Sensitisation tests

European Centre for Ecotoxicology and Toxicology of Chemicals, Skin Sensitisation Testing, Mono. No. 14, Brussels, 1990. 

Organisation of Economic Cooperation and Development, Skin Sensitisation Testing Methodological Considerations, Tech. Rep. No. 78, Paris, 1999. 

ECETOC. 2000. Skin sensitisation testing for the purpose of hazard identification and risk assessment. ECETOC Monograph No. 29. Brussels ECETOC. 

Ashikaga T, Sakaguchi H, Sono S, Kosaka N, Ishikawa M, Nukada Y, Miyazawa M, Ito Y, Nishiyama M, Itagaki H (2010) A comparative evaluation of in vitro skin sensitisation tests the human cell-line activation test (h-CLAT) versus the local lymph node assay (LLNA). ATLA 38 275-284... 

ECVAM (2015a) https //eurl-ecvam.jrc.ec.europa.eu/eurl-ecvam-recommendations/eurl-ecvam-recommendation-on-the-human-cell-line-activation-test-h-clat-for-skin-sensitisation-testing (accessed on October 14, 2015). 

Organisation for Economic Cooperation and Development (1993) Skin sensitisation test guideline 406 Robinson MK, Nusair TL, Fletcher ER, Ritz HL (1990) A review of the Buehler guinea pig skin sensitisation test and its use in a risk assessment process for human skin sensitization. Toxicology 61 91-107... 

In vitro methods for predictive skin sensitisation testing are not presently available for routine use (De Silva et al. 1996). 

De Silva O, Basketter DA, Barratt MD, et al. (1996) Alternative methods for skin sensitisation testing. Report and recommendations of ECVAM workshop 19. Altern Lab Anim... 

In the last 50 years, skin sensitisation potential assessment has been of paramount importance for ensuring the safety of cosmetic products. Different human sensitisation tests, such as Schwartz-Peck test (Schwartz, 1969), human repeated insult patch tests (Marzulli and Maibach, 1973 Griffith and Buehler, 1976) and human maximisation test (Kligman and Epstein, 1975), have been used but standardised test guideUnes are not available and the tests have not undergone an official validation process. 

Health and Safety Factors. Results of acute oral toxicity studies of 2-pyrrohdinone on white rats and guinea pigs show the LD q to be 6.5 ml,/kg. Skin patch tests on 200 human subjects indicate that 2-pyrrohdinone is a skin kritant, but there is no indication of sensitising action. It is a mild eye irritant (79). 

France, W. D. and Greene, N. D., Some Effects of Ex(>erimental Procedures on Controlled Potential Corrosion Tests of Sensitised Austenitic Stainless Steel , Corros. Sci., 10,379(1970) Tedmon, C. S. (Jr.), Intergranular Corrosion of Austenitic Stainless Steel , J. Electrochem. Soc., 118, 192(1971)... 

Fig. 3.21 Temperature-time-sensitisation diagrams for three austenitic Cr-Ni steels solution treated at 1 0S0°C. The curves enclose the treatments causing susceptibility to intercrystalline corrosion in a boiling CUSO4 -F H2SO4 test reagent...

Fig. 8.34 Intergranular cracking of sensitised type 316 stainless steel tested in air-saturated water at 7S°C containing 5 ppm chloride...

Fig. 8.35 Reduction in area versus applied potential for 316 stainless steel, in 5 ppm chloride content water at 250°C. Horizontal arrows indicate RA% for tests in argon gas open-annealed, filled-sensitised. Vertical downward pointing arrows on the annealed curve indicate cracking-non-cracking boundaries. Full downward pointing arrow on the sensitised curve indicates commencement of cracking. Open upward pointing arrow on the sensitised curve indicates transition from transgranular to intergranular cracking...

The strains needed to initiate cracks in both the annealed and the sensitised materials were obtained using tapered slow-strain-rate specimens and the data are given in Fig. 8.36. As can be seen, there is little temperature dependence of the strain needed to initiate cracks in sensitised material whereas the annealed material was most susceptible to cracking at about 250°C. These results indicate the complicated response of Type 316 stainless steel to applied potential and demonstrate that, even though environmentally-assisted cracking may be generated by severe test methods, in this case the slow-strain-rate test, the results obtained must be used with care. For instance, the cracking of the annealed material at low potentials... 

Fig. 8.36 Minimum strains for initiating stress-corrosion cracks in annealed and in sensitised 316 during slow strain rate tests in S ppm chloride content water...

With some materials, there are specific heat treatments that are known to reproduce the worst effects of the heat of welding. It is recommended, therefore, that in tests made to qualify a material for a particular service environment, in addition to the exposure of welded test specimens in order to observe effects of welding heat, specimens should be included that have been given a controlled abusive or sensitising heat treatment. As an illustration, austenitic stainless steels may be held at 650-700° forO-5-1 h, followed by testing for susceptibility to intercystalline attack as in ISO 3651-1 or -2 1976. 

Brown has pointed out that Du Pont use evaluation tests for (a-) as-received unstabilised alloys containing more than 0-03% C to check the effectiveness of the final heat treatment and (b) stabilised or special low-carbon grades after a sensitising treatment (1 h at 677°C) to determine whether susceptibility might develop during a subsequent welding operation. 

Fig. 19.15 Schematic representation of range of corrosion potentials expected from various chemical tests for sensitisation in relation to the anodic dissolution kinetics of the matrix (Fe-l8Cr-IONi stainless steel) and grain boundary alloy (assumed to be Fe-lOCr-lONi) owing to depletion of Cr by precipitation of Cr carbides of a sensitised steel in a hot reducing acid (after Cowan and Tedmon )...

Accumulation of corrosion products does not stimulate attack so that several specimens may be tested in the same solution, but additional Fe2(S04)j may have to be added (or the solution changed) if there is considerable attack on severely sensitised specimens, as is indicated by a colour change of the solution from brown to dark green. 

The redox potential of the solution is that of the Fe /Fe equilibrium and lies within the range 0-80-0-85 V (v. S.H.E.). The high weight loss of susceptible alloys is due to undermining and grain dislodgement at the sensitised zones, which occurs at about twice the rate of that in the Huey test. Another difference is that whereas in the Huey test corrosion products... 

In conclusion it must be emphasised again that all the tests used are accelerated tests and only provide information on susceptibility to intergranular attack under the precise test conditions prevailing. They are quality control tests that may be used to demonstrate either that heat treatment has been carried out adequately or that a steel will withstand the test for a certain sensitising heat treatment. 

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