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At least 19 recordsLinked to original sources
PubMed1975

Handling and staining epoxy resin sections for light microscopy.

Epoxy resin sections 0 1-1.0 mum thick of specimens embedded for electron microscopy, were collected from the ultramicrotome using strips of cover slip, and, after drying on a hot plate, were bulk stained in specially made troughs. After treatment with periodic acid, the sections were stained first in basic fuchsin at 70 degrees C and then in alkaline methylene blue at room temperature. The handling technique allows accurate collection of serial sections without interrupting the sectioning process, and the stain combination is suitable for different specimens in different epoxy resins and is unaffected by storage for more than 1 year.

Epoxy Resins↗
PubMed1977

Patch testing with low molecular oligomers of epoxy resins in humans.

Thirty-four patients sensitive to epoxy resin were patch tested with oligomers of epoxy resin. All reacted when tested with MW 340 oligomer. Twenty-three were tested with MW 624 and MW 908 oligomers and seven with MW 1192 oligomer; none reacted. Eight patients tested with commercial mixtures of epoxy resins with an average MW 1280 and MW 1850 reacted to these resin mixtures which contained the MW 340 oligomer. The MW 340 oligomer seems to be the main ingredient responsible for contact allergy to epoxy resins in humans.

Allergens↗
PubMed1977

Allergenicity of epoxy resins in the guinea pig.

The sensitizing capacity of epoxy resins of diglycidylether-Bisphenol A type was investigated using the "guinea pig maximization test". One isolated resin had a molecular weight (MW) of 340, which is the lowest among this type of epoxy resin. The other resins were mixtures with different MWs. Their distribution is not known, but only their average MW. The low molecular weight resin sensitized all of the animals and can be classified as an extreme allergen. The sensitizing capacity decreased in inverse proportion to the increase in the average MW of the resin mixtures. The cross-testing also indicated that the resin mixtures with higher average MW contained enough of the low MW resin (MW 340) to render this resin a sensitizer. Bisphenol A did not sensitize the animals at all but epichlorhydrin sensitized 60%. It is evident that in order to formulate hypoallergenic epoxy resins it will be necessary to achieve sensitization of animals with isolated resins of varying molecular weight.

Allergens↗
PubMed1975

Ethylenediamine sensitivity from exposure to epoxy resin hardeners and Mycolog cream.

Sensitivity to ethylenediamine and to epoxy resin hardeners was found in three patients with long standing contact dermatitis. In one patient, a young man, the sensitivity was elicited by occupational contact with epoxy resin hardeners and subsequently sustained by use of Mycolog cream. In two patients, both elderly women, the condition was only due to use of Mycolog cream. These case histories and test results indicate that use of Mycolog cream can result in occupational disease viz. contact dermatitis from epoxy hardeners.

Adult↗
PubMed1978

Simple methods for demonstration of epoxy resins of bisphenol A type.

Low molecular weight oligomers of epoxy resins of bisphenol A type are common sensitizers. For demonstrating the presence of sensitizing oligomers of these resins, two simple methods are described. The first one, a colour reaction, demonstrates the presence of the bisphenol A skeleton. If this test is positive, thin-layer chromatography is carried out to demonstrate the presence of low molecular weight oligomers of epoxy resins. Some practical applications are reported.

Chromatography, Thin Layer↗
PubMed1977

Better epoxy resin embedding for electron microscopy at low relative humidity.

In the absence of other factors known to influence sectioning properties, high environmental relative humidity is shown to yield poorly embedded tissue. Humidity-related effects are avoided if the following embedding precedure is used; impregnate tissues using the following solutions 1) 70% alcohol - 5 minutes, 2) 95% alcohol - 2 x 15 minutes, 3) absolute alcohol - 3 x 20 minutes, 4) acetone - 2 x 15 minutes, 5) 1:1 mixture of acetone-epoxy resin (DDSA, 63.4 g; Araldite 502, 5.6 g; Epon 812, 39.4 g; DMP-30, 2.6 g) - 1 hour, 6) acetone-epoxy resin 1:3 - 1 hour, 7) epoxy resin - 1 hour; complete the preparation of blocks as follows 8) when tissues have been oriented in epoxy resin in flat embedding molds, place molds in one evacuated vacuum desiccator 10 cm above a 2 cm layer of Drierite for 24 hours at room temperature, 9) raise temperature to 60 C and maintain for 3 days to cure resin.

Animals↗
PubMed1992

Glycidyloxy compounds used in epoxy resin systems: a toxicology review.

The glycidyloxy compounds constitute an important group of chemicals used extensively in the formulation of epoxy resin systems employed in coatings, electronics, structural composites, and adhesives. Although extensive toxicological data are available on glycidyloxy compounds, use and understanding of the data have been hampered by two major problems: (1) proper identification and complexity of the epoxy systems in question, and (2) absence of meaningful classification of epoxy materials. This paper provides a classification scheme with CAS numbers and reviews the mammalian toxicology of the most common glycidyloxy derivatives used in epoxy resin systems based on both published and proprietary information. Although the toxicity of many of the glycidyloxy compounds used in epoxy resin systems can be characterized as low, the diversity of compounds found within this group precludes broad generalizations for the class. This comprehensive account should facilitate a clearer understanding of the potential health effects and allow for easier comparison among compounds containing the glycidyloxy moiety.

Animals↗
PubMed1976

Sensitivity to epoxy resins and triethylenetetramine.

The present studies concerned 31 work sites in eight factories at which 422 persons were employed. In the course of seven years there were 126 cases of dermatitis, 99 of whom were patch-tested. Positive reactions to epoxy resin and/or to triethylenetetramine were found in 65.7% of the subjects. The aetiology of the other cases is discussed. Some of the patients who were positive to epoxy resin were tested with Bisphenol A and modified resins with blocked epoxy groups. The latency period of dermatitis and the localization were recorded, as well as the influence of the season and of certain working conditions on the occurrence of sensitization. Of the 80 patients who changed their occupation, there were relapses in 50 within one year. Relapses were more frequent in persons who continued to work with epoxy resins for more than three months after the appearance of dermatitis and in those simultaneously sensitive to allergens in the standard series.

Dermatitis, Contact↗
PubMed1979

Persistent photosensitivity following occupational exposure to epoxy resin.

Persistent photosensitivity developed in eight men following occupational exposure to hot epoxy resin fumes. The condition was limited to sites the resin contacted. Small doses of ultraviolet-A light (2 to 5 joules/sq cm) evoked abnormal reactions consisting of erythema, edema, and papules in the clinically involved skin. Positive photopatch tests to epoxy resin were observed in four subjects, and to 4, 4'-isopropylidenediphenol (Bisphenol A) in all. The photosensitivity is most probably due to photocontact allergy to 4,4'-isopropylidenediphenol or to a closely related chemical.

Adult↗
PubMed1978

Sensitization capacity of epoxy resin oligomers in the guinea pig.

Low molecular weight oligomers of an epoxy resin of bisphenol A diglycidyl ether type were isolated by gel permeation chromatography. The sensitizing capacity of these oligomers was assessed with the "guinea pig maximization test". The oligomer with the molecular weight of 340 sensitized 80% to 100% of the animals, but produced no cross reactions to the other oligomers. The MW 624 oligomer sensitized 56-60% of the animals and 30% of these showed cross reactions to the MW 340 oligomer. The MW 908 and MW 1192 oligomers elicited no reactions. It was shown that sensitization with epoxy resin mixtures of high average molecular weight depends mainly on the content of the MW 340 oligomer.

Administration, Topical↗
PubMed1992

Medium temperature epoxy resin for immunocytochemistry: Quetol 651 with water.

The addition of 1% water to the epoxy resin Quetol increased the labeling intensity of the sample. The significant decrease of the curing temperature of the epoxy resin may assist in preservation of antigens. Water may also reduce the cross-linkage of the resin allowing more antigen to be available to the antibodies. The modified Quetol resin is an option for use in immunocytochemistry studies.

Basidiomycota↗
PubMed1977

Epoxy resin based tissue substitutes.

A series of epoxy resin based tissue substitutes, simulating adipose tissue, bone, breast, lung, muscle and skin is described. Details of the physical radiation characteristics of the formulated systems are given, together with the manufacturing procedures. The versatility of the range of substitutes is discussed in terms of both investigated and projected applications in experimental radiation studies.

Adipose Tissue↗
PubMed1979

Penetration of protective gloves by epoxy resin.

A gas jointer developed dermatitis from epoxy resin of Bisphenol A type. This substance penetrates plastic and rubber gloves. The man was compelled to change his job. There is a need for new types of gloves which are impermeable. The wearing of the existing types of glove by those not sensitised may be worthwhile because it probably lessens the dose of allergen absorbed and hence lessens the incidence of sensitisation.

Adult↗
PubMed1978

Occupational allergic contact dermatitis to isophorone diamine (IPD) used as an epoxy resin hardener.

Three patients employed in the manufacture of plastic tennis rackets developed allergic contact dermatitis to isophorone diamine (IPD), an epoxy resin hardener, and concomitantly to epoxy resin. Patch tests were positive to IPD at 1, 2 and 5% in olive oil and to IPD at 1, 2 and 5% in ethanol. Investigations were conducted in control subjects to confirm the allergic nature of reactions. A review of the literature about IPD and related compounds is presented.

Adult↗
PubMed1977

Organometallic and organometalloid compounds as standards for microprobe analysis of epoxy resin embedded tissue.

X-ray microanalysis of phosphorus, transition elements and heavy metals in biological tissue is frequently carried out on thin sections of specimens embedded in epoxy resin. A logical choice for the quantitive microprobe analysis of these specimens is a standard, consisting of a homogenous solution of the elements of interest in the epoxy resin. Four kinds of compounds were found suitable for this purpose: (1) phenyl compounds containing group Vb elements, (2) cyclopentadienyl-derivatives, (3) a pentanedione derivative (acetylacetonate) and (4) complexes of metals with dialkyldithiocarbamates. In the latter case, the standard also contains sulphur. Standards for P, Sb (1) Mn, Fe (2) Ni (3) Cu, Zn, Cd, Hg, Pb, Bi (4) were prepared in Epon 812 or Spurr epoxy resin. The compounds were mixed with the resin (without accelerator) to which some propylene oxide may be added, and dissolved immediately or after short heating. The maximal concentration of metal was in the order of magnitude of several promilles to 1%. Solubility in the Spurr resin was better than in Epon 812. After addition of the accelerator, polymerization was carried out as usual. The compounds used are commercially availalbe at low cost or can be easily prepared.

Alkanes↗
PubMed1977

Asthma due to inhaled chemical agents--epoxy resin systems containing phthalic acid anhydride, trimellitic acid anhydride and triethylene tetramine.

Six workers with a diagnosis of occupational asthma and one with chronic bronchitis were examined for sensitivity to epoxy resin systems and certain of their components. In six cases the chemical agent responsible for their symptoms was identified by careful inhalation challenge testing, simulating their exposure at work and thus providing a precise aetiological diagnosis. In one worker asthma followed exposure to triethylene tetramine fume; four were sensitive to acid anhydrides, three to phthalic acid anhydride as a fume or powder and one to trimellitic anhydride. On worker thought to be sensitive to toluene di-isocyanate gave negative reactions to this and positive reactions to a phthalic acid anhydride epoxy resin and another thought to have asthma from acid anhydride fumes was found to be sensitive only to toluene di-isocyanate. Immediate, non-immediate or combined asthmatic reactions were elicited.

Adult↗
PubMedDate not supplied

Respiratory effects of occupational exposure to an epoxy resin system.

A standardized respiratory questionnaire and pulmonary function tests were used to examine thirty-four employees of a snow-ski manufacturing plant, including twenty-five workers who were exposed to an epoxy resin system containing the amine hardener 3-dimethylamino propylamine (3-DMAPA). Maximum expiratory flow-volume curves were obtained on Monday and Thursday, before and after each shift, and FVC, FEV1.0, MEF50%, and MEF25% were caculated. Environmental measurements of the total amine levels were found to range from 0.41 to 1.38 ppm. The group with the greatest exposure (0.55-1.38 ppm) showed significant decreases in lung function over Monday and over the week. Although all employees in this group showed decreases in pulmonary function, acute changes were greater in present cigarette smokers and in subjects who reported respiratory symptoms upon exposure to the epoxy resin system. There was no evidence of permanent loss of lung function in subjects with either the highest or longest exposure.

Adult↗