Boston startup dives into marijuana industry with high-tech sensor to weed out impurities

The compact mass spectrometer shows precisely what’s in marijuana.

The compact, high-tech chemical sensors made by the Boston startup 908 Devices are used by emergency responders to scan for toxins after industrial accidents, and by researchers in the pharmaceutical and energy industries to profile the composition of drugs and petroleum products.

Now, the firm has unveiled a new sensor intended to give it a foothold in a less conventional but fast-growing industry: commercial marijuana.