2025/01/21 by Edson Plasencia Sánchez, Mònica Rosell, Clara Torrentó +6 · 1 voice
Environmental Science · #Air Quality Monitoring and Forecasting #Air Quality and Health Impacts #Heavy metals in environment
paper · doi:10.1016/j.atmosres.2025.107939
openalex publication_date 2025/01/21 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/22
A total of 75 outdoor PM 10 , PM 2.5 , and PM 1 samples from 14 schools, and 9 samples from potential local emission sources, were collected and analysed for their metallic content and lead (Pb) isotope ratios in 2 seasonal campaigns in Tarragona (Catalonia, Spain) to identify and apportion contamination sources and to assess associated health risks. Lead was predominantly found in PM 1 , and although its levels were below air quality standards, its Enrichment Factors (EF), along with those of other potentially toxic elements (Cd, Cr, Cu and Sb), indicated extremely severe enrichment in all PM sizes. Seasonal differentiation in Pb enrichment was particularly significant in PM 1 during the cold campaign. This suggests an anthropogenic origin, mainly from combustion processes such as road traffic and a municipal solid waste incinerator, as supported by profiles of other metals (Cu, V and Zn) and the spatial distribution of the EF Pb , respectively. Non-radiogenic Pb isotope ratios ( 208 Pb/ 204 Pb and 206 Pb/ 204 Pb) indicated a geogenic origin in some PM 10 samples, based on their similarity to the geochronology of specific Spanish ore samples. However, radiogenic ratios ( 208 Pb/ 207 Pb and 206 Pb/ 207 Pb) pointed to coal-fired electrical plants (EGUs) and road traffic as the sources of the majority of the samples. These findings were corroborated by EF spatial distribution maps and by our previous study coupling air masses back trajectories with C and N isotopes in the same PM samples. Bayesian mixing models using both 204 Pb- and 207 Pb-normalised Pb isotope ratios estimated sources' contributions as follows: i) municipal solid waste incinerator (at least 10 % in PM 10 and up to 60 % in both PM 2.5 and PM 1 ); ii) road traffic (up to 40 % for all size fractions); iii) coal-fired EGUs (around 20 % for all size fractions); and iv) geogenic particles (<10 % for all size fractions). Despite this strong contribution of anthropogenic sources, the potential health impacts of potentially toxic elements exposure were low, i.e., 3 additional cancer cases for adults per million of people due to Pb exposure, which nonetheless is comparable to levels observed in cities with populations 30 or more times larger than that of Tarragona. • Extremely severe metal enrichment in PM 1 during the cold season. • Enrichments in metals suggest a road traffic and waste incinerator origin. • Bayesian mixing models identified both anthropic (∼90 %) and geogenic contributions. • Potential health impacts due to Pb exposure as high as for larger cities. • First Pb isotope-based Bayesian models applied for PM 1 .