Subject: Mothproofinging
Victoria Gill <endangeredtextiles [at] ozemail__com__au> writes >I have recently been working on some relatively contemporary woollen >textiles works (tapestries, weavings and cross stitches) all of >which incorporate yarn which has been mothproofed. I suspect the >chemicals most likely used are Dieldrin methoxychlor (brand name >Mitin FF) Eulans or/and even DDT. These compounds are all organo >chlorides, long lasting and washable. ... Long answer: I looked into various chlorinated and a few non-chlorinated mothproofing agents (ICOM-CC 1984, "Mothproofing Museum Textiles") and I found some confusion because not all chlorinated products were water soluble nor fast to washing ('low washfastness'). DDT and Dieldrin were, if I remember correctly, soluble in drycleaning solvents, not water. Thus, *handling* would expose me to the pesticide--the stuff would be as happy to come off on my hands as to stay on the fiber. In dye terms, these agents are not substantive to the fiber. Washing (wet cleaning)would not be effective, but would give you a contaminated waste water problem. Drycleaning might resolublize your agent. Some agents, like DDT can also crystalize out--and might be vacuumed off. At the other end of the spectrum, Mitin FF (a substituted urea with dichlorophenyl ether) and Edolan U (Eulan U33 in Europe, a chlorophenyl ether with methyl sulfonamide) are different. They are substantive to the fiber, like a dye. Mitin FF is applied at the boil, but Edolan in warm water, as an aftertreatment (the term 'aftertreatment' refers to after manufacture, not in the loose fiber stage. Some aftertreatments are suitable for conservation uses, some are not. Edolan U was feasible but its potential toxicity for applicators and its waste water effluent led to its removal from the market. (Some natural history museum staff were spraying on Edolan U in an isopropanol solution, but this would not be substantive to the fiber (or fur)--leading to a problem with handling the stuffed animals.) I have not been focusing on the issue recently but recollect the use of 11% pyrethrin as the only mothproofing aftertreatment agent currently available. This is a skin irritant and not substantive to the fiber. It will bleed off in washing--it may be removed to your wash water; pyrethrin breaks down with ultraviolet light and is biodegradable. Before disposal, you would have to review the label directions carefully. Pyrethrin, the Edolan/Eulan U33, and the Mitin FF will cause slightly faster yellowing of wool than would otherwise occur with light ageing. Of course, for long undisturbed display of large cumbersome, fragile wool handings and carpets such yellowing may be preferable to carpet beetle or clothes moth infestations. Barbara Reagan did a wonderful job with a group paper for the AATCC, "Effect of Insecticides on the Colorfastness of Acid and Disperse Dyes on Nylon and Polyester" can be found in the Textile Chemist and Colorist January 1984, Volume 16, Page 25+ (available at <URL:http://www.aatcc.org/> Acid dyes are also used on wool. Though the substrate (wool vs. nylon or PET) affects the outcome, you will find which agents altered the dyes the most egregiously. Short answer: Slightly more yellowing of wool; mothproofing agents were not widely used on cellulosics (why waste money, time, chemicals?). Wash your hands frequently (wear disposable gloves and dispose of them), use a HEPA filtered vacuum cleaner, look for crystallinity, find out whether the objects were commercially treated (aftertreated) or treated by drycleaners, homeowners (DDT, etc). Get an organic chemist to run an extraction for gas chromatography and/or get an inorganic analysis for halogens on materials that you question. Your agricultural extension service (pest control) and industrial hygienists (health department) should provide you with additional advice once you have identified your specific concern. *** Conservation DistList Instance 18:29 Distributed: Wednesday, January 5, 2005 Message Id: cdl-18-29-001 ***Received on Thursday, 23 December, 2004