This study investigated the relationship between maternal behaviours, environmental exposures, and the levels of melamine and bisphenols (BPs), including bisphenol F (BPF), bisphenol A-F (BPAF), and bisphenol S (BPS), in breast milk. Mothers provided information on cosmetic use, food packaging, and dietary habits, while breast milk samples were analyzed using high-performance liquid chromatography. BPAF, BPS, and BPF were detected in 32.3%, 33.8%, and 20% of samples, respectively, while melamine was present in all samples (mean: 32.3 ± 16.7 ng/mL). Seven samples (10.8%) contained all three BPs, while 49.2% had none. Higher BPAF and BPF levels were observed in breast milk from mothers aged 30–34. Makeup use was associated with elevated BPAF levels (p = 0.013), while sunscreen use was correlated with increased BPF (p = 0.040) and melamine (p = 0.010) levels. Storing oil in plastic containers was linked to higher BPS levels. These findings suggest that maternal exposure to personal care products and food packaging materials significantly influences BPs and melamine levels in breast milk. The results highlight the importance of considering both behavioural and environmental factors when assessing chemical exposure during breastfeeding. Further research is needed to understand the long-term effects of these exposures on infant health.