Dyes Molecular Weight Less Than 500 Da

ALLERGENFocus Sharon E. Jacob, M.D. Claudia C. Ramirez, M.D. that affected patients should avoid, along with tips to avoid cross-reactions and exposures. CONTACT DERMATIDES The contact dermatides include allergic contact dermatitis (ACD), irritant contact dermatitis and contact urticaria. Irritant contact dermatitis, the most common form, accounts for approximately 80% of environmental- occupational based dermatoses. Contact urticaria (wheal and flare reaction) represents an IgE and mast cell-mediated immediate-type hypersensitivity reaction that can lead to ana- phylaxis, the foremost example of this being latex protein hypersensitivity. While this is beyond the scope of this section, we acknowledge this form of hypersensitivity due to the severity of the potential reactions and direct the reader to key sources.2,3 ACD is an important disease with high impact both in terms of patient morbidity and economics. ACD represents a T-helper cell Type 1 (Th1) Focus on 2000 Allergen dependent delayed-type (Type IV) hypersensitivity reaction.The instigating exogenous antigens are primarily small lipophilic chemicals (haptens) with a of the Year: Textile Dyes molecular weight less than 500 Da. On BY SHARON E. JACOB, M.D., AND CLAUDIA C. RAMIREZ, M.D. direct antigen exposure to the skin or mucosa, an immunologic cascade is ini- tiated which includes cytokines, i.e. n 1997 the Federal Drug Administration granted an indication for the use of the interleukin 2 (IL-2) and interferon thin-layer rapid-use epicutaneous (T.R.U.E.) test as a valuable, first-line screen- gamma (IFN-γ), T cells and Langerhan Iing tool in the diagnosis of allergic contact dermatitis (ACD). Many dermatolo- cells. This complex interaction leads to gists and allergists utilize this standard tool in their practice and refer to contact der- the clinical picture of ACD. matitis referral centers when the T.R.U.E test fails to identify a relevant allergen. Specifically, the T.R.U.E. test screens for 46 distinct allergens in addition to the CLINICAL ILLUSTRATION Balsam of Peru mixture. The test is thought to adequately identify an allergen in A mechanic presented to the approximately 24.5% of patients with ACD.1 This being said, many relevant allergens University of Miami Contact Dermatitis are not detected by use of this screening tool alone and, for this reason, “Allergen Clinic for evaluation of longstanding Focus” has been expanded to cover the notorious allergens that have been desig- generalized pruritus, for which he had nated by the American Contact Dermatitis Society (ACDS) as Allergens of the Year. seen multiple dermatologists and psy- “Allergen Focus” is a column designed to concentrate on common allergens chiatrists. Of note, numerous prurigo and is intended to answer some of the most frequent questions relating to their nodules and scars were present on his origin and most common uses. Each column also highlights appropriate products arms and legs and there were distinct 28 JANUARY 2007 SKIN & AGING areas of sparing in the location of his printed silks, but to his chagrin this undergarments. measure only made silks more popular. BIRD’S EYE VIEW ON THE HISTORY OF BLEACHING IS DISCOVERED TEXTILE DYES In 1774 the bleaching properties of The earliest written record of the use chlorine (by destroying vegetable colors) of natural dyes was found in China, was first employed by Scheele, a Swedish dated 2600 BC.4 These early records chemist. He had noted the bleaching denote the ancient Chinese methods effect on a cork in a bottle of hydrochlo- for dyeing silk using various dyes ric acid and this discovery was of enor- obtained from plants.These plants were mous commercial importance. selected and harvested by the dyer and The practical application of this new boiled in water to form the dyebath. chemical in bleaching cloth soon sup- Mordants (metal salts such as tin, planted the Old Dutch process of chrome, iron, copper, alum, etc. used to “crafting” — that is, extended sun- fix natural dyes to fabric) were also uti- bleaching by spreading the cloth upon lized to broaden the range of colors the grass. within the same dyebath base.5 This discovery was paramount to tex- In early documented European his- tile manufacturers, as the old process of tory, the Phoenicians used their bleaching consumed an entire summer renowned dyeing skills and beautifully to whiten a single piece of linen. The colored fabrics to enhance trade with new process reduced the period to a other countries. few hours.6 Colors were also used for sociological Until this time, the great subject of classification. For example, in ancient organic chemistry had remained practi- Rome yellow was only used for dyeing cally unexplored. Under Scheele’s bridal garments5 and Caesar identified direction, new methods of isolating and his status with the color purple. The THE VENETIANS studying animal and vegetable dye Venetians further developed the art of products were introduced, and a large FURTHER DEVELOPED dyeing with imported indigo and Brazil number of previously unknown acids wood from India.5 Of interest, the THE ART OF DYEING WITH and other organic compounds were Portuguese later used the Brazil-tree to IMPORTED INDIGO AND BRAZIL able to be reproducibly prepared.6 name the newly discovered South Prior to Scheele’s advances, older green WOOD FROM INDIA.5 American country where many of these pigments were based on copper carbonate. trees had also been found. With Scheele’s new methodologies, During the tenth century, the first THE LAW OF THE DIET he was able to create a new spectrum of syndicate of dyers was created in green based on the properties of the OF 1577 PROHIBITED THE USE Germany, the Wool Dyer’s Guild.5 The compound arsenic. discovery by Pizarro and Cortez of cot- OF INDIGO (FROM INDIA) These favored green dyes were used for ton in Central and South America IN GERMANY, coloring paper, cotton and linen.7 (c. 1519) brought to Spain brightly Interestingly, the wallpapers containing IT BEING DESCRIBED AS A printed fabrics from the natives.4 Scheele’s Green were implicated in the “PERNICIOUS AND arsenic poisoning of Napoleon Bonaparte!8 THE DYEING INDUSTRY BOOMS CORROSIVE DYE”.5 The discovery of the Americas gave a THE ERA OF SYNTHETIC DYES IS BORN great impetus to the art of dyeing, intro- In 1856 during Easter vacation from the ducing logwood, fustic and cochineal Royal College of Chemistry, an English (vegetable coloring matters). import of logwood dye in 1620 to chemistry student, William H. Perkin, Thereafter, the dyeing industry restrict commerce with Spain, who had accidentally synthesized mauve (an aniline boomed, guilds formed and regulations been importing it from the Americas,5 basic dye, derived from coal tar).4 and laws were created to protect local but dyers managed to acquire it under While attempting to create a possible industry. For example, the Law of the Diet other names. cure for malaria, he chemically synthe- of 1577 prohibited the use of indigo (from On the other hand, King James II pro- sized quinine, which when oxidized India) in Germany, it being described as a hibited exportation of undyed cloth to help yielded a beautiful violet-colored mat- “pernicious and corrosive dye”.5 reinforce the home industry for English ter with great tinctorial powers (ability Kings passed laws to protect com- dyers (over Scottish dyers) in 1688.4 to impart color on another object). merce and direct taxation. For example, Furthermore, in 1708, William III This was the beginning of the era of James I of England prohibited the signed a law banning the importation of synthetic dyestuffs and an important JANUARY 2007 SKIN & AGING 29 AT THE NEW YORK WORLD FAIR PREMIER IN 1939, THE FIRST PAIR OF NYLON STOCKINGS, WHICH WERE THOUGHT TO HAVE BEEN DYED WITH FEDERAL DYESTUFF DISPERSE DYES, WERE FORMALLY INTRODUCED TO THE COMMERCIAL MARKET.14 WITHIN A YEAR, THE NYLON STOCKING CRAZE WAS IN FULL FORCE, WITH 64 MILLION PAIRS SOLD! landmark in industrial chemistry. In fact, perous history of producing non-sensi- Around this time, Harvard chemist, most of the labor-intensive vegetable tizing pants. Wallace Hume Carothers at DuPont pigment processes have now been In addition, this American-based developed their most notorious innova- replaced by the various synthetic coal-tar company is notable for being one the tion, Fiber 66 (a.k.a. Nylon).13 And, colors, because they were faster coloring first and few to use American-based even though it took more than a decade and easier to apply.This allowed for mass dyes and produce their product to bring this fiber to the consumer mar- production of standardized materials and domestically, which allowed them to ket, its debut was hallmarked. At the the boom of the garment industry. maintain production despite changing New York World Fair premier in 1939, The Post Office Department, the world events. the first pair of nylon stockings, which predecessor of the United States Postal In 1914, for example, 90% of the notably are thought to have been dyed Service, was founded in 1775, but offi- dyestuffs used by North American man- with Federal Dyestuff disperse dyes, cial uniforms weren’t worn until after ufacturers were imported. This specifi- were formally introduced to the com- 1868, when Congress passed legislation cally became a problem during WWI, as mercial market.14 Within a year, the authorizing use of uniforms by letter many of the dyes came from Germany.4 nylon stocking craze was in full force, carriers. These uniforms were cadet The limited availability of dyes during with 64 million pairs sold! blue-gray with black trim.9 These dark- the War, led Congress to pass a protec- In 1942, production of nylon stock- colored uniforms, especially those made tive duty on homeland dyestuffs to ings ground to a halt, as nylon resources from synthetic or blended fabrics, were encourage domestic manufacture.

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