'New software warns if mixing any two chemicals is dangerous'

Scientists have developed a new free-to-use software which can warn users if it is unsafe to mix certain chemicals, an advance that can prevent fires, explosions, and injuries in laboratories, and homes due to improperly mixed chemicals.

The software, called ChemStor, is described in the Journal of Chemical Information and Modeling, and draws from the US Environmental Protection Agency's (EPA) archive of 9,800 chemicals, organised based on how they react.

To build the software, engineers from the University of California (UC) Riverside in the US, adapted a computer science strategy to allocate resources for efficient processor use, known as graph colouring register allocation.

In this system, they said, the resources are coloured and organised following a rule in which adjacent data points, or nodes, sharing an edge cannot share the same colour.

"We colour a graph such that no two nodes that share an edge have the same color," said study first author Jason Ott from UC Riverside.

"The idea comes from maps. In a map of the US, for example, no two adjacent states share a color, which makes them easy to tell apart," explained co-author William Grover.

From EPA's database of chemicals categorised into their reactivity groups, ChemStor builds a chemical interaction graph, and computes the smallest number of colours that will shade the graph such that no two chemicals that can interact also share the same colour, the researchers said.

The software then assigns all the chemicals of each colour to a storage or waste container after confirming there is enough space, they added.

According to the study, chemicals with the same colour can be stored together without a dangerous reaction, while chemicals with different colours cannot.

If two or more chemicals can be combined in the same cabinet, or added to a waste container without forming dangerous combinations of chemicals, the software application determines that the configuration is safe.

The app also indicates if no safe storage or disposal configuration can be found for a chemical.

"I'm responsible for the safety of the people in my lab, and ChemStor would be like a safety net under our already strict storage protocols," Grover said.

The researchers, however, noted that the functionality of the app is currently limited to a command line interface, where the user manually enters the type of chemicals and amount of storage space into a computer.

They plan to make ChemStor more user-friendly by including a smartphone app which can use the camera to gather information about chemicals and storage options, as well as an integration with digital voice assistants.