Surfactants in sediment of Itanhaém Estuary, São Paulo, Brazil

This study investigated surfactant levels in the sediment of Itanhaém Estuary through colorimetric methods with methylene blue active substances (MBAS). Samples were collected with a Van Veen bottom sampler at eight sampling points during autumn, winter, and spring of 2015. The results demonstrate growing detergent deposition in the sediment of the estuary. Surfactant concentration was higher (16.18 μg MBAS g−1) around the sewage treatment plant (STP) than in the estuary in autumn, after the vacation/summer season when the population of the city had increased due to tourism. There was a significant (p