The ISO 10710 standard specifies a method for growth inhibition tests using macroalgae ** Ceramium tenuicorne ** in seawater and brackish water. This test is used to assess the inhibition of algae growth by potentially harmful substances in water quality, especially on marine and brackish water environments. Toxicity and ecological risks of contaminants in water can be effectively judged by observing the growth of fine algae under different concentrations of contaminants. The standard provides a scientific basis for environment protection and water quality monitoring, helping to assess the biological effects of water body pollution, especially on the health of algae communities in aquatic ecosystems.