Trace Metals: Using Blue HDPE Containers
George received some low trace metals material that was delivered in a blue HDPE container. Eventually, he planned to transfer it to a LDPE container. George wanted to know what was considered "short-term storage" in HDPE and what specific contaminates the blue coloring might contain.
All of the blue pigments I am familiar with contain copper combined with a combination of an organic ligand and maybe an inorganic ligand to modify the shade of blue. A point of interest — there were over 700 different shades of blue available during the time of the American Revoultion.
I do not have a definition for short-term exposure unless I have an understanding of the leaching curve of the contaminant of concern. If your sample is non-acidic and relatively inert, it is unlikely that a blue pigment will readily leach. Pigments in general are chemically unreactive. Therefore, in this case a short exposure could be as long as a day or more. If the sample is polar (not wetting the container) and neither caustic or acidic (pH between 4 and 10), you should be okay. However, you may want to encourage your co-workers to consult with you before they collect a sample. It is to their benefit as well as to yours that they consult with you before starting a project requiring trace analysis.
Please contact me with any other concerns. I'd be happy to help.
Serving you in chemistry,
Paul R. Gaines, Ph.D.
CEO of Inorganic Ventures & Fellow Chemist
DISCLAIMER: Advice offered by the chemists at Inorganic Ventures is intended for the individual posing the question. Feel free to contact us to verify whether these suggestions apply to your unique circumstances.