Third-party performance assessment data encompassing the time period of analysis of groundwater samples collected for hormones and pharmaceuticals by the National Water-Quality Assessment Project in 2013-15

This data set includes sample information and results for third-party performance assessment samples analyzed for hormones and pharmaceuticals during the same general time period as environmental samples collected by the National Water-Quality Assessment (NAWQA) Project for a study of groundwater resources used for drinking-water supply across the United States, 2013 through 2015. Hormone and pharmaceutical results are provided for spiked and unspiked samples submitted by the Quality Systems Branch (QSB) Organic Blind Sample Project (OBSP), providing information regarding analyte recovery and occurrence of false positive and false negative results. Included in this data release are the following data tables: Table 1. Hormone results for third-party performance assessment samples submitted by the Quality Systems Branch Organic Blind Sample Project for analysis by the National Water Quality Laboratory, December 14, 2012 through March 7, 2016. Table 2. Pharmaceutical results for third-party performance assessment samples submitted by the Quality Systems Branch Organic Blind Sample Project for analysis by the National Water Quality Laboratory, December 14, 2012 through March 7, 2016.