Related Experiment Video
Updated: Jan 26, 2026

Author Spotlight: A Novel Protocol for Intracameral Injections to Enhance Precision in Rodent Ophthalmology
Published on: May 31, 2024
Particle size and composition related to adverse health effects in aged, sensitive rats
Fletcher F Hahn1, Edward B Barr, Margaret G Ménache
1Experimental Toxicology Program, Lovelace Respiratory Research Institute, 2425 Ridgecrest Dr SE, Albuquerque NM 87108, USA. FHahn.lrri.org
Abstract:
Small increases in concentrations of ambient particulate matter (PM*) have been linked to adverse health effects, especially in older people and people with preexisting respiratory disease. Some epidemiologic studies have shown the association to be stronger with PM less than 2.5 microm in aerodynamic diameter (PM2.5) than with PM less than 10 microm in aerodynamic diameter (PM10). Some scientists and regulators suggest that 2.5 microm might be an arbitrary cutoff and that the effects might be more pronounced for PM less than 0.1 microm in aerodynamic diameter (ultrafine PM). Our first aim was to determine the relation between size of respirable particles and particle toxicity, as well as the health effects of short-term increases (spikes) in particle concentration against backgrounds of relatively low or high baseline exposures. Our second aim was to determine the effect of spikes in concentration of fine particles (0.7 microm in mass median aerodynamic diameter [MMAD]) and ultrafine particles (35 nm in count median diameter [CMD]) of disparate composition: vanadium pentoxide (V2O5) and carbon black. The relative toxicity of these particles was determined in aged rats with mild pulmonary inflammation induced by instilled endotoxin. Our third aim was to determine the influence of age (aged vs young adult) on particle-induced toxicity in these rats.
More Related Videos
05:27Gap Junctional Intercellular Communication: A Functional Biomarker to Assess Adverse Effects of Toxicants and Toxins, and Health Benefits of Natural Products
Published on: December 25, 2016
07:57Prevention of Heat Stress Adverse Effects in Rats by Bacillus subtilis Strain
Published on: July 11, 2016
Related Concept Videos
Factors Affecting Dissolution: Particle Size and Effective Surface Area
Local Anesthetics: Adverse Effects
Once absorbed into the systemic circulation, local anesthetics can affect the organs that depend on the functioning of sodium...
Skeletal Muscle Relaxants: Adverse Effects
Unlike...
Insulin: Dosing Regimen and Adverse Effects
The basal dose constitutes about 40%-50% of the total daily dose, with the rest as premeal insulin. The mealtime insulin dose should mirror...
Basic Postulates of Kinetic Molecular Theory: Particle Size, Energy, and Collision
Precipitate Formation and Particle Size Control
The obtained precipitate should be either a pure substance of known composition or easily converted to one by a simple process, such as ignition or drying. In addition, the precipitate should be insoluble and easily filterable. In general, filterability...