Analog Alcohol Sensor MQ3
This MQ3 gas sensor is sensitive to different gasses but is most sensitive to alcohol with a detecting concentration from 0.04mg/L to 4mg/L. This module is compatible with the 5v power supply.
It has 4 pins (Digital Pin, Analog Pin, VCC, GND), but needs three (either D or A) to interface this to your Arduino.
You may integrate this module with different projects that have alcohol presence monitoring in it. Or a breathalyzer to check if a person is intoxicated with alcohol.