[Effect of directed infrared radiation on the skin and eye of rabbits after acute and chronic exposure].

The establish a threshold dose, an acute experiment was carried out by 30 min. radiation of the rabbit's shaved head with all ranges of infrared, 200 W/m2, 350 W/m2 and 500 W/m2 intensities. Irradiation was prolonged up to 2 hrs. Having established the threshold dose, a chronic (5 months') experiment was carried out, irradiating 9 rabbits' skin (in 3 groups) with 350 W/m2 intensity in the range of all three bands. Similarly, tests on the eye transparent part were performed, irradiating only one eye, the other being handled as the control. The results show that the 350 W/m2 intensity of IR-A and IR-C radiation induces a slight erythema on rabbits' skin under long-lasting radiation, and under all radiation ranges no changes in the eye transparent part result at the 350 W/m2 intensity for the IR-A band and 200 W/m2 for the IR-C band. On the other hand, when irradiating the eye with the IR-B band at the 350 W/m2 intensity, slight infiltrations and defects of the eyeball cornea were found. Temporarily, the 350 W/m2 value for human skin was suggested as the TLV for the directional radiation intensity within IR-A and IR-B. On the other hand, for the eye transparent part the following TLVs have been suggested: for the IR-A band--250 W/m2, for the IR-B--150 W/m2, for the IR-C band--150 W/m2. Those values do not refer to laser radiation and do not guarantee the development of cataract under many-years' exposure.