Air pollution is associated with an increased risk of heart disease, and researchers say a "natural experience" that includes traveling to a much more polluted city than their city has provided evidence of how that damages blood vessels over time.
The researchers measured levels of products for the analysis of pollution and proteins associated with the risk of heart disease in the blood of 26 healthy young adults from Los Angeles, before, during and after a visit to Beijing as part of a summer study program, according to Reuters.
The study team reported in the journal "Circulation" that the pollutant metabolites in the urine of the participants jumped with signs of inflammation and the accumulation of deposits inside the arteries after they spent between six and eight weeks in the Chinese capital.
The study team noted that air pollution is a serious public health problem in China as it negatively affects the heart health of 1.4 billion people.
The researchers found that the levels of air pollution particles increased when students in Beijing were 371 percent higher than in Los Angeles, while the level of urine pollution outputs increased to concentrations of 176 percent, an increase of 800 percent over Los Angeles.
The researchers said that enzymes that induce good cholesterol became weak when students were in Beijing, but good cholesterol levels did not drop.
They also found that fibrinogen, a blood marker of inflammation, rose about 50 percent, and C-reactive protein, another sign of inflammation, increased to almost lesbian. The levels of fat oxidation indicators, which contribute to the accumulation of arterial deposits, have increased in the blood.
The research team found that the effects of exposure to pollution in Beijing were reversed after students returned to Los Angeles, but they indicated that it was not yet known whether short visits to areas with severe air pollution might increase the risk of chronic cardiovascular disease.