Abstract  Investigation report on an explosives manufacture following several accidental fatalities and cases of poisoning by exposure to harmful substances (RDX, nitroglycerine, oxides of nitrogen, nitrocellulose, acids). Topics covered: description of the site (history, organisation); minutes of public audiences; explosives chemistry, manufacturing processes, associated hazards; analysis of safety, hygiene and occupational health problems; conclusions and recommendations.

Abstract  A dog suspected of having ingested minute quantities of plastic explosive type 4 (PE4 containing cyclonite) was presented with congested mucous membranes, a fever, an increased pulse rate, hyperventilation, hypersensitivity and mild convulsions. Experimental poisoning of a dog confirmed the neurotoxic properties of PE4 and proved to be fatal at 14 mg kg-1 within 18 h after ingestion. The clinical signs and post mortem findings closely resembled strychnine poisoning in dogs.

Abstract  RDX is an explosive compound widely used by the military and is the main component of the plastic explosive composition C-4. RDX has been detected as a soil and groundwater contaminant at some Army training facilities. In humans, toxic ingestion or exposure to RDX has caused headache, dizziness, vomiting, confusion, and seizures. However, the mechanism(s) of RDX-induced seizures are not understood. Early behavioral studies speculated that RDX seizures originated in the limbic system, possibly in the amygdala. Thus, our studies began by investigating the electrophysiological effects of RDX on the basolateral nucleus of the amygdala (BLA), the nucleus that is most susceptible to seizurogenic insults. First, we confirmed that RDX administration (75 mg/kg, orally) in male Sprague Dawley rats (275-325g) rapidly caused generalized seizures in vivo, by recording cortical electrographic activity using screw electrodes bilaterally over the frontal and parietal cortices. Next, using whole-cell recordings in the voltage-clamp mode, in in vitro brain slices from 14-21 day-old, male Sprague Dawley rats, GABAA receptor-mediated spontaneous inhibitory post-synaptic currents (sIPSCs) were recorded from pyramidal-shaped neurons in the BLA, in the presence of 50 μM D-APV, 50 μM GYKI 53655, and 10 μM SCH50911 to block NMDA, AMPA, and GABAB currents, respectively. Upon application of 30μM RDX, the amplitude, but not frequency, of sIPSCs was markedly reduced. Subsequent application of 10 μM bicuculline completely blocked the sIPSCs, confirming that the currents which were reduced by RDX were mediated by GABAA receptors. We are now constructing a dose-response curve for the effect of RDX on the sIPSCs, as well as for the effect of RDX on IPSCs evoked by local pressure application of variable concentrations of GABA. The reduction of GABAA receptor-mediated currents by RDX in the BLA may be an important mechanism in the generation of seizure activity upon RDX ingestion or exposure.

Abstract  BIOSIS COPYRIGHT: BIOL ABS. RRM MEETING ABSTRACT PLASTIC EXPLOSIVE RDX ENVIRONMENTAL CONTAMINANT ANTIBODY ANALYTICAL METHOD

Abstract  Studies were conducted with RDX to evaluate the mutagenic effects (Ames Salmonella/microsome test dominant lethal assay) and reproductive effects (teratology, two-generation reproduction) in Charles River CD rats and New Zealand white rabbits. Mutagenic studies. RDX produced numbers of revertants similar to those in vehicle-treated controls at doses up to 1 mg/plate in all five strains of S. typhimurium, both without and with activation with the S-9 fraction (Aroclor 1254). Groups of male rates from the F0 reproduction study were fed RDX diets containing 0, 5, 16, or 50 mg/kg/day for 13 weeks and then mated with virgin females. There was no evidence of either a preimplantation loss of blastocysts or a post-implantation loss of embryos. RDX therefore is not mutagenic in the Ames and dominant lethal tests. Reproductive studies. Animals were given RDX suspensions by gavage at dose levels of 0, 0.2, 2.0 and 20 mg/kg/day; rats on days 6 to 19 and rabbits on days 7 to 29 of gestation. RDX was not teratogenic to rats and rabbits although maternal toxicity (neurotoxicity), lethality and embryotoxicity were seen in the high dose rats. No effects were seen at the 2 mg/kg level. Four groups of rats (22/sex/group) were fed RDX diets at levels of 0, 5, 16, and 50 mg/kg for 13 weeks and then mated. The F1 generations (26/sex/group) were similarly mated after 13 weeks on the diets. Reproduction was adversely affected only in the high dose group; fertility, viability and lactation indexes were reduced.