Inhaled Ultrafine Particles Pass into the Bloodstream
With the aid of a radioisotope enhanced imaging technique, researchers in Belgium have shown that ultrafine particles can enter a person’s bloodstream from the lungs.
This study of human volunteers was intended to investigate whether the smallest particles can move from the lungs into the circulation, where they might have a direct effect on cardiovascular endpoints.
Alternative hypotheses hold that particles produce pulmonary inflammation with a systemic release of cytokines, which may influence cardiovascular endpoints. Alternately, it has also been proposed that pollutants may cause alterations in cardiac autonomic function thus causing changes in heart rate variability and increasing the risk of sudden cardiac death.
The investigators conclude that “…we are confident that our findings provide plausible evidence for particle translocation from the lung into the blood and then its distribution to the organs,” and that this process could account for cardiovascular illness and death related to ambient particle pollution.
Nenmar, A., Hoet, P.H.M., Vanquickenborne, B., Dinsdale, D., Thomeer, M., Hoylaerts, M.F., Vanbillioen, H., Mortelmans, L., Nemery, B., Passage of Inhaled Particles in to the Blood Circulation in Humans. Circulation, Vol. 105, pp. 411-414, 2002.
The American Heart Association [circ.ahajournals.org] offers the abstract online.
