Dietary exposure of adult male F344 rats to 0, 320, 1250, 5000, or 20,000 ppm DEHP for 60 consecutive days resulted in a dose-dependent reduction in total body, testis, epididymis, and prostate weights at 5000 and 20,000 ppm. Degenerative changes were observed in testis, along with decreased testicular zinc content, reduced epididymal sperm density and motility, and increased occurrence of abnormal sperm at 20,000 ppm. There was a trend towards reduced testosterone and increased luteinizing hormone and follicle stimulating hormone in serum at 5000 and 20,000 ppm. The mean percentage of fertile animals was unchanged and reduction in fertility parameters, although not marked in severity, were correlated with gonadal effects. Average litter size was reduced at 20,000 ppm, but initial pup weights and growth were unaffected. There were no grossly observed abnormalities in the offspring and the rate of neonatal deaths was similar in control and DEHP treated groups. Characteristic toxicity manifestations of DEHP included dose-dependent enlargement of liver and reduced sperm triglycerides and cholesterol. Additionally, serum albumin and total proteins were dose dependently increased upon treatment with DEHP. Cessation of exposure to DEHP initiated partial to complete recovery from toxicity in most cases. The magnitude of recovery were variable with that of the gonads being slower than other systems. These data suggest a lack of reproductive dysfunction in F344 male rats at DEHP doses below 20,000 ppm which produced measurable testicular degeneration and afflicted epididymal sperm morphology under the present experimental conditions.

A recent article in PNAS contained shocking assertions that carbon emissions "already have exceeded the critical level" for New Orleans (1). In this letter, we challenge how the analysis was applied to New Orleans and point out that this latest in a series of "New Orleans is doomed" reports actually undermines very important, on-the-ground efforts to enhance the city's resilience to climate change and sea level rise.As an implicit assumption, the study's approach applies a uniform and spatially homogeneous rate of inundation for a given level of sea level rise. This "bathtub" model of inundation due to sea level rise ignores hydrological barriers, such as the levees and flood walls, and actually predicts that most of our city is presently part of the ocean. Simply put, the current existence of our city on dry land demonstrates that the model is poorly calibrated.However, levees and flood walls are only part of our city's resilience strategy. Restoring our natural coastal lines of defense-marsh, barrier islands, and natural ridges-is an important part of our strategy to combat sea level rise. Along with levees, these natural landscape features are all elements in our state's coastal master plan.We agree that now is the time to act on carbon emissions. In fact, our adaptations to sea level rise, which span many decades now, explain why land loss in Louisiana has reversed in recent years (2) and why we have been able to rebuild thousands of acres of coastal marsh, which happen to be efficient carbon sinks, to protect our levees and our communities (3). However, there is no guarantee of success. The authors are correct to point out that urgent action is required (1). This urgency is why we continuously advocate for a federal commitment to our master plan and coastal restoration efforts.Failing to disclose adequately the assumptions of the bathtub model creates the risk that Americans will erroneously conclude that New Orleans' fate is sealed. It hinders support crucial to the success of our master plan. Why should taxpayers invest in a city where the "critical level" has already locked in its fate? The false narrative presented by this study, based on a poorly calibrated model, discourages efforts to implement the very policies that could make our region sustainable.The bathtub model of coastal inundation (4) is simple and easy to use. However, its simplicity masks many important local factors, such as levees and coastal restoration. If the analysis is not going to account for these factors, then the results should exclude areas where these factors are dominant. This practice is common in storm surge modeling (5), which is effectively a more rapid and higher type of sea level rise.With climate change science facing so many questions regarding its credibility, we advise that future sea level studies also account for important local factors that violate the assumption of the bathtub model, or at least explicitly state this assumption along with its limitations in cities such as New Orleans.

Wetland loss is increasing rapidly, and there are gaps in public awareness of the problem. By crowdsourcing image analysis of wetland morphology, academic and government studies could be supplemented and accelerated while engaging and educating the public. The Land Loss Lookout (LLL) project crowdsourced mapping of wetland morphology associated with wetland loss and restoration. We demonstrate that volunteers can be trained relatively easily online to identify characteristic wetland morphologies, or patterns present on the landscape that suggest a specific geomorphological process. Results from a case study in coastal Louisiana revealed strong agreement among nonexpert and expert assessments who agreed on classifications at least 83% and at most 94% of the time. Participants self-reported increased knowledge of wetland loss after participating in the project. Crowd-identified morphologies are consistent with expectations, although more work is needed to directly compare LLL results with previous studies. This work provides a foundation for using crowd-based wetland loss analysis to increase public awareness of the issue, and to contribute to land surveys or train machine learning algorithms.

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