Figure 3

Accuracy of uBPA and BPA-G measurements in five spiked samples from Phase 2. A) Results reported for uBPA measurements in spiked samples by four participating laboratories. Each graph (top to bottom) represents the data from an individual spiked sample ranging from the lowest concentration (0.5 ng/ml) to the highest concentration (19.5 ng/ml). B) Results reported for BPA-G measurements in spiked samples by four participating laboratories. Each graph (top to bottom) represents the data from an individual spiked sample ranging from the lowest concentration (0.5 ng/ml) to the highest concentration (19.5 ng/ml). In both panels, graphs represent mean ± standard deviations reported from each laboratory. The red line marks the actual concentration spiked and the yellow bar marks the range of ±20%. At the bottom of each panel is the performance summary for each laboratory for Phase 2 for uBPA (A) and BPA-G (B). A method was considered “verified” for the phase when at least 4 of 5 spiked samples measured concentrations within 20% of the actual spiked amount.