Barbecues

Toxicity of combustion emissions from barbecue firelighters

Abstract

More and more people are willing to spend their time having barbecues with their families or friends. It is now easy to obtain small and high energy release products, which are widely used to ignite the barbecue fuels, such as wood and coal. I have found from research that firelighters have been the primary choice for igniting barbecues. The combustion emissions of barbecue fuels have been widely researched. However, the combustion emissions of barbecue firelighters, in contrast, are rarely studied. Therefore, people know little or nothing about the toxicity of the emissions from the combustion from the barbecue firelighters.

The primary aim of this research is to design an experiment to test the barbecue firelighters’ emissions, analyze the concentration of regulated emissions and identify the composition of unregulated emissions from the combustion of barbecue firelighter, then to discuss the health impact of these toxic emissions. Six barbecue firelighters, made of various materials were selected for all the experiments while keeping barbecue firelighters’ caloric value the same.

HORIBA MEXA 9400 and CVS-9100 Exhaust Gas Analyzers were chosen for measuring the concentration and percentage of regulated emissions such as carbon monoxide (CO), carbon dioxide (CO2), nitrogen oxides (NOx) and total hydrocarbons (THC). Agilent 7890B/ 5977A GC-MS was used to identify the composition of unregulated emissions, which were mainly Polycyclic Aromatic Hydrocarbons (PAHs).

The experiment results show that the concentration of regulated emissions were associated with the material of barbecue firelighters. Six different barbecue firelighters all have high level of CO, CO2, NOx and THC but the highest level of CO was emitted from wood based barbecue firelighters. The reason for this is that plenty of CO will be released during incomplete combustion of wood. Urotropine (C6H12N4) based firelighter released more NOx because it contains nitrogen. Kerosene is made from petroleum, so it only contains carbon and hydrogen. Thus, kerosene based firelighter released THC much quicker and much more than others. The regulated emissions can cause headache, vomiting and even respiratory problems and death.

As for unregulated emissions, results show that 5 PAHs (acenaphthylene, phenanthrene, anthracene, fluoranthene and pyrene) were found in the emissions of all these firelighters. These PAHs will damage the lung function of the patient. Mixtures of PAHs are also known to cause skin irritation and inflammation and/or even cancer.

Thesis submitted for a Masters of Science in Mechanical Engineering by Zekai Chen. The entire thesis can be found www.co-gassafety.co.uk

Zekai Chen is particularly grateful for the assistance given by Dr Paul Hellier.

For the full thesis click here.