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1. Current and future approaches to wet weather flow management: A review

   https://doi.org/10.1002/wer.1506  

   Peters, Paige E. ; Zitomer, Daniel H. ( January 2021 , Water Environment Research)

   Sewers can become hydraulically overburdened during high‐intensity precipitation resulting in untreated water entering receiving streams. Combined (CSOs) and sanitary sewer overflows (SSOs) cause adverse public health and environmental impacts as well as management challenges for many wastewater utilities. This novel review presents information regarding wet weather flow regulation, impacts, and current management methods, and offers ideas for future approaches in the United States. Currently, storage followed by conventional municipal water reclamation facility treatment after precipitation events is often employed. Stand‐alone alternative technologies include high‐rate solids removal, rapid disinfection, filtration, and green infrastructure. However, most current stand‐alone approaches do not address soluble BOD₅or emerging contaminants in stormwater and wastewater. As the needs for wet weather flow management change, future approaches should include a goal of zero overflows and achieve effluent quality as good as or better than conventional treatment. To help achieve zero overflows and complete treatment, the “peaker facility” concept is proposed. The peaker facility often remains idle but treats excess flow when needed. Considering the challenges of remaining idle for long periods, starting up quickly, and handling high flows, chemical oxidation may be an applicable peaker facility component. However, more research and development are needed to determine best practices.

   Combined (CSO) and sanitary sewer overflows (SSOs) pose both environmental and public health risks as untreated water is discharged into lakes and rivers during high‐intensity rain events.

   Current stand‐alone approaches for managing or treating CSOs focus on particulate BOD/COD and solids removal, and do not typically address soluble BOD or emerging contaminants in stormwater and wastewater (including pathogens).

   New wet weather policies and regulations encourage more holistic approaches by wastewater utilities, and future approaches should include a zero‐overflow goal for all CSOs and SSOs.

   To help achieve zero overflows, the concept of the “peaker facility” is proposed.

   Chemical oxidation may be an applicable component of peaker facilities for its short detention time and ability to remove, oxidize, or inactive water impairment‐causing contaminants.

    

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2. Local and landscape characteristics shape amphibian communities across production landscapes in the Western Ghats

   https://doi.org/10.1002/2688-8319.12110  

   Sankararaman, Vishnupriya ; Dalvi, Shashank ; Miller, David A. W. ; Karanth, Krithi K. ( November 2021 , Ecological Solutions and Evidence)

   Global tropical forests have been modified and fragmented by commodity agroforests, leading to significant alterations in ecological communities. Nevertheless, these production landscapes offer secondary habitats that support and sustain local biodiversity. In this study, we assess community level and species‐specific responses of amphibians to land management in areca, coffee and rubber, three of the largest commodity agroforests in the Western Ghats.

   A total of 106 agroforests across a 30,000‐km²landscape were surveyed for amphibians using a combination of visual and auditory encounter surveys. We used a Bayesian multi‐species occupancy modelling framework to examine patterns of species richness, beta diversity, dominance structure and individual species occupancies. The influence of biogeographic variables such as elevation and latitude as well as microhabitat availability of streams, ponds and unpaved plantation roads was tested on amphibian species occupancy.

   Coffee agroforests had the highest species richness and lowest dominance when compared to areca and rubber. Beta diversity was highest in areca for within agroforest measures. Compared across agroforests, coffee had highest beta diversity with areca and rubber. Both elevation and latitude showed an overall positive association with amphibian occupancy, although species‐specific responses varied considerably.

   Microhabitat availability was one of the strongest predictors of amphibian occupancy, with mean community response being positive with presence of water bodies and roads. Pond presence increased species richness per site by 34.7% (species‐specific responses in occupancy ranged from –2.7% to 327%). Stream presence alone did not change species richness but species‐specific response ranged from –59% to 273%. Presence of plantation roads also increased species richness by 21.5% (species‐specific response ranged from –82% to 656%). Being unpaved with little vehicular traffic, plantation roads seem to provide additional habitats for amphibians. Presence of all three microhabitats at a site increased species richness by 75%.

   Our study highlights the importance of land management strategies that maintain diverse native canopy and freshwater bodies and other microhabitats in sustaining amphibian fauna. Market‐driven land‐use change from coffee to other agroforest types will have detrimental effects on amphibian communities and their long‐term sustainability in the Western Ghats.

    

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3. Protecting wastewater workers from disease risks: Personal protective equipment guidelines

   https://doi.org/10.1002/wer.1249  

   LeChevallier, Mark W. ; Mansfield, Theodore J. ; Gibson, Jacqueline MacDonald ( October 2019 , Water Environment Research)

   The 2013–2016 Ebola epidemic revived concerns about infection risks to wastewater workers. Prior research has shown that wastewater can contain a variety of known and emerging pathogens and that wastewater workers are at increased risk of infectious illnesses. However, guidelines on using personal protective equipment (PPE) to decrease these risks are lacking. We engaged 34 wastewater utility personnel and public health experts to conduct a job safety analysis identifying tasks in which workers could be exposed to pathogens and to develop a PPE selection matrix for preventing those exposures. We identified 43 relevant job tasks. Recommended PPE ranges from durable gloves (all tasks) to safety glasses (24 tasks), Tyvek suits or coveralls (4 tasks), and respiratory protection (N95 mask or face mask, depending on the activity, 10 tasks). The PPE selection matrix can serve as a guide for protecting the 120,000 wastewater workers in the United States from known and emerging pathogens.

   Wastewater workers are at increased risk of infectious illnesses.

   Policies to protect wastewater workers from these illnesses are lacking.

   We developed guidelines for use of personal protective equipment by wastewater workers to prevent exposure to infectious agents.

    

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4. Scientific shortcomings in environmental impact statements internationally

   https://doi.org/10.1002/pan3.10081  

   Singh, Gerald G. ; Lerner, Jackie ; Mach, Megan ; Murray, Cathryn Clarke ; Ranieri, Bernardo ; St‐Laurent, Guillaume Peterson ; Wong, Janson ; Guimaraes, Alice ; Yunda‐Guarin, Gustavo ; Satterfield, Terre ; et al ( March 2020 , People and Nature)

   Governments around the world rely on environmental impact assessment (EIA) to understand the environmental risks of proposed developments.

   To examine the basis for these appraisals, we examine the output of EIA processes in jurisdictions within seven countries, focusing on scope (spatial and temporal), mitigation actions and whether impacts were identified as ‘significant’.

   We find that the number of impacts characterized as significant is generally low. While this finding may indicate that EIA is successful at promoting environmentally sustainable development, it may also indicate that the methods used to assess impact are biased against findings of significance. To explore the methods used, we investigate the EIA process leading to significance determination.

   We find that EIA reports could be more transparent with regard to the spatial scale they use to assess impacts to wildlife. We also find that few reports on mining projects consider temporal scales that are precautionary with regard to the effects of mines on water resources. Across our sample of reports, we find that few EIAs meaningfully consider the different ways that cumulative impacts can interact.

   Across countries, we find that proposed mitigation measures are often characterized as effective without transparent justification, and sometimes are described in ways that render the mitigation measure proposal ambiguous.

   Across the reports in our sample, professional judgement is overwhelmingly the determinant of impact significance, with little transparency around the reasoning process involved or input by stakeholders.

   We argue that the credibility and accuracy of the EIA process could be improved by adopting more rigorous assessment methodologies and empowering regulators to enforce their use.

   A freePlain Language Summarycan be found within the Supporting Information of this article.

    

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5. A chloride channel blocker prevents the suppression by inorganic phosphate of the cytosolic calcium signals that control muscle contraction

   https://doi.org/10.1113/JP279917  

   Ferreira, Juan J. ; Pequera, Germán ; Launikonis, Bradley S. ; Ríos, Eduardo ; Brum, Gustavo ( October 2020 , The Journal of Physiology)

    Accumulation of inorganic phosphate (P_i) may contribute to muscle fatigue by precipitating calcium salts inside the sarcoplasmic reticulum (SR). Neither direct demonstration of this process nor definition of the entry pathway of P_iinto SR are fully established.

    We showed that P_ipromoted Ca²⁺release at concentrations below 10 mmand decreased it at higher concentrations. This decrease correlated well with that of [Ca²⁺]_SR.

    Pre‐treatment of permeabilized myofibres with 2 mmCl⁻channel blocker 9‐anthracenecarboxylic acid (9AC) inhibited both effects of P_i.

    The biphasic dependence of Ca²⁺release on [P_i] is explained by a direct effect of P_iacting on the SR Ca²⁺release channel, combined with the intra‐SR precipitation of Ca²⁺salts. The effects of 9AC demonstrate that P_ienters the SR via a Cl⁻pathway of an as‐yet‐undefined molecular nature.

   Fatiguing exercise causes hydrolysis of phosphocreatine, increasing the intracellular concentration of inorganic phosphate (P_i). P_idiffuses into the sarcoplasmic reticulum (SR) where it is believed to form insoluble Ca²⁺salts, thus contributing to the impairment of Ca²⁺release. Information on the P_ientrance pathway is still lacking. In amphibian muscles endowed with isoform 3 of the RyR channel, Ca²⁺spark frequency is correlated with the Ca²⁺load of the SR and can be used to monitor this variable. We studied the effects of P_ion Ca²⁺sparks in permeabilized fibres of the frog. Relative event frequency (f/f_ref) rose with increasing [P_i], reaching 2.54 ± 1.6 at 5 mm,and then decreased monotonically, reaching 0.09 ± 0.03 at [P_i] = 80 mm. Measurement of [Ca²⁺]_SRconfirmed a decrease correlated with spark frequency at high [P_i]. A large [Ca²⁺]_SRsurge was observed upon P_iremoval. Anion channels are a putative path for P_iinto the SR. We tested the effect of the chloride channel blocker 9‐anthracenecarboxylic acid (9AC) on P_ientrance. 9AC (400 µm)applied to the cytoplasm produced a non‐significant increase in spark frequency and reduced the P_ieffects on this parameter. Fibre treatment with 2 mm9AC in the presence of high cytoplasmic Mg²⁺suppressed the effects of P_ion [Ca²⁺]_SRand spark frequency up to 55 mm[P_i]. These results suggest that chloride channels (or transporters) provide the main pathway of inorganic phosphate into the SR and confirm that P_iimpairs Ca²⁺release by accumulating and precipitating with Ca²⁺inside the SR, thus contributing to myogenic fatigue.

    

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