Analysis of the occurrence and risk assessment of polar pesticides in the Llobregat River Basin (NE Spain)

► This work is one of the first to assess the environmental risk of pesticides in the Llobregat River. ► It applies for the first time in Spain the PRISW-1 risk to pesticides in surface waters. ► Sampling as performed allowed establishing spatial and temporal variations in pesticides levels. ► Pesticides levels and hydrological conditions were jointly handled in terms of mass loads. ► The PRISW-1 index is a useful tool to evaluate the chemical and ecological status of a river.