Starting the engine of your car, lighting the fireplace or BBQ, standing next to the copy machine. These all seem harmless activities, but in fact each of them produces and emits soot particles. Research has already proven that inhaling these particles causes severe health effects. As a result, each year, a staggering amount of people dies prematurely due to daily inhalation and exposure to soot particles. It is an urgent matter to come up with a solution for this global burden of disease and to safeguard everyone's health. Unfortunately, up to know, researchers have been groping in the dark about the exact toxicological mechanisms of soot particles. This because there is no available screening technique to monitor personalized exposure to these materials that allows accurate correlation to observed health effects.
Here, an innovative optical-based analytical technique was developed to finally close the diagnostic gap. It includes the illumination of the soot particles with ultrafast and ultrashort laser pulses making them act as nanolights generating bright light including all colors of the rainbow. The potential of this novel method was demonstrated in both biomedical and diagnostic context. The approach allows readily visualization and quantitative determination of soot in complex biological environments such as human lung cells. Moreover, it was shown, using children's urine, that urinary carbon loading can serve as an exposure matrix to soot-based air pollution reflecting the passage of soot particles from circulation into urine. The results clearly showed that the novel technique has numerous advantages, as it is a straightforward, fast and flexible approach without the need of sample pretreatment, which results in high throughput screening. Moreover, the screening tool discriminates background signals from biological components, and allows 3D imaging and high imaging depths, making it also possible to screen at the cellular and tissue level.
In conclusion, this novel diagnostic technique makes it possible to gain up-to-date knowledge about the severity of exposure and impact of air pollution on the human health in different scenarios like occupational exposure, smog, forest fires, etc. Additionally, it will certainly show its utility to unravel the complexity of soot-related health effects.