Outdoor air 1,3-butadiene monitoring near a petrochemical industry (Tarragona region) and in several Catalan urban areas using active multi-sorbent bed tubes and analysis through TD-GC/MS

Highlights: • 1,3-Butadiene was sampled in 12 Catalan urban areas from 2013 to 2017. • 1,3-Butadiene was sampled with multi-sorbent tubes and analysed by TD-GC/MS. • Urban areas near petrochemical facilities were the most impacted locations. • The other urban areas showed 1,3-butadiene concentrations around 1 μg m^{− 3}. • 1,3-Butadiene regulation should be implemented as soon as possible in Spain. 1,3-Butadiene is a carcinogenic compound that can be emitted to the atmosphere from several sources, such as the combustion of organic matter or traffic. However, petrochemical industry is one of the main origins of this compound. Several campaigns (2013–2017) were conducted in twelve Catalan urban areas to determine 1,3-butadiene concentrations in outdoor air, five of which were close to Tarragona petrochemical region. 1,3-Butadiene was dynamically sampled in multi-sorbent bed tubes (Carbotrap, Carbopack X and Carboxen 569) using portable pump equipment. The analysis was performed by automatic thermal desorption coupled with capillary gas chromatography/mass spectrometry detector. El Morell, Perafort and Puigdelfí, located near petrochemical facilities, were the most impacted locations, with average concentrations up to 15 ± 33, 33 ± 41 and 27 ± 39 μg m^{− 3}, respectively. Maximum 24 h concentrations of 125 μg m^{− 3} were observed in Puigdelfí. However, 1,3-butadiene average and maximum concentrations in the Tarragona petrochemical region diminished significantly (p ≤ 0.05) in a drastic way (40–80%) since the first monitoring program in 2013. On the other hand, average concentrations in the rest of studied Catalan urban areas generally presented average values below 1 μg m^{− 3}, ranging from 0.07–1.1 μg m^{− 3}. Spain does have neither a monitoring strategy nor standard regulations related to 1,3-butadiene. Taking into account that relevant values can be found in locations near petrochemical facilities, a regulation should be implemented as soon as possible, at least in this specific areas.