The use of sedentary bioindicators, such as trees, in environmental contamination monitoring is receiving increased focus. This study evaluates Theobroma cacao L. as a bioindicator for cadmium (Cd) contamination by quantifying hydrogen peroxide (H₂O₂) as an oxidative stress marker in cellular suspensions exposed to CdSO₄. Chronoamperometric measurements using platinum electrodes indicated Cd accumulation in T. cacao L. and revealed a corresponding increase in H₂O₂ production up to a threshold level, beyond which cell apoptosis occurred. These findings support the potential of T. cacao L. as a bioindicator of Cd pollution. Moreover, H₂O₂ quantification via chronoamperometry demonstrated a rapid and effective method for detecting Cd-induced oxidative stress in plant systems. Future research should explore field applications, evaluate alternative plant species, and assess long-term responses under real environmental conditions to optimize this approach for large-scale biomonitoring.