Seems possible.

The linked-to article in turn links to https://indianapublicmedia.org/news/indiana-man-training-k9-... dated January 27, 2017 describing how ""I had to pay a chemist to actually find the actual odor," Jordan says. "So it's an odor that's within the actual SD cards, the thumb drives, cell phones.""

This is further detailed at https://www.techrepublic.com/article/electronics-sniffing-do... where "[Dr. Jack] Hubball examined hard drives, thumb drives, SD drives–every type of electronic storage device available. The common denominator? A circuit board."

> He began testing various circuit board components, and about six months later, identified a compound called triphenylphosphine oxide (TPPO)–which covers the circuit boards in all storage devices from large hard drives down to microSD cards to keep them from overheating.

> Another compound, hydroxycyclohexyl phenyl ketone (HPK), was extracted from removable media, such as CDs, DVDs, Blu-Rays, and even floppy disks.

(There are similar accounts about this Connecticut State Police work, like https://www.akc.org/expert-advice/news/can-dogs-detect-cyber... .)

I then tried to figure out how well established this is outside of this one Connecticut example. A Google Scholar search finds a paper from Italy at https://pubblicazioni.unicam.it/bitstream/11581/452666/1/69-... says:

> Dogs trained to sniff electronic equipment are the least known specialization of canine training, which has been implemented after the 9/11 terrorist attacks. International Police Forces begun to train search dogs for the retrieval of electronic equipment such as USB sticks, micro SIM cards, mobile phones, DVDs, CD-ROMs, external hard drives, and memory cards. Specialized dog units in this sector are called Electronic Storage Detection Dogs (ESDD) [24]. The ESDD dog is trained to sniff out the chemical component, triphenylphosphine oxide (TPPO), common to most electronic gadgets and storage devices, as a thermal insulator [25].

[24] is https://onlinelibrary.wiley.com/doi/pdf/10.1111/1556-4029.13... from 2017:

> Analyses found several volatile compounds common to SIM and SD cards, as well as USB drives, including 2-propenenitrile, styrene, isophorone, hydroxycyclohexyl phenyl ketone, and 2-furanmethanol, tetrahydro. Results indicated that mass storage devices do have a characteristic odor profile making detection with minimal false alerts feasible for trained canines.

Note: this is a feasibility study only - it does not test if dogs could do it. Nor does it mention the TTPO mentioned in the Italy paper, which is also not mentioned in [25] -- which had nothing to do the the topic!; see

[25] is https://www.researchgate.net/profile/Jorge-Rojas-11/publicat...

The Italy paper's [26] is also messed up.

Another lead is https://www.taylorfrancis.com/chapters/edit/10.1201/97810032... "This chapter introduces the project within the National Police of The Netherlands and focuses on the training method used for “Digital Storage Device Dogs.” Canines have previously shown to be an effective tool in locating obscured digital storage devices in the United States and United Kingdom." I don't have access to the content.

A news blurb about the UK use is at https://ieeexplore.ieee.org/document/8401991 but does not include what substance is detected. It does say the dogs used in the project came out of the Connecticut State Police work.

I would like to know of dogs which have been trained for this task which did not come out of that one program, and/or learn more about the specific tests done under more rigorous circumstances than the ones described in the links I gave.

Still, it does seem feasible that it works as described.