Critical review on atmospheric PAH. Assessment of reported data in the Mediterranean basin $ A.M. Mastral * , M.S. Calle ´n, J.M. Lo ´pez, R. Murillo, T. Garcı ´a, M.V. Navarro Instituto de Carboquı ´mica, CSIC, 50080 Saragossa, Spain Received 10 October 2002; received in revised form 31 October 2002; accepted 31 October 2002 Abstract Polycyclic aromatic hydrocarbons (PAH) are a special group of atmospheric contaminants included in the persistent toxic substances (PTS) and also in the volatile organic compounds (VOC) groups. PAH are present in the atmosphere and its origin can be due to anthropogenic and/or biogenic activities. Their specific characteristics, high volatility, mutagenic and/or carcinogenic power, easily transportable for long distances with the wind undergoing photodecomposition processes, which imply reactions with solar light, NO x and O 3 , make them important contaminants despite of the fact that they are present at very low concentrations. These characteristics make some of the PAH to be listed by the Environmental Protection Agency (EPA) as priority pollutants with negative environmental impact due to their toxicity and they can affect very negatively the living being due to their carcinogenic/mutagenic character. Because of atmospheric PAH properties, it is not worth to study them in small areas because they do not know about natural or political borders and they can affect to a huge population. The growing use of transport and energy consumption, PAH have mainly anthropogenic origin, joined the growing cancer incident, must be the alarm to take these toxic organic contaminants into account and under control. This paper is a revision on the reported data on atmospheric PAH in the Mediterranean basin and was shown at the Workshop of the United Nations Environmental Protection (UNEP), meeting held in Athens, February 2002. D 2002 Elsevier Science B.V. All rights reserved. Keywords: Organic atmospheric contaminants; PTS; VOC; PAH; Sampling; Detection; Quantification; Mediterranean basin 0378-3820/02/$ - see front matter D 2002 Elsevier Science B.V. All rights reserved. PII:S0378-3820(02)00249-7 $ Data shown at the Conference given at the UNEP meeting held in Athens, February 2002. * Corresponding author. Tel.: +34-976-733-977; fax: 34-976-733-318. E-mail address: amastral@carbon.icb.csic.es (A.M. Mastral). www.elsevier.com/locate/fuproc Fuel Processing Technology 80 (2003) 183– 193