Detecting device for detecting contaminant and/or composition chemical agents in a real matrix, particularly in an environmental liquid, in a food or in a biologic fluid, said device comprising: - a housing - at least one material (MS1, MS2) responsive to at least one contaminant and/or composition chemical agent present in said real matrix, - supporting means for supporting said at least one material (MS1, MS2), - a detection unit for detecting said contaminant and/or composition chemical agent through changes in optical and/or electrical properties of said material (MS1, MS2), and further comprising for each material (MS1, MS2) responsive to at least one contaminant and/or composition chemical agent: - at least a light source or emitter capable of emitting one or more luminous radiation on said responsive material (MS1, MS2), said light source being connected to said detection unit, - an optical receiver for receiving the light radiation reflected from said material (MS1, MS2) and/or emitted by it, said optical receiver being connected to said detection unit and transmitting to it one or more signals containing information on the optical properties of said material (MS1, MS2), and - a pair of electrodes (6, 7; 6', 7'), each of which has one end in contact with said material (MS1, MS2), and the other end electrically connected to said detection unit, said detection unit being capable of applying, through said electrodes, a potential difference on said responsive material (MS1, MS2) so that the latter generates one or more response signals containing information on its electrical properties, said device further comprising that said light source is capable of emitting said luminous radiations in sequence and each luminous radiation has a respective predetermined wavelength; and in that said detection unit comprises a database, within which are stored: - a plurality of predetermined responsive materials; - a plurality of optical spectra associated with each one of said predetermined responsive materials, obtained in the absence and in the presence of a predetermined potential difference applied to each one of them, each optical spectrum being associated with the interaction with one or more predetermined contaminant and/or composition chemical agents, - a plurality of changes of electrical properties associated with each one of said predetermined responsive materials, each change of electrical property being associated with the interaction with one or more predetermined contaminant and/or composition chemical agents, wherein said detection unit is configured to receive signals containing information about optical properties of said responsive material (MS1, MS2), and/or signals containing information about electrical properties of the same responsive material, to obtain optical spectra of each responsive material (MS1, MS2), in presence or absence of a potential difference applied by said detection unit, starting from luminous radiations received from said optical receiver, and to carry out a first comparison between each optical spectrum of said contaminant and/or composition chemical agent to be detected and the respective optical spectrum stored within said database, and/or to carry out a second comparison between changes of electrical properties of each responsive material (MS1, MS2) and changes of electrical properties of each responsive material (MS1, MS2) stored within said database, so that from one of said comparisons or from combination of said comparisons one or more contaminant and/or composition chemical agents in said real matrix is/are identified. - a housing - at least one material (MS1, MS2) responsive to at least one contaminant and/or composition chemical agent present in said real matrix, - supporting means for supporting said at least one material (MS1, MS2), - a detection unit for detecting said contaminant and/or composition chemical agent through changes in optical and/or electrical properties of said material (MS1, MS2), - at least a light source or emitter capable of emitting one or more luminous radiation on said responsive material (MS1, MS2), said light source being connected to said detection unit, - an optical receiver for receiving the light radiation reflected from said material (MS1, MS2) and/or emitted by it, said optical receiver being connected to said detection unit and transmitting to it one or more signals containing information on the optical properties of said material (MS1, MS2), and - a pair of electrodes (6, 7; 6', 7'), each of which has one end in contact with said material (MS1, MS2), and the other end electrically connected to said detection unit, said detection unit being capable of applying, - a plurality of predetermined responsive materials; - a plurality of optical spectra associated with each one of said predetermined responsive materials, obtained in the absence and in the presence of a predetermined potential difference applied to each one of them, each optical spectrum being associated with the interaction with one or more predetermined contaminant and/or composition chemical agents, - a plurality of changes of electrical properties associated with each one of said predetermined responsive materials, each change of electrical property being associated with the interaction with one or more predetermined contaminant and/or composition chemical agents,