An indicator device, and a biological test method, for determining the toxic fingerprint and degree of toxicity, comprising at least 3, preferably at least 11, different microorganisms freeze-dried on an inert support material, wherein the microorganisms are being selected to form a high diversity of microorganisms, on the support material, with regards to the taxonomical tree and high diversity regarding responses to toxic chemicals. Further, a kit and a process for producing the indicator device is also disclosed.