Nanoparticles (NPs) have been progressively applied in the last decades, which may impact the environment. Synthesis of pigments and nutrient elements uptake by plants can also be affected by NPs. The in uence of lanthanum oxide nanoparticles (La 2 O 3 NPs) on growth, pigments synthesis and nutrient elements uptake by Pfa a glomerata (Spreng.) Pedersen, a medicinal plant native in South America, were evaluated in the present study. P. glomerata plantlets were cultivated for 28 days in the absence (control) and presence of 100, 200 and 400 mg L −1 of La 2 O 3 NPs or bulk-La 2 O 3 (b-La 2 O 3 ) at the same cultivation conditions. Root development, aerial part growth and pigments concentration in plants were affected by b-La 2 O 3 and La 2 O 3 NPs, mainly by La 2 O 3 NPs. Calcium, Cu, Fe, K, La, Mg, Mn, Mo, P, S and Zn determination in stems and leaves revealed drastically and similar decrease of nutrient elements in plants cultivated in presence of 400 mg L −1 of La 2 O 3 NPs or b-La 2 O 3 . Alteration of nutrient elements concentration was also observed for the other treatments. Mapping of elements (using laser ablation inductively coupled plasma mass spectrometry) in leaves of plants submitted to treatment with 400 mg L −1 of b-La 2 O 3 or La 2 O 3 NPs showed differences in the distribution of elements, indicating distinct effects of b-La 2 O 3 and La 2 O 3 NPs on P. glomerata. As such, this study demonstrated that La 2 O 3 NPs may impact plants growth. Highlights Metal nanoparticles are of increasing use and are of environmental concern La 2 O 3 affect growth, pigment synthesis and nutrient elements in Pfa aglomerata Changes of nutrient distribution is observed in leaves of Pfa aglomerata Instrumental parameters of the ICP OES, ICP-MS and LA instruments