Saeder-Krupp Trinket

The Trinket! is a wide-bore metal drinking straw with a chemical contact sensor, available for 50ny. Upon being inserted into water or alcohol, after ten seconds it verifies the absence of harmful bio-organisms, methanol or other moonshine byproducts, conventional GHB derivatives, scopolamine, arsenic, strychnine, or cyanide. It indicates this by a chemical-activated band at the top rim of the straw: green for safe, red for unsafe. After roughly 1500 beverages or 6 months, the band will turn yellow-brown, indicating the end of its operational lifespan.

The Trinket! has two known bugs: it rates all milk as unsafe to drink and all nonalcoholic juices as safe to drink, and contact with substances more acidic than water (including milk and most fruit juice) degrades its store of chemicals more rapidly.

While not a bug, it is notable that the Trinket! has no means of detecting any toxin other than those listed above. It also has no way of distinguishing between toxins - the 'red' is exactly the same for a superdose of cyanide as it is for traces of harmless algae in water.