Drug delivery to the central nervous system (CNS) represents one of the most priority challenges in research and development of pharmaceutical nanotechnology products. Among the various non-invasive approaches for CNS delivery, nanoparticle carriers and particularly polymeric nanoparticles (PNs) seem to be one of the most interesting. This review deals with PNs as CNS drug delivery systems and their potential endocrine disrupting properties. Possible interference with the development of neuroendocrine-reproductive system is considered. Special regard is being paid to potential mechanisms of PNs toxicity. Necessity to investigate the toxicity of nanomaterials and their impact on human health are discussed.