Non-Hodgkin’s lymphoma (NHL) is the fifth most common cancer in Canada, and incidence has been increasing steadily for the past 30 years. However, at present, little is known about the risk factors for developing this cancer of the lymphatic system. Danhong Shu is examining whether exposure to organochloride compounds (chemicals such as DDT and PCB) increases the risk for developing Non-Hodgkin’s lymphoma, and whether certain genetic factors may also contribute to increased or decreased susceptibility to NHL. Using blood and mouthwash samples from 1,600 test subjects, she is comparing organochlorine levels between people with NHL and those who are cancer free. In addition, Danhong is using these samples to compare genetic patterns that may point to increased susceptibility to this type of cancer, focusing on genes involved in the metabolism of organochlorines (Ahr and CYP1A1). This research could confirm environmental risks and genetic susceptibility for Non-Hodgkin’s lymphoma, and help explain how the disease develops. Ultimately, the information may lead to preventive measures to limit environmental exposures and reduce the risk of NHL.