[7] He also examines the regulation of steroid biosynthesis,[8] intracellular compartmentalization and homeostasis by hormones,[9] chemicals, drugs, natural products and environmental factors.

[13] In 1988, Papadopoulos was appointed to the faculty of Georgetown University School of Medicine[2] where he continued research on the regulation of steroidogenesis to identify the mechanisms of action of DBI on mitochondrial steroid formation in steroidogenic cells.

[17] His research on steroidogenesis continued at McGill, focusing on the mechanisms of mitochondrial cholesterol import[8] and the synthesis of steroids and oxysterols in adipocytes[18] and prostate.

This focus on steroidogenesis revealed the mitochondrial protein complex that drives cholesterol import, trafficking, and metabolism for steroid hormone production.

[2] Moreover, the identification of a brain-specific pathway for dehydroepiandrosterone steroid synthesis led to the development of a novel Alzheimer's blood diagnostic[27] and the design of neuroprotective drugs.

[29] Endocrine disrupting chemicals such as phthalate DEHP and the non-phthalate DINCH reduced testosterone and aldosterone formation in adult rats.

[2] Under Papadopoulos' tenure, more than $300 million federal and provincial grants were raised, resulting in the creating of a state-of-the-art clinical and biomedical research facility.