The paper describes a methodology of determining toxicity sources, using bioassay based on wildlife objects that change their colorimetric parameters under the influence of toxic factors. The work explores the character of the dynamism of colorimetric attributes associated with plant pigments. It can be determined by computer processing of the data obtained from digital remote sensing of lands affected by toxic pollution by such relatively low-cost and straightforward methods as digital photography from an aircraft or a drone. The results obtained do not allow direct measurements but rather serve as a basis for the development and characterization of new biomarkers.