Helena Solo-gabriele - Academia.edu (original) (raw)

Papers by Helena Solo-gabriele

Humans may be exposed to microbial pathogens at recreational beaches via environmental sources, s... more Humans may be exposed to microbial pathogens at recreational beaches via environmental sources, such as water, sand, and aerosols. Although infectious disease risk from exposure to waterborne pathogens has been an active area of research for decades, sand is a relatively unexplored reservoir of pathogens and fecal indicator bacteria (FIB). Beach sand and water habitats provide unique advantages and challenges to pathogen introduction, growth, and persistence, as well as continuous exchange between habitats. Models of FIB and pathogen fate and transport in sandy beach habitats can help predict the risk of infectious disease from recreational water use, but filling knowledge gaps such as decay rates and potential for microbial growth in beach habitats is necessary for accurate modeling. Climatic variability, whether natural or anthropogenically-induced, adds complexity to predictive modeling, but may increase human exposure to waterborne pathogens via extreme weather events, warming o...

Marine Pollution Bulletin, 2019

The objective of this study was to evaluate relationships between local factors (beach geomorphol... more The objective of this study was to evaluate relationships between local factors (beach geomorphology and management) and regional factors (infrastructure improvements and temperature changes) against levels of fecal indicator bacteria (FIB) at recreational beaches. Data were evaluated for 17 beaches located in Monroe County, Florida (Florida Keys), USA, including an assessment of sanitary infrastructure improvements using equivalent dwelling unit (EDU) connections. Results show that elevated FIB levels were associated with beach geomorphologies characterized by impeded flow and by beaches with lax management policies. The decrease in EDUs not connected coincided with a decrease in the fraction of days when bacteria levels were out of compliance. Multivariate factor analysis also identified beach management practices (presence of homeless and concession stands) as being associated with elevated FIB. Overall, results suggest that communities can utilize beach management strategies and infrastructure improvements to overcome the negative water quality impacts anticipated with climate change.

FEMS Microbiology Ecology

The water surface microlayer (SML) serves as a boundary through which microbes can be exchanged. ... more The water surface microlayer (SML) serves as a boundary through which microbes can be exchanged. To evaluate exchanges of microbes, this study compared microbial communities within different reservoirs, with an emphasis on the water SML and aerosols. Additionally, the microbial communities during a sewage spill and perigean tides were evaluated and the results were compared to times without these events. Results show that during perigean tides and during the sewage spill, levels of culturable bacteria were highest and showed an increase via sequencing in potential pathogenic bacteria (Corynebacterium and Vibrio, which increased from 3.5%-1800% depending on sample type). In the aerosol samples, Corynebacterium (average of 2.0%), Vibrio (1.6%), and Staphylococcus (10%), were the most abundant genera. Aerosolization factors, which were used to examine the transfer of the microbes, were high for these three genera. Measurements of general marine bacteria (GMB) by culture showed a weak b...

American Scientific Research Journal for Engineering, Technology, and Sciences, 2015

Chromated copper arsenate (CCA) was the dominant wood preservative used for outdoor wood products... more Chromated copper arsenate (CCA) was the dominant wood preservative used for outdoor wood products to prevent structural decay prior to its phase down starting from 2004. Incineration is one key disposal alternative for CCA-treated wood; however, it results in volatilization of metals at high temperature and accumulation of metals in ash. The objective of this study was to assess alkaline earth and iron based sorbents for their capability to minimize leaching of metals from the incinerator ash. Experiments were carried out by heating CCA metal spikes combined with sorbents to temperatures of 700, 900 and 1100 o C. The residual ash was analyzed for leaching retention using the toxicity characteristic leaching procedure (TCLP) and speciation by X-ray diffraction (XRD). Results show that alkaline earth sorbents (cement, calcium hydroxide and magnesium hydroxide) were the most promising for reducing the leaching of arsenic from the ash below the 5 mg/L TCLP limit and retaining copper at ...

FEMS Microbiology Letters, 2022

This study examined the water-to-air transfer and viability of the fecal indicator bacteria, ente... more This study examined the water-to-air transfer and viability of the fecal indicator bacteria, enterococci, and compared capture performance of an impactor and aerosol filter. Results show that concentrations of viable enterococci collected by the impactor (70.1 CFU/L) was lower than that using the filter (171.2 CFU/L) at 95% significance. Between the impactor and filter, coefficients of variation equaled 13 and 14%, respectively. Hence, for the collection of aerosolized enterococci in a controlled environment, use of the aerosol filter yielded significantly higher recovery relative to impaction, though equally variable data were collected by both methods. This work confirms that viable enterococci transfer across a simulated air-sea interface and that aerosol filters perform well in capturing viable bacteria. Results from this study are relevant to studies that measure environmentally generated aerosols such as those that occur via wave breaking from sewage contaminated waters.

International Oil Spill Conference Proceedings, 2021

Marine oil spill incidents create concerns about human health risks, particularly in nearshore lo... more Marine oil spill incidents create concerns about human health risks, particularly in nearshore locations such as beaches used for recreation. To improve the timeliness of risk estimates during an oil spill, we need to expand modelling capacity for oil spill chemicals (OSCs) from predictions for chemical bulk measurements such as Total Petroleum Hydrocarbons (TPH) to predictions of individual concentrations of the more toxic Polycyclic Aromatic Hydrocarbons (PAH)s. The objective of this study is to establish a relationship for TPH and PAH nearshore sampling concentration values with the oil mass landing and TPH hindcast from a 3D Hydrodynamic Fate and Transport Model (3D-FTM) for a past oil spill. The overall goal is to use this information to expand current modeling capacities to predict concentration distributions for individual PAHs as a starting point for health risk assessment. During Phase I of this study, historic sampling data for various matrices (weathered oil, seawater and...

Journal of Biomolecular Techniques : JBT, 2021

The COVID-19 pandemic has had a profound, detrimental effect on economies and societies worldwide... more The COVID-19 pandemic has had a profound, detrimental effect on economies and societies worldwide. Where the pandemic has been controlled, extremely high rates of diagnostic testing for the SARS-CoV-2 virus have proven critical, enabling isolation of cases and contact tracing. Recently, diagnostic testing has been supplemented with wastewater measures to evaluate the degree to which communities have infections. Whereas much testing has been done through traditional, centralized, clinical, or environmental laboratory methods, point-of-care testing has proven successful in reducing time to result. As the pandemic progresses and becomes more broadly distributed, further decentralization of diagnostic testing will be helpful to mitigate its spread. This will be particularly both challenging and critical in settings with limited resources due to lack of medical infrastructure and expertise as well as requirements to return results quickly. In this article, we validate the tiny isothermal nucleic acid quantification system (TINY) and a novel loop-mediated isothermal amplification (LAMP)-based assay for the point-of-care diagnosis of SARS-CoV-2 infection in humans and also for in-the-field, point-of-collection surveillance of wastewater. The TINY system is portable and designed for use in settings with limited resources. It can be powered by electrical, solar, or thermal energy and is robust against interruptions in services. These applied testing examples demonstrate that this novel detection platform is a simpler procedure than reverse-transcription quantitative polymerase chain reaction, and moreover, this TINY instrument and LAMP assay combination has the potential to effectively provide both point-of-care diagnosis of individuals and point-of-collection environmental surveillance using wastewater.

Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Civil and Environmental Engineer... more Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Civil and Environmental Engineering, 1995.Includes bibliographical references (v. 1, p. 421-431).by Helena Solo-Gabriele.Ph.D

Humans may be exposed to microbial pathogens at recreational beaches via environmental sources su... more Humans may be exposed to microbial pathogens at recreational beaches via environmental sources such as water and sand. Although infectious disease risk from exposure to waterborne pathogens, and the fecal indicator bacteria (FIB) used to monitor water quality are active areas of research, sand is a relatively unexplored reservoir of pathogens and FIB. Sand and water at beaches experience continuous exchange of microorganisms, and these habitats provide unique advantages and challenges to pathogen introduction, growth, and persistence. Models of FIB and pathogen fate and transport in beach habitats can aid prediction of the risk of infectious disease from recreational water use, but filling knowledge gaps is necessary for accurate modeling. Climate change predictions estimate an increase in global temperatures of 2.5 – 10° F, sea level rise, and intensification of storms and precipitation in some regions. Other global change factors like population growth and urbanization may exacerbate predicted impacts. These changes can alter microbial population dynamics in beach habitats, and may consequently affect the assumptions and relationships used in numerical models. We discuss literature on microbial population and transport dynamics in sand/beach habitats, with an emphasis on how climate change and other anthropogenic influences (e.g., land use, urbanization) should be considered when using and developing models

European Journal of Public Health, 2016

Environmental Mycology in Public Health, 2016

Abstract Sediment and sands are reservoirs for many fungal pathogens. Given the burden of fungal ... more Abstract Sediment and sands are reservoirs for many fungal pathogens. Given the burden of fungal illness worldwide, efforts are needed to document risks associated with sediment and sand contact. Areas of particular concern include public places that encourage children's contact with sand. The unique play activities of children put them at increased risk due to potential exposures through skin, ingestion, and inhalation. This chapter summarizes data needs in terms of the basic components of risk assessment, including hazard identification, exposure, dose–response, and risk characterization. A literature review of fungi detection in public parks, sandpits, and beach sands found that the most commonly detected fungal pathogens included species of Aspergillus , Candida , Chrysosporium , Cryptococcus , Microsporum , Penicillium , Trichophyton , and Trichosporon . Risk estimations would benefit from a review and analysis of dose–response data for these fungi as well as studies that evaluate the influence of abrasions and wounds on the adherence and uptake of fungi on the skin. Risk assessment would also benefit from improved exposure assessments through the documentation of children's play behaviors when in contact with sediment and sand. Given the definition of acceptable risk levels, which would depend upon the severity of the disease, allowable levels of fungi can be then computed to establish guidelines for sand fungal levels in public areas or recommendations for human conduct during and after play activities.

Environmental Impacts of Treated Wood, 2006

Florida Center for Solid and Hazardous Waste Management Report, 2003

Sorting of waste wood is an important process practiced at recycling facilities in order to detec... more Sorting of waste wood is an important process practiced at recycling facilities in order to detect and divert contaminants from recycled wood products. Contaminants of concern include arsenic, chromium and copper found in chemically preserved wood. The objective of this research was to evaluate the sorting efficiencies of both treated and untreated parts of the wood waste stream, and metal (As, Cr and Cu) mass recoveries by the use of automated X-ray fluorescence (XRF) systems. A full-scale system was used for experimentation. This unit consisted of an XRF-detection chamber mounted on the top of a conveyor and a pneumatic slide-way diverter which sorted wood into presumed treated and presumed untreated piles. A randomized block design was used to evaluate the operational conveyance parameters of the system, including wood feed rate and conveyor belt speed. Results indicated that online sorting efficiencies of waste wood by XRF technology were high based on number and weight of pieces (70-87% and 75-92% for treated wood and 66-97% and 68-96% for untreated wood, respectively). These sorting efficiencies achieved mass recovery for metals of 81-99% for As, 75-95% for Cu and 82-99% of Cr. The incorrect sorting of wood was attributed almost equally to deficiencies in the detection and conveyance/diversion systems. Even with its deficiencies, the system was capable of producing a recyclable portion that met residential soil quality levels established for Florida, for an infeed that contained 5% of treated wood.

Water

Wastewater reclamation and reuse have the potential to supplement water supplies, offering resili... more Wastewater reclamation and reuse have the potential to supplement water supplies, offering resiliency in times of drought and helping to meet increased water demands associated with population growth. Non-potable water reuse represents the largest potential reuse market. Yet, economic constraints for new water reuse infrastructure and safety concerns due to microbial water quality, especially viral pathogen exposure, limit the widespread implementation of water reuse. Cost-effective, real-time methods to measure or indicate the viral quality of recycled water would do much to instill greater confidence in the practice. This manuscript discusses advancements in monitoring and modeling viral health risks in the context of water reuse. First, we describe current wastewater reclamation processes and treatment technologies with an emphasis on virus removal. Second, we review technologies for the measurement of viruses, both culture- and molecular-based, along with their advantages and di...