As the concerns over use of ayurveda medicines containing bhasmas of heavy metals are on rise, we will take a closer look at the process of preparing bhasmas and use of heavy metals prescribed in ayurveda.
INTRODUCTION Ayurveda, the age-old medical system of India isattracting attention as one of the leadingcomplementary and alternative medical science. The major use of herbal ingredients proves to beeffective and minimally toxic to the patients. The benefits of Ayurvedic medicines often resultfrom synergistic action of multiple active chemicals. Ayurvedic medicines are not only derived from plantbut also have mineral, metal and animal origindrugs.
HEAVY METAL TOXICITY CONCERNS The use of metallic preparations as single drugs or asingredients in many Ayurvedic medicines has evokedconcern and debate in the scientific and publicforums in the recent times. Some studies has warned that users of Ayurvedicmedicines may be at risk for heavy metal toxicity andsuggested that testing of Ayurvedic medicines fortoxic heavy metals should be mandatory.
SORRY! BUT IT’S NOT TRUE!! This observation is unacceptable to many Ayurvedicphysicians and Rasavaidyas (Those who preparemetallic preparations). Their contention is that so called heavy metalswere not heavy on the human body and thatAyurvedic medicines containing heavy metals(used in the form of Bhasmas) werecompletely safe to use.
RASASHASTRA (INDIAN ALCHEMY) The Rasashastra evolved from Alchemy which aimedat finding magic substance that would transmutebase metals like lead, tin, mercury and copper intothe noble ones(gold and silver). The invention of mercury was the turning point inthe development of Rasashastra. Mercury is knownas Rasa and the whole Rasashastra is based on itswonderful and miraculous properties. Rasashastrawas enriched by additions of metals, alloys, materialsobtained from minerals and ores.
METALS FROM CLASSIC TEXTS Charaka (1200BC) primarily used plants as medicines.The idea of making metals absorbable and effective tohumans, he described simple procedure of heating andquenching the metals in cow urine. In Sushruta samhita(10BC), we can find the first mentionof mercury. In Ashtanga sangraha the method of preparing bhasma isdescribed. The main advance of Rasashastra was seen from 9th to18th century. Nagarjuna is credited as the foremostauthority in the development of Rasashastra.
HEAVY METALS A heavy metal is one with a specific gravity of 5gmcm-3 or more. They are stable elements and cannot be metabolizedby the body. Some heavy metals such as zinc, copper, cobalt,chromium, iron and manganese are required by bodyin small measures. These same elements can be toxic in largerquantities. Heavy metals may enter the body in food, water, air,or by absorption through skin.
BHASMAS OF METALS The heavy or toxic metals in elementalform are toxic but those in compound formi.e. bhasma are safe for humans. Bhasmas are made from various metals,metal mixtures and alloys. The way they are prepared, evaluated andtherapeutically used leaves no doubt abouttheir safety to the humans.
SHODHANA It is a process of purification anddetoxification by which physical andchemical impurities along with toxicmaterials are eliminated. Different procedures like sprinkling,absorption, frying, lavigation, melting andquenching, trituration, dipping are usedaccording to the selected substance.
BHAVANAWet bhavana is the process ofgrinding in which materials areground with specific liquid media for aparticular period.The process leads to unique andsuitable physicochemical changes andpotentiate the efficacy of material.
MARANA (CALCINATION) The process whichconverts thepurified metals andminerals intobhasma (Ash) aftersubjecting them tolavigation andincineration iscalled as marana.
PROCESS OF MARANAMISHRANA BHAVANACHAKRIKANIRMANPUTAMMARANA
CHANGES DUE TO MARANAReduction in particle size.Conjugation of trace elements.Elimination of unwantedelements.Formation of desirablecompound.
QUALITY CONTROL OFBHAMAS PHYSICALPARAMETERSVaritarUnnamaRekhapoornatvaShlakshnatvam CHEMICALPARAMETERSVarnaGatarasatvamNishchandratvaApoonarbhavatva
KUPIPAKWA RASAYANA THIS IS AN UNIQUE AND DIFFERENT PROCESSOF PREPARING BHASMAS. IN A SPECIALLY BUILT FURNACE, EARTHENVESSEL FILLED WITH SAND IS PLACED. IN THEVESSEL, A COATED GLASS BOTTLE WITH AMIXTURE IS KEPT. HEAT IS GIVEN FROM BELOW IN ASCENDINGTEMPERATURES FOR 24 TO 72 HOURS. THE DESIRED MEDICINE IS OBTAINED FROMNECK AND BOTTOM OF THE BOTTLE.
ASCENDING HEATINGMANDAGNI –200-300 CMADHYAMAGNI– 600-800 CTIVRAGNI –1100-1300 C
RASASINDURANECK OF THEBOTTLE BEINGOBLITERATEDBREAKING OFBOTTLETAMRABHASMA ANDRASASINDURA
BHASMA DISCUSSION Many researchers and students are interested toknow about chemical nature of end product of thebhasma process. A metal is heated to high temperature in kiln belowits melting point in an inadequate supply of air whenit undergoes thermal decomposition or a phasetransition other than melting. As a result the metalbecomes friable and may undergo oxidation orreduction. The entire process of bhasma is thus oneof producing a salt of metal, mostly an oxide. Thebhasma process has to be done several times over.
BHASMA (CONT..) After successive calcinations much smallerparticle sizes are reached. Ultimatelyparticle sizes reach colloidal scales (from afew microns to a few nanometers). BHASMAS ARE REAL NANOPARTICLES. These sizes help in better absorptivity andso effective drug delivery.
BHASMA (CONT..) In each cycle of calcinations the oxidation processwould progress in a different way and variousorganometallic complexes are formed intermediatelybefore finally achieving desired pure metal oxide orsulfide. For nearly all the metals the methods of bhasmapreparation differ among the text themselves. Thedifferences are in accompaniments, peaktemperatures and exposure span in each cycleleading to oxide variants.
TOXICITY ASPECT The concerns raised are about metal content and notabout metal toxicities among populations resulting fromuse of such medicines. The chemical forms of metal can impact bioavailabilityand toxicity as inorganic compounds and in prescribeddosages; they are less likely to accumulate in the body. With particle sizes in micron, the absorptivity of metalbhasmas is undoubtedly better than an ordinary mineraltaken in powdered form. These preparations are in usefor more than thousand years; HENCE ALLBHASMAS ARE NON TOXIC.
RECOMMENDEDPRECAUTIONS Metallic preparations can be harmful and toxic ifthey are not prepared properly. Ayurvedic medicines should not be allowed to besold as herbal medicines or supplements and shouldnot be available at grocery stores. People should consume these herbo-mineral-metallicpreparations strictly only under medical supervisionwith appropriate dosage, anupan (drug vehicle) andfor advised period only. Patients should also observe prescribed diet andlifestyle changes.
THE WAY AHEAD… AYUSH and FDA should try to take research projects forevaluation of toxic effects of metallic formulations. The labels on the containers of these medicines shouldclearly mention the presence of metals and declare theirquantity. Research work regarding short term and long termtoxicities of these medicines should be supported andpublished according to global standards. Ayurveda is facing lot of hurdles to recognize itself as aglobal medical system. Approach of individualizedtreatment and use of heavy metals are the maindeterrents. But, government should try to persuade thewestern countries about the recognition of ayurveda.