Fluorescent Whitening Agents in Tokyo Bay and Adjacent Rivers:  Their Application as Anthropogenic Molecular Markers in Coastal Environments

• Published in: Environmental science & technology 2002-08, Vol.36 (16), p.3556-3563
• Main Authors: Hayashi, Yuko, Managaki, Satoshi, Takada, Hideshige
• Format: Article
• Language: English
• Subjects: Applied sciences; Biological and physicochemical phenomena; Biphenyl Compounds - analysis; Biphenyl Compounds - chemistry; Chemicals; Chromatography, High Pressure Liquid; Detergents - analysis; Detergents - chemistry; Earth sciences; Earth, ocean, space; Engineering and environment geology. Geothermics; Environmental Monitoring; Exact sciences and technology; Freshwater; Japan, Tamagawa R; Japan, Tokyo Bay; Natural water pollution; Organic chemistry; Photochemistry; Pollution; Pollution, environment geology; Sewage - chemistry; Stilbenes - analysis; Stilbenes - chemistry; Tokyo; Water Pollutants, Chemical - analysis; Water pollution; Water treatment and pollution; Waterways
• ISSN: 0013-936X; 1520-5851
• DOI: 10.1021/es011352o

Two kinds of stilbene-type fluorescent whitening agents (i.e., DSBP and DAS1), minor components of laundry detergents, were analyzed in surface waters of Tokyo Bay and adjacent rivers and in sewage effluents to examine their usefulness as molecular markers in the marine environment. Sensitive determination using HPLC (high performance liquid chromatography) with fluorescence detection with postcolumn UV radiator was employed. DSBP and DAS1 were found in Tokyo rivers at concentrations of a few μg/L and ∼1 μg/L, respectively. DSBP and DAS1 were widely distributed in Tokyo Bay waters at concentrations in the range of 0.019−0.264 μg/L and 0.021−0.127 μg/L, respectively. Comparison of these concentrations with those in sewage effluents (DSBP:  8 μg/L and DAS1:  2.5 μg/L on average) yielded sewage dilutions in Tokyo Bay on the order of 102. FWAs-salinity diagram in the Tamagawa Estuary showed fairly conservative behaviors of the FWAs with ∼20% and ∼10% removal of DSBP and DAS1, respectively. This is thought to be caused by photodegradation. The persistent nature of FWAs and their widespread distribution in coastal environments demonstrates the utility of FWAs in tracing the behavior of water from rivers and sewage outfalls. The DSBP/DAS1 ratio showed a decreasing trend from sewage effluents, to rivers, to Tokyo Bay, indicating selective photodegradation of DSBP. The DSBP/DAS1 ratio is proposed as an index of the degree of photodegradation and residence time and freshness of water mass in coastal environments.