Related Experiment Video
Updated: Feb 15, 2026

Cigarette Smoke Exposure in Mice using a Whole-Body Inhalation System
Published on: October 22, 2020
Prevalence of invehicle smoking and secondhand smoke exposure in Uruguay
Laura Llambi1, Mary Barros2, Carolina Parodi1
1Tobacco Cessation Clinic, Internal Medicine Department, Clinica Medica "A", Hospital de Clinicas, Facultad de Medicina, Universidad de la República, Montevideo, Uruguay.
Introduction:
Protection from secondhand smoke (SHS) is one of the fundamental principles of the WHO Framework Convention for Tobacco Control. Objective data on SHS exposure in vehicles in South America is scarce. This study aimed to estimate prevalence of smoking inside vehicles.
Methods:
The point prevalence of smoking in vehicles was observed, and a method for estimating smoking prevalence was piloted.
Results:
We observed 10 011 vehicles. In 219 (2.2%; 95% CI 1.91 to 2.49) of them, smoking was observed, and in 29.2% of these, another person was exposed to SHS. According to the 'expansion factor' we constructed, direct observation detected one of six to one to nine vehicles in which smoking occurred. The observed prevalence of smoking in vehicles (2.2%) could reflect a real prevalence between 12% and 19%. In 29.2% (95% CI 23.6 to 35.5) and 4.6% (95% CI 2.2 to 8.3) of vehicles in which smoking was observed, another adult or a child, respectively, was exposed to SHS.
Conclusions:
Smoking was estimated to occur in 12%-19% of vehicles, with involuntary exposure in one of three of vehicles observed. These data underscore a need for new public policies to eliminate SHS in vehicles to protect public health.
More Related Videos
Related Concept Videos
Prevalence and Incidence
Prevalence indicates the proportion of individuals in a population who have a specific disease or health...
Pharmacokinetic–Pharmacodynamic Relationship: Exposure, Response and Effect
What is an Electrochemical Gradient?
The chemical gradient relies on differences in the abundance of a substance on the outside versus the inside of a cell and flows from areas of high to low ion concentration. In contrast, the electrical gradient revolves around an...
Measures of Central Tendency
The Nernst Equation
The interconnection between standard cell potentials and various thermodynamic parameters such as the standard free energy change ΔG° and equilibrium constant K has been previously explored. For example, a redox reaction involving zinc(II) and tin(II) ions at 1 M concentration with Eºcell = +0.291 V and ΔG° = −56.2 kJ is spontaneous.
Biological Effects of Radiation

