Determination of LOD and LOQ Values for PCBs and Dieldrin in Water

Abstract

The relative response factor is the slope of a plot of the response ratio (Area of Congener/Area of IS) along the y axis vs a concentration ratio (ng of congener/ng of IS) along the x-axis. If this plot is linear, then the RRF is a constant. However if the plot shows curvature such that a quadratic equation (as shown below), is needed to fit the data, then the RRF is not constant but can be evaluated at any point along the x-axis from the slope of the curve.