Hematological profile as a crude oil exposure-related marker in wild rodents

The toxicity of petroleum components is well described in the literature, especially with regard to mutagenic and carcinogenic effects. In some groups of animals, such as birds, oil exposure seems to alter blood parameters, while this relationship is poorly understood in rodents. The study aimed to investigate alterations in hematological profile in the wild rodent Calomys laucha exposed to crude oil contaminated soils. In this study, males specimens of Calomys laucha were exposed for 14 days to two soils contaminated by petroleum: (I) landfarming soil, coming from a bioremediation area of contaminated soil from a Petrochemical Complex through landfarming technique and (II) soil of a simulated oil spill in laboratory conditions. The animals were exposed individually in cages containing 1 kg soil with free access to food and water. Control animals were exposed to an artificial uncontaminated soil. At the end of the experiment, animals were anesthetized and blood was collected for hematological profile. The animals exposed to soil landfarming had significant reduction in the number of bands, segmented, eosinophils, monocytes, lymphocytes and increased red cell distribution width (RDW), while animals exposed to simulated soil spillage in laboratory had decreased number of bands, but an increase in the number of lymphocytes and platelets. These changes in hemostasis may indicate an early stage of the development of associated pathologies, while the hematological profile can be used as a crude oil exposure-related marker in wild rodents.