Wayne State Study: Air Pollution Exposure Causes Liver Fibrosis


Exposure to air pollution has a direct adverse effect on the liver and causes liver fibrosis, an illness associated with liver cancer, says a new study released by Wayne State University.

“Our work defined that air pollution, specifically PM2.5 pollutant, is an independent risk factor of liver fibrosis. This is very significant in terms of identifying new health risk factors and understanding liver diseases,” says Kezhong Zhang, associate professor of molecular medicine, genetics, immunology, and microbiology at Wayne State and the principal investigator of the study.

Zhang’s Wayne State research group, along with researchers from Ohio State University, performed short-time and long-term inhalation exposure of animal models to PM2.5. The pollutant is a mixture of particles and gases from gasoline and diesel engines, along with dust from the wear of road surfaces, tires, and brakes. Zhang says PM2.5 is the major and most toxic component of air pollutants in environments such as heavy traffic or industrial activity. After a 10-week exposure, the animals developed liver fibrosis.

Zhang says the pollutant has a major impact on the health of people living in urban areas and Detroit is one of the most PM2.5-polluted cities in the nation, according to annual air quality reports by the American Lung Association.

Zhang says the liver is the major organ that detoxifies the body and a key player in disease development under exposure to pollutants. The report found exposure to high concentrations of PM2.5 has direct effects on the liver, triggering liver fibrosis, a pathological condition characterized by accumulation of protein collagen that occurs in most types of chronic liver diseases.

“Physicians or health care professionals should monitor liver pathology and consider preventive therapeutic strategies for liver disease for populations and patients in urban air pollution environments,” Zhang says.

Exposure to Fine Airborne Particulate Matters Induces Hepatic Fibrosis in Murine Models is published in the Journal of Hepatology.