Water Pollution by Surfactants: Fluctuations Due to Tourism Exploitation in a Lagoon Ecosystem

Abstract

This paper describes recent levels of surfactants measured in a coastal lagoon ecosystem highly stressed by human activites: the Orbetello lagoon (Southern Tuscany, Italy, Ramsar Site IT008). Significance of difference among concentrations measured before and after summertime are explored in order to evaluate effects related to tourism exploitation. Among surfactants, methylene blue active anionic substances (MBAS) are selected as tracers for untreated discharges originated by domestic and urban activities. Water samplings were performed in 2011 following a randomly replicated nested logic model (n = 144). MBAS mean level of 0.070 mg.L^–1 (<0.001 - 0.259 mg.L^–1) and 0.530 mg.L^–1 (<LOQ-1.866 mg.L^–1) are respectively recorded in June and October evidencing a significant increase after the touristic season. Possible MBAS concentration phenomena could be induced by different evaportaton rates among sampling stations and between winter and summer seasons and were evaluated, in this study, using water salinity as possible factor affecting samples segregations. Results evidence that differences of MBAS levels related to evaporation rates are trascurabile if compared to the variability induced by the presence of not-collected wastewater hot-spot pollution sources located closed around the urban settlement and along sandbars. Measured levels of surfactants could act negatively on living organisms both animals and plants contributing to affect Orbetello lagoon biodiversity. In this ecosystem, after the complete reorganization of urban wastewater treatment plants occured in 2008, further management actions should be focalized on reducing untreated sources of MBAS

Aşağı Melet Irmağı (Ordu, Türkiye) Su Kalitesi ve Kirlilik Düzeyinin Araştırılması

“…Anionic surfactant concentration in water was above the permissible level of 0.2 mgL -1 according to Anonymous (2004). Our results (0.97 mgL -1 ) are far higher than the data obtained by similar studies in other countries where sewage treatment systems have been established such as Orbetello Lagoon (0.070 mgL -1 ), Southern Tuscany, Italy (Renzi et al 2012). …”

Responses of Aquatic Vegetation to Pollution: Preliminary Results on Ecotoxicological Effects and Bioenrichment Factors

“…Mercury concentrations ranged within values measured in highly polluted sites within the Orbetello lagoon. Concerning surfactants, exposure concentrations selected in this paper are respectively lower and higher than average levels measured in water of the Orbetello lagoon [18]. Prior to exposure, the tissue integrity of collected species was verified by means of light microscopy.…”

“…Four different aquatic vegetation species (C. linum, V. aegagrophyla, G. longissima, R. cirrhosa) were collected in the Orbetello lagoon in spring 2013. The Orbetello lagoon was selected due to our extensive knowledge on macroalgae and phanerogam distribution and fluctuations within this ecosystem, and the documented geo-referenced position of local human-generated pollution sources [11] [18], which made it possible to avoid the most heavily polluted sites. Before the experiments, sampled species were stored in natural marine water collected from a local unpolluted site (Due Pini, Argentario Mountain), physical-chemical water descriptors from which were also monitored ( Table 1).…”

“…Previous research has evidenced that some of these chemicals could severely interfere with unicellular aquatic vegetation, producing significant alterations in cellular metabolic pathways, cellular biovolumes and bioluminescence [11]. Furthermore, surfactants [18] and trace elements are highly concentrated in transitional water ecosystems [19] [20], as both accumulate in sediments [21]. Sediment re-suspension occurring during dredging operations (i.e.…”

Untitled

“…High AS concentration possibly caused by this Bosphorous outflow which is mixing with cold intermediate layer (water temperature decreases to 7°C) on the continental shelf just north of the Bosphorus (Tolmazin, 1985bin Murray et al, 2005. Other reasons for Şile station possibly related to summer tourism (Renzi et al, 2012;Okbah et al, 2013) and deep-sea discharge system. Because, Şile is a small resort town and the amount of waste water increases with increasing population density about four-five times during summer (SDG, 2008) and municipal wastewater is dumped to seawater via deep-sea drainage system.…”