European journal of toxicology and environmental hygiene. Journal europeen de toxicologie最新文献

Diethylstilboestrol, an anabolist used per os or in sub-cutaneous implants in a number of countries, but not in France, on animals of the bovine species, is absorbed by plants when spread on alfafa cultures. As this product is eliminated to a great extent through the fecal matter, its presence in fertilisers constitutes a danger to the environment, in view of its toxicity, whether direct or transmitted. This is a further reason for its use to be banned.

Maize starch pasteurized by irradiation was fed to OFA rats (Sprague Dawley derived) in an uncooked form (irradiated at 300 krad.) and in a cooked form (irradiated at 300 and 600 krad.) at dietary level of 62%. A six month toxicity trial was performed with uncooked starch and a 24 month trial with cooked starch. At the same time a reproduction study was conducted, over 3 generations with 2 litters per generation, using both uncooked and cooked irradiated starch. The parent generation (Fo) was randomly selected from animals in the feeding study and after the production of the F1a and F1b generations they were returned to that study. Control groups corresponding to each form of starch were established. They were fed the same diet except that the starch was not irradiated. The results of the various investigations conducted during the study (behavior, growth, mortality, haematology, serum biochemistry, histopathology) did not reveal any toxicological effect due to treatment, nor any effect on reproduction. No significant differences were shown between treated and control group.

During last 7 years, 13 cases of acute ethylene glycol poisoning have been observed with 4 fatal outbreaks. All cases--except one--were accidental. Six patients had drunk a mixture of antifreeze in water as they were lost in a desert. A patient who had taken 970 ml of ethylene glycol survived. In one case, death was due to irreversible brain damage; two other fatalities occurred from cardiorespiratory distress. CNS involvement was noticed in 8 cases and acute renal failure-constantly controlled-occurred in 9 patients. Post mortem examination has shown bi-refringent calcium oxalate crystals in both kidney and brain. Specific treatment with ethanol has been performed in 3 cases with ingestion of large amounts of toxic who were seen before definitive renal lesions have occurred. Emphasis is placed in symptomatic treatment including gastric lavage, extrarenal epuration and conservative management.

The authors report on the observation of an epileptic woman who showed the clinical and electro-encephalographic symptoms of an overdose of barbiturates when undergoing treatment associating Depakine and Gardenal. Resumption of the treatment results in identical symptoms. The potentialisation of this association and the mechanism by which it acts are as yet unknown.

Lindane, in contact with cultured foetal chicken liver cells over a period of 40 hours, has a biphasic action on the lysosomal system of the cells. For the concentrations between 1 micronM and 25 micronM not affecting the cellular growth, the decrease of the acid phosphatase activity and the absence of any reaction in the Golgi saccules might indicate a reduction in the synthesis of the lysosomal enzyme. For the concentrations above 25 micronM slowing down cellular growth, acid phosphatase activity is partialrogeneous content and an increase in the relative acid phosphatase activity in the soluble extralysosomal fraction, for doses over 150 micronM, might indicate the development of the phenomenon of autophagocytosis.

Tryptic hydrolysis conditions of ricinotoxin were studied in order to produce not only digestion of this glycoprotein but also still toxic tryptic peptides. No hydrolysis was obtained without prior denaturation. The best conditions of denaturation were obtained with 0.2 M guanidine hydrochloride and, to a lower extent, by heat treatment at 90 degrees C during 6 minutes. The hydrolysates were fractionated on Sephadex G100 column. In each case highly toxic peptide fractions were obtained which showed, like native ricinotoxin, a strong inhibitory action on the in vitro protein synthesis ina cell-free eukaryotic system but were without any action on a prokaryotic cell-free system.

The authors report a toxicological study of bis (tributyltin oxide) (TBTO) given by inhalation (oily aerosol) to 105 Hartley albino guinea pigs. Doses vary from 1 mg to 0.1 mg of TBTO per liter of aerosol. Death occurs for doses of 0.2 mg per le more resistant than the male ones. The intoxication is marked by a period of ocular and nasal irritation followed by a short remission time, then death occurs after asphyxic convulsions. With doses less than 0.2 mg per liter of aerosol, we observe only an irritation without mortality after one hour intoxication. Seven days later the animals are alive. Because of its liposulibility, TBTO is present in the whole body, particularly in liver, kidney, lung, brain and heart. Histological study does not reveal any peculiar lesion of the examinated organs. Especially there is no specific alteration of the respiratory system. The merely observed trouble is a diffuse congestion.

Administered to rats by stomach tubing oxythioquinox (Morestan) toxicity is very strongly increased after solubilisation in olive oil. The oxythioquinox DL50, in this case, is 500 mg/kg although we can reach 2.8 g/kg in aqueous suspensions. When it is administered (1 g/kg) in aqueous suspension, the decrease in body weight is the same as these observed with a 5 fold lower dose in oil. Conversion rate feed and weight of differents organs decrease when animals are daily submitted to oxythioquinox in oil, during 16 days, compared with animals treated with an equivalent dose in aqueous suspension. Potentiation, in oil solutions, of the decrease of oxythioquinox intestinal transit, promoting its absorption, could explain the increase of oxythioquinox toxicity in oil solution.

The trace elements are surrounding factors which are able to act on the yield of benzo(a)pyrene hydroxylation reaction of the hepatic tissue. This action was studied for each element and for various concentrations. The action of these elements may occurred to arylhydrocarbon hydroxylase by activating or inhibiting it, to epoxyde hydrase or to glutathione S epoxydase, favouring or inhibiting the way epoxyde dihydrodiol, and finally to arylhydrocarbon hydroxylase induction. Our results, obtained in vitro on hepatic tissue with many metallic salts, showed that some trace elements may have a cocarcinogenic action.

Forty male guinea pigs were exposed to nitrogen dioxide in a concentration of 2 mg/m3, 8 hours daily for a period of 180 days. Forty male animals were used as a control group. The following changes were found in intoxicated animals: the decrease of total protein and seromucoid concentration in blood serum and the decrease of total protein, perchloric acid-soluble proteins, protein-bound hexosamines and sialic acids content, in liver tissue. Electrophoretic examination of the serum proteins showed the increase of alpha 1- and beta 2-globulins and the decrease of albumin concentration. Changes in the level of glycoproteins fractions and protein-bound carbohydrates in blood serum were described also. Estimation of enzymes activity showed the decrease of alanine and aspartate transaminase activity in blood serum caused by the strong decrease of the cytoplasmic fraction of these enzymes. However the simultaneous increase of the mitochondrial fraction of transaminases activity was observed. The decrease of the activity of choline esterase was found also. Similar changes of enzymes activity were found in liver tissue. Histopathological studies were done for the further clearing the influenze of nitrogen dioxide on serum and liver proteins concentration and enzymes activity. It was found that after long-term exposure to nitrogen dioxide the destruction processes may be observed in the liver. The possible mechanism of the nitrogen dioxide-induced damage of protein metabolism is discussed.