not bear offspring—and therefore could not ultimately contribute
to the spread of the Aryan race. Though homosexuals in Nazi Germany were
not persecuted systematically, researchers estimate that around 50,000
homosexual men were convicted for "unnatural vice", and between 10 and
30% of this proportion were ultimately sent to concentration camps.
In Russia, it is illegal to commit crimes against someone based on
their social group, and LGBT people are considered a separate social
group by law. Responsibility for it is established item 136 and item 282
of the criminal code of the Russian Federation.
However, on 30 June 2013, President Vladimir Putin signed into law a bill banning the "propaganda of nontraditional sexual relations" among minors, and prohibits the equation of same-sex and straight marital relationships. Vice News claims that many LGBT rights groups have been transformed "from being a stigmatized fringe group to full-blown enemies of the state" in Russia following the introduction of this law, and that openly homophobic and neo-Nazi groups such as Occupy Paedophilia have been described by Russian authorities as "civil movements fighting the sins of society".
Norway
In
1981, Norway became the first country to establish a criminal penalty
(a fine or imprisonment for up to two years) for public threats, defamations, expressions of hate, or agitation for discrimination towards the LGBTQ community.
The Netherlands
On
1 July 1987, in the Netherlands joined the Dutch Penal code, which
established punishment for public defamations on the basis of sexual
orientation as fees or imprisonment for up to two years.
Ireland
In
1989 in Ireland a resolution against anti-gay hate speech came into
effect. It establishes penalty in the form of fees or imprisonment for
up to two years for publication or distribution of materials which
contain defamations, threats, hate speech or offenses for LGBT people.
The law is occasionally taken into effect.
Australia
On 2 March 1993, in New South Wales,
Australia, an amendment to the antidiscrimination law came into effect
which prohibits public hate speech, despisement or ridiculing of
homosexuals. A legal exclusion is any information which is distributed
for educational, religious, scientific or social purposes.
On 10 December 1999, an analogous amendment was accepted by Tasmanian parliament, which permits no exclusion.
South Africa
In February 2000 the South African Parliament enacted the Promotion of Equality and Prevention of Unfair Discrimination Act,
which prohibits hate speech based on any of the constitutionally
prohibited grounds, including sexual orientation. The definition of hate
speech includes speech which is intended to "promote or propagate
hatred".
Section 28 of the Local Government Act 1988 added section 2A to the Local Government Act 1986, which forbade local authorities
from being allowed to "promote homosexuality", or "promote the teaching
in any maintained school the acceptability of homosexuality as a
pretended family relationship".
It was repealed on 21 June 2000, in Scotland as one of the first pieces of legislation enacted by the new Scottish Parliament, and on 18 November 2003, in the rest of the United Kingdom by section 122 of the Local Government Act 2003.
Spain
Spain's
antidiscrimination laws have banned hate speech in regards to sexual
orientation and gender identity since 1995. Discrimination, hate, or
violence on the premise of either of the aforementioned factors is
punishable by up to three years in prison.
Poland
Poland's ruling party since 2015, Law and Justice,
has been using anti-LGBT rhetoric increasingly through the national
media, comparing liberalization of LGBT rights to the ideology of the communist regime.
Stigmatizing the acronym "LGBT" as "the Western ideology" has led to
demonizing politically active LGBT people, in contrast to socially
conforming, "normal" LGBT people. Subsequently, "LGBT-free zones" have been introduced in some regions, with the plea of securing the idea of a traditional or Christian family model.
These contrails at an airshow provide evidence regarding the aircraft's flight path.
Evidence for a proposition is what supports the proposition. It is usually understood as an indication that the proposition is true. The exact definition and role of evidence vary across different fields. In epistemology, evidence is what justifiesbeliefs or what makes it rational to hold a certain doxastic
attitude. For example, a perceptual experience of a tree may serve as
evidence to justify the belief that there is a tree. In this role,
evidence is usually understood as a private mental state. In phenomenology,
evidence is limited to intuitive knowledge, often associated with the
controversial assumption that it provides indubitable access to truth.
The relation between evidence and a supported statement can vary in strength, ranging from weak correlation to indisputable proof.
Theories of the evidential relation examine the nature of this
connection. Probabilistic approaches hold that something counts as
evidence if it increases the probability of the supported statement. According to hypothetico-deductivism, evidence consists in observational
consequences of a hypothesis. The positive-instance approach states
that an observation sentence is evidence for a universal statement if
the sentence describes a positive instance of this statement.
Nature of evidence
Notion
Understood in its broadest sense, evidence for a proposition
is what supports this proposition. Traditionally, the term is sometimes
understood in a narrower sense: as the intuitive knowledge of facts
that are considered indubitable.
In this sense, only the singular form is used. This meaning is found
especially in phenomenology, in which evidence is elevated to one of the
basic principles of philosophy, giving philosophy the ultimate
justifications that are supposed to turn it into a rigorous science.In a more modern usage, the plural form is also used. In academic discourse, evidence plays a central role in epistemology and in the philosophy of science.
Reference to evidence is made in many different fields, like in
science, in the legal system, in history, in journalism and in everyday
discourse.
A variety of different attempts have been made to conceptualize the
nature of evidence. These attempts often proceed by starting with
intuitions from one field or in relation to one theoretical role played
by evidence and go on to generalize these intuitions, leading to a
universal definition of evidence.
One important intuition is that evidence is what justifiesbeliefs.
This line of thought is usually followed in epistemology and tends to
explain evidence in terms of private mental states, for example, as
experiences, other beliefs or knowledge. This is closely related to the
idea that how rational someone is, is determined by how they respond to evidence.
Another intuition, which is more dominant in the philosophy of science,
focuses on evidence as that which confirms scientific hypotheses and
arbitrates between competing theories.
On this view, it is essential that evidence is public so that different
scientists can share the same evidence. This leaves publicly observable
phenomena like physical objects and events as the best candidates for
evidence, unlike private mental states.
One problem with these approaches is that the resulting definitions of
evidence, both within a field and between fields, vary a lot and are
incompatible with each other. For example, it is not clear what a bloody
knife and a perceptual experience have in common when both are treated
as evidence in different disciplines. This suggests that there is no
unitary concept corresponding to the different theoretical roles
ascribed to evidence, i.e. that we do not always mean the same thing
when we talk of evidence.
Characteristics
On the other hand, Aristotle, phenomenologists, and numerous scholars accept that there could be several degrees of evidence.
For instance, while the outcome of a complex equation may become more
or less evident to a mathematician after hours of deduction, yet with
little doubts about it, a simpler formula would appear more evident to
them.
Riofrio has detected some characteristics that are present in
evident arguments and proofs. The more they are evident, the more these
characteristics will be present. There are six intrinsic characteristics
of evidence:
The truth lies in what is evident, while falsehood or
irrationality, although it may appear evident at times, lacks true
evidence.
What is evident aligns coherently with other truths acquired through
knowledge. Any insurmountable incoherence would indicate the presence
of error or falsehood.
Evident truths are based on necessary reasoning.
The simplest truths are the most evident. They are self-explanatory
and do not require argumentation to be understood by the intellect.
However, for those lacking education, certain complex truths require
rational discourse to become evident.
Evident truths do not need justification; they are indubitable. They
are intuitively grasped by the intellect, without the need for further
discourse, arguments, or proof.
Evident truths are clear, translucent, and filled with light.
In addition, four subjective or external characteristics can be detected over those things that are more or less evident:
The evident instills certainty and grants the knower a
subjective sense of security, as they believe to have aligned with the
truth
Initially, evident truths are perceived as natural and effortless,
as Aristotle highlighted. They are innately present within the
intellect, fostering a peaceful and harmonious understanding.
Consequently, evident truths appear to be widely shared, strongly
connected to common sense, which comprises generally accepted beliefs.
Evident truths are fertile ground: they provide a solid foundation for other branches of scientific knowledge to flourish.
These ten characteristics of what is evident allowed Riofrio to formulate a test of evidence to detect the level of certainty or evidence that one argument or proof could have.
Different approaches to evidence
Important theorists of evidence include Bertrand Russell, Willard Van Orman Quine, the logical positivists, Timothy Williamson, Earl Conee and Richard Feldman.
Russell, Quine and the logical positivists belong to the empiricist
tradition and hold that evidence consists in sense data, stimulation of
one's sensory receptors and observation statements, respectively. According to Williamson, all and only knowledge constitute evidence. Conee and Feldman hold that only one's current mental states should be considered evidence.
In epistemology
The guiding intuition within epistemology concerning the role of evidence is that it is what justifies beliefs.
For example, Phoebe's auditory experience of the music justifies her
belief that the speakers are on. Evidence has to be possessed by the
believer in order to play this role.
So Phoebe's own experiences can justify her own beliefs but not someone
else's beliefs. Some philosophers hold that evidence possession is
restricted to conscious mental states, for example, to sense data.
This view has the implausible consequence that many of simple
everyday-beliefs would be unjustified. The more common view is that all
kinds of mental states, including stored beliefs that are currently
unconscious, can act as evidence.
It is sometimes argued that the possession of a mental state capable of
justifying another is not sufficient for the justification to happen.
The idea behind this line of thought is that justified belief has to be
connected to or grounded in the mental state acting as its evidence.
So Phoebe's belief that the speakers are on is not justified by her
auditory experience if the belief is not based in this experience. This
would be the case, for example, if Phoebe has both the experience and
the belief but is unaware of the fact that the music is produced by the
speakers.
It is sometimes held that only propositional mental states can play this role, a position known as "propositionalism".
A mental state is propositional if it is an attitude directed at a
propositional content. Such attitudes are usually expressed by verbs
like "believe" together with a that-clause, as in "Robert believes that
the corner shop sells milk".
Such a view denies that sensory impressions can act as evidence. This
is often held as an argument against this view since sensory impressions
are commonly treated as evidence. Propositionalism is sometimes combined with the view that only attitudes to true propositions can count as evidence.
On this view, the belief that the corner shop sells milk only
constitutes evidence for the belief that the corner shop sells dairy
products if the corner shop actually sells milk. Against this position,
it has been argued that evidence can be misleading but still count as
evidence.
This line of thought is often combined with the idea that evidence, propositional or otherwise, determines what it is rational for us to believe. But it can be rational to have a false belief. This is the case when we possess misleading evidence. For example, it was rational for Neo in the Matrix movie
to believe that he was living in the 20th century because of all the
evidence supporting his belief despite the fact that this evidence was
misleading since it was part of a simulated reality. This account of
evidence and rationality can also be extended to other doxastic
attitudes, like disbelief and suspension of belief. So rationality does
not just demand that we believe something if we have decisive evidence
for it, it also demands that we disbelieve something if we have decisive
evidence against it and that we suspend belief if we lack decisive
evidence either way.
In phenomenology
The
meaning of the term "evidence" in phenomenology shows many parallels to
its epistemological usage, but it is understood in a narrower sense.
Thus, evidence here specifically refers to intuitive knowledge, which is
described as "self-given" (selbst-gegeben).
This contrasts with empty intentions, in which one refers to states of
affairs through a certain opinion, but without an intuitive
presentation. This is why evidence is often associated with the controversial thesis that it constitutes an immediate access to truth.
In this sense, the evidently given phenomenon guarantees its own truth
and is therefore considered indubitable. Due to this special
epistemological status of evidence, it is regarded in phenomenology as
the basic principle of all philosophy.
In this form, it represents the lowest foundation of knowledge, which
consists of indubitable insights upon which all subsequent knowledge is
built.
This evidence-based method is meant to make it possible for philosophy
to overcome many of the traditionally unresolved disagreements and thus
become a rigorous science.
This far-reaching claim of phenomenology, based on absolute certainty,
is one of the focal points of criticism by its opponents. Thus, it has
been argued that even knowledge based on self-evident intuition is
fallible. This can be seen, for example, in the fact that even among
phenomenologists, there is much disagreement about the basic structures
of experience.
In science
In the sciences, evidence is understood as what confirms or disconfirmsscientific hypotheses. The term "confirmation" is sometimes used synonymously with that of "evidential support".
Measurements of Mercury's "anomalous" orbit, for example, are seen as
evidence that confirms Einstein's theory of general relativity. This is
especially relevant for choosing between competing theories. So in the
case above, evidence plays the role of neutral arbiter between Newton's and Einstein's theory of gravitation. This is only possible if scientific evidence is public and uncontroversial
so that proponents of competing scientific theories agree on what
evidence is available. These requirements suggest scientific evidence
consists not of private mental states but of public physical objects or events.
It is often held that evidence is in some sense prior to the hypotheses it confirms. This was sometimes understood as temporal priority,
i.e. that we come first to possess the evidence and later form the
hypothesis through induction. But this temporal order is not always
reflected in scientific practice, where experimental researchers may
look for a specific piece of evidence in order to confirm or disconfirm a
pre-existing hypothesis. Logical positivists, on the other hand, held that this priority is semantic
in nature, i.e. that the meanings of the theoretical terms used in the
hypothesis are determined by what would count as evidence for them.
Counterexamples for this view come from the fact that our idea of what
counts as evidence may change while the meanings of the corresponding
theoretical terms remain constant. The most plausible view is that this priority is epistemic
in nature, i.e. that our belief in a hypothesis is justified based on
the evidence while the justification for the belief in the evidence does
not depend on the hypothesis.
A central issue for the scientific conception of evidence is the problem of underdetermination, i.e. that the evidence available supports competing theories equally well.
So, for example, evidence from our everyday life about how gravity
works confirms Newton's and Einstein's theory of gravitation equally
well and is therefore unable to establish consensus among scientists.
But in such cases, it is often the gradual accumulation of evidence that
eventually leads to an emerging consensus. This evidence-driven process
towards consensus seems to be one hallmark of the sciences not shared
by other fields.
Another problem for the conception of evidence in terms of
confirmation of hypotheses is that what some scientists consider the
evidence to be may already involve various theoretical assumptions not
shared by other scientists. This phenomenon is known as theory-ladenness.
Some cases of theory-ladenness are relatively uncontroversial, for
example, that the numbers output by a measurement device need additional
assumptions about how this device works and what was measured in order
to count as meaningful evidence. Other putative cases are more controversial, for example, the idea that different people or cultures perceive the world through different, incommensurableconceptual schemes, leading them to very different impressions about what is the case and what evidence is available.
Theory-ladenness threatens to impede the role of evidence as neutral
arbiter since these additional assumptions may favor some theories over
others. It could thereby also undermine a consensus to emerge since the different parties may be unable to agree even on what the evidence is.
When understood in the widest sense, it is not controversial that some
form of theory-ladenness exists. But it is questionable whether it
constitutes a serious threat to scientific evidence when understood in
this sense.
Nature of the evidential relation
Philosophers
in the 20th century started to investigate the "evidential relation",
the relation between evidence and the proposition supported by it.
The issue of the nature of the evidential relation concerns the
question of what this relation has to be like in order for one thing to
justify a belief or to confirm a hypothesis. Important theories in this field include the probabilistic approach, hypothetico-deductivism and the positive-instance approach.
Probabilistic approaches, also referred to as Bayesian confirmation theory,
explain the evidential relation in terms of probabilities. They hold
that all that is necessary is that the existence of the evidence
increases the likelihood that the hypothesis is true. This can be
expressed mathematically as .
In words: a piece of evidence (E) confirms a hypothesis (H) if the
conditional probability of this hypothesis relative to the evidence is
higher than the unconditional probability of the hypothesis by itself.
Smoke (E), for example, is evidence that there is a fire (H), because
the two usually occur together, which is why the likelihood of fire
given that there is smoke is higher than the likelihood of fire by
itself. On this view, evidence is akin to an indicator or a symptom of
the truth of the hypothesis.
Against this approach, it has been argued that it is too liberal
because it allows accidental generalizations as evidence. Finding a
nickel in one's pocket, for example, raises the probability of the
hypothesis that "All the coins in my pockets are nickels". But,
according to Alvin Goldman,
it should not be considered evidence for this hypothesis since there is
no lawful connection between this one nickel and the other coins in the
pocket.
Hypothetico-deductivism
is a non-probabilistic approach that characterizes the evidential
relations in terms of deductive consequences of the hypothesis.
According to this view, "evidence for a hypothesis is a true observational consequence of that hypothesis".
One problem with the characterization so far is that hypotheses usually
contain relatively little information and therefore have few if any
deductive observational consequences. So the hypothesis by itself that
there is a fire does not entail that smoke is observed. Instead, various
auxiliary assumptions have to be included about the location of the
smoke, the fire, the observer, the lighting conditions, the laws of
chemistry, etc. In this way, the evidential relation becomes a
three-place relation between evidence, hypothesis and auxiliary
assumptions. This means that whether a thing is evidence for a hypothesis depends on
the auxiliary assumptions one holds. This approach fits well with
various scientific practices. For example, it is often the case that
experimental scientists try to find evidence that would confirm or
disconfirm a proposed theory. The hypothetico-deductive approach can be
used to predict what should be observed in an experiment if the theory
was true. It thereby explains the evidential relation between the experiment and the theory.
One problem with this approach is that it cannot distinguish between
relevant and certain irrelevant cases. So if smoke is evidence for the
hypothesis "there is fire", then it is also evidence for conjunctions
including this hypothesis, for example, "there is fire and Socrates was
wise", despite the fact that Socrates's wisdom is irrelevant here.
According to the positive-instance approach, an
observation sentence is evidence for a universal hypothesis if the
sentence describes a positive instance of this hypothesis.
For example, the observation that "this swan is white" is an instance
of the universal hypothesis that "all swans are white". This approach
can be given a precise formulation in first-order logic: a proposition is evidence for a hypothesis if it entails the "development of the hypothesis".
Intuitively, the development of the hypothesis is what the hypothesis
states if it was restricted to only the individuals mentioned in the
evidence. In the case above, we have the hypothesis ""
(all swans are white) which, when restricted to the domain "{a}",
containing only the one individual mentioned in the evidence, entails
the evidence, i.e. "" (this swan is white).
One important shortcoming of this approach is that it requires that the
hypothesis and the evidence are formulated in the same vocabulary, i.e.
use the same predicates, like "" or ""
above. But many scientific theories posit theoretical objects, like
electrons or strings in physics, that are not directly observable and
therefore cannot show up in the evidence as conceived here.
In scientific research evidence is accumulated through observations
of phenomena that occur in the natural world, or which are created as experiments in a laboratory or other controlled conditions. Scientists tend to focus on how the data used during statistical inference are generated. Scientific evidence usually goes towards supporting or rejecting a hypothesis.
The burden of proof is on the person making a contentious claim.
Within science, this translates to the burden resting on presenters of a
paper, in which the presenters argue for their specific findings. This
paper is placed before a panel of judges where the presenter must defend
the thesis against all challenges.
When evidence is contradictory to predicted expectations, the
evidence and the ways of making it are often closely scrutinized (see experimenter's regress) and only at the end of this process is the hypothesis rejected: this can be referred to as 'refutation of the hypothesis'. The rules for evidence used by science are collected systematically in an attempt to avoid the bias inherent to anecdotal evidence.
Law
The balance scales seen in depictions of Lady Justice can be seen as representing the weighing of evidence in a legal proceeding.
In law, the production and presentation of evidence depend first on establishing on whom the burden of proof lies. Admissible evidence
is that which a court receives and considers for the purposes of
deciding a particular case. Two primary burden-of-proof considerations
exist in law. The first is on whom the burden rests. In many,
especially Western, courts, the burden of proof is placed on the
prosecution in criminal cases and the plaintiff in civil cases. The
second consideration is the degree of certitude proof must reach,
depending on both the quantity and quality of evidence. These degrees
are different for criminal and civil cases, the former requiring
evidence beyond a reasonable doubt, the latter considering only which side has the preponderance of evidence, or whether the proposition is more likely true or false.
The parts of a legal case that are not in controversy are known,
in general, as the "facts of the case." Beyond any facts that are
undisputed, a judge or jury is usually tasked with being a trier of fact for the other issues of a case. Evidence and rules are used to decide questions of fact that are disputed, some of which may be determined by the legal burden of proof relevant to the case. Evidence in certain cases (e.g. capital crimes)
must be more compelling than in other situations (e.g. minor civil
disputes), which drastically affects the quality and quantity of
evidence necessary to decide a case. The decision-maker, often a jury,
but sometimes a judge decides whether the burden of proof has been
fulfilled. After deciding who will carry the burden of proof, the
evidence is first gathered and then presented before the court:
Collection
An FBI Evidence Response Team gathering evidence by dusting an area for fingerprints
In a criminal investigation, rather than attempting to prove an
abstract or hypothetical point, the evidence gatherers attempt to
determine who is responsible for a criminal act. The focus of criminal evidence is to connect physical evidence and reports of witnesses to a specific person.
Presentation
The path that physical evidence takes from the scene of a crime or the arrest of a suspect to the courtroom is called the chain of custody.
In a criminal case, this path must be clearly documented or attested to
by those who handled the evidence. If the chain of evidence is broken, a
defendant may be able to persuade the judge to declare the evidence inadmissible.
Presenting evidence before the court differs from the gathering
of evidence in important ways. Gathering evidence may take many forms;
presenting evidence that tends to prove or disprove the point at issue
is strictly governed by rules. Failure to follow these rules leads to
any number of consequences. In law, certain policies allow (or require)
evidence to be excluded from consideration based either on indicia
relating to reliability, or broader social concerns. Testimony (which
tells) and exhibits (which show) are the two main categories of evidence
presented at a trial or hearing. In the United States, evidence in
federal court is admitted or excluded under the Federal Rules of Evidence.
The burden of proof is the obligation of a party in an
argument or dispute to provide sufficient evidence to shift the other
party's or a third party's belief from their initial position. The
burden of proof must be fulfilled by both establishing confirming
evidence and negating oppositional evidence. Conclusions drawn from
evidence may be subject to criticism based on a perceived failure to
fulfill the burden of proof.
Two principal considerations are:
On whom does the burden of proof rest?
To what degree of certitude must the assertion be supported?
The latter question depends on the nature of the point under
contention and determines the quantity and quality of evidence required
to meet the burden of proof.
In a criminal trial in the United States, for example, the prosecution carries the burden of proof since the defendant is presumed innocent until proven guilty beyond a reasonable doubt. Similarly, in most civil procedures, the plaintiff
carries the burden of proof and must convince a judge or jury that the
preponderance of the evidence is on their side. Other legal standards of
proof include "reasonable suspicion", "probable cause" (as for arrest), "prima facie evidence", "credible evidence", "substantial evidence", and "clear and convincing evidence".
In a philosophical debate,
there is an implicit burden of proof on the party asserting a claim,
since the default position is generally one of neutrality or unbelief.
Each party in a debate will therefore carry the burden of proof for any
assertion they make in the argument, although some assertions may be
granted by the other party without further evidence. If the debate is
set up as a resolution to be supported by one side and refuted by another, the overall burden of proof is on the side supporting the resolution.
Bismuth used to be considered the element with the highest atomic
mass whose nuclei do not spontaneously decay. However, in 2003 it was
discovered to be extremely weakly radioactive. The metal's only primordial isotope, bismuth-209, undergoes alpha decay with a half-life about a billion times the estimated age of the universe.
Bismuth metal has been known since ancient times. Before modern
analytical methods bismuth's metallurgical similarities to lead and tin
often led it to be confused with those metals. The etymology of
"bismuth" is uncertain. The name may come from mid-sixteenth century Neo-Latin translations of the German words weiße Masse or Wismuth, meaning 'white mass', which were rendered as bisemutum or bisemutium.
Bismuth compounds account for about half the global production of bismuth. They are used in cosmetics; pigments; and a few pharmaceuticals, notably bismuth subsalicylate, used to treat diarrhea.
Bismuth's unusual propensity to expand as it solidifies is responsible
for some of its uses, as in the casting of printing type. Bismuth, when in its elemental form, has unusually low toxicity for a heavy metal. As the toxicity of lead and the cost of its environmental remediation became more apparent during the 20th century, suitable bismuth alloys
have gained popularity as replacements for lead. Presently, around a
third of global bismuth production is dedicated to needs formerly met by
lead.
History and etymology
Bismuth metal has been known since ancient times and it was one of the first 10 metals to have been discovered. The name bismuth dates to around 1665 and is of uncertain etymology. The name possibly comes from obsolete German Bismuth, Wismut, Wissmuth (early 16th century), perhaps related to Old High Germanhwiz ("white"). The Neo-Latinbisemutium (coined by Georgius Agricola, who Latinized many German mining and technical words) is from the German Wismuth, itself perhaps from weiße Masse, meaning "white mass".
The element was confused in early times with tin and lead because
of its resemblance to those elements. Because bismuth has been known
since ancient times, no one person is credited with its discovery. Agricola
(1546) states that bismuth is a distinct metal in a family of metals
including tin and lead. This was based on observation of the metals and
their physical properties.
Miners in the age of alchemy also gave bismuth the name tectum argenti, or "silver being made" in the sense of silver still in the process of being formed within the Earth.
Bismuth was also known to the Incas and used (along with the usual copper and tin) in a special bronze alloy for knives.
Left: A bismuth hopper crystal exhibiting the stairstep crystal structure and iridescent colors, which are produced by interference of light within the oxide film on its surface. Right: a 1 cm3 cube of unoxidised bismuth metal
Physical characteristics
Pressure-temperature phase diagram of bismuth. TC refers to the superconducting transition temperature
Bismuth is a brittle metal with a dark, silver-pink hue, often with an iridescentoxide
tarnish showing many colors from yellow to blue. The spiral,
stair-stepped structure of bismuth crystals is the result of a higher
growth rate around the outside edges than on the inside edges. The
variations in the thickness of the oxide layer that forms on the surface
of the crystal cause different wavelengths of light to interfere upon
reflection, thus displaying a rainbow of colors. When burned in oxygen, bismuth burns with a blue flame and its oxide forms yellow fumes. Its toxicity is much lower than that of its neighbors in the periodic table, such as lead and antimony.
Though virtually unseen in nature, high-purity bismuth can form distinctive, colorful hopper crystals.
It is relatively nontoxic and has a low melting point just above 271 °C
(520 °F), so crystals may be grown using a household stove, although
the resulting crystals will tend to be of lower quality than lab-grown
crystals.
At ambient conditions, bismuth shares the same layered structure as the metallic forms of arsenic and antimony, crystallizing in the rhombohedral lattice. When compressed at room temperature, this Bi–I structure changes first to the monoclinic Bi-II at 2.55 GPa, then to the tetragonal Bi-III at 2.7 GPa, and finally to the body-centered cubic
Bi-V at 7.7 GPa. The corresponding transitions can be monitored via
changes in electrical conductivity; they are rather reproducible and
abrupt and are therefore used for calibration of high-pressure
equipment.
Chemical characteristics
Bismuth
is stable to both dry and moist air at ordinary temperatures. When
red-hot, it reacts with water to make bismuth(III) oxide.
2 Bi + 3 H2O → Bi2O3 + 3 H2
It reacts with fluorine to form bismuth(V) fluoride at 500 °C (932 °F) or bismuth(III) fluoride at lower temperatures (typically from Bi melts); with other halogens it yields only bismuth(III) halides. The trihalides are corrosive and easily react with moisture, forming oxyhalides with the formula BiOX.
The only primordial isotope of bismuth, bismuth-209, was regarded as the heaviest stable nuclide, but it had long been suspected to be unstable on theoretical grounds. This was finally demonstrated in 2003, when researchers at the Institut d'astrophysique spatiale in Orsay, France, measured the alpha (α) decayhalf-life of 209Bi to be 2.01×1019 years (3 Bq/Mg), over 109 times longer than the estimated age of the universe.
Due to its hugely long half-life, for all known medical and industrial
applications, bismuth can be treated as stable. The radioactivity is of
academic interest because bismuth is one of a few elements whose
radioactivity was suspected and theoretically predicted before being
detected in the laboratory. Bismuth has the longest known α-decay half-life, though tellurium-128 has a double beta decay half-life of over 2.2×1024 years.
Six isotopes of bismuth with short half-lives (210–215 inclusive) occur in the natural radioactive decay chains of actinium, radium, thorium, and neptunium; and more have been synthesized. (Though all primordial 237Np has long since decayed, it is continually regenerated by (n,2n) knockout reactions on natural 238U.)
Commercially, bismuth-213 can be produced by bombarding radium with bremsstrahlung photons from a linear particle accelerator.
In 1997, an antibody conjugate with bismuth-213, which has a 45-minute
half-life and α-decays, was used to treat leukemia patients. This
isotope has also been tried in cancer treatment, for example, in the targeted alpha therapy (TAT) program.
Chemically, bismuth resembles arsenic and antimony, but is much less toxic. In almost all known compounds, bismuth has oxidation state +3; a few have states +5 or −3.
The trioxide and trisulfide can both be made from the elements, although the trioxide is extremely corrosive at high temperatures. The pentoxide is not stable at room temperature, and will evolve O 2 gas if heated. Both oxides form complex anions, and NaBiO3 is a strong oxidising agent. The trisulfide is common in bismuth ore.
Similarly, bismuth forms all possible trihalides, but the only pentahalide is BiF5. All are Lewis acids. Bismuth forms several formally-BiI halides; these are complex salts with unusually-structured polyatomic cations and anions.
Bismuth oxychloride (BiOCl) structure (mineral bismoclite). Bismuth atoms are shown as grey, oxygen red, chlorine green.
In strongly acidic aqueous solution, the Bi3+ ion solvates to form Bi(H 2O)3+ 8. As pH increases, the cations polymerize until the octahedral bismuthyl complex [Bi 6O 4(OH) 4]6+ , often abbreviated BiO+. Although bismuth oxychloride and bismuth oxynitrate have stoichiometries suggesting the ion, they are double salts instead. Bismuth nitrate (not oxynitrate) is one of the few aqueous-insoluble nitrate salts.
Bismuth forms very few stable bismuthides, intermetallic compounds in which it attains oxidation state −3. The hydride spontaneously decomposes at room temperature and stabilizes only below −60 °C (−76 °F). Sodium bismuthide has interest as a topologicalDirac insulator.
The reported abundance of bismuth in the Earth's crust varies
significantly by source from 180ppb (similar to that of silver) to 8ppb
(twice as common as gold). The most important ores of bismuth are bismuthinite and bismite. Native bismuth is known from Australia, Bolivia, and China.
World bismuth production, 2022, in tonnes
Country
Refining
China
16,000
Laos
2,000
South Korea
950
Japan
480
Kazakhstan
220
Other
350
Total
20,000
According to the United States Geological Survey
(USGS), 10,200 tonnes of bismuth were produced worldwide by mining and
17,100 tonnes by refining in 2016. Since then, USGS does not provide
mining data for bismuth, considering them unreliable. Globally, bismuth
is mostly produced by refining, as a byproduct of extraction of other
metals such as lead, copper, tin, molybdenum and tungsten, though the refining-to-mining ratio depends on the country.
Bismuth travels in crude lead bullion (which can contain up to
10% bismuth) through several stages of refining, until it is removed by
the Kroll-Betterton process which separates the impurities as slag, or the electrolytic Betts process. Bismuth will behave similarly with another of its major metals, copper.
The raw bismuth metal from both processes contains still considerable
amounts of other metals, foremost lead. By reacting the molten mixture
with chlorine gas the metals are converted to their chlorides while
bismuth remains unchanged. Impurities can also be removed by various
other methods for example with fluxes and treatments yielding
high-purity bismuth metal (over 99% Bi).
Price
World mine production and annual averages of bismuth price (New York, not adjusted for inflation).
The price for pure bismuth metal was relatively stable through most
of the 20th century, except for a spike in the 1970s. Bismuth has always
been produced mainly as a byproduct of lead refining, and thus the
price usually reflected the cost of recovery and the balance between
production and demand.
Before World War II, demand for bismuth was small and mainly
pharmaceutical—bismuth compounds were used to treat such conditions as
digestive disorders, sexually transmitted diseases and burns. Minor amounts of bismuth metal were consumed in fusible alloys for fire sprinkler systems and fuse wire. During World War II bismuth was considered a strategic material,
used for solders, fusible alloys, medications and atomic research. To
stabilize the market, the producers set the price at $1.25 per pound
($2.75 /kg) during the war and at $2.25 per pound ($4.96 /kg) from 1950
until 1964.
In the early 1970s, the price rose rapidly due to increasing
demand for bismuth as a metallurgical additive to aluminium, iron and
steel. This was followed by a decline owing to increased world
production, stabilized consumption, and the recessions of 1980 and
1981–1982. In 1984, the price began to climb as consumption increased
worldwide, especially in the United States and Japan. In the early
1990s, research began on the evaluation of bismuth as a nontoxic
replacement for lead in ceramic glazes, fishing sinkers, food-processing
equipment, free-machining brasses for plumbing applications, lubricating greases, and shot for waterfowl hunting.
Growth in these areas remained slow during the middle 1990s, in spite
of the backing of lead replacement by the United States federal
government, but intensified around 2005. This resulted in a rapid and
continuing increase in price.
Recycling
Most
bismuth is produced as a byproduct of other metal-extraction processes
including the smelting of lead, and also of tungsten and copper. Its sustainability is dependent on increased recycling, which is problematic.
It was once believed that bismuth could be practically recycled
from the soldered joints in electronic equipment. Recent efficiencies in
solder application in electronics mean there is substantially less
solder deposited, and thus less to recycle. While recovering the silver
from silver-bearing solder may remain economic, recovering bismuth is
substantially less so.
18th-century engraving of bismuth processing. During this era, bismuth was used to treat some digestive complaints.
Bismuth has few commercial applications, and those applications that
use it generally require small quantities relative to other raw
materials. In the United States, for example, 733 tonnes of bismuth were
consumed in 2016, of which 70% went into chemicals (including
pharmaceuticals, pigments, and cosmetics) and 11% into bismuth alloys.
In the early 1990s, researchers began to evaluate bismuth as a nontoxic replacement for lead in various applications.
Medicines
Bismuth is an ingredient in some pharmaceuticals, although the use of some of these substances is declining.
Bismuth compounds (including sodium bismuth tartrate) were formerly used to treat syphilis. Arsenic
combined with either bismuth or mercury was a mainstay of syphilis
treatment from the 1920s until the advent of penicillin in 1943.
Bismuth oxychloride (BiOCl) is sometimes used in cosmetics, as a pigment in paint for eye shadows, hair sprays and nail polishes.
This compound is found as the mineral bismoclite and in crystal form
contains layers of atoms (see figure above) that refract light
chromatically, resulting in an iridescent appearance similar to nacre of pearl. It was used as a cosmetic in ancient Egypt and in many places since. Bismuth white (also "Spanish white") can refer to either bismuth oxychloride or bismuth oxynitrate (BiONO3), when used as a white pigment. Bismuth vanadate
is used as a light-stable non-reactive paint pigment (particularly for
artists' paints), often as a replacement for the more toxic cadmium
sulfide yellow and orange-yellow pigments. The most common variety in
artists' paints is a lemon yellow, visually indistinguishable from its
cadmium-containing alternative.
Metal and alloys
Bismuth is used in alloys with other metals such as tin and lead. Wood's metal,
an alloy of bismuth, lead, tin, and cadmium is used in automatic
sprinkler systems for fires. It forms the largest part (50%) of Rose's metal, a fusible alloy, which also contains 25–28% lead and 22–25% tin. It was also used to make bismuth bronze, which was used during the Bronze Age, having been found in Inca knives at Machu Picchu.
Lead replacement
The density difference between lead (11.32 g/cm3) and bismuth (9.78 g/cm3) is small enough that for many ballistics and weighting applications, bismuth can substitute for lead. For example, it can replace lead as a dense material in fishing sinkers. It has been used as a replacement for lead in shot, bullets and less-lethalriot gun
ammunition. The Netherlands, Denmark, England, Wales, the United
States, and many other countries now prohibit the use of lead shot for
the hunting of wetland birds, as many birds are prone to lead poisoning
owing to mistaken ingestion of lead (instead of small stones and grit)
to aid digestion, or even prohibit the use of lead for all hunting, such
as in the Netherlands. Bismuth-tin alloy shot is one alternative that
provides similar ballistic performance to lead.
Bismuth, as a dense element of high atomic weight, is used in
bismuth-impregnated latex shields to shield from X-ray in medical
examinations, such as CTs, mostly as it is considered non-toxic.
The European Union's Restriction of Hazardous Substances Directive
(RoHS) for reduction of lead has broadened bismuth's use in electronics
as a component of low-melting point solders, as a replacement for
traditional tin-lead solders.
Its low toxicity will be especially important for solders to be used in
food processing equipment and copper water pipes, although it can also
be used in other applications including those in the automobile
industry, in the European Union, for example.
Bismuth has been evaluated as a replacement for lead in free-machining brasses for plumbing applications, although it does not equal the performance of leaded steels.
Other metal uses and specialty alloys
Many bismuth alloys have low melting points and are found in specialty applications such as solders.
Many automatic sprinklers, electric fuses, and safety devices in fire
detection and suppression systems contain the eutectic In19.1-Cd5.3-Pb22.6-Sn8.3-Bi44.7 alloy that melts at 47 °C (117 °F)
This is a convenient temperature since it is unlikely to be exceeded in
normal living conditions. Low-melting alloys, such as Bi-Cd-Pb-Sn alloy
which melts at 70 °C (158 °F), are also used in automotive and aviation
industries. Before deforming a thin-walled metal part, it is filled
with a melt or covered with a thin layer of the alloy to reduce the
chance of breaking. Then the alloy is removed by submerging the part in
boiling water.
Bismuth is used to make free-machining steels
and free-machining aluminium alloys for precision machining properties.
It has similar effect to lead and improves the chip breaking during
machining. The shrinking on solidification in lead and the expansion of
bismuth compensate each other and therefore lead and bismuth are often
used in similar quantities.
Similarly, alloys containing comparable parts of bismuth and lead
exhibit a very small change (on the order 0.01%) upon melting,
solidification or aging. Such alloys are used in high-precision casting,
e.g. in dentistry, to create models and molds. Bismuth is also used as an alloying agent in production of malleable irons and as a thermocouple material.
Bismuth is also used in aluminium-silicon cast alloys to refine
silicon morphology. However, it indicated a poisoning effect on
modification of strontium. Some bismuth alloys, such as Bi35-Pb37-Sn25, are combined with non-sticking materials such as mica, glass and enamels
because they easily wet them allowing to make joints to other parts.
Addition of bismuth to caesium enhances the quantum yield of caesium
cathodes. Sintering of bismuth and manganese powders at 300 °C (572 °F) produces a permanent magnet and magnetostrictive material, which is used in ultrasonic generators and receivers working in the 10–100 kHz range and in magnetic and holographic memory devices.
Bismuth is included in BSCCO
(bismuth strontium calcium copper oxide), which is a group of similar
superconducting compounds discovered in 1988 that exhibit the highest
superconducting transition temperatures.
Bismuth telluride is a semiconductor and an excellent thermoelectric material. Bi2Te3 diodes are used in mobile refrigerators, CPU coolers, and as detectors in infrared spectrophotometers.
Bismuth oxide,
in its delta form, is a solid electrolyte for oxygen. This form
normally breaks down below a high-temperature threshold, but can be
electrodeposited well below this temperature in a highly alkaline
solution.
Bismuth germanate is a scintillator, widely used in X-ray and gamma ray detectors.
Bismuth vanadate is an opaque yellow pigment used by some artists' oil, acrylic, and watercolor paint companies, primarily as a replacement for the more toxic cadmium sulfide
yellows in the greenish-yellow (lemon) to orange-toned yellow range. It
performs practically identically to the cadmium pigments, such as in
terms of resistance to degradation from UV exposure, opacity, tinting
strength, and lack of reactivity when mixed with other pigments. The
most commonly-used variety by artists' paint makers is lemon in color.
In addition to being a replacement for several cadmium yellows, it also
serves as a non-toxic visual replacement for the older chromate pigments
made with zinc, lead, and strontium. If a green pigment and barium
sulfate (for increased transparency) are added it can also serve as a
replacement for barium chromate, which possesses a more greenish cast than the others. In comparison with lead chromate, it does not blacken due to hydrogen sulfide
in the air (a process accelerated by UV exposure) and possesses a
particularly brighter color than them, especially the lemon, which is
the most translucent, dull, and fastest to blacken due to the higher
percentage of lead sulfate required to produce that shade. It is also
used, on a limited basis due to its cost, as a vehicle paint pigment.
As catalyst for the fluorination of arylboronic pinacol esters
through a Bi(III)/Bi(V) catalytic cycle, mimicking transition metals in
electrophilic fluorination.
Toxicology and ecotoxicology
See also bismuthia, a rare dermatological condition that results from the prolonged use of bismuth.
Scientific literature indicates that some of the compounds of bismuth
are less toxic to humans via ingestion than other heavy metals (lead,
arsenic, antimony, etc.) presumably due to the comparatively low solubility of bismuth salts. Its biological half-life
for whole-body retention is reported to be 5 days but it can remain in
the kidney for years in people treated with bismuth compounds.
Bismuth poisoning can occur and has according to some reports been common in relatively recent times.As with lead, bismuth poisoning can result in the formation of a black deposit on the gingiva, known as a bismuth line. Poisoning may be treated with dimercaprol; however, evidence for benefit is unclear.
Bismuth's environmental impacts are not well known; it may be
less likely to bioaccumulate than some other heavy metals, and this is
an area of active research.