Wastewater from food processing industries contains synthetic dyes and preservatives that may pose phytotoxic and genotoxic risks. The present work represents an exploratory study based on a wastewater source and sampling period. Wastewater was characterized by physicochemical analysis and high-performance liquid chromatography (HPLC). Onion seeds and bulbs were exposed to 0% (control), 20%, 40%, 60%, 80%, and 100% wastewater dilution. DNA was extracted from root cells using the cetyltrimethylammonium bromide (CTAB) method. The DNA damage was analyzed by the comet assay. HPLC analysis confirmed the presence of sorbic acid, citric acid, benzoic acid, butylated hydroxyanisole (BHA), and butylated Hydroxytoluene (BHT) by showing corresponding peaks. The mean root length in wastewater was significantly reduced by 55%, 50%, and 65% on days 3, 5, and 7, respectively, relative to the control. On day 3, the highest genotoxicity at 100% wastewater was indicated by 96.69% tail DNA, a tail moment of 108.3 a.u., an Olive tail moment of 58.01 a.u., and a comet length of 136 µm. Enhanced DNA damage persisted on days 5 and 7, with comet lengths reaching 127–149 µm and 111–182 µm, respectively. Although the observed effects may reflect general cytotoxicity arising from a complex wastewater mixture and showed that untreated food processing wastewater presents a significant genotoxic risk and requires effective treatment prior to reuse.

Certain synthetic food additives have been found to induce DNA damage in plant cells, primarily in the form of mutations and chromosomal abnormalities. This research aimed to assess the genotoxic potential of two commonly used food colors (Allura red and tartrazine) and two preservatives (boric acid and sodium benzoate) on the root cells of garlic (Allium sativum L.). Garlic roots were treated with various concentrations of food colors (0.1, 01, and 10 g/L) and food preservatives (1, 2, and 4 g/L) for 24 h. Root tip cells were observed under the microscope to check chromosomal abnormalities. The mitotic index observed a maximum of 11.32% at a 10 g/L concentration of Allura red and 19.88% for tartrazine at a 10 g/L concentration. The mitotic index for boric acid and sodium benzoate was maximum (9.80 and 10.95%, respectively) at a concentration of 4 g/L each. An abnormality index was recorded for Allura red (3.01%) and (2.98%) for tartrazine at a 10 g/L concentration. The abnormality index for boric acid was highest (5.88%) at a concentration of 4 g/L. The abnormality index for sodium benzoate was maximum at 5.17% at 4 g/L. Overall, genotoxicity increased with the increasing concentration of food additives.