Buro VERHAAR is Henk Verhaar’s consultancy business. Henk Verhaar obtained a PhD in 1995, defending a thesis about the use of QSARs to predict the toxicity of organic pollutants to aquatic organisms, and presenting a classification system for pollutants that has found widespread use in the evaluation of new and existing chemical substances. After obtaining his doctorate and spending time as a visiting assistant professor at Colorado State University, where he expanded his skills to PBPK-modelling, in 1998 Henk switched from academia to consultancy, working first at OpdenKamp Adviesgroep and subsequently at ENVIRON corporation, helping Dutch and international businesses with the registration of chemical substances, first and foremost plant protection products and biocidal products. Late 2013 Henk joined a small company developing novel disinfectant products, where he was active in both product development and registration. Currently he is back as independent consultant in the field of evaluation and authorization of chemical substances, with a strong focus on physical and chemical properties, fate and behaviour of substances in the environment, and ecotoxicology. Working closely with former colleagues in the fields of human toxicology and ecotoxicology, Buro VERHAAR can help you with all aspects of authorization of chemical substances, plant protection products and biocidal products, including the development of complete registration dossiers. Buro VERHAAR specializes in solving out-of-the-ordinary problems.