SUNSCREEN TESTING METHODS 143 Appendix 1 Example of One SPF Calculation For Product C Wavelength EE(X) x I(X)' Abs(X) 2 T(X)' EE(X) x I(X) x T(X) 320 .0180 .45 .355 .0064 315 .0839 .(06 .219 .0184 310 .1864 .72 .191 .0355 305 .3278 .78 .1(06 .0544 300 .2874 .75 .178 .0511 295 .0817 .(06 .219 .0179 290 .0150 .57 .269 .0040 Z = 1.0 Z = .1877 'EE(X) x I(X) See reference #1 and text, supra 2Abs(X) = Absorbance of product-treated skin minus absorbance of untreated skin at each wavelength in- terval = absorbance of product 'T(X) = 10 -'ø Abs(X)

j. Soc. Cosmet. Chem., 31,145-151 (May/June 1980) The cost and utility of several microbial genetic toxicology tests JOHN R. ROHEIM and JOHN E. HEINZE, Armour and Company, Armour Research Center, Scottsdale, AZ 85260 Received May 7, 1979. Presented at Annual Scientific Seminar, Society of Cosmetic Chemists, May 1979, Dallas, Texas. Synopsis In order to gain experience with genetic toxicology testing and to be able to comment on any proposed governmental regulations, we have instituted a program to evaluate several genetic toxicology assays. The complete program consists of a computerized literature search and an evaluation process for short-term in vitro assays. Using this program, we have determined the ACCURACY, REPRODUCIBILITY, COST, and TIME requirements of SEVERAL MICROBIAL GENETIC TOXICOLOGY TESTS. INTRODUCTION Genetic toxicology testing has been the subject of recent discussions by the Society of Cosmetic Chemists (1,2,3). These tests are gaining wider acceptance and may at some future date be required for safety evaluation (4,5). Therefore, a program has been initiated to evaluate a variety of genetic toxicology tests. This report describes the process of evaluation used and the investigation of three different types of microbial tests. Programs similar in nature are in progress in other laboratories (6,7). GENETIC TOXICOLOGY EVALUATION PROGRAM The genetic toxicology program consists of a two-part evaluation process. The first part makes use of computerized literature search techniques (8) to efficiently obtain current scientific literature on test methods and controls to be used in the evaluation. The second part consists of a comparative evaluation of several tests using reference compounds. Based on the results of the literature search, three types of microbial tests were chosen for further consideration: bacterial mutation assays, bacterial DNA repair tests, and tests using eukaryotic microorganisms, i.e., yeast. BACTERIAL MUTATION ASSAYS A number of tests using bacteria have been developed to measure the mutagenic potential of a chemical, i.e., the ability of the chemical to produce forward or reverse 145