Does the Gas Senor V2 Consume Gas?

I’m using the Grove Gas Sensor V2 (Multichannel) in a small area of volume, and I’ve noticed that all measured gasses are dropping over the several days. I need to figure out if this is real, or is the sensor actually reacting with the gasses and consuming it?

Hello, They work through sensing electrodes in the air, spending an electric current to sound the alarm. Catalytic bead: using a platinum-treated wire coil, this type of gas detector most commonly identifies combustible gas in the air as the coil oxidises upon contact with the gas, tripping an alarm.

I don’t think it is unusual. Because the gas concentration may be different on different days, at the same place. You can run some tests. Just blow a candle or burn a matchstick right in front of the sensor. Also try alcoholic sources like nail polish, nail polish remover, mouth wash etc. If you see some of the values showing a big change in presence of these, you can be sure that the sensor is working.
I can see that you’ve chosen a 4 in 1 gas sensor. If you are interested in testing your environment with something simpler, you can take a look here: Gas leak detector alarm system with arduino nano - Share Project - PCBWay