Accumulation, Distribution, and Toxicity of Black Phosphorus Nanomaterials Across Biological Systems: A Critical Review

Abstract

Black phosphorus nanomaterials (BPNMs) composed of the essential element phosphorus-including nanosheets and quantum dots-have attracted growing interest due to their distinctive structure, tunable physicochemical properties, and broad applications in biomedicine, catalysis, and electronics. However, their environmental stability and potential toxicity necessitate a deeper exploration of interactions with biological systems. This review systematically summarizes the current understanding of BPNM accumulation, distribution, and toxicity across multiple biological systems, ranging from microorganisms and algae to fish and mammals. In aquatic species, BPNMs can adhere to cell surfaces, penetrate membranes, and induce oxidative stress, growth inhibition, and developmental defects. In mammals, they accumulate in major organs and tumor tissues via endocytosis, causing transient toxicity, oxidative stress, and inflammation. These biological behaviors are strongly influenced by size, concentration, surface modifications, and degradation. Despite progress, substantial gaps remain in understanding long-term impacts and molecular mechanisms of BPNMs with organism species, and their concentrations and critical environmental processes in real-world environment. We highlight key factors regulating biological interactions, discuss the roles of surface functionalization and degradation in mitigating risks, and propose future research priorities, including field-based measurements in environmental matrices, chronic exposure studies, health effects, and thus mechanistic elucidation. This review provides a comprehensive scientific basis for assessing the environmental and health risks of BPNMs and guiding their safe applications.