Increased risk of sensory neuropathy in workers with chloracne after exposure to 2,3,7,8-polychlorinated dioxins and furans

Objective - The existence of a peripheral neuropathy after exposure to poly chlorinated dioxins (PCDD) is still discussed, as studies concerning dioxin effects on the peripheral nervous system are rare and contradictory. Mater ial and methods - Clinical and neurophysiological examinations (motor condu ction velocity of the peroneal nerve, sensory conduction velocities of the sural and ulnar nerves) were made in 156 dioxin exposed workers (42 with, 1 14 without cloracne) from one pesticide producing plant. Because of known r isk factors for peripheral neuropathy, 7 workers with and 28 without clorac ne were excluded from further analysis. Results - Workers with chloracne ha d a significantly higher exposure against PCDD as documented by back calcul ated lipid levels. They complained significantly more often of sexual impot ence (28.6% compared to 5.8% of workers without chloracne, P<0.001), had si gnificantly more frequent clinical signs of a sensory neuropathy (= abnorma l sensory findings plus deep tendon reflex abnormalities) restricted to the legs (17.1% compared to 1.2%, P<0.001), had significantly more frequent gr eater than or equal to 2 neurophysiologic abnormalities (34.3% compared to 14.0%, P<0.025), and had significantly lower mean amplitudes of the motor c ompound muscle potential of the peroneal nerve. Conclusion - PCDD has a mil d toxic effect on the peripheral nervous system manifesting as mild sensory neuropathy of the legs in a minority of the most severely exposed persons.