Allometric respiration/body mass data for animals to be used for estimates of inhalation toxicity to young adult humans.

The study examines the relationship between body weight and respiratory rates in young adult terrestrial mammals, aiming to improve estimates of inhalation toxicity for humans. The large dataset collected from the literature suggests that the minute respiratory volume links with body weight through an allometric relationship, making it useful for estimating toxic inhalation risks, especially for young adults like military personnel.

Research Methodology

• The researchers conducted a systematic review of existing literature to gather data on the body weight and respiratory rates (minute volume) of various terrestrial mammals.
• The dataset was divided into animals in two states – anaesthetised and non-anaesthetised, with a focus on the latter group.
• The target group for the gathered data comprised solely of young and healthy terrestrial mammals as they most closely relate to the target human population i.e., physically fit young adults.

Composition of the Data Set

• The dataset for non-anaesthetised animals comprised of 142 studies, representing 2616 individual animals from 18 different species.
• The species ranged significantly in size. The smallest ones were mice around 12g body weight, while the largest included horses and giraffes weighing approximately 500 kg.

Results and Key Findings

• Analysis of the data showed an allometric (power law) relationship between minute volume and body weight.
• This was represented using the equations: log(10)V(m)= -0.302 + 0.809 log(10)BW and V(m) = 0.499 BW(0.809), where V(m) represents the minute volume and BW refers to body weight.
• From this relationship, the research derived a minute volume of 15.5 lmin(-1) for a 70 kg human in a similar physiological and emotional state as the studied animals.
• The results of these observations were compared with other studies. The more recent ones also suggested a similar scaling factor of 0.8.

Implications for Inhalation Toxicity Estimates

• The study recommends the use of these findings for estimating the inhalation toxicity risks for young adult humans, specifically military personnel.
• The allometric relationship between minute volume and body weight, as depicted in this research, offers a robust basis for such estimations.
• This study is unique in its use and focus on a large dataset of non-anaesthetised young adult terrestrial mammals, adding greater value and relevance to its applications for human inhalation toxicity estimates.