Siddiqui, R. A., Harvey, K., and Stillwell, W. Anticancer properties of oxidation products of docosahexaenoic acid. (webmd.com)
In the atmosphere today, particle formation is dominated almost everywhere by mechanisms where at least three chemical components must come together: apart from the two basic substances, i.e. sulphuric acid and water, these are either ammonia or specific organic compounds such as oxidation products from terpenes. (sciencedaily.com)
The article above does distinguish between virgin and refined oil, edibleangela, in that the former has more antioxidants which helps reduce oxidation products during heating. (scienceornot.net)