Decompoisition of toxic and environmentally hazardous 2,3,7,8-tetra-chlorodibenzo-p-dioxin by gamma irradiation

Summary The decomposition of the toxic and environmentally hazardous 2378-TCDD by gamma irradiation was studied and successfully used to decontaminatge laboratory wastes containing small quantities of this chemically and biological stable compound. The method makes use of gamma irradiation from a commercial⁶⁰cobalt facility at high dose levels (100 kGy) to break down the compound into notoxic products. Irradiation also decomposed 2378-TCDD in contaminated soil from the Seveso accident.     

Degradation of 2,3,7,8-tetrachlorodibenzo-p-dioxin in organic solvents by gamma ray irradiation

Summary The effect of gamma ray irradiation on 2,3,7,8 tetrachlorodibenzo-p-dioxin (TCDD) dissolved in organic solvents is described; TCDD is degradated with the loss of 1 or more chlorine atoms.Gammatom, Via 24 Maggio, 14, I-22070 Guanzate, Como, Italy.     

Effects of gamma irradiation on dermal equivalents in vitro

Summary Dermal equivalents (DE), collagen lattices, were produced in vitro and used as a model for studying the possible role of a pure population of fibroblasts in post-radiotherapeutic dermal fibrosis. Single doses of gamma irradiation induced a partial inhibition of the collagen lattice retraction and of protein synthesis. The collagen production was less inhibited than was synthesis of non-collagen protein, which resulted in an increase of the relative amount of collagen synthesized by irradiated fibroblasts. These data suggest that gamma irradiation might be able to select some fibroblast clones able to produce increasing amounts of collagen. This selection process could be involved in the development of tissue fibrosis after therapeutic radiation.     

Effects of gamma irradiation on dermal equivalents in vitro

Dermal equivalents (DE), collagen lattices, were produced in vitro and used as a model for studying the possible role of a pure population of fibroblasts in post-radiotherapeutic dermal fibrosis. Single doses of gamma irradiation induced a partial inhibition of the collagen lattice retraction and of protein synthesis. The collagen production was less inhibited than was synthesis of non-collagen protein, which resulted in an increase of the relative amount of collagen synthesized by irradiated fibroblasts. These data suggest that gamma irradiation might be able to select some fibroblast clones able to produce increasing amounts of collagen. This selection process could be involved in the development of tissue fibrosis after therapeutic radiation.     

Lymphocyte subpopulations in adjuvant arthritis of rats. Effects of corticoids and gamma irradiation]

Experimental model of human chronic inflammatory arthritis, adjuvant arthritis may be induced only in several strains of inbred Rats: it is well developed in LEW and practically absent in WAG. After adjuvant injection, the PHA-stimulable lymphocytes subpopulation quite disappears from the blood, if polyarthritis is well developed. These cells are probably capted in the tissues implicated in immunological conflict. On the contrary, the ConA-stimulable subpopulation is enhanced in both strains after adjuvant injection, earlier and more intense in WAG than in LEW and that phenomenon is probably linked to a stimulation of suppressor T lymphocytes. Treatment with prednisone or gamma rays inhibits partially and delays the appearance of arthritis in LEW, acting essentially on ConA-stimulable subpopulation.     

Accumulation of 2,3,7,8-tetrachlorodibenzo-p-dioxin from soil and nutrient solution by bean and maize plants

Summary Maize and bean plants grown on soil polluted with³H-2,3,7,8-tetrachlorodibenzo-p-dioxin (³H-TCDD) accumulated the toxin in the aerial parts progressively with the time and with the soil contamination. Plants in hydroponic solution polluted with³H-TCDD accumulated the toxin in the aerial parts in the light and not in the dark; the concentration of TCDD accumulated was not proportional to the surface area of plant organs; the distribution of³H-TCDD in the leaves suggested that TCDD was translocated through the vessels to the aerial parts by the transpiration stream.     

Time-course of changes in lipofuscin-like pigments in rat liver homogenate and mitochondria after whole body gamma irradiation

Summary An increased level of lipofuscin-like pigments in rat liver homogenate was observed 18 days after whole body gamma irradiation, while in mitochondria they decreased below the control value.     

Ozone production by a corona-type loudspeaker and its toxic effects in mice

Résumé L'ionophone est un émetteur sonique et ultra-sonique qui utilise la particularité qu'ont les gaz d'être ionisés sous l'effet d'une tension électrique très élevée et de haute fréquence. Ce générateur est aussi un ozoniseur efficient et il est nécessaire de ne l'employer qu'avec une ventilation appropriée.

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Paper No. 2397 in the Journal Series of the Agricultural Experiment Station.