The Biological Stain Commission is an organization that provides third-party testing and certification of dyes and a few other compounds that are used to enhance contrast in specimens examined in biological and medical laboratories. The BSC is a 95-year-old organization well known to many thousands of scientists, worldwide but especially in N America, who buy BSC-certified stains for stainingmicroscopic preparations and for making selective culture media for bacteria. Manufacturers and other vendors submit samples from their batches of dyes to the BSC's independent laboratory in Rochester NY. The BSC's certification label on a bottle of dye indicates that the contents are from a batch that passed the tests for chemical purity and for efficacy as a biological stain. These tests are published. Changes to tests and additions to the list of stains eligible for certification are published from time to time in Biotechnic & Histochemistry and are summarized on the commission's web site. The BSC is a non-profit organization, incorporated in the State of New York, for the purpose of ensuring a supply of high quality stains for use in biological and medical laboratories. Its origins date from 1922, when vendors of biological stains in the USA had exhausted their stocks of pre-war dyes imported from Germany. American dye manufacturers were unable to produce products that were consistently reliable in histological microtechnique and bacteriology. The commission's testing laboratory was initially at the Agriculture Experimental Station in Geneva, NY, directed by Harold J. Conn. Since 1947 the laboratory has been located at the University of RochesterMedical College, Rochester, NY. Currently 57 individual dyes and about 5 mixtures of different dyes are eligible for testing and certification by the BSC. The assays and other tests used in the commission's laboratory are all published, making the required standards known to both vendors and users of biological stains. The commission's web site includes instructions for submitting samples of stains for testing and certification. Since 1925 the BSC has published a scientific journal, named Stain Technology until 1991, when the name was changed to Biotechnic & Histochemistry. Biological Stains, a book about the chemistry, testing and applications of dyes and other colorants in biology and medicine, has been published by the BSC since 1925. The first seven editions were by H. J. Conn. The eighth and ninth editions, retitled Conn's Biological Stains, were by Ralph Dougall Lillie, who added many dyes and chromogenic reagents and provided extensive tables of data for classification, nomenclature and solubilities of dyes. The tenth and most recent edition of the book has 28 chapters by multiple authors; 18 are by Horobin alone. The BSC has also sponsored three editions of History of Staining, originally by Conn and later by Clark and Kasten. Education about stains is another mission of the BSC. Questions sent in by way of the BSC's website are passed on to appropriate experts and answered privately by email, usually within a few days. This free service provides confidential information to users, vendors and manufacturers, and also informs the BSC about current problems. In December 2018 the BSC added to its website an online glossary of hundreds of words and short phrases used in the field of biological stains. The annual meetings of the BSC are held on the first or second weekend in June, in cities easily accessible by air from major centers in North America and Europe. These meetings include scientific sessions with presentations by invited speakers in such disciplines as cancer biology, neuroscience, pathology and plant sciences. There are also informal presentations and exchanges of information among academic biologists, medical scientists, pathologists, and representatives of companies that manufacture and sell biological stains.
