8000020 Exposure of asphalt workers paving with different types of polymer modified bitumen (PMB) asphalts including a new bio-asphalt

<h3>Objective</h3> Asphalt used on roads is a complex mixture of chemicals that may cause different adverse health effects for the pavers. Due to increased focus on climate changes the content is rapidly changing from traditional petroleum-based asphalts to types made of renewable materials like plant-based oils. Additives to lower the production temperatures are now common, but new information about the exposure and health effects of these is limited and important to assess. <h3>Material and Methods</h3> Whole shift personal exposure of pavers, screed men, material transfer vehicle (MTV)/Shuttle buggy operators, roller and tractor operators and others paving with PMB asphalt at different temperatures are measured regarding respirable and total dust, asphalt smoke, organic (OC) and elemental carbon (EC), nitrogen dioxide (NO2) during three seasons from 2021-2023 in the Norwegian capitol and its surroundings. <h3>Results</h3> The median respirable dust exposure was 0.13, 0.15, 0.07, 0.03 and 0.08 mg/m3 for paver operators, screed men, material transfer vehicle operators, roller/tractor drivers, and other workers respectively. Their total dust exposure was 0.21, 0.26, 0.15, 0.09, 0.10 mg/m3, while the OC concentrations were 0.24, 0.21, 0.17, 0.08, 0.14 mg/m3. The asphalt smoke exposure was 0.04, 0.05, 0.04, 0.01, 0. 0.01 mg/m3. Nor negligible amounts of EC were detected and NO2 was mainly found during paving in tunnels. High asphalt temperatures generally result in more exposure than at lower temperatures, with the bio-oil giving the lowest exposure. <h3>Conclusion</h3> Lowering the temperature and adding bio-oil seems to decrease the exposure when paving with these PMB asphalts.