Work on deck on eight oil product tankers was examined. The purpose was to evaluate the need for improvement of the working environment to reduce the risk of occupational cancer. Benzene, polyaromatic hydrocarbons (PAHs) and organic lead compounds were sampled, and the crew answered a questionnaire on acute health effects. By area monitoring, benzene was generally found to be in the range from the detection limit, of 0.01 ppm, up to 1.15 ppm, but one tanker which loaded gasoline with the hatches open had levels up to 55 ppm. Personal monitoring showed exposure levels in the range 0.01-1.15 ppm. The PAH-levels and the levels of organic lead were low. No seamen were observed using respiratory protective equipment. Central nervous system symptoms were reported by the crew with the highest exposures to benzene although benzene may not be the only cause. The exposure to benzene and other hydrocarbons on the deck of oil product tankers ought to be reduced.
Exposure of the deck crew to volatile hydrocarbon compounds and polycyclic aromatic hydrocarbon PAH compounds was observed and monitored on two Norwegian product tankers. The tankers were loading their cargo with the hatches open during the monitoring period. One of the tankers loaded gas oil. This type of cargo is not volatile, and very low concentrations of the monitored chemical PAH compounds were found on this tanker. The second tanker loaded gasoline. On this tanker high concentrations of hydrocarbon compounds were found; benzene was as high as 55 ppm, toluene was as high as 34 ppm, hydrocarbon compounds in the C5-C7 range were as high as 570 ppm, n-hexane was as high as 25 ppm. The levels of PAH-compounds were low. None of the seamen working on the deck did use respiratory protective equipment during the work. The exposure of the deck crew to volatile hydrocarbon compounds ought to be reduced on product tankers. Better routines concerning the use of respiratory protective equipment is an immediate action which ought to take place. Loading volatile cargo like gasoline with the hatches open should be avoided.