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

Abstract

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 microg/L and approximately 1 microg/L, respectively. DSBP and DAS1 were widely distributed in Tokyo Bay waters at concentrations in the range of 0.019-0.264 microg/L and 0.021-0.127 microg/L, respectively. Comparison of these concentrations with those in sewage effluents (DSBP: 8 microg/L and DAS1: 2.5 microg/L on average) yielded sewage dilutions in Tokyo Bay on the order of 10(2). FWAs-salinity diagram in the Tamagawa Estuary showed fairly conservative behaviors of the FWAs with approximately 20% and approximately 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.

Recent Advances in the Use of Chemical Markers for Tracing Wastewater Contamination in Aquatic Environment: A Review

“…Dickerson et al [107] reported that detection of FWAs could be interfered by humics and dissolved carbons present in wastewater and surface waters by fluorometry. In addition, previous studies found FWAs could be photo-degraded in environment [60,63]. Another drawback of using FWAs as marker is the lack of correlation between FWAs and fecal bacteria [105].…”

“…Some fluorometers allow additional features of detecting FWAs in real time (continuous-flow reading). For instance, DAS 1 and DSBP have been successfully applied as chemical markers to detect wastewater contamination [60,61,63]. A study was performed on mountain river impacted by FWAs from both domestic and industrial sources [106].…”

Combining targeted sampling and fluorometry to identify human fecal contamination in a freshwater creek

“…Once in the wastewater, these compounds persist until they are exposed to sunlight, whereupon they photodegrade in a matter of hours (Kramer et al 1996). Below wastewater treatment plants, concentrations of optical brighteners average 0.5 mg L 21 in fresh waters (Poiger et al 1998) and a few mg L 21 in marine waters (Hayashi et al 2002).…”

Estimation of Transport and the Mass Balance of a Molecular Marker (DSBP) in Tokyo Bay Using an Ecological Model

“…결과적으로 높은 농도의 FWAs가 하수 배출수에 존재하게 되고, 일본 및 다른 여러 나라의 강물과 퇴적물에서 널리 검출된다 (Abe et al, 1983;Hayashi et al, 2002;Poiger et al, 1996;.…”

“…이러한 화학적 특성을 바탕으로 연안 환경에서 가정폐수에 의한 오염 연구에 대해 잠재적인 수용성 molecular markers로 제시되고 있다 (Stoll et al, 1997;Hayashi et al, 2002). Mills et al, 1985 ;(5) Hayashi et al, 2002 ;(6) (7) Kim et al, 2004b ;(8) Horiguchi et al, 2001 ; …”