Petroleum hydrocarbon pollution in general, and benzene contamination of marine environments in particular, have had devastating effects on human health and bio-ecology. Furthermore, due to the insensitivity of conventional chemical methods in determining the early effects of harmful substance bioactivity at sublethal doses, there is a significant gap in the process of environmental protection and comprehensive planning in dangerous situations. This study systematically evaluates marine algae-based biomonitoring procedures for producing quantitative estimates of benzene-induced genotoxicity in coastal tropical seas and generating environmental health risk assessment models and early-warning systems. Four important macroalgae species ( Gracilaria verrucosa , Chaetomorpha crassa , Caulerpa racemosa var. corynephora, and Caulerpa lentillifera ) were tested as environmental health bio-sentinels under three environmentally relevant levels of benzene concentrations (83.10–983.49 µg/L) found in Asian coastal waters using exposure tests of 96 h. Alkaline comets were utilized as sensitive molecular sensors for assessing the genotoxic effects, resulting in hypersensitivity and species specificity. G. verrucosa was found to have the highest sensitivity (EC₅₀ = 83.7 µg/L). Probit regression modeling revealed strong dose–response associations (R 2 > 0.92), enabling the identification of no-effect and biomonitoring protection limits. The bioassay detected early genotoxic signals at concentrations below established aquatic life protection thresholds, reinforcing its value as a sensitive biomonitoring tool for coastal environments. Its 96-h turnaround time enhances operational efficiency for continuous environmental health surveillance, enabling early-warning detection, supporting regulatory compliance in coastal water-quality management, and contributing to global environmental quality standards and marine health security initiatives. Comprehensive overview of the marine algae-based biomonitoring protocol for benzene genotoxicity assessment. The workflow illustrates: (1) Selection of four tropical macroalgal species as bio-sentinels, (2) 96-h controlled exposure to environmentally relevant benzene concentrations, (3) DNA damage assessment using alkaline comet assay, (4) Species-specific dose–response relationships with G. verrucosa as the most sensitive indicator (EC₅₀ = 83.7 μg/L), and (5) Application in a four-tier environmental risk framework for coastal water-quality management. This protocol provides a cost-effective early-warning system for petroleum pollution monitoring in tropical marine ecosystems.
Chaikasem et al. (2026) studied this question.