The primary soup and the major role of PAHs
Life needs organic molecules. Those organic molecules were initially synthesized endogenously and delivered exogenously.
The PAHs production in human societies and their risks
Both combustion of fossil and biomass fuels and cooking produce PAHs.
They are carcinogenic for animals and human.
But it seems that they are also linked to epigenetic changes which lead to asthma and allergy. So you can cook but try to produce the least of PAHs... As our ancestors probably did because of the scarce avalilability of energy.
Walker A, et al "Exposure to polycyclic aromatic hydrocarbons is associated with higher levels of total IgE, decreased function of T regulatory cells and an increase of asthma occurrence in children" AAAAI 2013; Abstract 197.