Investigating Environmental Toxicology to Reduce Human Health Risks

LRRI has a strong environmental research program that investigates the health effects of exposures to airborne materials in the outdoor, indoor, and workplace environments. The portfolio spans observational and hypothesis-driven strategies, and the goals, research tools, and investigators overlap with those in other programs to enhance our ability to deliver solutions to today's environmental problems.



LRRI has a longstanding and extensive experience in the conduct of routine and novel studies of the biological effects of inhaled materials, using a broad range of experimental designs, exposure strategies, and animal models.  

 Beginning in the early 1960s, LRRI not only moved to the front line in the conduct of basic and applied inhalation studies, but also the development and refinement of inhalation and lung biology research technology, the objective and scientifically sound interpretation of results, and the involvement of inhalation toxicologists at the science-policy interface.

The success of LRRI inhalation research has relied heavily on its ability to design and construct both novel and routine facilities for conducting animal exposures to simulated atmospheres.  The LRRI facility and research team were originally created to study the long-term, subtle effects of inhaled radioactive particles. 

That effort spanned a 30‑year period and provided a substantial portion of today’s information on the respiratory health hazards of airborne radionuclides, comparative interspecies quantitative morphology of the lung, comparative deposition and retention of particles, and comparative lung biology.

During the mid 1970s, LRRI research extended into the areas of aerosolized consumer products and environmental air pollutants.  LRRI research on engine emissions began 1979 and has continued almost unbroken, creating a record of studies and publications on the health effects of engine emissions that is unmatched by any other research organization in the world. 

Research on other workplace and environmental respiratory hazards has broadened progressively from the mid 1980s, to include such diverse topics as airborne biological aerosols in orthopedic surgical suites,  standard National Toxicology Program (NTP) protocol bioassays of commodity chemicals, airborne “red tide” toxins near Florida beaches, the causal components of complex combustion source emissions, efficacy and safety of inhaled pharmaceuticals, safety testing of new fuels and additives, and inhalation drug delivery technologies.  

Today LRRI is a leader in environmental respiratory health and has an established Environmental Respiratory Health (ERH) program built on decades of environmental health research. From their inception, LRRI research programs have focused on conducting important unbiased research that answers questions of policy relevance. The ERH program fits this paradigm.

Additional qualifications:

  • LRRI has over 250 publications in environmental toxicology
  • Three past Directors of the EPA Clean Air Science Advisory Committee have been LRRI scientists
  • Currently there is a LRRI Senior Scientist on the Board of Directors of Environmental Toxicology for National Academy of Sciences
  • LRRI has numerous current and past appointments to the National Academy of Sciences Committees on Environmental Toxicology such as Particulate Matter in the Middle East, Burn Pits in the Middle East, Particulate Matter Health Research, and Methyl Bromide
  • Currently our VP for Academic Research serves on the Board of Scientific Counsel for NIEHS

Key Findings and Activities of ERH Program:

Particulate Matter and Air Pollution Mixtures

  • Showed the importance of studying entire mixture (including gases) in ERH research
  • Findings played a role in re-shaping EPA research and funding strategy

Motor Vehicle Emissions

  • Showed that highly polluting vehicles are the most toxic
  • Determined that the lubrication oil component determines toxicity of emissions
  • Showed gasoline emissions can be just as toxic as diesel exhaust
  • Determined new biological mechanisms for cardiovascular response to engine exhaust
  • Showed that new diesel technology removes harmful effects of older technology

Secondhand Tobacco Smoke


  • Showed that previous reports of highly toxic pulmonary effects exaggerated
  • Identified important mechanism of Carbon Nanotube Immune suppression