Effect of chronic mixed pesticide exposure on peripheral and autonomic nerve function.

In a cross-sectional study involving 131 flower bulb farmers (mean age = 43 y) and 67 well-matched controls, peripheral and autonomic nerve functions were examined. The study group had been exposed during a period of 20 y (standard deviation = 7) and applied a similar pesticide package. Lifetime cumulative exposure was estimated based on exposure levels for specific application methods and duration of exposure. Exposure-related decreased conduction velocities were found in the motor fibers of the median (-1.1 m/s) and peroneal (fast fibers: -1.2 m/s, slow fibers: -1.3 m/s) nerves, and in the sensory fibers of the median (-1.4 m/s) and sural (-0.9 m/s) nerves. In addition, the refractory period was determined and found to be increased in the sural and peroneal nerves. With regard to the autonomic nerve function, a decrease was found in resting sinus arrhythmia (-10%).