PubMed Health⌕ Search

Biomedical subjects

K C Back

Publications and source records attributed to K C Back.

8 recordsLinked to original sources
PubMed1978

Occupational hazards of missile operations with special regard to the hydrazine propellants.

The second generation of ballistic missiles and boosters, characterized by increased range and quick reaction capability, required the development of new high-energy storage propellants. This exploration led to the introduction of hydrazine (Hz), monomethylhydrazine (MMH), and 1,1-dimethylhydrazine (UDMH) into the USAF inventory. These compounds are all storable, noncryogenic, high-energy fuels which may be used alone or in combination as mixed amine fuels. Early toxicology experiments were to produce data on acute and subacute effects of the propellants in order to set standards for test and operational procedures to protect propellant handlers. The early work indicated that, despite similar chemical characteristics, there were marked differences between the compounds in terms of toxicological mechanisms. Since the propellant systems have been used for some 15 years, recent emphasis on toxicology has been centered on the more chronic effects and on an increasing body of evidence from animal experiments that the compounds may possess oncogenic potential as well as chronic systemic effects. This paper addresses itself to data leading up to current occupational standards.

Alopecia↗
PubMed1975

The treatment of ethylene glycol toxicosis with pyrazole.

Rats and dogs were protected from the effects of lethal doses of ingested ethylene glycol (EG) with pyrazole (P), an inhibitor of liver alcohol dehydrogenase. Rats given 1.35 ml/100 g of EG followed by 2.2 mmol/kg of P i.p. at 6 and 30 hours postingestion survived. Untreated control animals died. Dogs were given either 10.0 or 12.5 ml/kg of EG and treatment was begun 6 hours later. The control treatment consised of NaHC03 administered i.v. according to the calculated base deficit, B-complex vitamins with ascorbic acid, hydrocortisone, and 5 per cent glucose in water. The addition postexposure to this treatment of 0.9 mmol/kg of P and 0.5 mmol/kg of P at 6 and 30 hours, respectively, constituted the experimental therapy. In summary: with 10 ml/kg of EG, no P, 2 of 5 dogs survived; 12.5 ml/kg of EG, no P, 0/1; 10 ml/kg of EG plus P, 9/11; 12.5 ml/kg of EG plus P, 12/22. Dogs that succumbed had large numbers of oxalate crystals in their kidneys at necropsy. The surviving dogs had few oxalate crystals in their kidneys at the time of unilateral nephrectomy (2 weeks postexposure) or necropsy (30 days postexposure). Several clinical factors were identified as useful prognostic indicators in the treatment of EG poisoning. The results suggested that pyrazole, despite its marked toxicity, may be of clinically significant value in the treatment of ethylene glycol poisoning when therapy is initiated withing 6 hours of exposure.

Animals↗