Plastic storage tubes are used in laboratories worldwide to store biological and chemical samples. As most plastics are supplied sterile, pyrogen- and DNAse/RNAse-free, it is generally accepted that this guarantees product integrity. Few researchers ever consider that despite these apparent guarantees, plastic ware can still provide a potential source of error. Evidence shows that bioactive compounds can diffuse into solutions that come into contact with the surface of the plastic 1,2. These compounds, typically referred to as “leachables” or “extractables”, are used during the manufacturing process to improve product stability and durability. However, these compounds can have a significant impact on scientific experiments and pose a likely source of error in many assay systems. Examples of leachable interference include inhibition of enzyme activity and falsification of nucleic acid quantification. The aim of this evaluation was to determine if “extractables” could be detected in solvent solutions stored in FluidX external thread tubes and to compare the performance against competitor tubes.