the growth of local favelas, and unplanned urban development, generated pollution in the waters surrounding the island. starting in the 1970's, also due to waste from the greater rio de janeiro being discharged in the bay, the level of pollution in the area increased - making many of the beaches on the island unsuitable for swimming. The economic and urban expansion which brought jobs, prosperity and income to many of the citizens of the island, also resulted in unexpected levels of contamination.
