Permeation, gloves

Chemical permeation is rated in tests under EN 374-3. The breakthrough time of a chemical through a glove is quoted as a permeation index ... 

Table IV. Chemical Permeation Results from the Matching by Product Model Product Model Edmont 37-155 Nitrile Glove...

DNB readily permeated the latex gloves used for protection has enormous implications in the occupational setting because it shows that this kind of protection is ineffective. Limitations of this study include small sample size, concomitant exposure to other chemicals, and lack of complete information on exposure dose. 

Because of their widespread use in the American workplace, butyl rubber, nitrile latex, neoprene latex, poly(vinyl alcohol), surgical rubber latex, and Viton elastomer were chosen for the present studies. The composite/bonded substances of this study were not in all cases presently available as commercial material for protective garments, but rather were chosen to determine their potential for resistance to solvent permeation. Likewise, Teflon gloves were included in these studies simply because they are commercially available. 

Most of the homogeneous, nonbonded protective garment materials chosen for these studies were obtained from commercial sources and were thus representative of materials available to workers in the U.S. The composite materials were not generally used as glove materials, but rather were chosen as being representative of material available for use in coats or aprons or were experimental or prototype materials. In the present work, the results of these permeation studies are presented in three ways ... 

Weeks, Jr., R.W. Dean, B.J., "Permeation of Methanolic Aromatic Amine Solutions Through Commercially Available Glove Materials, Am. Ind. Hyg. Assoc. J. 1977, 38, 121. 

The extreme toxicity of dimethylmercury was demonstrated tragically by the 1997 death of Professor Karen Wetterhahn of Dartmouth College. Dr. Wetterhahn was exposed to dimethylmercury from an accidental spill of about two drops of this liquid onto the latex rubber gloves she was wearing for protection. The lipid-soluble compound permeates latex and skin, and Dr. Wetterhahn died less than a year later from neurotoxic effects to the brain. 

S.A. Corlett, et al., Permeation of ifosfamide through gloves and cadaver skin. Pharmacol. J. 247 R39, 1991. 

Table 6.4 Permeation of three two-component mixtures through two glove materials (U.S. EPA, Guidance Manual for Selecting Protective Clothing...

PPE materials having a continuous polymeric film are likely to resist permeation and penetration by all solid formulations and thns act as a barrier to solids contact with the skin. For solids, glove featnres snch as fit, ganntlet length, durability, etc. as discussed previously, are the key issues for glove selection decisions. 

Chemical resistance factors are more important for aqneons solntion formulations and most important for the formulations that contain an organic solvent. Most common glove materials, with the exceptions of polyvinyl alcohol and very thin (<0.2 mm) natnral rubber gloves, are highly resistant to water and wonld be expected to provide good barriers to permeation by formulations that contain no organic solvents. 

The solntions that contain an organic solvent usually in the form of emnlsifiable concentrates and field application dilutions of such concentrates, represent the greatest potential challenge to the barrier effectiveness of polymeric gloves. Many of the solvents can severely degrade or permeate the glove materials when in nndilnted form. 

Since the early 1980s, the EPA has compiled all the available infoimation form the government laboratories, equipment mannfactnrers, and snppliers into a database. Permeation data for several of the solvent liquids listed in Table 6.5 are available for commoi glove matedals from this database. 

Table 6.6 is provided as a final aid for protective glove selection decisions. Table 6.6 identifies the preferred glove types as well as those not recommended for use with pesticide formulations containing various carrier solvent types. The glove types identified as preferred are those that consistently provide the best permeation resistance to pesticide formulations and undiluted carrier solvents within each chemical classification identified. The glove types identified as not recommended are those that consistently provide very poor permeation resistance. Also note that the recommendations in Table 6.6 are... 

Ehntholt, D. J., Bodek, 1., Doerfler, T. E., Schwope, A. D., StoUd, T. J. and J. Valentine, Permeation Resistance of Polymer Glove Materials to Various Strengths of Active Pesticide Ingredients and Carrier Solvents, Draft Internal Report, EPA Offfice of Research and Development Contract No. 68-03-3293, Cincinnati, (1989). 

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