The present disclosure provides a monitoring device comprising a test composition, a test element comprising a test portion to which the test composition is releasably adhered, a detection reagent, and a container comprising a first end with an opening and a second end opposite the first end. The test composition comprises a predetermined quantity of tracer analyte. The container is configured to receive the test portion and configured to be operationally coupled to an analytical instrument. The tracer analyte and the detection reagent each are capable of participating in one or more chemical reaction that results in the formation of a detectable product. A method of using the monitoring device to assess the efficacy of a washing process is also provided.