Selenium metallicum 200c
Sel.
Memory is a net; one finds it full of fish when he takes it from the brook, but a dozen miles of water have run through it without sticking.
[Oliver Wendell Holmes, Sr.]
Signs
Selenium.
CLASSIFICATION Selenium is a metalloid element in group 16 of the periodic table, along with the lighter elements oxygen and sulphur, and the heavier tellurium and polonium. It was discovered in 1817 by the Swedish chemist Berzelius. He named it after selene, the moon, because he found it associated with tellurium, an element named for the earth [tellus = earth]. [An element discovered in the 13th century and described by an Italian scholar as 'red sulphur' is now supposed to have been amorphous selenium.] As a metalloid it stands between metals and non-metals, that is, it has properties of both but equals neither of them. Selenium occasionally occurs uncombined, usually in conjunction with free sulphur; it is more commonly found together with the sulphides as the selenides in ores of such metals as iron, lead, silver, and copper. It is found in small quantities in a few rare minerals, such as clausthalite [with lead], naumannite [with lead and silver], crooksite [with copper and thallium] and tiemannite [with mercury]. In commerce, the element is obtained from the slimes and sludges formed in producing sulphuric acid, and from the anode muds from electrolytic copper, nickel, or silver refineries. Other sources are the flue dusts remaining from processing copper sulphide ores or from lead production, and the gases formed in roasting pyrites [iron disulphides]. The mineral called selenite is in fact a variety of gypsum [calcium sulphate] with broad transparent crystals; it got its name because the ancients believed it to wax and wane with the moon.
FEATURES Selenium exists in three main forms: amorphous, crystalline, and metallic. These forms have two colour varieties: red and greyish black. It is red in the powdered amorphous form and ruby red in the crystalline form; in its glassy amorphous form and when metallic it is black or greyish, respectively. Brought to its boiling point the element forms dark red vapours; liquid selenium is a brownish red. The element resembles sulphur both in its various forms and in its compounds. The metallic form is the most stable under ordinary conditions, whereas the other forms very slowly convert to the metallic form at room temperature. Due to its affinity for hydrogenium, with which it combines directly, selenium manifests a distinct tendency to form acids in the higher valences, of which selenic acid is as strong as sulphuric acid. It combines directly with the halogens, excluding iodine, and reacts with many metals. Selenium burns in air with a bright blue flame forming the dioxide and emitting a characteristic odour resembling rotten horseradish. [Group 16 comprises malodorous elements: oxygen has a pungent smell in its triatomic form as ozone; burnt sulphur gives off a pungent odour; burnt selenium smells of rotten horseradish; tellurium emits a garlicky odour; polonium is a product of the decay of radium. The members of neighbouring group 15 are no less smelly. Itself an odourless gas, nitrogen is essential for the formation of ammonia; phosphorus and arsenic smell of garlic; the heaviest members, antimony and bismuth, are relatively odourless. With the exception of the inert nitrogen, all members of both groups share the property of allotropy: they exist in more than one form.] Vitreous or glassy selenium is formed by rapid cooling of the molten element; it softens at 50-60o C and becomes elastic at 70o C. The other amorphous form, consisting of red powder, is formed by condensation of selenium vapour on a cold surface.
PROPERTIES Selenium's most remarkable properties are related to light and electricity. The element, in its metallic form, is able to convert light directly into electricity. It also changes one type of electricity [alternating current] into another [direct current]. In addition, it exhibits photoconductive action: increased illumination decreases its electrical resistance more than 1,000-fold. These properties makes selenium useful in the production of photoelectric cells, solar cells, and exposure meters for photographic use. "The electrical resistivity of selenium varies over a tremendous range, depending upon such variables as the nature of the allotrope, impurities, the method of refining, temperature, and pressure. Most metals are insoluble in selenium, and non-metallic impurities increase the resistivity. Illumination of crystalline selenium for 0.001 second increases its conductivity by a factor of 10 to 15 times. Red light is more effective than light of shorter wave length."1
USES As photoelectric cells, solar cells, and photographic exposure meters the photoconductive and photosensitive properties of selenium are utilized in devices that translate variations in light intensity into electric current and thence to visual, magnetic, or mechanical effects. Alarm devices, mechanical opening and closing devices, safety systems, counting devices, electronic control systems in factory assembly lines, industrial colour perceptors, television, sound films and xerography depend upon such properties. In devices as dynamos and all sorts of generators the element is used for electric power generation. The glass industry is another user of selenium. Added in small amounts to glass, selenium serves as a decolourizer by eliminating the green tinge produced by traces of iron; incorporated in larger amounts it is used to make glass of a clear red colour such as in signal lamps and traffic lights. The dark ['black'] glass used in windows or walls of buildings, to reduce glare and transmission of solar heat, also contains selenium compounds. The element is also employed in the manufacture of red enamels for ceramics and steel ware, and of pigments for plastics, pains, inks and rubber, as well as for the vulcanization of rubber to increase resistance to abrasion. Selenium sulphide is used in shampoos for the treatment of dandruff and seborrhoeic dermatitis of the scalp; the compound is highly toxic if taken internally.
TOXICOLOGY Toxic intake of selenium is believed to be 10-35 mg, although some authorities mention amounts as low as 5 mg. These differences may be explained by the fact that the toxic potential for selenium and selenium compounds is related to their chemical form and to solubility. Selenates [salts of selenic acid; selenium in valency 6] are relatively soluble compounds, similar to sulphates, and are readily taken up by biological systems. Selenites [salts of selenious acid; selenium in valency 4] and elemental selenium are virtually insoluble and are regarded to be inert. Selenium is thought to interfere with sulphur compounds and even replace the sulphur in the body, as these two minerals are very similar biochemically, and thus may decrease a number of enzyme actions. Some compounds, e.g. hydrogen selenide, are extremely toxic and resemble arsenic in their physiological reactions. Hydrogen selenide - a foul-smelling gas - is a cumulative poison and in a concentration of 1.5 ppm is intolerable to man. Grasses, grains and most weeds do not accumulate selenium even when grown in high-selenium areas, but certain other plants are able to absorb and accumulate selenium compounds in sufficient quantities to make them poisonous to animals. These plants include species of Aster, numerous species of Astragalus [locoweed or milk vetch], species of Atriplex [orach or salt bush], and Grindelia squarrosa, amongst others. 'Blind staggers' is one type of disease in cattle, sheep, and horses attributed to selenium poisoning. The disease is characterized by impairment of vision, dulness, loss of muscular control, irregularity in gait and eating, tendency to wander in circles, and loss of flesh. The animal becomes solitary in habit and eventually ceases to eat and dies [from respiratory failure]. A more chronic syndrome, known as 'alkali disease', has been described in livestock and horses. It is characterized by loss of vitality, emaciation, deformity and shedding of hoofs, loss of long hair, and erosion of joints of long bones. Similar syndromes appear in sheep and dogs. In humans, symptoms of excess intake include dental caries, lassitude, depression, irritability, pallor, skin depigmentation, and a garlic odour to the breath. Klaassen refers to a study of 70 families "living in three counties of South Dakota and in one county of northern Nebraska, from farms where alkali disease in cattle had been recognized, found bad teeth, a yellowish discolouration of the skin, skin eruptions, and diseased nails of the fingers and toes in various family members. A syndrome now believed to be the result of selenium intoxication was discovered in 1961 to affect about 50% of 248 inhabitants of five villages in the Hubei province of China. There are similarities between this syndrome and the chronic effects in livestock and horses. The main symptoms were brittle hair with intact follicles, brittle nails with spots and streaks, and skin lesions on the back of hands and feet and on the forearms, legs, and the back of the neck. These areas were red and swollen, and contained blisters. In addition, 13 of 22 people in one village had neurological symptoms including peripheral anaesthesia, pain, and hyperreflexia. In some individuals these symptoms progressed to numbness, convulsions, paralysis, and altered motor function Selenium has produced loss of fertility and congenital defects and is considered embryotoxic and teratogenic on the basis of animal experiments."2 In fresh water containing elevated levels of selenium, such as in the Kesterson Reservoir in California, fish may contain extremely high levels of selenium.
ESSENTIAL ELEMENT In human and animal diets selenium is known to be an essential trace element. The largest proportion of selenium in animals is found in the muscles, while the kidneys have the highest selenium concentration. The total mass of the element in a person of 70 kg is about 20 mg, with most of it in kidneys, muscle, spleen and liver, and, in the male, in the testicles. According to Mervyn, the functions of selenium are the following: preservation of normal liver and heart functions; maintaining resistance to disease; protection against toxic minerals and against toxic substances produced in body; maintaining healthy eyes and sight; maintains healthy hair and skin; act as anti-inflammatory agent; protects the body as an anti-oxidant. 3 Therapeutically selenium [as a supplementation] is used to detoxify the body of arsenic, lead, cadmium, copper, thallium, and mercury. [These metals are thought to be more toxic in the presence of selenium deficiency.] Selenium is synergistic with vitamin E; both are required to form glutathione peroxidase, an antioxidant enzyme present in liver, heart and other tissues in man and animals. If the intake of vitamin E is low, susceptibility to selenium toxicity is increased in experimental animals, whereas resistance is increased if vitamin E intake is increased. Selenium deficiency reportedly is a factor in humans in premature ageing and in susceptibility to infections. Zinc, cadmium, and copper counteract the effects of selenium in the body. "Deficiency of selenium in lambs and calves produces congenital 'white muscle disease', a form of nutritionally induced muscular dystrophy. Deficiency of selenium produces liver necrosis in rats, a bleeding disorder in poultry, and cellular necrosis in the liver, kidneys, and skeletal and heart muscles in mice, resulting in cardiac failure and death. In each of these entities the health effect is prevented by adding selenium to the diet so that now there are well-defined dietary requirements for selenium for livestock and poultry."4 Other problems possibly associated with selenium deficiency include eczema, psoriasis, rheumatoid arthritis, cataracts, cervical dysplasia, and alcoholism. Cataracts have been shown to contain only about one-sixth as much selenium as a normal lens, but it is unclear whether this is a cause or a result of the cataract. "Selenium plays an important role in the control of thyroid hormone metabolism. The iodothyronine deiodinases, which are responsible for the conversion of thyroxine [T4] to its active form, triiodothyronine [T3], are selenoenzymes. Selenium deficiency may cause reduced growth rates owing to a feedback response which lowers triiodothyronine mediated synthesis of growth hormone in the pituitary, while a combined deficiency of selenium and iodine exacerbates hypothyroidism."5 Adequate selenium levels in food are thought to protect against neurologic effects of iodine deficiency. Gastrointestinal disorders such as Crohn's disease can impair absorption of selenium [and of other nutrients as well].
FOOD Selenium is a constituent of proteins, as is sulphur. Food sources with a high selenium content include organ meats, fish and shellfish [esp. shrimps], muscle meats, wholegrains and cereals, dairy products, garlic, onions, walnuts, and Brazil nuts. Deficiencies may be induced by living on diets high in refined and processed foods. The level of selenium in grain depend on the soil where it is grown; American wheat contains more selenium than European wheat. In Finland selenium supplements are added to crop fertilisers to raise the level of the mineral in the soil and thus to increase public consumption. A study of selenium in Germany showed that the soils in Germany are very low in selenium and the largest contributions to selenium in the German diet come from beer and seafood.
SOIL Selenium is not an essential element for plants, although soluble selenium is readily absorbed by plants. Soils rich in clay content generally have also an increased selenium content. Because selenium naturally occurs in sulphur deposits and sulphide ores [of heavy metals] produced as a result of volcanic activity, soil in the neighbourhood of volcanoes tend to have enriched amounts of the element. The availability of selenium, for plants, decreases with decreasing temperature and increasing rainfall. "Irregular distribution of the mineral occurs in soils of various countries and areas within the same country. This is reflected in the selenium contents of the foods grown in those areas. Low levels [occur] in Europe; USA; Australia; New Zealand. High levels in Formosa; Japan; Thailand; Philippines; Puerto Rico; Venezuela; Costa Rica. Within the UK, Norfolk has high levels. Within the USA, Wyoming and Dakota have high levels. Epidemiological studies indicate that those who live in areas of low selenium soils have more cancer and heart complaints than those living in high selenium soils."6 A juvenile cardiomyopathy known as Keshan disease has been attributed to selenium deficiency. The disease was characterized in children between 2 and 10 by heart enlargement, heart weakness and irregular rhythm, and fluid on the lungs. Keshan disease occurs mainly during the winter season in North China and during the summer season in South China. With a mortality in the acute form of up to 50% in children, the disease had been known in China for many years before a severe outbreak occurred in 1935 in Keshan County, from which the disease took its present name. Selenium deficiency was suspected and daily intake of the element was found to be 10-20 mcg. "Beginning in 1974, a large-scale experiment to study the role of selenium in Keshan disease was made in Mianning County in south China. During a two year period, tablets containing sodium selenite were given regularly to more than 11,000 children under nine years old. A control group of more than 9,000 children received placebo tablets, containing a trace of garlic to simulate the taste of the selenium salt. The results were convincing. Among the children who took the placebo tablets, 106 developed Keshan disease and 53 died. Among those treated with selenium there were 17 cases and one death. It was then decided to give selenium supplements to all children in the county, since a control group was clearly unnecessary; by 1977 the disease had been virtually eliminated."7
CANCER Studies suggest that a substantial increase of dietary intake of selenium, to 300 mcg per day [minimum daily requirement is 60-100 mcg] would protect against cancer. Skin cancers induced by excessive ultra-violet light have been inhibited by selenium [in combination with vitamins C and E]. The possible anti-cancer effect of selenium supplements have induced in recent years great enthusiasm for these products. The results of human experiments, however, are inconclusive and even conflicting. "One much-publicized study examined the health of 1,312 volunteers residing in low-selenium areas of the United States. For four and a half years, part of the group took selenium and the other was given a placebo. Ten years later, it was found that those taking selenium had 63% fewer prostate cancers, 58% fewer colorectal cancers, and 46% fewer lung cancers than the placebo group. Set against this study is an investigation from Harvard university which measured the amount of selenium actually present in the body tissue of 1,000 women. After four years, the researchers found that women with the highest selenium intakes showed no fewer cancers than women with the lowest intakes. In fact, the small number who took selenium supplements were almost twice as likely to get cancer, though it was not clear whether selenium was to blame. Yet another study of more than 62,000 nurses has also found no connection between the development of cancer and high - or low - levels of selenium in the body. And while many people assume that selenium's anti-cancer effects - if indeed they exist - are due to its antioxidant qualities, this is by no means certain. In fact, it is possible that cancer cells may be more susceptible to selenium poisoning than other cells. 'Cancer cells are more sensitive to selenium-induced programmed cell death,' explains Clement Ip, a selenium expert at Roswell Park Memorial Cancer Center in New York. 'So it's possible that selenium eliminates early precancerous lesions.'"8 The Cancer Research Campaign [UK] has launched in 1999 a study to examine the benefits of selenium. The study leads on to larger trials involving five different countries and some 40,000 volunteers. Comprising a two-year pilot study and a five-year main study, the results of the trial are expected in 2007. The CRC study will be led by Dr. Margaret Rayman who, in an editorial in the February 1997 issue of the British Medical Journal, sees low selenium levels in blood associated with infertility, cancer and heart disease. According to her this can be explained by reference to the drastic fall in the public's intake of this trace element. In England alone the average selenium intake has declined by half in the course of the past 22 years.
FERTILITY Selenium promotes male sexual reproductive capacity in production of prostaglandins. Men have a greater need for selenium because it functions in sperm production and motility. The element is lost in ejaculated semen. Selenium is synergistic with vitamin E. Vitamin E comprises a group of fat-soluble substances called tocopherols, a name derived from two Greek words meaning 'bearing offspring' because deficiency causes sterility. Vitamin E has been dubbed the 'fertility vitamin'. In a double-blind, placebo-controlled Scottish study [MacPherson] selenium supplementation proved to increase infertile men's sperm quality. Sperm motility improved from 17.5% to 35.1% in subfertile men supplemented with selenium in a controlled double blind trial. "Selenium is important for proper reproductive performance. Sperm capsule selenoprotein is a structural selenoprotein found in the midpiece region of the sperm tail. In selenium deficiency, morphological anomalies in this region give rise to spermatozoa with impaired motility. Selenium is also needed for normal testosterone metabolism and testicular morphology, which may explain the presence of several other selenoproteins in the male gonads."9
AGE The 'anti-ageing' effect of selenium, along with vitamin E, has been ascribed to the antioxidant functions of both elements. Selenium absorption may be reduced with ageing; in addition, older people often consume less selenium-containing fresh and whole foods. Premature old age is given as a homoeopathic indication for Selenium. Boericke says it is "often indicated in elderly men, esp. for prostatitis and sexual atony" and gives as another age-related symptom, "Easy exhaustion, mental and physical, in old age." A somewhat far-fetched, yet interesting, connection may be observed with the romantic legend of the relationship of Moon-goddess Selene and Endymion, king of Elis. Selene fell in love with Endymion because of his extraordinary beauty. According to one version of the legend, the prospect of losing his beauty with age made Endymion turn to Zeus for help. Zeus granted his request and allowed Endymion to sleep forever, remaining always young. Another version has it that Selene put Endymion to his timeless beauty sleep since she loved so much to gaze upon his attractive face. Either way, every night Selene would visit him in the cave on Mount Latmus where he slept, to just look at him or else to awaken him to fulfil her desires. Yet another legend explains the monthly disappearance of the moon as a visit of Selene to her lover Endymion, which became a literary commonplace as 'the moon sleeps with Endymion'. Nothing seemed to have been wrong with Endymion's fertility, however, for Pausanias states that the couple had fifty daughters.
PROVINGS •• [1] Hering - no information as to number of provers, potencies, or doses.
•• [2] Schreter - self-experimentations; the first with two drops of 4th dil. [effects observed for 4 days], the second with one drop of 3rd dil. [effects observed for 15 days].
•• [3] Raeside - 21 provers [13 males, 8 females], 1959-60; method: double blind, placebo-controlled; first term: 6c, one powder daily for about one month; second term: 30c, one powder daily for about one month; third term: 12c, one dose twice daily, "which seemed to produce more symptoms more violently."
"Each term we changed the provers and controls so that we had, in point of fact, 43 separate 'proving terms' and 11 'control terms'."10
All provings were conducted with the amorphous [red] modification. Because the amorphous form of the element strongly resembles sulphur in its actions, Leeser considers it "important to subject the so sensitive metallic modification [which possess the photoelectric properties] to a special proving if one would approach the selenium characteristics more closely."11
[1] Encyclopaedia Britannica. [2] Klaassen, Casarett and Doull's Toxicology. [3] Mervyn, Vitamins and Minerals. [4] Klaassen, ibid. [5] Rayman, Dietary selenium: time to act; Br. Med. Jrnl 1997, 314:387. [6] Mervyn, ibid. [7] Lenihan, The Crumbs of Creation. [8] Cox and Brusseau, Secret Ingredients. [9] Rayman, ibid. [10] Raeside, Report on a Proving of Selenium; BHJ, October 1961. [11] Leeser, Textbook of Hom. MM: Inorganic Medicinal Substances.
Affinity
Nerves [GENITO-URINARY ORGANS; supra-orbital - left]. LARYNX. Liver. * LEFT SIDE.
Modalities
Worse: Debilitating causes [hot days; sexual excesses; loss of sleep]. Singing. Drafts. After sleep. Tea. Lemonade. Sun; summer. Wine. Exertion; mental; physical. ALCOHOL. Coffee. Touch. Pressure. After stool. Talking; while and after. Walking in the open air. Every afternoon.
Better: After sunset. Inhaling cool air. Taking cold water in the mouth. Rest.
Main symptoms
M Prostration of mind, difficult concentration.
• "Complete inability to do any work; though he always begins again he must soon leave off. After mental work continued zealously till late at night he is so uncommonly fatigued that for several days he can only think of the most necessary things, and it is only after a long time that he can go on with his work. Dislike to persons and to his work, but when he overcomes this he can go on all right." [H]
Great forgetfulness.
Forgotten things come to mind in sleep [when lying half asleep].
• "Very forgetful, esp. in business matters, but when he is half asleep he remembers everything." [H]
Depression and tiredness.
• "Its effects on the mind was mainly one of tiredness, with lack of enthusiasm. Thus depression was often accompanied by tiredness, or a drowsy feeling. They described themselves as detached, forgetful, can't be bothered doing anything. ... Depression and tiredness, feels that nothing is worth while. Everything seems pointless." [R]
M Theorizing; religious reveries.
G LASSITUDE and weakness.
Especially if caused by prolonged FEVER, seminal discharges, loss of sleep or abuse of ALCOHOL.
G CHILLY.
G c Oversensitive to DRAFTS.
[= headache, pain in limbs]
Sensitiveness so great that he "imagines drafts of air."
c Oversensitive to HOT weather.
[= weakness].
• "The hotter the body is, the weaker he is. Strength rises as sun sinks; loquacity, fond of conserving in evening." [Clarke]
• "He must lie down as long as the heat of day lasts, and he remains half asleep; his thinking power is quite weak." [H]
G Craving for alcohol [= stimulating].
• "Late in evening he has great inclination to drink brandy, though quite unused to it. Frequent longing for brandy." [H]
Especially before menses [on account of weakness].
G SALT [aversion + <.]. G Strong sexual desire and impotency. G < During and after coition. < Emissions. G < After sleep, mainly on warm days. G < AFTER eating [inclination to lie down; pulsation externally]. G Ailments after SUPPRESSED ERUPTIONS [esp. with sulphur-ointments]. G LOSS of HAIR of the whole body. [head, eyebrows, whiskers, pubic hair] G PULSATION in all parts of body. Especially abdomen, after eating; prevents sleep. G EMACIATION ofOpen air.
• "In the head there was a characteristic headache which was frontal, throbbing or pressing, over the eyes esp. right and extending back to the occiput." [R]
P Pain in the HAIR when TOUCHED.
Don't want the hair touched. [Boger]
P Vision.
• "Difficulty focusing the eyes, with vertigo, < movement of head or body." [R] • "Vision blurred, objects seem to move when looked at." [R] P Skin of face greasy. Acne and comedones. Seborrhoea. P Constipation after exhausting diseases. P Male sexual system. • "Even more definite than with Sulphur are the states of weakness in the male sexual system. It is this indication which usually leads to the choice of Selenium. In fantasy there exists a sexual irritability, but still there is a physical impotency: frequent involuntary seminal emissions without erections; or slow and weak erections; ejaculatio praecox; also prostatorrhoea. Frequently observed is an unpleasant sensation of drops which roll along the urethra, due to a prostatorrhoea but also to an after-dropping of urine or to an inflammatory state of the urethra as in chronic gonorrhoea. This dropping sensation is observed particularly on walking and after evacuation of the bladder or bowel. The nocturnal polyuria which is important for Sulphur should also be noted here. Residual states of chronic gonorrhoea to which are joined neurasthenic symptoms are given as indications for Selenium." [Leeser] P Nails brittle, [longitudinally] ridged, and tending to inflammation. [toxicological] [H] = proving Hering. [R] = proving Raeside. Rubrics Mind Aversion to certain persons [1]. Aversion to company of intimate friends [2]. Confusion, after coition [1]. Repulsive fancies when alone [1]. Fear, in a crowd [1], of work [1]. Indifference to everything [1]. Libertinism [1]. Loquacity in evening [1]. Prostration of mind after prolonged fever [1/1]. Sexual thoughts intrude and crowd around each other [1]. Bashful timidity [1]. Vertigo On motion of head [1]; motion = vomiting and nausea [1]. Head Pain, from acids [2], from strong odours [1], from exposure to sun [2]. Vision Objects seem to be moving when looking at them [1R]. Ear Blowing sensation in ears during headache [2/1]. Nose Smell acute, sensitive to odour of flowers [roses, musk] [1C]. Stomach Appetite increased during headache [1]. Vomiting, of bile, after tea [1/1]. Larynx Voice, hoarseness when beginning to talk [1/1]. Chest Pain, dull or stitching, region of heart, < moving arms [1R]. Back Pain, coccyx, < sitting [1R], < walking [1R]. Limbs Itching bends of joints [1]. Pain, from draft of air, even warm [2/1]. Sleep Interrupted during hot weather [1/1]. Perspiration Salty deposits after perspiration [1/1]. Skin Sensation as from electric sparks [2]. Generals Weakness, from heat [3], from summer heat [3]. * Repertory additions: [C] = Clarke; [R] = Raeside. Food Aversion: [2]: Salt; tea. [1]: Meat. Desire: [2]: Alcohol; brandy; coffee; whisky. [1]: Meat; refreshing things; salt; tea; wine. Worse: [3]: Tea. [2]: Fruit; lemonade; salt; wine. [1]: Meat; sour; spicy; sweets. Better: [1]: Cold food; cold water; wine.
Memory is a net; one finds it full of fish when he takes it from the brook, but a dozen miles of water have run through it without sticking.
[Oliver Wendell Holmes, Sr.]
Signs
Selenium.
CLASSIFICATION Selenium is a metalloid element in group 16 of the periodic table, along with the lighter elements oxygen and sulphur, and the heavier tellurium and polonium. It was discovered in 1817 by the Swedish chemist Berzelius. He named it after selene, the moon, because he found it associated with tellurium, an element named for the earth [tellus = earth]. [An element discovered in the 13th century and described by an Italian scholar as 'red sulphur' is now supposed to have been amorphous selenium.] As a metalloid it stands between metals and non-metals, that is, it has properties of both but equals neither of them. Selenium occasionally occurs uncombined, usually in conjunction with free sulphur; it is more commonly found together with the sulphides as the selenides in ores of such metals as iron, lead, silver, and copper. It is found in small quantities in a few rare minerals, such as clausthalite [with lead], naumannite [with lead and silver], crooksite [with copper and thallium] and tiemannite [with mercury]. In commerce, the element is obtained from the slimes and sludges formed in producing sulphuric acid, and from the anode muds from electrolytic copper, nickel, or silver refineries. Other sources are the flue dusts remaining from processing copper sulphide ores or from lead production, and the gases formed in roasting pyrites [iron disulphides]. The mineral called selenite is in fact a variety of gypsum [calcium sulphate] with broad transparent crystals; it got its name because the ancients believed it to wax and wane with the moon.
FEATURES Selenium exists in three main forms: amorphous, crystalline, and metallic. These forms have two colour varieties: red and greyish black. It is red in the powdered amorphous form and ruby red in the crystalline form; in its glassy amorphous form and when metallic it is black or greyish, respectively. Brought to its boiling point the element forms dark red vapours; liquid selenium is a brownish red. The element resembles sulphur both in its various forms and in its compounds. The metallic form is the most stable under ordinary conditions, whereas the other forms very slowly convert to the metallic form at room temperature. Due to its affinity for hydrogenium, with which it combines directly, selenium manifests a distinct tendency to form acids in the higher valences, of which selenic acid is as strong as sulphuric acid. It combines directly with the halogens, excluding iodine, and reacts with many metals. Selenium burns in air with a bright blue flame forming the dioxide and emitting a characteristic odour resembling rotten horseradish. [Group 16 comprises malodorous elements: oxygen has a pungent smell in its triatomic form as ozone; burnt sulphur gives off a pungent odour; burnt selenium smells of rotten horseradish; tellurium emits a garlicky odour; polonium is a product of the decay of radium. The members of neighbouring group 15 are no less smelly. Itself an odourless gas, nitrogen is essential for the formation of ammonia; phosphorus and arsenic smell of garlic; the heaviest members, antimony and bismuth, are relatively odourless. With the exception of the inert nitrogen, all members of both groups share the property of allotropy: they exist in more than one form.] Vitreous or glassy selenium is formed by rapid cooling of the molten element; it softens at 50-60o C and becomes elastic at 70o C. The other amorphous form, consisting of red powder, is formed by condensation of selenium vapour on a cold surface.
PROPERTIES Selenium's most remarkable properties are related to light and electricity. The element, in its metallic form, is able to convert light directly into electricity. It also changes one type of electricity [alternating current] into another [direct current]. In addition, it exhibits photoconductive action: increased illumination decreases its electrical resistance more than 1,000-fold. These properties makes selenium useful in the production of photoelectric cells, solar cells, and exposure meters for photographic use. "The electrical resistivity of selenium varies over a tremendous range, depending upon such variables as the nature of the allotrope, impurities, the method of refining, temperature, and pressure. Most metals are insoluble in selenium, and non-metallic impurities increase the resistivity. Illumination of crystalline selenium for 0.001 second increases its conductivity by a factor of 10 to 15 times. Red light is more effective than light of shorter wave length."1
USES As photoelectric cells, solar cells, and photographic exposure meters the photoconductive and photosensitive properties of selenium are utilized in devices that translate variations in light intensity into electric current and thence to visual, magnetic, or mechanical effects. Alarm devices, mechanical opening and closing devices, safety systems, counting devices, electronic control systems in factory assembly lines, industrial colour perceptors, television, sound films and xerography depend upon such properties. In devices as dynamos and all sorts of generators the element is used for electric power generation. The glass industry is another user of selenium. Added in small amounts to glass, selenium serves as a decolourizer by eliminating the green tinge produced by traces of iron; incorporated in larger amounts it is used to make glass of a clear red colour such as in signal lamps and traffic lights. The dark ['black'] glass used in windows or walls of buildings, to reduce glare and transmission of solar heat, also contains selenium compounds. The element is also employed in the manufacture of red enamels for ceramics and steel ware, and of pigments for plastics, pains, inks and rubber, as well as for the vulcanization of rubber to increase resistance to abrasion. Selenium sulphide is used in shampoos for the treatment of dandruff and seborrhoeic dermatitis of the scalp; the compound is highly toxic if taken internally.
TOXICOLOGY Toxic intake of selenium is believed to be 10-35 mg, although some authorities mention amounts as low as 5 mg. These differences may be explained by the fact that the toxic potential for selenium and selenium compounds is related to their chemical form and to solubility. Selenates [salts of selenic acid; selenium in valency 6] are relatively soluble compounds, similar to sulphates, and are readily taken up by biological systems. Selenites [salts of selenious acid; selenium in valency 4] and elemental selenium are virtually insoluble and are regarded to be inert. Selenium is thought to interfere with sulphur compounds and even replace the sulphur in the body, as these two minerals are very similar biochemically, and thus may decrease a number of enzyme actions. Some compounds, e.g. hydrogen selenide, are extremely toxic and resemble arsenic in their physiological reactions. Hydrogen selenide - a foul-smelling gas - is a cumulative poison and in a concentration of 1.5 ppm is intolerable to man. Grasses, grains and most weeds do not accumulate selenium even when grown in high-selenium areas, but certain other plants are able to absorb and accumulate selenium compounds in sufficient quantities to make them poisonous to animals. These plants include species of Aster, numerous species of Astragalus [locoweed or milk vetch], species of Atriplex [orach or salt bush], and Grindelia squarrosa, amongst others. 'Blind staggers' is one type of disease in cattle, sheep, and horses attributed to selenium poisoning. The disease is characterized by impairment of vision, dulness, loss of muscular control, irregularity in gait and eating, tendency to wander in circles, and loss of flesh. The animal becomes solitary in habit and eventually ceases to eat and dies [from respiratory failure]. A more chronic syndrome, known as 'alkali disease', has been described in livestock and horses. It is characterized by loss of vitality, emaciation, deformity and shedding of hoofs, loss of long hair, and erosion of joints of long bones. Similar syndromes appear in sheep and dogs. In humans, symptoms of excess intake include dental caries, lassitude, depression, irritability, pallor, skin depigmentation, and a garlic odour to the breath. Klaassen refers to a study of 70 families "living in three counties of South Dakota and in one county of northern Nebraska, from farms where alkali disease in cattle had been recognized, found bad teeth, a yellowish discolouration of the skin, skin eruptions, and diseased nails of the fingers and toes in various family members. A syndrome now believed to be the result of selenium intoxication was discovered in 1961 to affect about 50% of 248 inhabitants of five villages in the Hubei province of China. There are similarities between this syndrome and the chronic effects in livestock and horses. The main symptoms were brittle hair with intact follicles, brittle nails with spots and streaks, and skin lesions on the back of hands and feet and on the forearms, legs, and the back of the neck. These areas were red and swollen, and contained blisters. In addition, 13 of 22 people in one village had neurological symptoms including peripheral anaesthesia, pain, and hyperreflexia. In some individuals these symptoms progressed to numbness, convulsions, paralysis, and altered motor function Selenium has produced loss of fertility and congenital defects and is considered embryotoxic and teratogenic on the basis of animal experiments."2 In fresh water containing elevated levels of selenium, such as in the Kesterson Reservoir in California, fish may contain extremely high levels of selenium.
ESSENTIAL ELEMENT In human and animal diets selenium is known to be an essential trace element. The largest proportion of selenium in animals is found in the muscles, while the kidneys have the highest selenium concentration. The total mass of the element in a person of 70 kg is about 20 mg, with most of it in kidneys, muscle, spleen and liver, and, in the male, in the testicles. According to Mervyn, the functions of selenium are the following: preservation of normal liver and heart functions; maintaining resistance to disease; protection against toxic minerals and against toxic substances produced in body; maintaining healthy eyes and sight; maintains healthy hair and skin; act as anti-inflammatory agent; protects the body as an anti-oxidant. 3 Therapeutically selenium [as a supplementation] is used to detoxify the body of arsenic, lead, cadmium, copper, thallium, and mercury. [These metals are thought to be more toxic in the presence of selenium deficiency.] Selenium is synergistic with vitamin E; both are required to form glutathione peroxidase, an antioxidant enzyme present in liver, heart and other tissues in man and animals. If the intake of vitamin E is low, susceptibility to selenium toxicity is increased in experimental animals, whereas resistance is increased if vitamin E intake is increased. Selenium deficiency reportedly is a factor in humans in premature ageing and in susceptibility to infections. Zinc, cadmium, and copper counteract the effects of selenium in the body. "Deficiency of selenium in lambs and calves produces congenital 'white muscle disease', a form of nutritionally induced muscular dystrophy. Deficiency of selenium produces liver necrosis in rats, a bleeding disorder in poultry, and cellular necrosis in the liver, kidneys, and skeletal and heart muscles in mice, resulting in cardiac failure and death. In each of these entities the health effect is prevented by adding selenium to the diet so that now there are well-defined dietary requirements for selenium for livestock and poultry."4 Other problems possibly associated with selenium deficiency include eczema, psoriasis, rheumatoid arthritis, cataracts, cervical dysplasia, and alcoholism. Cataracts have been shown to contain only about one-sixth as much selenium as a normal lens, but it is unclear whether this is a cause or a result of the cataract. "Selenium plays an important role in the control of thyroid hormone metabolism. The iodothyronine deiodinases, which are responsible for the conversion of thyroxine [T4] to its active form, triiodothyronine [T3], are selenoenzymes. Selenium deficiency may cause reduced growth rates owing to a feedback response which lowers triiodothyronine mediated synthesis of growth hormone in the pituitary, while a combined deficiency of selenium and iodine exacerbates hypothyroidism."5 Adequate selenium levels in food are thought to protect against neurologic effects of iodine deficiency. Gastrointestinal disorders such as Crohn's disease can impair absorption of selenium [and of other nutrients as well].
FOOD Selenium is a constituent of proteins, as is sulphur. Food sources with a high selenium content include organ meats, fish and shellfish [esp. shrimps], muscle meats, wholegrains and cereals, dairy products, garlic, onions, walnuts, and Brazil nuts. Deficiencies may be induced by living on diets high in refined and processed foods. The level of selenium in grain depend on the soil where it is grown; American wheat contains more selenium than European wheat. In Finland selenium supplements are added to crop fertilisers to raise the level of the mineral in the soil and thus to increase public consumption. A study of selenium in Germany showed that the soils in Germany are very low in selenium and the largest contributions to selenium in the German diet come from beer and seafood.
SOIL Selenium is not an essential element for plants, although soluble selenium is readily absorbed by plants. Soils rich in clay content generally have also an increased selenium content. Because selenium naturally occurs in sulphur deposits and sulphide ores [of heavy metals] produced as a result of volcanic activity, soil in the neighbourhood of volcanoes tend to have enriched amounts of the element. The availability of selenium, for plants, decreases with decreasing temperature and increasing rainfall. "Irregular distribution of the mineral occurs in soils of various countries and areas within the same country. This is reflected in the selenium contents of the foods grown in those areas. Low levels [occur] in Europe; USA; Australia; New Zealand. High levels in Formosa; Japan; Thailand; Philippines; Puerto Rico; Venezuela; Costa Rica. Within the UK, Norfolk has high levels. Within the USA, Wyoming and Dakota have high levels. Epidemiological studies indicate that those who live in areas of low selenium soils have more cancer and heart complaints than those living in high selenium soils."6 A juvenile cardiomyopathy known as Keshan disease has been attributed to selenium deficiency. The disease was characterized in children between 2 and 10 by heart enlargement, heart weakness and irregular rhythm, and fluid on the lungs. Keshan disease occurs mainly during the winter season in North China and during the summer season in South China. With a mortality in the acute form of up to 50% in children, the disease had been known in China for many years before a severe outbreak occurred in 1935 in Keshan County, from which the disease took its present name. Selenium deficiency was suspected and daily intake of the element was found to be 10-20 mcg. "Beginning in 1974, a large-scale experiment to study the role of selenium in Keshan disease was made in Mianning County in south China. During a two year period, tablets containing sodium selenite were given regularly to more than 11,000 children under nine years old. A control group of more than 9,000 children received placebo tablets, containing a trace of garlic to simulate the taste of the selenium salt. The results were convincing. Among the children who took the placebo tablets, 106 developed Keshan disease and 53 died. Among those treated with selenium there were 17 cases and one death. It was then decided to give selenium supplements to all children in the county, since a control group was clearly unnecessary; by 1977 the disease had been virtually eliminated."7
CANCER Studies suggest that a substantial increase of dietary intake of selenium, to 300 mcg per day [minimum daily requirement is 60-100 mcg] would protect against cancer. Skin cancers induced by excessive ultra-violet light have been inhibited by selenium [in combination with vitamins C and E]. The possible anti-cancer effect of selenium supplements have induced in recent years great enthusiasm for these products. The results of human experiments, however, are inconclusive and even conflicting. "One much-publicized study examined the health of 1,312 volunteers residing in low-selenium areas of the United States. For four and a half years, part of the group took selenium and the other was given a placebo. Ten years later, it was found that those taking selenium had 63% fewer prostate cancers, 58% fewer colorectal cancers, and 46% fewer lung cancers than the placebo group. Set against this study is an investigation from Harvard university which measured the amount of selenium actually present in the body tissue of 1,000 women. After four years, the researchers found that women with the highest selenium intakes showed no fewer cancers than women with the lowest intakes. In fact, the small number who took selenium supplements were almost twice as likely to get cancer, though it was not clear whether selenium was to blame. Yet another study of more than 62,000 nurses has also found no connection between the development of cancer and high - or low - levels of selenium in the body. And while many people assume that selenium's anti-cancer effects - if indeed they exist - are due to its antioxidant qualities, this is by no means certain. In fact, it is possible that cancer cells may be more susceptible to selenium poisoning than other cells. 'Cancer cells are more sensitive to selenium-induced programmed cell death,' explains Clement Ip, a selenium expert at Roswell Park Memorial Cancer Center in New York. 'So it's possible that selenium eliminates early precancerous lesions.'"8 The Cancer Research Campaign [UK] has launched in 1999 a study to examine the benefits of selenium. The study leads on to larger trials involving five different countries and some 40,000 volunteers. Comprising a two-year pilot study and a five-year main study, the results of the trial are expected in 2007. The CRC study will be led by Dr. Margaret Rayman who, in an editorial in the February 1997 issue of the British Medical Journal, sees low selenium levels in blood associated with infertility, cancer and heart disease. According to her this can be explained by reference to the drastic fall in the public's intake of this trace element. In England alone the average selenium intake has declined by half in the course of the past 22 years.
FERTILITY Selenium promotes male sexual reproductive capacity in production of prostaglandins. Men have a greater need for selenium because it functions in sperm production and motility. The element is lost in ejaculated semen. Selenium is synergistic with vitamin E. Vitamin E comprises a group of fat-soluble substances called tocopherols, a name derived from two Greek words meaning 'bearing offspring' because deficiency causes sterility. Vitamin E has been dubbed the 'fertility vitamin'. In a double-blind, placebo-controlled Scottish study [MacPherson] selenium supplementation proved to increase infertile men's sperm quality. Sperm motility improved from 17.5% to 35.1% in subfertile men supplemented with selenium in a controlled double blind trial. "Selenium is important for proper reproductive performance. Sperm capsule selenoprotein is a structural selenoprotein found in the midpiece region of the sperm tail. In selenium deficiency, morphological anomalies in this region give rise to spermatozoa with impaired motility. Selenium is also needed for normal testosterone metabolism and testicular morphology, which may explain the presence of several other selenoproteins in the male gonads."9
AGE The 'anti-ageing' effect of selenium, along with vitamin E, has been ascribed to the antioxidant functions of both elements. Selenium absorption may be reduced with ageing; in addition, older people often consume less selenium-containing fresh and whole foods. Premature old age is given as a homoeopathic indication for Selenium. Boericke says it is "often indicated in elderly men, esp. for prostatitis and sexual atony" and gives as another age-related symptom, "Easy exhaustion, mental and physical, in old age." A somewhat far-fetched, yet interesting, connection may be observed with the romantic legend of the relationship of Moon-goddess Selene and Endymion, king of Elis. Selene fell in love with Endymion because of his extraordinary beauty. According to one version of the legend, the prospect of losing his beauty with age made Endymion turn to Zeus for help. Zeus granted his request and allowed Endymion to sleep forever, remaining always young. Another version has it that Selene put Endymion to his timeless beauty sleep since she loved so much to gaze upon his attractive face. Either way, every night Selene would visit him in the cave on Mount Latmus where he slept, to just look at him or else to awaken him to fulfil her desires. Yet another legend explains the monthly disappearance of the moon as a visit of Selene to her lover Endymion, which became a literary commonplace as 'the moon sleeps with Endymion'. Nothing seemed to have been wrong with Endymion's fertility, however, for Pausanias states that the couple had fifty daughters.
PROVINGS •• [1] Hering - no information as to number of provers, potencies, or doses.
•• [2] Schreter - self-experimentations; the first with two drops of 4th dil. [effects observed for 4 days], the second with one drop of 3rd dil. [effects observed for 15 days].
•• [3] Raeside - 21 provers [13 males, 8 females], 1959-60; method: double blind, placebo-controlled; first term: 6c, one powder daily for about one month; second term: 30c, one powder daily for about one month; third term: 12c, one dose twice daily, "which seemed to produce more symptoms more violently."
"Each term we changed the provers and controls so that we had, in point of fact, 43 separate 'proving terms' and 11 'control terms'."10
All provings were conducted with the amorphous [red] modification. Because the amorphous form of the element strongly resembles sulphur in its actions, Leeser considers it "important to subject the so sensitive metallic modification [which possess the photoelectric properties] to a special proving if one would approach the selenium characteristics more closely."11
[1] Encyclopaedia Britannica. [2] Klaassen, Casarett and Doull's Toxicology. [3] Mervyn, Vitamins and Minerals. [4] Klaassen, ibid. [5] Rayman, Dietary selenium: time to act; Br. Med. Jrnl 1997, 314:387. [6] Mervyn, ibid. [7] Lenihan, The Crumbs of Creation. [8] Cox and Brusseau, Secret Ingredients. [9] Rayman, ibid. [10] Raeside, Report on a Proving of Selenium; BHJ, October 1961. [11] Leeser, Textbook of Hom. MM: Inorganic Medicinal Substances.
Affinity
Nerves [GENITO-URINARY ORGANS; supra-orbital - left]. LARYNX. Liver. * LEFT SIDE.
Modalities
Worse: Debilitating causes [hot days; sexual excesses; loss of sleep]. Singing. Drafts. After sleep. Tea. Lemonade. Sun; summer. Wine. Exertion; mental; physical. ALCOHOL. Coffee. Touch. Pressure. After stool. Talking; while and after. Walking in the open air. Every afternoon.
Better: After sunset. Inhaling cool air. Taking cold water in the mouth. Rest.
Main symptoms
M Prostration of mind, difficult concentration.
• "Complete inability to do any work; though he always begins again he must soon leave off. After mental work continued zealously till late at night he is so uncommonly fatigued that for several days he can only think of the most necessary things, and it is only after a long time that he can go on with his work. Dislike to persons and to his work, but when he overcomes this he can go on all right." [H]
Great forgetfulness.
Forgotten things come to mind in sleep [when lying half asleep].
• "Very forgetful, esp. in business matters, but when he is half asleep he remembers everything." [H]
Depression and tiredness.
• "Its effects on the mind was mainly one of tiredness, with lack of enthusiasm. Thus depression was often accompanied by tiredness, or a drowsy feeling. They described themselves as detached, forgetful, can't be bothered doing anything. ... Depression and tiredness, feels that nothing is worth while. Everything seems pointless." [R]
M Theorizing; religious reveries.
G LASSITUDE and weakness.
Especially if caused by prolonged FEVER, seminal discharges, loss of sleep or abuse of ALCOHOL.
G CHILLY.
G c Oversensitive to DRAFTS.
[= headache, pain in limbs]
Sensitiveness so great that he "imagines drafts of air."
c Oversensitive to HOT weather.
[= weakness].
• "The hotter the body is, the weaker he is. Strength rises as sun sinks; loquacity, fond of conserving in evening." [Clarke]
• "He must lie down as long as the heat of day lasts, and he remains half asleep; his thinking power is quite weak." [H]
G Craving for alcohol [= stimulating].
• "Late in evening he has great inclination to drink brandy, though quite unused to it. Frequent longing for brandy." [H]
Especially before menses [on account of weakness].
G SALT [aversion + <.]. G Strong sexual desire and impotency. G < During and after coition. < Emissions. G < After sleep, mainly on warm days. G < AFTER eating [inclination to lie down; pulsation externally]. G Ailments after SUPPRESSED ERUPTIONS [esp. with sulphur-ointments]. G LOSS of HAIR of the whole body. [head, eyebrows, whiskers, pubic hair] G PULSATION in all parts of body. Especially abdomen, after eating; prevents sleep. G EMACIATION of
• "In the head there was a characteristic headache which was frontal, throbbing or pressing, over the eyes esp. right and extending back to the occiput." [R]
P Pain in the HAIR when TOUCHED.
Don't want the hair touched. [Boger]
P Vision.
• "Difficulty focusing the eyes, with vertigo, < movement of head or body." [R] • "Vision blurred, objects seem to move when looked at." [R] P Skin of face greasy. Acne and comedones. Seborrhoea. P Constipation after exhausting diseases. P Male sexual system. • "Even more definite than with Sulphur are the states of weakness in the male sexual system. It is this indication which usually leads to the choice of Selenium. In fantasy there exists a sexual irritability, but still there is a physical impotency: frequent involuntary seminal emissions without erections; or slow and weak erections; ejaculatio praecox; also prostatorrhoea. Frequently observed is an unpleasant sensation of drops which roll along the urethra, due to a prostatorrhoea but also to an after-dropping of urine or to an inflammatory state of the urethra as in chronic gonorrhoea. This dropping sensation is observed particularly on walking and after evacuation of the bladder or bowel. The nocturnal polyuria which is important for Sulphur should also be noted here. Residual states of chronic gonorrhoea to which are joined neurasthenic symptoms are given as indications for Selenium." [Leeser] P Nails brittle, [longitudinally] ridged, and tending to inflammation. [toxicological] [H] = proving Hering. [R] = proving Raeside. Rubrics Mind Aversion to certain persons [1]. Aversion to company of intimate friends [2]. Confusion, after coition [1]. Repulsive fancies when alone [1]. Fear, in a crowd [1], of work [1]. Indifference to everything [1]. Libertinism [1]. Loquacity in evening [1]. Prostration of mind after prolonged fever [1/1]. Sexual thoughts intrude and crowd around each other [1]. Bashful timidity [1]. Vertigo On motion of head [1]; motion = vomiting and nausea [1]. Head Pain, from acids [2], from strong odours [1], from exposure to sun [2]. Vision Objects seem to be moving when looking at them [1R]. Ear Blowing sensation in ears during headache [2/1]. Nose Smell acute, sensitive to odour of flowers [roses, musk] [1C]. Stomach Appetite increased during headache [1]. Vomiting, of bile, after tea [1/1]. Larynx Voice, hoarseness when beginning to talk [1/1]. Chest Pain, dull or stitching, region of heart, < moving arms [1R]. Back Pain, coccyx, < sitting [1R], < walking [1R]. Limbs Itching bends of joints [1]. Pain, from draft of air, even warm [2/1]. Sleep Interrupted during hot weather [1/1]. Perspiration Salty deposits after perspiration [1/1]. Skin Sensation as from electric sparks [2]. Generals Weakness, from heat [3], from summer heat [3]. * Repertory additions: [C] = Clarke; [R] = Raeside. Food Aversion: [2]: Salt; tea. [1]: Meat. Desire: [2]: Alcohol; brandy; coffee; whisky. [1]: Meat; refreshing things; salt; tea; wine. Worse: [3]: Tea. [2]: Fruit; lemonade; salt; wine. [1]: Meat; sour; spicy; sweets. Better: [1]: Cold food; cold water; wine.
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