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A royal blue top tube is a blood collection tube with a royal blue closure, used for trace element and metals testing. The colour tells you the tube family, not the contents: royal blue tubes come with and without EDTA, so the test that was ordered decides which one to use. This page describes products and general use; it is not medical advice.
Who uses it: phlebotomists, laboratory staff and buyers who stock collection tubes, and students learning tube families.
What a royal blue top tube is
A royal blue top is an evacuated blood collection tube made for trace element testing, where the sample must not pick up metals from the tube itself. In the United States, blood collection tubes of this kind are regulated as Class 2 devices under product code JKA (“Tubes, Vials, Systems, Serum Separators, Blood Collection”), classification regulation 21 CFR 862.1675, in the Clinical Chemistry panel (openFDA classification database, data updated 2026-10-19).
Built to keep metals out
Kansas State Veterinary Diagnostic Laboratory (KSVDL) explains the reason for a dedicated tube: the rubber stoppers in other tubes may contain several minerals that can adversely affect trace mineral results. Manufacturers therefore sell separate trace element tubes. BD, for example, sells royal blue trace element tubes, and its 368381 tube has a BD Hemogard closure.
Types: EDTA and EDTA-free, same colour
KSVDL states that there are two types of royal blue trace mineral tubes: one contains EDTA and the other does not, and its panel requires the EDTA-free tube. The openFDA 510(k) record for BD names both a trace element K2EDTA tube and a trace element serum tube (K213953, decision 2023-07-17). So “royal blue” alone does not tell you the additive.
| Product | Additive | Size and volume | Source |
|---|---|---|---|
| BD Vacutainer Trace Element, cat. 367777, royal blue closure | K2EDTA 5.4 mg | 13 x 75 mm, 3.0 mL | BD customer letter BD-118946, 20 March 2024 |
| BD Vacutainer Specialty Tube, cat. 368381, royal blue Hemogard closure | K2EDTA 10.8 mg | 13 x 100 mm, 6 mL, plastic | BD product page 368381 |
| BD Vacutainer Trace Element Serum tube (the no-EDTA type) | Serum tube, no EDTA additive named | Models listed in the 510(k) record | openFDA 510(k) K213953 and K041071 |
Sizes that matter
The two BD EDTA tubes in the table differ in draw size (3.0 mL in 13 x 75 mm versus 6 mL in 13 x 100 mm) and in EDTA amount (5.4 mg versus 10.8 mg). BD’s 2024 letter reports that catalog 367777 is 510(k) cleared, has a 10-month shelf life, and was available to order from April 2024.
A dated change: lead-testing tubes
BD’s letter BD-118946 says catalog 367855, a K2EDTA 5.4 mg, 13 x 75 mm, 3.0 mL tube with a tan closure for lead testing, was discontinued effective 1 October 2024 and replaced by the royal blue catalog 367777 for multiple element testing. BD also added a fill indicator to the tube label in April 2024. A lab that used a tan lead tube will now see the replacement with a different closure colour.
How tubes are specified
- The additive is set by the test, not by the colour. KSVDL, for instance, specifies the EDTA-free royal blue tube for its trace mineral panel, and each performing laboratory publishes its own test directory.
- BD’s letter recommends following your institution’s policies and procedures for product validation prior to using a new tube.
Labels and handling basics
BD’s 2024 label update added a fill indicator to the tube label, described in the Instructions for Use, and put the electronic IFU web address on the case label. BD lists catalog 367777 with a 10-month shelf life. Collection, processing and shipping requirements are set by the laboratory that will run the test and by the manufacturer’s Instructions for Use.
Common mistakes
- Assuming the closure colour identifies the additive. Both EDTA and EDTA-free royal blue tubes exist.
- Treating a general-purpose tube as interchangeable with a trace element tube. Stoppers in other tubes may contain minerals that affect results (KSVDL).
- Assuming a colour name is universal. Names such as “navy blue top” are used informally and colour names vary, so tube identity is best confirmed by catalog number and the lab’s tube description rather than by the colour name.
FAQ
What is a royal blue top tube used for?
Trace element and metals testing, where the tube must not contribute metals to the sample. The exact test list is set by the performing laboratory.
Is a royal blue tube the same as a trace element tube?
Royal blue is the closure colour on BD’s trace element tubes. Whether the tube contains EDTA depends on the product.
Is a navy blue top tube the same thing?
Colour names vary. Confirm the tube by catalog number and the lab’s description.
See also the general guides to blood draw tube colors, the red top tube additive, the PST tube color and a phlebotomy lab supply checklist.
Sources
All sources checked 2026-10-30.
- BD, Vacutainer Specialty Tubes cat. 368381 product page: https://www.bd.com/en-us/products-and-solutions/products/product-print-page.368381
- BD customer letter BD-118946, Trace Element new SKU 367777, 20 March 2024: https://go.bd.com/rs/565-YXD-236/images/BD-118946%20Trace%20Element%20New%20SKU%20367777.pdf
- openFDA device classification, product code JKA (21 CFR 862.1675): https://api.fda.gov/device/classification.json?search=product_code:JKA; 510(k) K213953: https://api.fda.gov/device/510k.json?search=k_number:K213953; 510(k) K041071: https://api.fda.gov/device/510k.json?search=k_number:K041071 (data updated 2026-10-19)
- Kansas State Veterinary Diagnostic Laboratory, Trace mineral testing, April 2019: https://ksvdl.org/resources/news/diagnostic_insights_for_technicians/april2019/trace-mineral-testing.html
