Inhaled exposure to air fresheners aggravated liver injury in a murine model of nonalcoholic fatty acid liver disease

At present, the consumption and use of air fresheners (AFs) is rapidly increasing worldwide for the purposes of odor removal and to create a pleasant odor. Many recent studies have strongly suggested that the potentially hazardous chemicals emitted from AFs may be the primary source of indoor air pollutants and may cause adverse health effects. Despite the presence of hazardous chemicals in AFs, potential adverse health effects and risk assessment of AFs have not yet been established. The incidence of nonalcoholic fatty acid liver disease (NAFLD) around the world is rapidly increasing, as with obesity and diabetes, and is one of the most common causes of liver disease worldwide. Based on the demonstrated evidence that NAFLD could eventually develop into further health complications such as liver failure, cardiovascular disease, liver cirrhosis, or liver cancer, the current study was performed to clarify the relationship between inhaled AF exposure and NAFLD using a high-fructose diet (HFr)-induced murine model. The results from current study clearly demonstrated that AF exposure further exacerbated liver injury in NAFLD-induced mice. Interestingly, the increased expression of fibrosis-related factors and collagen accumulation in the liver of AF-exposed NAFLD-induced mice resulted in nonalcoholic steatohepatitis (NASH)-like phenotype and fibrosis. Taken together, these results strongly suggest that AF exposure may not only induce liver injury but may also exacerbate NAFLD to lead to NASH-like symptoms. Further study is needed to shed light on the detailed mechanisms behind AF-induced liver effects and its potential role in exacerbating NAFLD to more detrimental disease in order to better scientific evidence for risk assessments of indoor AF exposure.