Carnival Corp. has withheld water pollution data from Alaska regulators for months, raising concerns about the lack of transparency surrounding the use of open-loop scrubbers, which have been criticized for reducing air pollution by converting it into water pollution. The company, which owns five cruise lines in state waters, has been accused of failing to provide data about a major source of water pollution for months. Annie Goodenough, a state inspector, found sooty, black globs coming from the scrubber discharge point of the Discovery Princess, which exceeded federal limits on both Sept. 2 and 3 during the same period as Goodenough was on board. The incident highlights tensions between Carnival and the state over the proliferation of these scrubbers globally, which use seawater to remove contaminants from ship exhaust before diluting them and release the resulting wash water into the ocean. The scrubber process can be toxic for marine life and can lead to environmental degradation.