Ion-exchange chromatography in the assessment of environmental pollution with chlortetracycline

Chemical substances such as drugs pose a threat to the environment. One of the substances recorded in soil and water is chlortetracycline, an antibiotic used in veterinary medicine. Plants exposed to such xenobiotics show changes in the content of biogenic amines. An analytical technique - ion exchange chromatography is used to assess their content. The occurrence of these active compounds is used to determine the degree of environmental pollution with chemical substances. The study aimed to evaluate the toxicity of chlortetracycline (CTC) at concentrations of 0; 0.05; 0.1; 0.2 0.5;1; 2; 3; and 5 mM towards the test organism Lemna minor, and determine the content of biogenic amines in the plant tissues. The content of biogenic amines was analyzed by ion-exchange chromatography with post-column ninhydrin derivatization and photometric detection. The Lemna test proved that increasing concentrations of CTC had a toxic effect on the plants. It was calculated that the Lowest Observed Effects Concentration (LOEC) of CTC at >0.04 mM and >0.05 mM was phytotoxic to L. minor growth and yield. It was determined that the levels of histamine, tyramine, and cadaverine exhibited an increase, reaching 1.04, 1.90, and 3.10 µg g^-1 of tissue at 2.00 mM CTC. Simultaneously, spermine and putrescine increased to 1.21 and 3.89 µg g^-1 of tissue at concentrations of 0.10 and 0.50 mM of the drug. Conversely, the study revealed an over 88 % reduction in spermidine in plants at 5 mM of CTC. Using ion-exchange chromatography, analysis of biogenic amines, particularly spermidine and cadaverine, highlighted these intra-tissue compounds as sensitive biomarkers for water contamination with the tested drug. This research confirmed that the Lemna test is effective for assessing CTC toxicity and that ion-exchange chromatography is useful for evaluating environmental pollution by this antibiotic.