Stella Koutros, Ph.D.


Occupational and Environmental Epidemiology Branch


9609 Medical Center Drive
Room SG/6E124
Rockville, MD 20850


Research Topics

Dr. Koutros’s research involves the design and conduct of epidemiologic investigations to evaluate occupational exposures as potential risk factors for cancer. She employs state-of-the-art exposure assessment methods and molecular studies within highly exposed populations to identify and clarify the biological mechanisms underlying chemical-induced carcinogenesis. She has a particular interest in the interaction between these exposures and inherited genetic variation, also known as gene-environment interaction, as well as the interplay between somatic variation and alterations at the tumor level and chemical exposures.

Effect of Agricultural Pesticide Use on Cancer Risk

Excess risks of cancer in agricultural populations have been attributed to several work-related exposures, including pesticides. Dr. Koutros and her collaborators are leading investigations in a large cohort of pesticides applicators, the Agricultural Health Study (AHS), to evaluate whether pesticide exposure influences cancer risk. In particular, work in the AHS has shown an increased risk of aggressive prostate cancer with exposure to specific organophosphate insecticides. Dr. Koutros also employs comprehensive information on genetic susceptibility for prostate cancer to study the interaction between agricultural pesticide use and cancer risk.

Chemical Exposures and Bladder Cancer

Occupational exposures are a leading risk factor for bladder cancer, second only to smoking. Dr. Koutros is currently leading efforts within large case-control studies of bladder cancer to identify important occupational exposures that might influence risk, in particular with exposure to diesel exhaust. Dr. Koutros and her collaborators are also examining potential gene-environment interactions as well as incorporating important somatic variation and bladder tumor marker data to integrate exposure, germline genetic variation, and somatic changes to gain insights into the mechanisms of bladder carcinogenesis.

Acrylonitrile and Cancer Mortality

Acrylonitrile is a major industrial chemical used in the production of a variety of consumer products. Each year, more than 10 billion pounds of acrylonitrile are produced globally. Animal studies suggest acrylonitrile as a multi-site carcinogen. Results from previous epidemiologic studies, though inconsistent, have suggested elevated risk for cancers of the lung, brain, prostate, and hematopoietic and lymphatic systems among acrylonitrile-exposed workers. As co-principal investigator of the largest study of acrylonitrile workers in the world, Dr. Koutros is helping to elucidate associations with cancer mortality to provide the most powerful epidemiologic evidence regarding human carcinogenicity to date.


Dr. Koutros received her M.P.H. and Ph.D. in epidemiology from Yale University. She completed her doctoral work through the Yale-NCI partnership training program in cancer epidemiology, conducting research in the Occupational and Environmental Epidemiology Branch (OEEB). In 2008, upon completion of her doctorate she became a fellow in OEEB; she was appointed to the position of tenure-track investigator in 2015.

Selected Publications

  1. Koutros S, Beane Freeman LE, Lubin JH, Heltshe SL, Andreotti G, Barry KH, DellaValle CT, Hoppin JA, Sandler DP, Lynch CF, Blair A, Alavanja MC. Risk of total and aggressive prostate cancer and pesticide use in the Agricultural Health Study. Am J Epidemiol. 2013;177(1):59-74.

  2. Koutros S, Beane Freeman LE, Berndt SI, Andreotti G, Lubin JH, Sandler DP, Hoppin JA, Yu K, Li Q, Burdette LA, Yuenger J, Yeager M, Alavanja MC. Pesticide use modifies the association between genetic variants on chromosome 8q24 and prostate cancer. Cancer Res. 2010;70(22):9224-33.

  3. Koutros S, Langseth H, Grimsrud TK, Barr DB, Vermeulen R, Portengen L, Wacholder S, Freeman LE, Blair A, Hayes RB, Rothman N, Engel LS. Prediagnostic Serum Organochlorine Concentrations and Metastatic Prostate Cancer: A Nested Case-Control Study in the Norwegian Janus Serum Bank Cohort. Environ Health Perspect. 2015;123(9):867-72.

  4. Koutros S, Silverman DT, Alavanja MC, Andreotti G, Lerro CC, Heltshe S, Lynch CF, Sandler DP, Blair A, Beane Freeman LE. Occupational exposure to pesticides and bladder cancer risk. Int J Epidemiol. 2016;45(3):792-805.

This page was last updated on November 29th, 2016