Figure 1.

The flame retardant (FR) mixture Firemaster 550 (FM 550) induces long-term bone loss in the femur trabecular bone of male but not female rats as demonstrated by decreased bone microarchitecture. (A) Representative micro computed-tomography (microCT) images of female (left) and male (right) rats from Control and exposed to FM 550 groups. Longitudinal (top) and transversal (bottom) views of the femur are shown. Red arrows indicate the metaphysis region in which bone parameters were analyzed; (B) Mean ± standard error of the mean (SEM) of bone mineral density (BMD; g/cm⁻³), percent bone volume/tissue volume (BV/TV; %), bone volume (BV; µm³), structural model index (SMI), trabecular thickness (Tb.Th; µm), trabecular number (Tb.N; 1/µm), and trabecular separation (Tb.Sp; µm). Two-way ANOVA followed by the Holm–Sidak post hoc test (n = 4 per group). * p < 0.05 different from control of same sex; # p < 0.05 different from exposed females, ## p < 0.01 different from exposed females.