Green’s Dictionary of Slang

Bay State n.

[proprietory name]

(US drugs) a hypodermic syringe.

[US]D. Maurer ‘Argot of the Und. Narcotic Addict’ Pt 1 in AS XI:2 118/1: bay state. A hypodermic needle.
[US]Anslinger & Tompkins Traffic In Narcotics 303: bay state. A hypodermic needle.
[UK]J. Morton Lowspeak.