Toxicological effects of indoor PM10 in urban primary schools in Barcelona, Spain

摘要

Background. The BREATHE project, funded by the EU and led by CREAL in Spain, has conducted a campaign measuring aerosols in primary schools in Barcelona. Monitoring sites were separated into high and low-pollution areas with the primary aim of recognizing if differences in air pollutants affect the neurological system of children and their behaviour at school. Aims. Within BREATHE the CECAT sub-project is considering the toxicological aspect of the problem by investigating the toxicity of PM looking at its ability to induce a systemic oxidative stress which damages cells and DNA molecules. Methods. A total of 20 schools were sampled (10 with high traffic density and 10 with low). The sampling took place inside the classrooms for 4 consecutive days at 2 different times a year (winter/summer 2012) to take into account the changes of air pollutants in different climatic conditions. To determine particle oxidative capacity, PM10 in the classrooms was collected using an Airborne Sample Analysis Platform system (ASAP; Model 2800 Thermo) on PUF substrates (sample flow-rate 200 l/min). The genotoxicity, inflammatory potential and cytotoxicity of the PM10 samples are being elucidated using 3 complementary biological assays: Plasmid Scission Assay (PSA) - genotoxicity; DCFH ROS Assay - potential pro-inflammatory; F-actin polymerisation Assay - cytotoxicity. Results. PSA results show the PM dose able to damage 50% of a plasmid DNA molecule (TD50 values), an indication of the ability of the PM sample to exert potential oxidative stress. The TD50 values obtained so far reveal wide variations, although most values are higher than those for outdoor air, implying that PM in indoor air is causing less damage. There does not appear to be an obvious link between TD50 values and concentrations of NO2 and Black Carbon. The full toxicological dataset, including DCFH and ROS F-actin polymerisation assays will be presented at the conference.