Wearable alcohol monitoring device

A wrist-worn device for monitoring alcohol consumption, the wrist-worn device comprising:

• a device housing comprising:
• an upper housing;
• a lower housing having a top wall and a circumferential side wall, the top wall defining a first access opening, the lower housing attached to the upper housing;
• and
• a wrist piece having a first face and a second face, the wrist piece defining a trench in the first face that protrudes from the second face as a closed curve-shaped protrusion, the closed curve-shaped protrusion configured to fit on a subject's wrist surface such that the closed curve-shaped protrusion presses into a subject's skin to form a liquid and vapor seal inhibiting transdermally emitted ethanol from escaping outside a collection area, the lower housing and the wrist piece cooperatively forming an amplification chamber, the amplification chamber being a cavity below the top wall of the lower housing and above the wrist piece, wherein the wrist piece defines a plurality of vent holes that allow transdermally emitted ethanol to enter the amplification chamber;
• an electrochemical sensor for ethanol having an electrode aligning to the first access opening;
• control circuitry enclosed in the upper housing, the control circuitry configured to receive measurements from the electrochemical sensor and to calculate transdermal alcohol concentration;
• and
• a water-absorbing material sequestered in the amplification chamber, including in the trench.