[Acute toxic effects of trimethyl and triethyl phosphites]

The studies on toxic properties of trimethyl and triethyl phosphities involved: determination of acute general toxic effect on white rats following intragastric and intraperitoneal administration of these compounds, based on DL50 test, determination of damaging effect direction, by histopathological examination of animals' internal organs, determination of intensity of primarily irritating action on the skin, eye and conjunctiva, as well as sensitizing effect on guinea-pigs. DL50 value for trimethyl phosphite following intragastric administration was found to be 2.45 g/kg and following intraperitoneal administration--2.25 g/kg; for triethyl phosphite these values were: 4.00 g/kg after intragastric administration and 1.50 g/kg after intraperitoneal administration, respectively. In local action both phosphites mildly irritate the skin, eye and conjunctiva. A weak sensitizing effect of triethyl phosphite was found. Trimethyl and triethyl phosphites have general toxic effects. A particular direction of their action is demonstrated by acroparalysis. Apart from general action they were found to show systemic action and induce parenchymatous degeneration of the liver and kidneys, whatever route of administration. Administered intragastrically, they result in mucosa necrosis, ulceration and fibrino-purulent exudate, exfoliating the mucosa.