Risk assessment of Naproxen and Sulfamethoxazole in Aquatic Ecosystem

Abstract

The development of science and technology has greatly contributed to the extension of human lifespan, resulting in an increase in the number of chronic diseases due to the aging of the population. For that reason, due to the development of new drugs and the use of life-prolonging treatments, the amounts of domestic pharmaceuticals used has increased rapidly, and the amount used to improve the productivity of agricultural and marine products and livestock is also showing a steady increase. In line with this trend, discharge standards for water pollutants have been steadily tightened, but water quality standards for pharmaceutical substances that may be contained in effluent have not yet been clearly established. In this research, we carried out the ecological impact stage test at “Pseudokirchneriella subcapitata”, “Daphina magna” and “Danio rerio’s embryo” for investigated the hazard identification of Naproxen and Sulfamethoxazole on aquatic organisms which is according to the OECD test guidelines. In consequence, we find the E(L)C50 of Naproxen and Sulfamethoxazole are 22.89 mg/l, 100.12 mg/l, 6.63 mg/l, and 0.69 mg/l, 104.21 mg/l, 22.32 mg/l. By these stats, we figure out PNEC of Naproxen and Sulfamethoxazole as 0.0663 mg/l and 0.0069 mg/l. With these results, 0.528 μg/l and 2.017 μg/l is maximum detectable amount about Naproxen and Sulfamethoxazole in government’s research for Young-San rivers in Korea, we figure out hazard quotient about Naproxen and Sulfamethoxazole as 0.0080 and 0.2923. It shows that Naproxen and Sulfamethoxazole has low hazard probability to currently water system in Korea. However, at present, both pharmaceutical substances are managed based on extremely low chronic toxicity values overseas and due to the characteristics of pharmaceutical substances, the amount used is steadily increasing, and it is very difficult to identify the discharge route and prevent discharge into the water system. Also, since various types of harmful substances exist in a mixture in water systems, continuous and regular monitoring is considered necessary, taking into consideration the mixed values of the hazard index for each substance.