Environmental versus dietary exposure to POPs and metals: A probabilistic assessment of human health risks† Victoria Linares, ab Gemma Perell o, a Martı ´ Nadal, a Jes us G omez-Catal an, c Juan M. Llobet c and Jos e L. Domingo * a Received 23rd July 2009, Accepted 5th November 2009 First published as an Advance Article on the web 23rd December 2009 DOI: 10.1039/b914962g The human health risks derived from the multipathway/multipollutant exposure to various chemicals were assessed in an area with significant petrochemical activity (Tarragona, Catalonia, Spain). Environmental exposure to several Persistent Organic Pollutants (POPs) (PCDD/Fs, PCBs, PCNs, and PAHs) and metals (As, Cd, Cr, Hg, Mn, Pb, and V) was determined and compared with the dietary intake of these pollutants. The mean environmental exposure to organic pollutants ranged from 6.36  10 6 ng WHO-TEQ kg 1 day 1 to 3.34 ng kg 1 day 1 for PCDD/Fs and PAHs, respectively. In turn, the minimum and maximum values of environmental exposure to metals corresponded to Cd (9.35  10 8 mg kg 1 day 1 ) and Mn (8.72  10 5 mg kg 1 day 1 ), respectively. Among the environmental exposure pathways, dermal absorption and soil ingestion were the most important pathways for POPs and metals, respectively. However, this exposure was notably lower than the dietary intake of these contaminants, with percentages of <2% for most of them. Considering cumulative effects, the current concentrations of micropollutants do not mean significant additional non- carcinogenic and carcinogenic human health risks. Notwithstanding, in order to consider the synergistic/antagonistic effects according to the target organ or mode-of-action, the development of alternative methodologies of risk assessment are necessary for a more accurate evaluation. Introduction Chemical and petrochemical industries are responsible of the emissions of inorganic gasses such as SO 2 , NO x ,H 2 S and CO, particulate matter, as well as a series of micropollutants. Among these, particular attention has been paid to heavy metals and Persistent Organic Pollutants (POPs) such as polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) and poly- chlorinated biphenyls (PCBs). Moreover, traffic has also been pointed out as an important emission source of some of these contaminants, to which polycyclic aromatic hydrocarbons (PAHs) and lead (Pb) can be included. 1–4 Humans are exposed to environmental metals and POPs through various pathways (i.e., inhalation and ingestion). However, it is well established that diet is the main route of entrance to the human body of these contaminants, accounting for more than 90% of total exposure. 5–7 Notwithstanding, most dietary studies are focused on single contaminants, rather than mixtures of pollutants. Therefore, integral/overall investigations to evaluate the human health risks derived from multipollutant and multipathway exposure are not particularly common. 8,9 One of the most important petrochemical complexes in southern Europe is located in Tarragona County (Catalonia, Spain). A broad spectrum of industrial facilities, including a big oil a Laboratory of Toxicology and Environmental Health, School of Medicine, IISPV, ‘‘Rovira i Virgili’’ University, Sant Llorenc ¸ 21, 43201 Reus, Catalonia, Spain. E-mail: joseluis.domingo@urv.cat; Fax: (+34) 977- 759322; Tel: (+34) 977-759380 b Physiology Unit, School of Medicine, ‘‘Rovira i Virgili’’ University, Sant Llorenc ¸ 21, 43201 Reus, Catalonia, Spain c GRET-CERETOX, School of Pharmacy, Department of Public Health, University of Barcelona, Avgda. Joan XXIII s/n, 08028 Barcelona, Catalonia, Spain † Electronic supplementary information (ESI) available: Monte-Carlo parameter distributions (Table S1); Parameters for calculation of non-carcinogenic and carcinogenic risks (Table S2); Exposure evaluation for children (Table S3). See DOI: 10.1039/b914962g Environmental impact Humans are exposed to pollutants through various pathways, diet being the most important contributor. Most studies are generally focused on single contaminants, rather than mixtures of pollutants. Therefore, overall investigations focused on evaluating human health risks derived from multipollutant and multipathway exposure are not particularly frequent. In this study, the cumulative environmental exposure to several Persistent Organic Pollutants and metals for the population of Tarragona (Catalonia, Spain) was determined and compared with the dietary intake of these pollutants. The human health risks following multipollutant/multi- pathway exposure to chemical pollution were assessed. The results should contribute to enhance the information regarding the health risks of environmental pollutants in more realistic scenarios. This journal is ª The Royal Society of Chemistry 2010 J. Environ. Monit., 2010, 12, 681–688 | 681 PAPER www.rsc.org/jem | Journal of Environmental Monitoring