300 JOURNAL OF THE SOCIETY OF COSMETIC CHEMISTS SPM. The longer the total time of the injection, the greater the total amount of SPM solution that could be injected. It is believed that the animals died from anoxia because of the increased respiratory effort and the very dark color of the blood which could not be accounted for by any fall in the blood pressure. At death, a complete autopsy was made and sections of the liver and kidneys were examined microscopi- cally. There was practically no glycogen storage in the centers of the liver lobules but considerable deposits were evident at the pe- riphery. The kidneys and other organs were negative. On gross inspection only a generalized vasodi- lation and cyanotic tinge were evi- dent in the viscera. 3. Intravenously administered SPM to rabbits: Sodium perborate monohydrate was injected intra- venously into unanesthetized rab- bits, the data being shown in the appended Table 2. The release this mechanism because the injec- tion of doses of sodium metaborate much larger than would result from lethal doses of SPM proved in- nocuous. The LD50 of SPM cal- culated according to the method of Reed and Muench (6) lies at 78 mg. per kilo. Sodium metaborate, either as "spent" perborate or as the pure chemical, was given intravenously in doses up to 300 mg. per kilo without toxic effects. Rabbits that did not die during or within 15 minutes following the injection of the SPM, survived indefi- nitely. Serial autopsies were per- formed on such animals from a few hours to several days after the in- jection of either SPM or of sodium metaborate. There were no dis- tinctive gross or microscopic patho- logical findings. The liver distur- bance which was found in rats after oral doses was not so evident in the rabbits despite the intra- venous route of administration. TABLE 2--ToxICITY 01• SODIUM PEKBORATE MOIVOHYDRATE INTRAVENOUS ADMINISTRATION TO RABBITS Weight Time to Dose,* Range, Inject, Injected Died Died,j' Mg. X Kg. Kg. Min. No. No. % 22 3.6 1.5 1 0 0 50-56 3.2-3.4 2.5-4.5 3 1 6 60-68 2.1-4.5 2.54.5 11 3 22 70-80 2.9-4.8 3.0-5.5 9 3 54 * 2.0% solution. t Method of Reed and Muench (6) LD5078 mg. X Kg. of hydrogen peroxide caused the oxidative formation of methemo- globin which resulted in deep cyano- sis and asphyxial death. It is believed that death was due to Microscopic examination of the liver revealed some granularity of the liver cells but only slightly greater in the SPM-injected ani- mals than in the sodium metaborate

ON THE TOXICITY OF SODIUM PERBORATE 301 or control animals. In the tissues of the animals that died during or imme- diately following the SPM injection, there was found capillary dilatation and vascular congestion similar to that seen in animals dying in shock. 4. Oral administration to rabbits: Attempts were made to determine the toxicity of SPM given orally to rabbits. No data could be obtained because of the bloated condition of the stomach result- ing from decomposition of the SPM. Evi- dently, cardiospasm prevented regurgita- tion of the oxygen and the animals died in shock. The stomach of one rabbit ruptured due to the gas pressure, the animal dying soon thereafter. 5. The irritant properties of solutions of SPM: These were determined on the eyes of rabbits after the method of Hirschhorn and Mulinos (7). This method conforms to actual practice, wherein the SPM solution used as cold wave neutralizer may run into the eyes of the subject by virtue of careless ap- plication. The actual concentration, 0.87 per cent of neutralizer was used, corre- sponding to a 0.7 per cent solution of sodium perborate. Because of the lack of irritation of this solution, solutions double and quadruple this strength were used in order to determine the effective strength causing irritation. The results are summarized in Table 3. No miosis resulted. The temporary blepharospasm lasted from 10 to 15 min- utes and was only slightly greater than from the control instillation of' saline. Recovery was complete from the slight irritation shown in Table 3, no after- effects being evident during the week following the instillation.