RSDL

Reactive oximes and their salts, such as potassium 2,3-butanedione monoximate found in commercially available RSDL, are extremely effective at rapidly detoxifying nerve agents. Some chloroisocyanurates, similar to those found in the CASCAD, are effective at detoxifying V-series agents and so is oxone, a peroxymonosulfate triple salt. 

Reactive Skin Decontamination Lotion (RSDL) Pretreatment Topical In vitro, human skin 18-fold reduction in skin absorption rate, may partially extract SM from the skin reservoir Chilcott et al. (2002)... 

Taysse, L., Daulon, S., Delamanche, S., Bellier, B., Breton, P. (2007). Skin decontamination of mustards and organophos-phates comparative efficiency of RSDL and Fuller s earth in domestic swine. Hum. Exp. Toxicol. 26(2) 135 1. 

FIGURE 71.3. RSDL reactive skin decontamination lotion... 

The product was also compared to Fuller s earth in a pig model. The potency of the RSDL/sponge was statistically better than Fuller s earth against skin injury induced by sulfur mustard, observed 3 days post-exposure. RSDL was more efficient than Fuller s earth in reducing the formation of perinuclear vacuoles and inflammation processes in the epidermis and dermis. The potencies of the RSDL/sponge and Fuller s earth were similar to severe inhibition of plasma cholinesterases induced by VX poisoning. Both systems completely prevented cholinesterase inhibition, which indirectly indicates a prevention of toxic absorption through the skin (Taysse et al, 2007). 

However, there are some caveats for the use of RSDL. The application of RSDL directly to open wounds impaired wound strength and decreased collagen content in the early phases of wound healing. This may have clinical implications for the treatment and outcomes of chemical casualty combat trauma (Walters et al, 2007). RSDL is also reported to be flammable. 

T. (2004). Clinical safety of reactive skin decontamination lotion (RSDL). Toxicologist 78 354-5. 

Reactive Skin Decontamination Lotion (RSDL) has recently been approved for procurement by the U.S. military (F-Z-EM 2007). RSDL is currently marketed by E-Z-EM, Inc. and is a patented, broad spectrum, skin decontamination lotion that is used to remove or neutralize chemical threat agents and biological warfare agents such as trichothecene mycotoxin (T2 toxin), which can cause severe skin and eye irritation. RSDL was originally developed by the Canadian Defense Research Establishment and consists of 1.25 molar potassium 2,3-butanedione monoximate in poly-etheylene glycol monoethyl ethers with 10% w/v water (Sabourin et al. 2001 Lukey et al. 2004). 

E-Z-EM News Release, 2007. E-Z-EM S RSDL Product approved for procurement by U.S. Defense Department, March 20, available at http //www.ezem.com/news/news. cfm article id=76 (accessed September 17, 2007). 

Though an ideal decontaminant may be difficult to attain, many alternatives exist that are readily available and meet many basic requirements, van Hooidonk et al. (1983) evaluated a variety of household products as decontaminants for VX, soman, and sulfur mustard. His paper provides an excellent comparison of these readily available decontaminants to include flour, soapy water, talcum powder, and tissue paper. We have selected several other candidate decontaminants that are under investigation, in advanced development, or currently fielded. These include the currently fielded U.S. Department of Defense skin decontaminants (M291 Skin Decontamination Kit [SDK], 0.5% hypochlorite, and 1% soapy water). Reactive Skin Decontaminant Lotion (RSDL), Diphoterine, Sandia Laboratory s Decontamination Foam, and the Decontamination Sponge. 

RSDL. In 1995, the Canadian Defense Research Establishment at Ottawa and Suffield developed and patented a liquid skin decontaminant for CWA exposure named RSDL. RSDL is a formulation of potassium 2,3-butanedione monoxime (as free oxime and potassium salt) in a solvent of polyethylene glycol monomethylether (MPEG) of 550 nominal molecular weight with 10% w/w water (pH 10.6) (Sabourin et al., 2001 Bide et al., 2005 Material Data Safety Sheet, 2006). 

RSDL is currently manufactured by E-Z-EM, Inc (Lake Success, NY) and was selected to gradually replace the M291 kit for U.S. military. The Milestone C decision was made on March 16, 2007. RSDL is currently fielded by Australia, Belgium, Canada, Ireland, the Netherlands, New Zealand, Slovenia, and Sweden. This lotion has the benefit of being a wet decontamination system, which is generally more effective than dry systems. 

The effectiveness of RSDL at blocking damage caused by nerve and blistering agents was tested... 

The FDA, under 510(k) file 023969, has approved RSDL has as a medical device (FDA 2003a) and has reported that RSDL neutralizes the effects of many agents, including VX, G series agents, sulfur mustard, and T-2 fungal toxin (FDA, 2003b). 

One drawback that may limit the soldiers desire to use RSDL in the field, is that RSDL leaves an oily residue on the skin that makes one s hands slippery and makes handling weapons more difficult. 

Several decontaminants are readily available for CWA exposure. The trae measure of effectiveness requires that all products be tested identically, to include soapy water as van Hooidonk et al. (1983) did so well for common household products. The most comprehensive data available are the studies conducted at the USAMRICD (Braue, 2006 Hanssen et al., 2006) which directly compared the efficacy of M291 SDK, RSDL, 0.5% bleach, and 1% soapy water challenged with soman, cyclosarin, VX, and VR in the clipped haired guinea pig model. The most important guiding principle of decontamination is rapid removal of the threat agents from the skin. This principle supersedes seeking out sophisticated decontaminants immediately after CWA exposure. The immediate use of soapy water would offer far better results than the best possible decontaminant that was delayed more than 30 min in its use. Future evaluation of potential decontaminants should consider all of the discussed factors to determine the best product. 

FDA, Letter from the Food and Drug Administration to the US Army, dated March 25, 2003. Letter authorizing the marketing of RSDL in the United States, 2003a. 

Material Data and Safety Sheet for RSDL available on the E-Z-EM Inc. web page http /www.rsdecon. com/ezem.htm, 2006. 

Canada RSDL 0 Reactive liquid Polyethylene glycol base, potassium butadiene monoximate... 

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