Mechanism of uptake, accumulation, transport, metabolism and phytotoxic effects of pharmaceuticals and personal care products within plants: A review

Pharmaceuticals and personal care products (PPCPs) ubiquitously occur in the environment, resulting in detrimental effects on human health and other organisms. With the application of compost, manure and biosolids and the reclamation of treated wastewater, PPCP contaminants are introduced into the terrestrial and aquatic environments, giving rise to potential accumulation in plants. As PPCPs represent a range of chemicals with diversified physicochemical properties, their uptake and bioaccumulation in the plant show great differences, which have drawn increasing attention from both research communities and the general public in recent years. To date, there are few quantitative assessments of the potential of plants to take up and translocate PPCPs, and available data on metabolism of PPCPs are also limited. Therefore, by assembling the literature, this review summarizes the uptake and accumulation pattern of PPCPs within plants, and explicitly clarifies the plant uptake and translocation processes from the perspective of the root and foliar uptake, short-distance and long-distance transport. The main factors influencing the uptake and transfer of PPCPs are also shed light on in this review. These factors include chemical hydrophobicity, ionization properties, pH, molecular size, lipid and carbohydrate content, transpiration rates, etc. Furthermore, related enzymes, transformation products and the role of plant-bacteria partnership in the metabolic process are elucidated. Moreover, the plant development, physiological and biochemical responses to the exposure to the PPCPs are summarized. Finally, on the basis of the results presented, research gap areas and questions have been also identified with future perspectives. Overall, this paper presents information for a more comprehensive understanding of the uptake, accumulation, translocation and metabolism of PPCPs in plants, and could be a valuable guideline to the key physiological and biochemical process of PPCPs from entering the plant and their phytotoxicity when assessing the risk of PPCPs.