Exceptional points (EPs) and bound states in the continuum (BICs) are two distinct types of optical singularities that have attracted significant attention for their potential. While EPs are known for their enhanced sensitivity to perturbations, their performance in passive resonator systems is often limited by radiation losses. Conversely, BICs are ideal nonradiating resonances with theoretically infinite Q factors. Here, we explore the interplay between these singularities under time-reversal $\mathcal{T}$ symmetry breaking. We demonstrate the realization of an EP by merging two symmetry-protected BICs corresponding to the $E_2$ representation in a $C_{6v}$-symmetric photonic crystal slab composed of magneto-optical material. By applying an external magnetic field, we introduce an additional mechanism to break $\mathcal{T}$ symmetry, which competes with the intrinsic radiation losses of the open system. Our simulations show that the two BICs coalesce at the $\mathrm{\Gamma }$ point, forming an EP. This work unveils the interaction between different forms of $\mathcal{T}$ symmetry breaking and provides a controllable pathway for dynamically inducing EPs from BICs with infinite Q factors, with potential implications for sensing and tunable photonic devices.

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• Bound states in the continuum
• Nanophotonics
• Exceptional points
• Non-Hermitian systems