Introduction to 'Rasashaastra' the Iatrochemistry of Ayurveda.

The word Rasashaastra literally means the "Science of Mercury". It is a specialized branch of Ayurveda dealing mainly with materials which are known as 'Rasa dravyaas'. The products dealt under this discipline are an important component of Ayurvedic therapeutics. Considering the importance of this discipline in Ayurvedic therapeutics and the fact that there is dearth of comprehensive review on the subject an attempt has been made in this review to provide a brief but all encompassing coverage of different aspects related to it. The subjects covered in the review are: historical background of the evolvement of Rasashaastra as a specialized branch during different time periods; different aspects of classification 'Rasa dravyaas'; processing of metal and mineral products with a note on the methods used during different time periods; information about methods of pre and post preparation procedures for different kinds of 'Rasa dravyaas'; importance of mercury in Ayurveda, its processing methods and different preparations along with therapeutic indications. In addition attempt has been made to provide basic information on the metal and mineral based preparations mentioned in Ayurvedic Formulary of India; recent development in the field of Rasashaastra and future requirements for the proper development of the discipline. The main focus is to familiarize the readers, from non-ayurvedic background, on different aspects of this specialized discipline.

[Mercury--a major agent in the history of medicine and alchemy]. / Kviksølv--et centralt stof i medicinens og alkymiens historie.

From ancient time the history of mercury has been connected with that of the medicine and chemistry. Mercury therefore contributes to the history of science throughout times. Knowledge of cinnabar (HgS) is traced back to ancient Assyria and Egypt, but also to China. The Greek philosophers were the initiators of theoretical science. The idea of the four elements, earth, air, water and fire, was introduced mainly by Empedocles and Aristotle in the 5th and 4th century BC. The theory encouraged the hope of transmuting metal to gold. The early development of practical alchemy is obscure, but some hints are given in the encyclopedia compiled by Zosimos about 300 A.D. in Alexandria. It also includes the invention of equipment such as stills, furnaces and heating baths. Medical treatment is described by Pliny and Celsus, e.g. the use of cinnabar in trachoma and venereal diseases. When the Arabs learned Greek alchemy by the Nestorians, they introduced or improved chemical equipments and new chemicals were obtained such as sublimate (HgCl2), different salts, acids, alkaline carbonates and metal oxides. The first recorded account of animal experimentation on the toxicity of mercury comes from Rhazes (al-Razi) in the 9th century and in the 11th century Avicenna (Ibn Sina) had the foresight to recommend the use of mercury only as an external remedy, and quicksilver ointments were used by the Arabs in the treating of skin diseases. In the medieval west scientific experiments were forbidden since the interpretation of the world order should not be changed. Greek and Arabic medicine and alchemy were therefore authoritative and the breakthrough in scientific inventions first appeared after the introduction of the Renaissance. The Renaissance medicine included ancient medicine as well as "modern medicine", based on iatrochemistry, and this chemical approach was introduced by Paracelsus. The medicine included sulphur and salts or oxides of for instance mercury, copper, iron, antimony, bismuth and lead. Most important was mercury when the outbreak of syphilis appeared in Europe at the end of the 15th century. The Arabian quicksilver ointment was remembered and used for the treatment of syphilis, but the treatment also included pills and ointments of sublimate and calomel (Hg2Cl2). The breakthrough in science was the discovery of oxygen by Priestley in the late 18th century. Priestley heated the oxide of mercury and examined the gas and thereafter Lavoisier recognized that combustion involves oxidation. All this led to a new understanding of respiration and furthermore established the basis of modern chemistry. The apothecaries of the 19th and 20th century showed many colourful mercurials as calomel, sublimate, cinnober, oxides of mercury and mercury. Calomel pills were used in acute and chronic diseases and furthermore as a diuretic drug before the organomercurials appeared in the 1920s. Skin diseases were treated with ointments or plasters of the mercurials or quicksilver. Antiseptics were introduced by Semmelweis hand-washing with chlorinated water before deliveries in obstetrics and by Lister's antiseptic ritual with carbolic acid during surgical operations. Also organomercurial "antiseptics" were used but unfortunately these agents were bacteriostatic rather than bacteriocidal and allergic contact dermatitis has been observed. Today the problems are solved by sterilization and aseptic conditions. Penicillin appeared in the 1940s and chlorothiazide in 1957 and new effective agents have taken over in the treatment of diseases with mercurials.

Mercury-selenium association in antarctic seal hairs and animal excrements over the past 1,500 years.

Strong positive correlations between selenium (Se) and total mercury (HgT) contents in the liver of marine mammals and mercury mine workers in modern times have been documented in numerous investigations. Herein, we report a positive correlation between Se and HgT concentrations over the past 1,500 years in the seal hairs and in the lake sediments amended by seal or penguin excrements on King George Island (63 degrees 23' S, 57 degrees 00' W), West Antarctica. Because the changes in the input of Se and Hg into the marine environments of the studied sites do not seem to be synchronous, this striking correlation indicates a self-protection mechanism in Antarctic seals and penguins: Every time there is heavier Hg burden, more Se is accumulated to reduce the toxicity of Hg. This positive correlation between Hg and Se contents in the seal hairs and excrement sediments, however, becomes insignificant in the recent 50 years for unknown reasons.

Task- and time-dependent weighting factors in a retrospective exposure assessment of chemical laboratory workers.

A chemical exposure assessment was conducted for a cohort mortality study of 6157 chemical laboratory workers employed between 1943 and 1998 at four Department of Energy sites in Oak Ridge, Tennessee, and Aiken, South Carolina. Previous studies of chemical laboratory workers have included members within professional societies where exposure assessment was either limited or not feasible, or chemical processing employees where laboratory and production workers were combined. Because sufficient industrial hygiene records were unavailable for all four sites, weighted duration of employment was used as a surrogate for the magnitude of exposure. Potential exposure indices were calculated for each worker using number of days employed and weighting factors for frequency of contact and year of employment. A total of 591 unique laboratory job titles indicative of a chemical laboratory worker were collapsed into 18 general job title categories. Through discussions with current and retired workers, along with examination of historical organizational charts and job descriptions, the percentage of time with activities involving the direct handling of chemicals in the laboratory was estimated for each job title category. Scaled weighting factors of 1, 0.6, 0.3, and 0.05 were assigned to the job title categories representing 100%, 60%, 30%, and 5% of daily activities handling chemicals, respectively. Based on limited industrial hygiene monitoring data, personal radiation monitoring records, and professional judgment, weighting factors that declined 4% annually were applied to each year to account for improvements in laboratory technique, advancements in instrumentation, improvement in engineering controls, and increased safety awareness through time. The study cohort was separated into three categories of chemical exposures based on department level information: (1) inorganic, (2) mixed inorganic and organic, and (3) unknown. Potential exposure indices ranged from 0.15 to 6824.5 with a median value of 377.5 and a mean equal to 884.2. This exposure assessment method is useful for epidemiologic analyses when quantitative exposure data are absent or insufficient.

Millennial-scale records of atmospheric mercury deposition obtained from ombrotrophic and minerotrophic peatlands in the Swiss Jura Mountains.

Peat cores from two bogs were used to reconstruct changes in net atmospheric mercury deposition in Switzerland for the past 2-3 millennia. The two records were compared to assess the reliability of peat cores as archives of atmospheric mercury deposition. Net mercury accumulation rates and Hg(ex), an indicator of significant anthropogenic mercury contamination, were calculated for both cores. Both records showed stable background values (0.5-1.9 and 1.0-3.0 microg of Hg m(-2) yr(-1)). In both profiles, mercury accumulation rates began to increase during the 12th century, and Hg(ex) appeared during the 14th century. The late 19th and early 20th centuries have been studied in detail. The profiles match well with the history of local and global mercury emissions. The magnitude of increase from the pre-anthropogenic to anthropogenic period was also very similar in both records. Although the two sites are botanically very similar and lie only 3.5 km apart, accumulation rates at TGE were generally higher than those at EGR. This indicates that, although such records can be used to determine the chronologies of and relative changes in rates of atmospheric mercury deposition, differences in rates of mercury accumulation rates between sites do not necessarily indicate differences in deposition rates of mercury from the atmosphere.

Trace metals in ancient hair from the Karluk Archaeological Site, Kodiak, Alaska.

Considerable interest exists in characterizing the extent of changes in methylmercury exposures from preindustrial to modern-day times. Hair is often preserved over centuries and has been useful in determining the extent of dietary trace metal exposures, particularly methylmercury. We examined 16 human hair samples taken from human hair bundles buried in the soil of the Karluk One Archaeological site located near the current Karluk village on the Kodiak Archipelago of Alaska. Hair samples were analyzed for total mercury, methylmercury, selenium, and cadmium. The mean total mercury level was 1.33 ppm (SD = 1.09). The mean methylmercury level, however, was considerably lower than the total mercury concentration: the mean methylmercury level was 0.03 ppm (SD = 0.02). The mean cadmium level was 0.15 ppm (SD = 0.14) and the mean selenium level was 5.22 ppm (SD = 5.73). While the concentration of total mercury in the Karluk hair samples is comparable to those observed in ancient hair from other locations, direct methylmercury quantization demonstrated that methylmercury levels were less than 2% of the total mercury in these hair samples. Because the hair was subjected to a variety of environmental influences over the centuries, the possibility of degradation of methylmercury in the hair over the last 400 to 800 years cannot be ruled out. The use of hair from remains found in more protected frozen or dry environments may provide the best evidence for the extent of preindustrial exposures to methylmercury and other trace metals.

From mercury to malaria to penicillin: the history of the treatment of syphilis at the Mayo Clinic--1916-1955.

Between 1916 and 1955 the Mayo Clinic became recognized as one of the premier institutions specializing in the treatment of syphilis. First under the direction of John H. Stokes (1916-1924) and later Paul A. O'Leary (1924-1953), its Department of Dermatology and Syphilology, together with the members of the Clinical Cooperative Study Group, oversaw the establishment of standardized methods for the administration of the existing arsenicals and the introduction of new therapies. Malaria therapy, heat therapy, penicillin, and oxytetracycline each represented important advances in the treatment of syphilis and were extensively evaluated. Two important ancillary benefits of syphilis treatment were the development of routine intravenous techniques, which would later prove invaluable for the administration of antibiotics and cancer drugs, and the establishment of large cooperative clinical trials, the first of their kind. Under the leadership of Stokes and O'Leary the department produced a stream of pivotal clinical research that contributed to the effective management of syphilis in the United States.

Tan, cinnabar, as drug of longevity prior to alchemy.

Alchemy as the art of gold making never existing and had no beginning. It arose as the cult of longevity using simples, like gold and cinnabar, as drugs of longevity. It became alchemy on making the first synthetic drug, Chin-Yeh, Gold-plus-herbal juice, and reached its ideal with Chin-Tan, Gold-plus-cinnabar. The former was red colloidal gold, the latter vermilion with traces of gold. As inscribed character Tan shows crude cinnabar, pulverized, lavagated and filtered on a rectangular piece of cloth.

[Lessons from the history of therapy--therapeutic optimism and its pitfalls]. / Lehren aus der Therapiegeschichte--der therapeutische Optimismus und seine Tücken.

If we are to help patients effectively, our understanding of diseases and our therapeutic potential should, again and again, just be somewhat better than they actually are. Throughout the ages this has been the fundamental situation in medical practice. The response on the physician's part has nearly always been an attitude of therapeutic optimism. At all times physicians--and patients also--have relied on therapeutic principles and remedies based on professional experience and medical theory. In conjunction with the (generally recognized) healing powers of nature, and of (unrecognized) autosuggestion, this has led to many satisfactory and even remarkable cures. Examples from antiquity to the 19th century are quoted, and the snags of an over-optimistic attitude become evident, viz. a rational therapy is no better than the underlying pathogenetic theory; exaggerated therapeutic activity may cause useless torment to the patient (a point already made by Hippocrates); the optimistic physician or the enthusiastic pioneer of a new remedy may be blind to toxic side effects or the development of addiction. To sum up: therapeutic optimism is fine--but don't overdo it!