To quantify the effects of multiple physico-chemical stressors on the metabolism of single cells, this project combines microfluidic technology and quantitative phase imaging (QPI) into a novel high-throughput ‘Ecotoxicology-on-a-chip’ approach. The developed image analysis pipeline will enable us to determine growth rates and cell dry mass of marine bacteria on a single-cell level and thus, improve ecotoxicological predictions regarding pollutant effects in aquatic ecosystems.