Influence of age on noise- and styrene-induced hearing loss in the Long-Evans rat

Two additional studies were performed controlling and examining the influence of body weight and post-natal age on the sensitivity to styrene. Rats of the same age (21 weeks) and but having different body weight (∼310 g versus ∼410 g) did not show any difference of sensitivity to 700 ppm styrene, whereas 14-week-old rats with the same body weight as 21-week-old rats (∼350 g) revealed increased sensitivity to styrene. These results show that weight does not play a key role in the sensitivity to styrene, and suggest a long period of increased sensitivity to styrene during the first months of life.