Lifetime Profile of Testosterone in a Blue Whale Using its Waxy Earplug




Marks, Rachel

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Matrices such as ice cores and tree rings have been analyzed for chemical profiles that yield telling data on environmental changes, climate change, and contaminants [1, 2]. Much like these layered matrices, earplugs of the baleen whale (e.g. Balaenoptera musculus, blue whales) are hypothesized to contain lipophilic chemical secretions of hormones, in addition to other anthropogenic chemicals. Whales secrete earwax into their ear canals like all other mammals; however, the earwax remains compacted within the ear meatus for the entirety of the whale’s lifespan, resulting in the formation of a layered earplug. The layers of the earplug, called lamina, have been used to age whales, as each layer represents migratory and feeding patterns over time. It was hypothesized that lipophilic chemicals would be secreted along with the lipophilic cerumen matrix over time, yielding an earplug that contains an archive of a whale’s life of chemical exposures and secretions. A method was successfully developed to analyze the chemicals within the earplug. This thesis focuses on the feasibility of extracting testosterone from a male blue whale earplug sample.



Blue Whale., Testosterone., Earwax.