PubMed Health⌕ Search

Biomedical subjects

M Malanchuk

Publications and source records attributed to M Malanchuk.

6 recordsLinked to original sources
PubMed1977

Catalytically and noncatalytically treated automobile exhaust: biological effects in rats.

Chronic exposure to catalytically treated or noncatalytically treated automobile exhaust significantly depressed the spontaneous locomotor activity (SLA) of rats. Exposure to H2SO4 alone or CO at comparable levels did not alter the SLA. Exposure to noncatalytically treated exhaust resulted in significant reductions in growth rate and food and water intake. However, these effects were not evident in the exposure to catalytically treated exhaust or in the control H2SO4 and CO exposures. Blood acid-base analyses indicated that exposure to either catalytically treated exhaust or H2SO4 elicits a metabolic alkalosis, while exposure to CO alone results in a metabolic acidosis. All acid-base parameters were within the normal range several weeks after the termination of exposure.

Acid-Base Equilibrium↗
PubMed1976

Biologic effects of auto emissions. I. Exhaust from engine with and without catalytic converter.

This paper relates to the efficacy of a catalytic converter in reducing the levels of certain pollutants emitted from an automobile engine and to the reduction and/or elimination of gross biologic damages in animals exposed to emissions from an exhaust system containing such catalysts. Groups of rats were exposed to diluted emissions from an automobile engine with and without catalyst. Concomitantly, a comparative experiment was conducted by exposing a group of rats to carbon monoxide alone (575 mg/m3). The parameters measured included hematocrit, serum LDH, GOT, and lysozyme. An elevation in hematocrit was observed in animals of the experiment run without catalyst and in those exposed to carbon monoxide; the use of the catalyst reduced the carbon monoxide levels in the exposure chambers by more than tenfold and prevented these bioeffects from occurring. Serum LDH activity was elevated in the groups of rats in the experiment conducted without catalyst, but no alternation was observed in the animals from the experiment utilizing the catalyst or in those exposed to carbon monoxide alone. The data obtained in this study showed that acute exposure to noncatalytic emissions caused significant alterations in certain biologic parameters. Conversely, the introduction of an oxidizing catalytic converter into the engine exhaust system reduced or prevented such biologic damage.

Animals↗
PubMed1975

Inhalation toxicology of automotive emissions as affected by an oxidation exhaust catalyst.

Preliminary data are given on the acute inhalation toxicology of automotive emissions as affected by an oxidation exhaust catalyst. The catalyst effectively reduced CO and HC in the exhause which apparently had an effect (at least in a closed exposure system) on oxidant and NO2 levels by altering the HC/NOx ratio. There was a resultant reduction in biological effects due to the exposure. The catalyst altered the type of particulate to one which probably contained sulfuric acid as a major component. No evidence was present in these acute exposures to suggest a toxic response due to the higher sulfate emissions or possible catalyst attrition products. The effects of long-term exposure have not yet been investigated.

Air Pollution↗
PubMed1975

Whole body retention in rats of different 191Pt compounds following inhalation exposure.

The whole body retention, excretion, lung clearance, distribution, and concentration of 191Pt in other tissues was determined in rats following a single inhalation exposure to different chemical forms of 191Pt. The chemical forms of 191Pt used in study were 191PtCl4, 191Pt(SO4)2, 191PtO, and 191Pt metal. Immediately after exposure most of the 191Pt was found in the gastrointestinal and respiratory tract. Movement of the 191Pt through the gastrointestinal tract was rapid, most of the 191Pt being eliminated within 24 hr after exposure. Lung clearance was much slower, with a clearance half-time of about 8 days. In addition to the lungs, kidney and bone contained the highest concentrations of 191Pt.

Aerosols↗