Sewage contamination assessment in an urbanized tropical estuary in Northeast Brazil using elemental, isotopic and molecular proxies

A novel in situ method for linear alkylbenzene sulfonate quantification in environmental samples using a digital image-based method

“…The distribution of LABs (also associated with sewage effluents) in sediments from the CES was also related to the proximity of sewage release/disposal in an area of low hydrodynamic activity. 42 The sample collected at St #4 (salinity 36), in front of the Port of Recife (Fig. 1), exhibited the highest LAS concentration, probably reecting washing water from ship tanks.…”

“…In this sense, the present study sought to use the DIB/smartphone method for the analysis and determination of LAS in the Capibaribe River Estuarine System (CES), which has suffered from this type of pollution recently. 42 The CES is located on the coast of the Brazilian Northeast region. The estuarine system straddles the Recife metropolitan region, which has a total population of 3.7 million people, 46 with less than 50% of houses connected to sanitation systems.…”

“…47 The CES was chosen for to conduct the present study because it has been suffering from pollution over the course of decades, 41,48 with greater impact observed downstream, as it approaches the mouth of the Atlantic Ocean; the system has also been suffering from widespread irregular disposal of domestic sewagethe result of growing, irregular urbanization, where the lack of sewage treatment has become one of the major causes of the environmental problems observed in the region. 41,42,48 Based on the studies conducted on the CES, this vital estuarine system has been found to be contaminated by toxic metals, 49 petroleum hydrocarbons, 50,51 organochlorines, 52 organotin, 53 and linear alkylbenzenes (LABs), 42 which are precursor compounds of LAS; all these studies have pointed out domestic effluents as a signicant source of these contaminants. Although the Pernambuco Environmental Pollution Control and Water Resources Management Company classies the Capibaribe River estuary as highly polluted, 54 the ecosystem Paper Analytical Methods services provided by the estuary system, including food and economic resources, are deemed essential for the mainstay and survival of the local communities.…”

“…40 The DIB method can be applied for the analysis of a wide range of samples of water bodies, including rivers, lakes, estuaries, and oceans, where field studies can be carried out to identify the impact of urban pollution. 41,42 This is possible because its practical and portable nature allows it to be adapted and used in different research contexts, covering various areas of study related to the analysis and monitoring of water quality.…”

“…47 The CES was chosen for to conduct the present study because it has been suffering from pollution over the course of decades, 41,48 with greater impact observed downstream, as it approaches the mouth of the Atlantic Ocean; the system has also been suffering from widespread irregular disposal of domestic sewage – the result of growing, irregular urbanization, where the lack of sewage treatment has become one of the major causes of the environmental problems observed in the region. 41,42,48…”