Phytotoxicity Evaluation of Five Proton-Pump Inhibitors Through Plant-Based Eukaryotic Test Models

Proton-pump inhibitors (PPIs) are among the most commonly used over-the-counter drugs, although they have a number of adverse effects. Therefore, long-term use of PPIs may cause toxic effects on host cells and organs. This study evaluated the toxicity of five commonly used PPIs, namely esomeprazole (EPZ), lansoprazole (LPZ), omeprazole (OPZ), pantoprazole (PPZ), and rabeprazole sodium (RPZ-Na), on three plant-based eukaryotic test models (Allium cepa L., Allium sativum L., and Cicer arietinum L.). The PPIs were tested at 100 µg/mL on A. cepa and A. sativum at 24, 48, and 72 h, and on C. arietinum at 72 h of exposure time. Copper sulfate at 0.6 µg/mL was used as a positive control. Root growth profile was considered in the cases of A. cepa and A. sativum, while both shoot and root growth profiles were considered for C. arietinum. All the PPIs showed significant (p < 0.05) toxic effects as they reduced the number of roots and length of roots and shoots in the three test systems in comparison to the negative control group. PPZ exerted higher toxic effects on all the test systems than the other PPIs. All the PPIs exerted more toxic effects at 72 h than at 48 h of exposure time on A. cepa and A. sativum. In conclusion, PPIs exerted toxic effects on the root and/or shoot of A. cepa, A. sativum, and C. arietinum in a time-dependent manner. In this study, the results obtained with the A. sativum and C. arietinum tests were similar to those obtained with the A. cepa, suggesting that these less widely used tests may be useful as a complement to the traditional Allium test.