Methylsiloxanes in plasma from potentially exposed populations and an assessment of the associated inhalation exposure risk

Dimethylmethylphosphonate (DMMP) is a simple organophosphate used industrially as a flame retardant and to lower viscosity in polyester and epoxy resins. The military considered the use of DMMP as a nerve gas simulant. Since military use of DMMP involved exposure by inhalation, there was a need for a subchronic inhalation exposure to DMMP to fully investigate its toxic potential.Male Fischer-344 rats were exposed to 25 ppm or 250 ppm DMMP vapor on a continuous basis for 90 days. An equal number of control rats were sham-exposed. Following the 90-day continuous exposure period, 15 male rats were sacrificed from each group. Two rats from each group had the left kidney perfused for electron microscopic examination. The kidneys were perfused from a height of 150 cm water with 1% glutaraldehyde in Sorensen's 0.1M phosphate buffer pH 7.2. An additional kidney was taken from a rat in each group and fixed by immersion in 2.5% glutaraldehyde and 2% paraformaldehyde in 0.1M cacodylate buffer pH 7.4. A portion of the 9 kidneys collected for electron microscopy were processed into Epon 812. Thin sections, stained with uranyl acetate and lead citrate, were examined with a JEOL 100B Transmission Electron Microscope. Microvilli height was measured on photographs of the cells of proximal tubules. This data, along with morphologic features of the cells, allows the proximal convoluted tubules (PCT) to be identified as being S1, S2, or S3 segment PCT.

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Evaluation of hippocampus in rhesus monkeys after chronic (1-year) inhalation exposure to marijuana: I. Electron microscopy

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100159539 ◽

1990 ◽

Vol 48 (3) ◽

pp. 398-399

Author(s):

A.M. Andrews ◽

S.W. Wilson ◽

A.C. Scallet ◽

S.F. Ali ◽

J. Bailey ◽

...

Keyword(s):

Synaptic Vesicles ◽

Rhesus Monkeys ◽

Low Dose ◽

Inhalation Exposure ◽

Synaptic Cleft ◽

High Dose ◽

Withdrawal Time ◽

Treatment Groups ◽

Ultrastructural Evidence ◽

Male Rhesus

Exposure of rhesus monkeys (Macaca mulatta) to marijuana via inhalation or to intravenous delta-9-tetrahydrocannabinol (THC), reportedly caused ultrastructural evidence of increased synaptic width. Chronic marijuana smoke in a single rhesus monkey examined after a six month withdrawal time caused ultrastructure changes in the septal, hippocampal and amygdala regions; the synaptic cleft was widened, electron opaque material was found in the cleft and in the pre- and postsynaptic regions, with some clumping of the synaptic vesicles. The objective of our study was to assess neuropathological alterations produced by chronic inhalation of marijuana smoke.Nineteen male rhesus monkeys, 3-5 years of age and weighing 3-8 kg, were divided into four treatment groups: a) sham control, b) placebo smoke (7 days/ week) c) low dose marijuana (2 times/week with 5 days/week sham) and d) high dose marijuana (7 times/week). A smoke exposure consisted of smoke from one cigarette (2.6% THC) burned down to 10 mm butt length. Smoke was administered via smoke generator (ADL II, Arthur D. Little, Inc. Cambridge, MA) and nose-mouth only masks (local production) equipped with one-way valves.

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Evaluating Performance Effects of Low-Level Inhalation Exposure to Nerve Agents in Rats

PsycEXTRA Dataset ◽

10.1037/e448352006-001 ◽

2004 ◽

Cited By ~ 1

Author(s):

Raymond F. Genovese ◽

◽

Sara J. Shippee ◽

Jessica Bonnell ◽

Bernard J. Benton ◽

...

Keyword(s):

Inhalation Exposure ◽

Nerve Agents ◽

Low Level ◽

Performance Effects

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Clinical Policy for the Initial Approach to Patients Presenting With Acute Toxic Ingestion or Dermal or Inhalation Exposure

Annals of Emergency Medicine ◽

10.1016/s0196-0644(99)70206-4 ◽

1999 ◽

Vol 33 (6) ◽

pp. 735-761

Keyword(s):

Inhalation Exposure ◽

Initial Approach ◽

Toxic Ingestion ◽

Acute Toxic

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217. Design and Operation of a Popcorn Butter Flavoring Inhalation Exposure System

10.3320/1.2766143 ◽

2002 ◽

Author(s):

T. Goldsmith ◽

D. Frazer ◽

W. McKinney ◽

W. Jones

Keyword(s):

Inhalation Exposure ◽

Exposure System

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DECONTAMINATION OF VETERINARY SURVEILLANCE OBJECTS BY NEW GENERATION MEDICINE

Vestnik of the Russian agricultural science ◽

10.30850/vrsn/2019/2/64-67 ◽

1970 ◽

pp. 64-67

Author(s):

М. S. Saypullaev ◽

А. U. Koychuev ◽

Т. B. Mirzoeva

Keyword(s):

Staphylococcus Aureus ◽

Inhalation Exposure ◽

Gram Negative Bacteria ◽

Hazard Class ◽

E Coli ◽

Highly Efficient ◽

Mucous Membranes ◽

Environmentally Safe ◽

New Generation ◽

And Staphylococcus Aureus

The successful conduct of disinfection measures largely depends on the availability of veterinary practice a highly efficient, environmentally safe disinfectants. In this regard, finding new highly efficient disinfectant remains relevant. Studies found that the "Polied" (OOO "Razvitie XXI Vek, Russia) can be attributed to the highly efficient and environmentally friendly means. Solutions "Polied" have a high disinfectant activity against smooth and rough surfaces in the laboratory against gram-positive, gram-negative bacteria, mycobacteria and spores of microorganisms. Studies have established that solutions should be "Polied" obezzarajivatmi E. coli (EA 1257) concentrations of 0.1% on smooth surfaces and Staphylococcus aureus concentration of 0.05% in 1 hour from the calculation of 0.25-0.3 litres/m2. Disinfection of rough test surfaces against Escherichia coli and Staphylococcus aureus occurred after treatment with 0,3% solution of 3-hour exposure, at a rate of 0.5 l/m2. It was also found that 1.0% solution "Polied" fully obezzarazhivatel test the surface of mycobacteria (PCs-5) and at double the 0.6% concentration for 24 hours. Disinfection of rough test surfaces contaminated with spores of B. cereus (PCs 96) was achieved with a 4.0% solution at twice the irrigation rate of 0.5 l/m2 at an exposure of 24 hours. Toxicity solutions of the drug "Polied" refer to "moderate" threat (hazard class 3) and low-hazard substances (4 hazard class) when applied to the skin, mucous membranes of the eyes, and inhalation exposure on the respiratory system.

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