72 JOURNAL OF THE SOCIETY OF COSMETIC CHEMISTS PAPER TESTS ENABLING THE EVALUATION OF SMALL QUANTITIES OF PERSPIRATION (PRussIAN BLUE TEST) A strip of Scotch tape is sprinkled with the following mixture (finely ground): Fe2(SO4)• anhydrous ......................... 35% K4(FeCN6) anhydrous .................................... 65% The test paper, light gray before application, becomes colored in contact with water. Very fine drops of sweat are thus detected, each spot repre- senting the lumen of a sweat gland. This test has the advantage over that of Minor's in that it does not necessitate the painting of the skin with iodine which could modify the terrain. The Prussian blue test paper is rapidly saturated and is not adequate for the evaluation of abun- dant sweating (3, 6) (Fig. 4). Scores: ! Figure 4.--Standard Scale, Prussian blue test paper. PAPER TEST FOR HANDS AND FEET We have elaborated a test paper which permits the evaluation of abun- dant sweat secretion. A Whatman filter paper is impregnated with a 1 per cent bromophenol blue solution in anhydrous ether. In the absence of humidity, this paper becomes yellow by the action of water it changes to dark blue. Our principal objective in elaborating this test was to find a method permitting the evaluation of plantar and palmar sweating (5, 7) (Figs. 2 and 3). STUDY OF THE ACTION OF VARIOUS DRUGS ON THE SWEAT G•,AND (6, 8) A series of d•ugs influencing the autonomic nervous system were in- troduced in the skin by means of iontophoresis. By applying the Prussian blue paper tests at regular intervals on the treated site, the duration of action, and intensity of effect of a drug can be estimated (see Table 1). Drugs which inhibit sweating by their action on the autonomic nervous

STUDIES ON PERSPIRATION 73 TABLE 1--DURATION OF LOCAL PERSPIRATION INDUCED BY A FEW PARASYMPATHICOMIMETIO DRUGS Drug Dose Average Time Acetylcholine 2.10 -6 Mole 30 min. Pilocarpine " 2 hours 40 min. Mecholyl " 12 " Dilvasene " 36 " Doryl " 47 " system can be examined in the following manner. An iontophoresis of the drug to be examined is made on a large surface of skin, then at regular intervals pilocarpine is introduced in order to induce perspiration. By means of the Prussian blue paper test subsequently applied, it can be noted whether there is an inhibition or a decrease of local perspiration (see Table 2). TABLE 2--DURATION OF ANTISECRETORY ACTION OF A FEW PARASYMPATHICOLYTIC DRUGS Drug Dose Total Inhibition of Local Perspiration (Average Time) Prantal 2.10-6 Mole/9 cm. 2 Probanthine .... Antrenyl .... Attopine .... Scopolamine .... 15 rainß 2 hours 12 " 19 " 30 " To evaluate antiperspirants acting by local application as, for example, aluminum salts, the following procedure is carried out. The solution to be examined is applied twice a day for three days on the arm, then on the fourth day a local perspiration is induced by iontophoresis of pilocarpine on the treated site and on a symmetrical site as control. The Prussian blue test is applied and the intensity of color of both papers is compared. The same procedure is followed for the axilla, palm of the hand and sole of the foot, but the Ping-pong test and the bromophenol blue TABI, E 3 Reducing or Inhib- Number iting Effect (on Con- Wetting of Perspiration Induced centr. pH Agent Cases by Pilocarpine) AICl, Mol. 1.8-2 AI(NO,), Mol. 2.6 A12(SO4), Mol. 1.8-2 Al-acetotartrate 10% 3 MgCI.. Mol. 1.8-2 Phosphotungstic acid Satur. 0.8-1 Sulfosalicylic acid 10% 0.8-1 Tannic acid 10% 2.7-3 1% Triton X 100 33 Good id. 5 Good id. 6 None id. 5 Bad id. 8 Middle 6 None ß . . 1% Triton X 100 4 None 0.5% Aerosol OT 3 None