Materials with stereochemically active lone pair electrons have recently attracted interest as potential thermoelectric materials. This is mainly due to their anomalously low thermal conductivity linked to the lone pair electrons related to the creation of a strong local bonding asymmetry responsible for enhanced phonon anharmonicity. Most efforts on this subject have focused on the investigation of tetrahedrites based on the composition Cu12Sb4S13, but so far no clear understanding on the interactions of the lone pair electrons and of the microscopic mechanism responsible for enhanced anharmonicity has been reached. Using E9 and KMC2, we propose to study the crystal structure of a very recently proposed lone pair system, Bi2PdO4, and to determine the temperature dependence of its atomic displacement parameters which can be understood as signature of anharmonic phonon interactions.