Which tube is best for trace metal analysis?

The royal blue tube is specifically designed for trace metal analysis, making it the best choice in this scenario. These tubes are often used to collect blood specimens for toxicology and trace element testing, as they are manufactured with a minimal risk of contamination from trace elements. This is crucial because even small amounts of contamination from other tube materials can skew the results of trace metal testing.

In comparison, other tubes such as the plain red tube, green tube, and lavender tube may contain additives or be made from materials that could introduce trace elements into the sample, thus compromising the accuracy of the analysis. The royal blue tube, however, has been specially treated to ensure it does not leach these contaminants and remains suitable for the precise measurement of trace metals in the blood. Therefore, its use is essential for obtaining reliable results in trace metal testing.