909 Biological monitoring of benzene after exposure to fresh crude oil spilled at sea in an oil spill field trial

Introduction Oil spill cleanup personnel could be exposed to benzene during cleanup of accidental spill of crude oil at sea. S-Phenyl Mercapturic Acid (SPMA) is reported to be a sensitive urinary marker of exposure to low levels of benzene, but there is a lack of information on biological uptake of benzene during cleanup of oil spills. The aim of this study was to investigate the exposure to benzene during an oil spill by measuring the concentration of SPMA in urine for subjects participating in an oil spill field trial at sea. Methods The study included 22 subjects taking part in an oil spill field trial in the North Sea with two types of fresh crude oil. The subjects were located in open air sampling boats close to the oil slick ( Results SPMA was not detected in the urine samples of subjects wearing protective masks and in the control group. Among the six subjects who reported not to wear protective masks during the spill the concentration of SPMA in urine ranged 0.5–3.3 µmol/mol. They were all located in the boat closest to the oil spill. Discussion We have previously reported that mean personal exposure to benzene in air was 0.43 ppm for the personnel in the boat closest to the oil spill. The present study suggests that work with fresh oil spilled at sea might cause biological uptake of benzene. Appropriate personal respiratory protection should be used to prevent such uptake.