Artificial streams in the assessment of environmental hazard of chemicals

Artificial streams are dynamic mesocosms, simulating aquatic systems and rivers. They are useful to study ecotoxicity of chemicals and their effects on flora and fauna colonizing the streams or introduced into the channels. These artificial rivers can also be used to study the influence of ecological and hydrodynamic parameters, such as the kind of substrate of river and flow rate. Responses of the bivalve Unio tumidus to substrate type (silt, sand, and pebbles) and water flow rate (high and low) were investigated after 15 and 35 days in the channels, in order to optimize the experimental conditions for ecotoxicity study with methyl methacrylate (MMA). The toxicological effects of different concentrations of MMA on bivalves and on communities of invertebrates and diatoms were determined after several weeks of exposure at a high flow rate. Biomarkers responses measured in the digestive gland and the gills of U. tumidus were the activities of detoxification systems as early indicators of toxicity and lipid peroxidation as a marker of cytotoxicity. Effects of MMA resulted in a decrease in antioxidant activities. Disturbances in bivalves appeared at lower concentrations than in communities. This indicates sensitivity of the biomarkers studied, which are predictive indicators of ecotoxicity.

"Cyclamen Red" colors based on a macrocyclic anthocyanin in carnation flowers

The "cyclamen" red (or pink) colors in carnation flowers-cultivars Red Rox and eight others-are based on the presence of a new macrocyclic anthocyanin, pelargonidin 3,5-di-O-beta-glucoside(6' ', 6' "-malyl diester) identified by spectroscopic methods. The instability of the bridging malyl group with sugars in acidic medium readily causes the formation of the opened ring form, 3-O-(6' '-O-malylglucoside)-5-O-glucoside. The issue of cyclamen colors based in carnations on this original acylated pelargonidin derivative simulating those based on simpler cyanidin glycosides in Rosa cultivars is discussed using CIELAB colorimetric coordinates.

Comparative study of methods chosen by the Association Française de Normalisation (AFNOR) for evaluating sensitizing potential in the albino guinea-pig

An evaluation was made of the different protocols recommended by the Association Française de Normalisation (AFNOR) for assessing the sensitizing potential of chemicals in the guinea-pig. The methods studied were those of Magnusson & Kligman (J. invest. Derm. 1969, 52, 268), Maguire (J. Soc. cosmet. Chem. 1973, 24, 151), Maurer et al. (Agents & Actions 1975, 5, 174), Klecak et al. (J. Soc. cosmet. Chem. 1977, 28, 53), Dossou & Sicard (1984, to be published) and a hitherto unpublished method of Guillot, Gonnet, Clément & Brulos. Results obtained by each method were compared in tests on the allergenic reference substances dihydrocoumarin, p-phenylenediamine, formalin, penicillin G and benzocaine (ethoform) and on propylene glycol (negative control). The results showed that the number of animals sensitized often varies with the choice of experimental protocol, that inclusion of tests on a control substance is essential, and that while quantitative differences were found, the methods were qualitatively similar in their capacity to identify allergens in the guinea-pig.

Evaluation of the ocular-irritation potential of 56 compounds

The ocular irritancy of 56 chemicals was tested in the rabbit eye, with and without rinsing, using a procedure that complied with the main requirements of three protocols, namely those proposed by the Association Française de Normalisation (AFNOR) in 1982 and by the Organisation for Economic Co-operation and Development in 1979 for the testing of chemicals and that published by the French authorities (Journal Officiel 21 April 1971, p. 3862; ibid 5 June 1973, p. 3953) for the testing of cosmetics and toiletries. The results obtained were used to establish the extent to which the assessment of a chemical's irritation potential was affected by the differences between the three protocols in respect of the observation times prescribed, the inclusion and timing of rinsing, the number of animals used and the interpretation procedure. Conclusions were also drawn about the influence of the physical state and pH of a material on its potential irritancy and about the level of irritancy that necessitates the use of eye protection.

Evaluation of the cutaneous-irritation potential of 56 compounds

The primary cutaneous irritation of 56 chemicals was tested in the rabbit using three different procedures. The three protocols selected for the tests were the method published by the French authorities for the testing of cosmetics and toiletries (Journal Officiel 21 April 1973, p. 3862; ibid 5 June 1973, p. 3953) and the methods proposed for the testing of chemicals by the Association Française de Normalisation (AFNOR) and, in 1979, by the Organisation for Economic Co-operation and Development. The results of the three sets of tests were compared and the effects of differences in procedure and numbers of animals were studied, together with the possible relation between irritancy and the pH of the test material. It was concluded that the AFNOR protocol best met the requirements for such tests and that gloves should be worn for the handling of all substances classified as moderately or severely irritant on that scale.