Gasoline particle filter reduces oxidative DNA damage in bronchial epithelial cells after whole gasoline exhaust exposure in vitro

Abstract

A substantial amount of traffic-related particle emissions is released by gasoline cars, since most diesel cars are now equipped with particle filters that reduce particle emissions. Little is known about adverse health effects of gasoline particles, and particularly, whether a gasoline particle filter (GPF) influences the toxicity of gasoline exhaust emissions. We drove a dynamic test cycle with a gasoline car and studied the effect of a GPF on exhaust composition and airway toxicity. We exposed human bronchial epithelial cells (ECs) for 6 hours, and compared results with and without GPF. Two hours later, primary human natural killer cells (NKs) were added to ECs to form cocultures, while some ECs were grown as monocultures. The following day, cells were analyzed for cytotoxicity, cell surface receptor expression, intracellular markers, oxidative DNA damage, gene expression, and oxidative stress. The particle amount was significantly reduced due to GPF application. While most biological endpoints did not differ, oxidative DNA damage was significantly reduced in EC monocultures exposed to GPF compared to reference exhaust. Our findings indicate that a GPF has beneficial effects on exhaust composition and airway toxicity. Further studies are needed to assess long-term effects, also in other cell types of the lung.

Toxicological evaluation of exhaust emissions from light-duty vehicles using different fuel alternatives in sub-freezing conditions

“…Similar results have been observed in the previous studies [40,54,71]. However, since the exhaust gas PN emissions from gasoline powered cars were considerably high compared to Euro 6 diesel and CNGpowered cars, one possibility for reducing PM emissions would be the implementation of the gasoline particle filters (GFP) which have been shown to reduce PM mass and PN emissions also in cold running temperatures [30] and decrease the toxicity of the gasoline exhaust [63]. Moreover, the multi-fold differences between the PAH concentrations in emissions from different Euro 6 cars is striking, as each of these cars are presentation of the modern technology.…”

“…It indicates that the observed cytotoxicity was likely consequence from the ongoing process of apoptosis. The mutagenicity of E10 showed several times higher mutagenic potential compared to other Euro 6 car originated PM, thus indicating carcinogenicity, which have been associated with gasoline engine PM previously [63]. However, results from DCF and DTT assays indicate that exhaust PM from E10 fuelled passenger car did not result to oxidative stress in vitro nor had higher oxidative potential than other Euro 6 car originated PM.…”

Oxidative stress-induced inflammation in susceptible airways by anthropogenic aerosol

“…It has also been suggested that PM transition metals and organic species (e.g. quinones) lead to the generation of free radicals in the lung environment and thereby induce oxidative stress [13,14]. The ability of PM from both primary and secondary sources to generate oxidative stress has been described as oxidative potential (OP).…”

Application of green tea catechins, polysaccharides, and flavonol prevent fine dust induced bronchial damage by modulating inflammation and airway cilia

“…Human bronchial epithelia are invariably exposed to toxic factors such as FDPs, which can cause acute and chronic pulmonary infections and respiratory diseases 2 . In addition, toxic pollutants induce oxidative stress and imbalance between reactive oxygen species (ROS) production and scavenging 3 . Elevated oxidative stress causes airway epithelial barrier dysfunction, airway inflammation, infection, and mitochondrial dysfunction 4 .…”