[2][3] Robertson's scientific research focuses on the mechanisms of toxicity of polyhalogenated aromatic hydrocarbons, e.g. polychlorinated biphenyls (PCBs), dibenzodioxins (PCDDs), dibenzofurans (PCDFs) and various pesticides.
Recent work comprises the metabolism of halogenated compounds to show oxidative events, which lead to increased oxidative DNA damage - in important factor in the cancerogenic potential of a compound.
Robertson received international recognition for hosting the First PCB Workshop (Recent Advances in the Environmental Toxicology and Health Effects of PCBs), held at Lexington, KY, April 9–12, 2000.
A resulting publication was edited with Larry G. Hansen and accepted as reference work.
Robertson was appointed professor of toxicology at The University of Iowa College of Public Health in 2003.