The use of disinfectants is intensive and widespread during the pandemic. Disinfectants are mixed with various organic wastewater substances, and also resuspend from the soil surface during the rainy season, which are eventually discharged into river waters. This study aimed to assess the potential of alcohol in detoxifying wastes containing organic substances so as to secure their disposal into water bodies. Preparation of organic substance solutions, aquatic test biota, and measurement of substance concentration parameters, as well as substance toxicity to biota, were all carried out using international standard laboratory protocols. In addition, real wastewater containing various organic substances was also investigated. It was revealed that the toxicity rating of organic substances to microbes was in line with their toxicity rating to zebrafish aquatic biota indicator. The toxicity rating of organic substances to microbes was expressed in the ratio of biological to chemical oxygen demand. The acute lethal concentration of half the number of zebrafish was a rating of the toxicity of organic substances to aquatic biota. Both of these toxicity measures were closely related to the solubility properties of substances in organic matter, which were expressed as octanol-water partition coefficient values. A very important finding was the potential of alcohol to detoxify wastewater containing mixed organic substances to secure its discharge into water bodies. This supports the continued use of alcohol disinfectants as a health protocol in daily life.