Spatiotemporal variations of retinoic acids in the marine environment of Hong Kong

Abstract

As main metabolites of vitamin A, retinoic acids (RAs) are teratogens and critical for embryonic development of animals. Either deficiency or excessive intake of RAs can lead to abnormal development in animals. Teratogenic effects have been observed in amphibians, zebra fish embryos, Japanese flounder and mammals after exposure to elevated levels of RAs. Previous studies reported that RAs could be detected in sewage effluents and coastal seawaters while cyanobacteria could produce and release RAs. Therefore, this study investigated the spatiotemporal variation of concentrations of various RAs in seawater samples collected from 30 locations in the marine environment of Hong Kong, which is an urbanized coastal city and its coast suffers from eutrophication with frequent occurrence of harmful algal blooms. Our preliminary results suggested that concentrations of RAs and chlorophyll a varied spatially among different sampling locations