Benzene and non-Hodgkin's lymphoma

Incidence rates for non-Hodgkin's lymphoma (NHL) have been rising throughou t the world for several decades, and no convincing explanation exists for t he majority of this increase, The commonest subtypes of NHL have no well-de fined aetiological factors but lymphoma development has been linked with ex posure to a variety of chemicals, including nitrates, pesticides, herbicide s, and solvents, Benzene, a solvent and important constituent of petrochemi cal products, is a potent lymphomagen in experimental animals and high-dose exposure in humans is associated with both acute myeloid leukaemia and NHL . Much current interest centres on the possibility that environmental benze ne exposure in the general public may underlie a proportion of the increase in NHL, Seventy per cent of benzene exposure in the environment is derived from vehicle exhaust emissions, whose increase has closely paralleled the rise in frequency of the disease, Mathematical modelling has been used to c alculate an acceptable concentration of benzene in air based on risk estima tes derived from industrial exposure, but the recommended target concentrat ion in the U.K. of 1 ppb is regularly exceeded in urban locations. Detailed investigation of the health effects of low-level benzene exposure awaits a n accurate assay for quantifying long-term human exposure, The P-32 post-la belling technique for the detection of toxin-specific DNA adducts is extrem ely sensitive and has been applied in the biomonitoring of exposure to a nu mber of carcinogens, but benzene-DNA adducts have to date proved elusive of detection, Copyright (C) 1999 John Wiley & Sons, Ltd.