Pulmonary toxicity of aerosolized oil-formulated fenitrothion in rats.

To evaluate the potential risk of pulmonary damage due to aerial spraying of the insecticide fenitrothion, rat lungs were examined under light and electron microscopy at 3, 7, 21, and 60 days after exposure. Rats were exposed by a "nose-only" apparatus for 1 hr to 2 or 500 mg/m3 of aerosolized fenitrothion (15%) mixed with solvent Cyclosol 63 (35%) and diluent oil 585 (50%). Aerosol size particles were monitored by a light scattering apparatus. Only minor modifications of lung alveolar tissues were observed after exposure to the high concentration. At 3 days, discrete foci of mild inflammation were detected, including interstitial edema, cellular infiltration, and increased number of alveolar macrophages. At 7 days, signs of irritation were diminished while at 21 and 60 days alveolar tissues were essentially normal. Exposure to lower concentration induced more limited changes at 3 days; no modifications were seen at later periods. It is concluded that a single exposure to this fenitrothion mixture at 500 mg/m3 presents no serious hazard of pulmonary toxicity.

[Secretion of two different monokines. Effect of TPA and silica]. / Sécrétion de deux monokines différentes. Influence du TPA et de la silice.

IL 1 can be released from P388D1 cells; addition of TPA increases the level of mitogenic activity but an analysis of the phenomenon shows that this increase is not due to a higher level of IL1 secretion but rather to a comitogenic activity that develops upon incubation of TPA in foetal Calf serum containing media. In contrast, addition of silica enhances the release of IL1. Murine peritoneal macrophages produce a monokine (FRM) with macrophage replacing activity for the in vitro antibody production against SRBC. The presence of silica induces supernatants which in addition increase the proliferation of thymocytes. Chromatography on ultrogel AcA54 shows that the activity obtained from resident cells is due to FRM (M.W. 35000) whereas IL1 (M.W. 15000) is released upon incubation with silica. The same effect has been observed with Rats: IL1 is released instead of FRM when silica is added to peritoneal macrophages.

Retention of pollen grains in human lung.

The possibility of the penetration of pollen grains into the tracheobronchial tree is still a controversial question. To investigate this phenomenon further two different approaches were conducted: 1) Acetolysis (acidic degradation of organic constituents) of mucosal samples from different levels of the pig respiratory tract showed that specific (plane tree) inhaled pollens were not found beyond the main bronchi. 2) In contrast, a noticeable number of pollens were present in acetolyzed residues of lung surgical samples; this was shown to be due to contamination. In the first approach this problem was avoided; however, the analysis of surgical samples could be a valuable technique if suitable controls were included.

[Three new cases of pulmonary fibrosis in finishers of tools reinforced with tungsten carbide (author's transl)]. / A propos de trois nouveaux cas de fibrose pulmonaire chez des affûteurs d'outils renforcés au carbure de tungsténe.

On the basis of three new cases of pulmonary fibrosis due to heavy metals, the authors review the various clinical, radiological and respiratory function test criteria which lead to the diagnosis of this type of occupational fibrosis. This is an uncommon disease (21 cases published up to the present in France), insufficiently known, but with significant and sometimes severe risks. On July 19th 1980, the disease was added to the list of occupational diseases with No 70.

[Silicosis with a rapid and pseudo-tumoral course occurring in a case of pre-existant progressive and treated pulmonary sarcoidosis in a miner little exposed to silicosis risk : sarcoido-silicosis (author's transl)]. / Silicose d'évolution rapide et pseudo-tumorale greffée sur une sarcoïdose pulmonaire évolutive et traitée chez un mineur peu exposé au risque silicotique : la sarcoïdo-silicose.

The authors report the case of a miner suffering from pulmonary and nodal sarcoidosis treated with corticosteroids where during a multivisceral exacerbation with iritis and erythema nodosum there developed rapidly progressive pseudo-tumoral silicosis. Pulmonary and nodal biopsies by thoracotomy revealed silicotic masses in the upper lobe, penetrated and bordered by sarcoid granulomas. In the middle lobe and hilar nodes, only sarcoid process was present. This new entity, sarcoido-silicosis, follows its own course, insensitive to corticosteroids. By virtue of its immune status, sarcoidosis favourised the rapid development of silicosis, the latter being unexpected since exposure had been moderate. Deficiency in the elimination of silica particles from the lungs is discussed. A trial of treatment using aluminium hydroxy-allantoinate did not lead to any conclusion.

Action of intensive cigarette smoke inhalations on the rat lung. Role of particulate and gaseous cofactors.

The action of high doses of cigarette smoke alone or combined with coal dust or acrolein was investigated in noninbred Sprague-Dawley rats. Inhalation occurred up to six sessions per day (Hamburg machine), the animals being subjected to a treatment with oxygen after each inhalation session to reduce the carbon monoxide level in the blood. The amount of tar found in the lungs depended on the number of inhalation sessions per day rather than on the total number of inhalations. Smoke inhalation caused emphysematous lesions, the extent of which depended on the total dose of smoke inhaled. No lung tumors were observed. Only a hyperplasia of the alveolar lining involving type II alveolar cells and, at a later stage, areas of metaplasia generally limited to the bronchial area were found. The association of coal dust with cigarette smoke did not alter the specific effects of smoke and resulted in effects peculiar to the action of dust: alveolitis of the macrophage type, fibrosis of the reticulin type, limited hyperplasia, and ciliated metaplasia. When smoke was combined with acrolein, the effects due to smoke were not appreciably altered.

Experimental study of pulmonary emphysema in rats exposed to coal dust and papain: effects on the infrastructure and the cell dynamics.

Experimental lesions of emphysema were produced in SPF rats after laryngotracheal injection of papain and coal dust. The infrastructural changes were investigated a different intervals. The lesions observed are progressive, characterized by atrophy and ruptures of the interalveolar septa, and the disappearance of pneumocytes II. Passage through the septa of mineral particles is enhanced and total dust clearance seems to be increased. The results are discussed in the light of alveolar clearance studies using Fe-59 and surface tension measurements on pulmonary washings.

[Behaviour of asbestos fibres in the respiratory system as revealed by animal experiments (author's transl)]. / Etude expérimentale du devenir des fibres d'amiante dans l'appareil respiratoire.

By comparing the evolution of chrysotile and amosite fibres in rat lungs, more rapid clearance was found in the case of chrysotile. The rate of chrysotile clearance is strongly influenced by the size factor. The two varieties of asbestos also differ in their chemical behaviour in the lung. The evolution of chrysotile fibers in vivo is characterized by progressive decrease in magnesium content, while silicium retained in the fibre skeleton is practically not eliminated. Transport of fibers from the lungs to the lymph-nodes, the parietal pleura and the diaphragm also differs with the two asbestos varieties. From fibre counts with the electron microscope, chrysotile was more rapidly eliminated from the lungs than amosite. The concentration is higher with amosite in the lymph-nodes, and with chrysotile in the diaphragm. This last result confirms observations made on human lungs.

[Factors influencing the elimination of the migration of inhaled mineral particles (author's transl)]. / Facteurs influençant l'épuration et la migration des particules minérales inhalées.

The reaction of the body to inhaled mineral dust brings into play physiological and pathological mechanisms in which immunological processes may be involved. An analysis is made of phagocytosis by alveolar macrophages, of the transport of dust to the lymphatic system, of dust aggravation in lymphoid tissues on lymph glands and of the resulting lesions. The part played by dust in immunological disturbances is put forward in the cases of tubercular infections, experimental arthritis and tumors.

[Are rat alveolar macrophages capable of phagocytizing pollen grains?]. / Les macrophages alvéolaires de rat peuvent-ils phagocyter les grains de pollen?

Plane-tree pollen grains were incubated in vitro with alveolar macrophages from inbred Rats, and the possibility of phagocytosis was investigated. No phagocytosis was observed even after 48 hrs incubation. But alveolar cells were bound to pollen grains generally at the apertures. This binding did not require the Fc receptor on the macrophage membrane.

[Dissolution of the pulmonary collagen of the normal rat by repeated pepsin action]. / Etude de la dissolution du collagène polmonaire de Rat normal par des attaques pepsiques répétées.

A non-denaturating method of extracting collagen from Rat lungs was developed. It consists in dissolving the collagen by repeated action of pepsin. Depending on the age of the animal, efficiency values between 50 and 90% are obtained.

[Asbestos fibers in alcoholic beverages. Contaminating role of filtration material]. / Recherche de fibres d'amiante dans quelques boissons alcoolisées. Rôle contaminant des matériaux de filtration.

The presence of asbestos fibres was searched for in samples of wines, brandies and spirits which had or had not been filtered through asbestos filters. The materials examined were filtered on a micropore membrane that was then handled for electron microscope examination. Asbestos fibres were identified by their morphology and X-ray diffraction pattern and in certain cases additionally by punctual ultimate analysis (Edax). The presence of chrysotile fibres, generally separate but sometimes in clumps, was found in all the drinks which had been filtered through asbestos filters, while the non filtered drinks contained only a small concentration that was approximately equal to the one found in water analysed elsewhere. Only two samples of liquor, raw or filtered through a filter not containing asbestos, were absolutely free from fibres. On the other hand, the use of mixed filters of asbestos and cellulose resulted in only contamination by such mineral fibres.