State Institution "Institute for Occupational Health of the National Academy of Medical Sciences of Ukraine", Kyiv
Introduction. Phosphorous acid is a widely known product, used for chemical synthesis as a reducer in production of phosphites in the processes of water preparation, production of pesticides and agrochemicals. In spite of the so wide use, hygienic regulation of phosphorous acid in the working zone air has not yet been developed. A need to regulate phosphorous acid in Ukraine appeared due to its use in the technological process of domestic fungicide preparations as a water solution as well as a reagent for receiving a salt – aluminum phosphite.
Purpose of the study. To substantiate a Tentative Safety Exposure Level (TSEL) of phosphorous acid for the working zone air in regulation of its practical use in the technological process in production of chemical means of plant protection.
Materials and methods. The substantiation of TSEL for phosphorous acid in the working zone air was made, using a national method traditional for regulation – calculation equations (models), based on the known experimentally established toxicometric parameters with account of chemical structure of a substance, class of danger, physico-chemical properties, character of a biological action, etc.
Results. Based on the analysis of the literature data, a conclusion has been made, that according to parameters of toxicometry, phosphorous acid can be referred to substances of Class 2 of danger –"highly dangerous" with high irritation effect on the skin and mucous membrane of eyes. The main index in the toxicological assessment of phosphorous acid is its nonselective irritation effect: its parameter (Limir.) was used for calculation of the hygienic standard – TSEL for the working zone air.
Conclusion. The recommended value of TSEL for phosphorous acid in the working zone air is 0,1 мg/м3 (2 Class of danger, aerosol) with a mark "special protection of the skin and eyes is needed").
Key words: phosphorous acid, analogues of phosphorous acid, toxicological characteristics, priorities of toxic effect of phosphorous acid, TSEL for the working zone air