ASTM E2613-14. Standard Test Method for Determining Fungus-Eliminating Effectiveness of Hygienic Handwash and Handrub Agents Using Fingerpads of Adults.
Test accredited by ENAC (Spanish National Accreditation Entitity).
Test with the certificate of Good Laboratory Practices (GLPs).
This test method is designed to evaluate the ability to reduce the levels of contamination by fungi in the hands, either by hygienic hand washing or by hand friction, placing a fungal suspension test on the fingertips of adults for simulate hand contamination with transient fungal microflora. The dry inoculum located on the fingertips is treated with the test and control solutions (water with a standard hardness level). The test uses contamination of the hands of at least three adult subjects, in duplicate for each combination of test substance to be analyzed. Subjects will refrain from using any product containing antimicrobial agents for at least one week before the test, providing them with a personal grooming kit, without antimicrobial products, for exclusive use during the test. The hands of the three subjects will be washed and contaminated with some of the following test organisms: Candida albicans, Aspergillus niger (Syn. Aspergillus brasiliensis).
The assay allows the incorporation of an initial control, control of viability of fungi remaining after the inoculum has been allowed to dry, a control of fungi eliminated after treatment with a reference solution and up to four replicates to evaluate the efficacy of elimination of fungi of the product subjected to the test. In this way, the results obtained are compared with a reference product or a control and the results obtained from the product under evaluation, taking into account the fungal viability after drying, which will be used as a baseline to determine the degree of fungal elimination after treatment. The exposure time of the test substance must be a time representative of the actual conditions of use, for at least 10 seconds and no more than 30 seconds, with a maximum of 10 complete inversions of the vial over the fingertip. In case of viscous formulations, the vial will be inverted and kept in contact with the contaminated areas for the desired contact time, no investments being made and in case the test method needs to simulate a post-treatment handshift, The fingertip will be exposed to 1 mL of hard water for 5 to 10 seconds before the fungal elution. The test may or may not use an interfering substance, consisting of a solution of one or more organic compounds and / or inorganic substances, added to the fungal suspension to simulate the presence of body secretions, excretions or other foreign substances.
The organisms remaining in the fingertips are eluted and the eluate is assayed to detect the CFUs of viable fungi. To consider the product as a fungicide, a logarithmic reduction of 4 must be demonstrated in the viability titer of the test organism, a reduction evaluated by the Wilcoxon statistical method. The client must choose a test concentration, a contact time between 10 and 30 seconds, whether or not it is desired to incorporate interfering substance in the suspension of the organism and if the test method needs to simulate a post-treatment handswash, exposing the fingertip to 1 mL of hard water for 5-10 seconds before fungal elution. The applicant for the test must record these requirements on the test submission form.