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Sea-level rise (SLR) will cause coastal groundwater to rise in many coastal urban environments. Inundation of contaminated soils by groundwater rise (GWR) will alter the physical, biological, and geochemical conditions that influence the fate and transport of existing contaminants. These transformed products can be more toxic and/or more mobile under future conditions driven by SLR and GWR. We reviewed the vulnerability of contaminated sites to GWR in a US national database and in a case comparison with the San Francisco Bay region to estimate the risk of rising groundwater to human and ecosystem health. The results show that 326 sites in the US Superfund program may be vulnerable to changes in groundwater depth or flow direction as a result of SLR, representing 18.1 million hectares of contaminated land. In the San Francisco Bay Area, we found that GWR is predicted to impact twice as much land area as inundation from SLR, and 5,282 additional state-managed sites of contamination may be vulnerable to inundation from GWR in a 1.0 m SLR scenario. Increases of only a few centimeters of elevation can mobilize soil contaminants, alter flow directions in a heterogeneous urban environment with underground pipes and utility trenches, and result in new exposure pathways. Pumping for flood protection will elevate the saltwater interface, changing groundwater salinity and mobilizing metals in soil. Socially vulnerable communities are disproportionately exposed to this risk at both the national scale and in a regional comparison with the San Francisco Bay Area.

Introduction: Due to conduction disease and dyssynchrony in transthyretin amyloid cardiomyopathy (ATTR-CM), cardiac resynchronization therapy (CRT) may be beneficial. We aimed to determine the impact of CRT on clinical outcomes in ATTR-CM. Methods: We studied 116 consecutive ATTR-CM patients, 23 of whom underwent CRT (70% CRT + defibrillator, median 10 months (IQR 4-20) from ATTR-CM diagnosis). Outcome was a composite of 1 st cardiovascular hospitalization or all-cause mortality. CRT was treated as a time dependent co-variate and entered into multivariate Cox proportional hazards model. Results: Both groups were similar at diagnosis except for a higher proportion with atrial fibrillation (AF) and lower ejection fraction among those who underwent CRT ( Table 1) . CRT indication in 80% was progressive LV dysfunction with wide QRS [mean 152 ± 36 msec] and the remaining at time of AV node ablation for AF. Half of CRT group were ≥ NYHA class III at device implantation. Older age, higher National Amyloidosis Cohort (NAC) ATTR stage, and not taking tafamidis were significantly associated with the outcome. On multivariate analysis, CRT was associated with a HR of 0.6 (95% CI: 0.32 - 1.16) for all-cause mortality or cardiovascular hospitalization after adjusting for age at diagnosis, NAC ATTR stage, and tafamidis use ( Figure 1). Conclusion: CRT implantation maybe associated with improved outcomes in ATTR-CM. Larger prospective randomized, sham-controlled trials are warranted to confirm these findings.

Total oxidisable precursor assay (TOP assay) can degrade and convert “unknown” per- and polyfluoroalkyl substances (PFAS) to detectable PFAS. However, the detailed degradation pathway is still not known, particularly when the TOP assay is applied to analyse complex samples such as aqueous film-forming foam (AFFF). To gain insights into the pathway and the effectiveness of the TOP assay, several “known” compounds are first tested as controls, including sodium dodecyl benzene sulphate (SDBS), perfluorooctanoic acid (PFOA), perfluorooctanesulfonic acid (PFOS). Secondly, the test is expanded to several PFAS precursors such as 6:2 fluorotelomer sulfonate (6:2 FTS), 8:2 fluorotelomer sulfonate (8:2 FTS), and a cationic surfactant N-ethyl-N-(2-hydroxyethyl) perfluorooctyl sulfonamide (EtFOSE). Thirdly, the TOP assay is used to test “unknown” PFAS samples that have been previously used as AFFF in Australia. The degradation products are monitored, to compare the mass balance and propose the degradation pathway. While HPLC-MS/MS is typically employed to detect the individual TOP assay products, most of which are perfluoroalkyl carboxylic acids (PFCA), an app-based smartphone sensor can also provide semi-quantitative results as a sum. Overall, the results indicate the effectiveness of the TOP assay to assess the presence of PFAS precursors in the AFFF samples, with some variations in the end products. Recommendations for enhancement of the TOP assay are also provided.

Our ability to develop reliable, cost effective solutions for remediation and protection of water resources has matured in recent decades due to various factors, including advances in engineering techniques, improved monitoring capabilities, and access to numerous case studies, historical datasets, and research to aid in the selection and evaluation of mitigation/remediation approaches. Traditionally, historical baseline conditions, and reasonable projections of future conditions provide significant input into the decision-making process. The variability, and unpredictable nature of climate change now requires that the inherent uncertainty of future conditions (both short- and long-term) be incorporated in our remedial decision-making. From an engineering perspective, this may include more flexible (and likely more costly) remedial designs, or a shift from current preferences for longer-term passive approaches to consecutive, shorter-term active alternatives. Incorporating an economic decision-making tool provides a means to parametrize the uncertainties associated with climate change, and may identify “tipping points” where our decisions may change. Different communities, whose interpretations of and costs of resource protection may acutely reflect their own unique cultural values, incomes, or beliefs in the future, can evaluate feasible engineering/water resource protection strategies even in the absence of certainty about future climate conditions. The combined approach merges evaluation of traditional engineering/performance metrics with an economic model that we anticipate will improve the success of water management strategies.