Keith A Loftin, Ph.D.
Science and Products
Review of Cyanobacterial Neurotoxins—Information for Prioritizing Future Science Directions
The current state of knowledge on the modes of action, production, fate, and occurrence of the freshwater cyanobacterial neurotoxins, anatoxin-a and saxitoxin, was reviewed and synthesized to identify gaps and critical research needs to better understand the health effects of algal toxins.
Satellite Data Used to Estimate and Rank Cyanobacterial Bloom Magnitude in Florida and Ohio Lakes—Developing Tools to Protect Human and Wildlife Health from Cyanotoxin Exposure
Cyanobacterial bloom magnitude during 2003–11 was quantified and ranked in Florida and Ohio lakes with a newly developed modelling tool that allows for the use of multiple satellite data sources and user-defined thresholds. This tool was designed to identify the magnitude of algal blooms, but one metric alone cannot adequately represent the severity of a bloom of interest in terms of toxicity...
Mixtures of Algal Toxins Present Prior to and After Formation of Visible Algal Blooms—Science to Inform the Timing of Algal Toxin Exposure
Cyanobacteria with toxin-producing potential, genes indicating an ability for toxin synthesis, or cyanotoxins were present before and after formation of a visible algal bloom in Kabetogama Lake, a popular recreation area in Voyageurs National Park that lies along the border of Minnesota and Canada. The temporal patterns observed in this study indicate that sampling only when there is a visible...
The Influence of Aerosols on Harmful Algal Toxin Production and Maintenance
The primary objective of this study is to determine what aerosol events (desert dust storms, volcanic eruptions, fires) or pathways contribute to the propagation of harmful algal toxins. This study provides insight into what type of aerosol events contribute to harmful algal blooms.
Understanding Drivers of Cyanotoxin Production in the Lake Okeechobee Waterway
The U.S. Geological Survey (USGS) and other researchers combined field and laboratory approaches in two studies to understand the factors that drive cyanobacterial bloom development and associated cyanotoxin production in Lake Okeechobee, the St. Lucie River and Estuary, and the Indian River Lagoon in response to the large-scale Lake Okeechobee cyanobacteria bloom in 2016.
Toxins and Harmful Algal Blooms Science Team
The team develops advanced methods to study factors driving algal toxin production, how and where wildlife or humans are exposed to toxins, and ecotoxicology. That information is used to develop decision tools to understand if toxin exposure leads to adverse health effects in order to protect human and wildlife health....
Understanding Associations between Mussel Productivity and Cyanotoxins in Lake Erie
Study findings indicate that cyanobacteria and cyanotoxins were not associated with mussel mortality at the concentrations present in Lake Erie during a recent study (2013-15), but mussel growth was lower at sites with greater microcystin concentrations.
New Method Developed to Quantify Spatial Extent of Cyanobacterial Blooms
This study provides a method for quantifying changes in the spatial extent of cyanobacterial blooms at local and regional scales using remotely sensed data to determine if bloom occurrence and size are increasing or decreasing for inland water resources.
Satellite Imagery Used to Measure Algal Bloom Frequency—Steps Toward Understanding Exposure Risk
Study explores the utility and limitations of currently available remotely sensed satellite data for identifying the frequency of algal blooms in the Nation's lakes and reservoirs. This information provides a first step toward the goal of understanding exposure risk to protect the health of humans, pets, livestock, and wildlife.
Cyanobacteria from 2016 Lake Okeechobee Harmful Algal Bloom Photo-Documented
New report provides photographic documentation and identification of the cyanobacteria present in Lake Okeechobee, the Caloosahatchee River, and St. Lucie Canal during an extensive algal bloom in 2016.
Evaluating Linkages Between Algal Toxins and Human Health
The amino acid β-methylamino-L-alanine (BMAA) is produced by cyanobacteria and has been suggested by human health researchers as a causal factor for degenerative neurological diseases such as Amyotrophic Lateral Sclerosis (ALS), Parkinsonism, and dementia. An objective review concluded that this hypothesis is not supported by existing data.
USGS Scientist Receives Award for Assistance with National Wetlands Assessment
U.S. Geological Survey (USGS) scientist Dr. Keith A. Loftin received the U.S. Environmental Protection Agency (EPA) Office of Water's Achievement in Science and Technology Award for his contributions to the National Wetlands Condition Assessment.
Ecological forecasting—21st century science for 21st century management
Natural resource managers are coping with rapid changes in both environmental conditions and ecosystems. Enabled by recent advances in data collection and assimilation, short-term ecological forecasting may be a powerful tool to help resource managers anticipate impending near-term changes in ecosystem conditions or dynamics. Managers may use the...
Bradford, John B.; Weltzin, Jake F.; Mccormick, Molly; Baron, Jill; Bowen, Zack; Bristol, Sky; Carlisle, Daren; Crimmins, Theresa; Cross, Paul; DeVivo, Joe; Dietze, Mike; Freeman, Mary; Goldberg, Jason; Hooten, Mevin; Hsu, Leslie; Jenni, Karen; Keisman, Jennifer; Kennen, Jonathan; Lee, Kathy; Lesmes, David; Loftin, Keith; Miller, Brian W.; Murdoch, Peter; Newman, Jana; Prentice, Karen L.; Rangwala, Imtiaz; Read, Jordan; Sieracki, Jennifer; Sofaer, Helen; Thur, Steve; Toevs, Gordon; Werner, Francisco; White, C. LeAnn; White, Timothy; Wiltermuth, Mark
Characterization of water-quality and bed-sediment conditions in Currituck Sound, North Carolina, prior to the Mid-Currituck Bridge construction, 2011–18
The North Carolina Turnpike Authority plans to improve transportation in the Currituck Sound area by constructing a two-lane bridge—the Mid-Currituck Bridge—across Currituck Sound from the mainland to the Outer Banks, North Carolina. The results of the final environmental impact statement for the project indicate potential water-quality and...
Harden, Stephen L.; Fitzgerald, Sharon A.; Wagner, Chad R.; Bristow, Emilia L.; Loftin, Keith A.; Rosen, Barry H.
Mixed organic and inorganic tapwater exposures and potential effects in greater Chicago area, USA
Safe drinking water at the point of use (tapwater, TW) is a public-health priority. TW exposures and potential human-health concerns of 540 organics and 35 inorganics were assessed in 45 Chicago area United States (US) homes in 2017. No US Environmental Protection Agency (EPA) enforceable Maximum Contaminant Level(s) (MCL) were exceeded in any...
Bradley, Paul; Argos, Maria; Kolpin, Dana W.; Meppelink, Shannon M.; Romanok, Kristin; Smalling, Kelly; Focazio, Michael J.; Allen, Joshua M.; Dietze, Julie E.; Devito, Michael J.; Donovan, Ariel; Evans, Nicola; Givens, Carrie E.; Gray, James L.; Higgins, Christopher P.; Hladik, Michelle; Iwanowicz, Luke; Journey, Celeste A.; Lane, Rachael; Laughrey, Zachary; Loftin, Keith A.; McCleskey, R. Blaine; McDonough, Carrie A.; Medlock Kakaley, Elizabeth K; Meyer, Michael T.; Holthouse-Putz, Andrea; Richardson, Susan D; Stark, Alan ; Weis, Christopher P.; Wilson, Vickie S.; Zehraoui, Abderrahman Measurement of cyanobacteria bloom magnitude using satellite remote sensing
Cyanobacterial harmful algal blooms (cyanoHABs) are a serious environmental, water quality and public health issue worldwide because of their ability to form dense biomass and produce toxins. Models and algorithms have been developed to detect and quantify cyanoHABs biomass using remotely sensed data but not for quantifying bloom magnitude,...
Mishra, Sachidananda; Stumpf, Richard P. ; Schaeffer, Blake ; Werdell, P. Jeremy ; Loftin, Keith A.; Meredith, Andrew The presence of antibiotic resistance genes in coastal soil and sediment samples from the eastern seaboard of the USA
Infections from antibiotic resistant microorganisms are considered to be one of the greatest global public health challenges that result in huge annual economic losses. While genes that impart resistance to antibiotics (AbR) existed long before the discovery and use of antibiotics, anthropogenic uses of antibiotics in agriculture, domesticated...
Griffin, Dale W.; Benzel, William M.; Fisher, Shawn C.; Focazio, Michael J.; Iwanowicz, Luke R.; Loftin, Keith A.; Reilly, Timothy J.; Jones, Daniel K. Organic geochemistry and toxicology of a stream impacted by unconventional oil and gas wastewater disposal operations
Water and sediment extracts samples were analyzed for extractable hydrocarbons by gas chromatography/mass spectrometry (GC/MS) using an Agilent (Agilent Technologies, Palo Alto, CA, USA) 7890 series GC and 5975 electron ionization (EI) mass selective detector (MSD) operated in scan mode. Agilent ChemStation software was used for data acquisition...
Orem, William H.; Varonka, Matthew S.; Crosby, Lynn M.; Haase, Karl B.; Loftin, Keith A.; Hladik, Michelle; Akob, Denise M.; Tatu, Calin; Mumford, Adam C.; Jaeschke, Jeanne B.; Bates, Anne L.; Schell, Tiffani; Cozzarelli, Isabelle M.
Methods used for the collection and analysis of chemical and biological data for the Tapwater Exposure Study, United States, 2016–17
In 2016, the U.S. Geological Survey (USGS) Environmental Health Mission Area, initiated the Tapwater Exposure Study as part of an infrastructure project to assess human exposure to potential threats from complex mixtures of contaminants. In the pilot phase (2016), samples were collected from 11 States throughout the United States, and in the...
Romanok, Kristin M.; Kolpin, Dana W.; Meppelink, Shannon M.; Argos, Maria; Brown, Juliane B.; Devito, Michael J.; Dietze, Julie E.; Givens, Carrie E.; Gray, James L.; Higgins, Christopher P.; Hladik, Michelle L.; Iwanowicz, Luke R.; Loftin, Keith A.; McCleskey, R. Blaine; McDonough, Carrie A.; Meyer, Michael T.; Strynar, Mark J.; Weis, Christopher P.; Wilson, Vickie S.; Bradley, Paul M.
Understanding the effect of salinity tolerance on cyanobacteria associated with a harmful algal bloom in Lake Okeechobee, Florida
In an effort to simulate the survival of cyanobacteria asthey are transported from Lake Okeechobee to the estuarinehabitats that receive waters from the lake, a bioassayencompassing a range of salinities was performed. An overalldecline in cyanobacteria health in salinity treatments greaterthan 18 practical salinity units (psu) was indicated by...
Rosen, Barry H.; Loftin, Keith A.; Graham, Jennifer L.; Stahlhut, Katherine N.; Riley, James M.; Johnston, Brett D.; Senegal, Sarena
Water-quality conditions with an emphasis on cyanobacteria and associated toxins and taste-and-odor compounds in the Kansas River, Kansas, July 2012 through September 2016
Cyanobacteria cause a multitude of water-quality concerns, including the potential to produce toxins and taste-and-odor compounds that may cause substantial economic and public health concerns, and are of particular interest in lakes, reservoirs, and rivers that are used for drinking-water supply. Extensive cyanobacterial blooms typically do not...
Graham, Jennifer L.; Foster, Guy M.; Williams, Thomas J.; Mahoney, Matthew D.; May, Madison R.; Loftin, Keith A. Book review: Handbook of cyanobacterial monitoring and cyanotoxin analysis
Review of Meriluoto, Jussi, Lisa Spoof, and GeoffreyA. Codd [eds.]. 2017. Handbook of Cyanobacterial Monitoring and Cyanotoxin Analysis. John Wiley & Sons, Ltd.: Chichester, West Sussex, UK, ISBN 978‐1‐119‐06868‐6 (978‐1‐119‐06876‐1 eBook), DOI 10.1002/9781119068761.
Graham, Jennifer L.; Loftin, Keith A. Associations between cyanobacteria and indices of secondary production in the western basin of Lake Erie
Large lakes provide a variety of ecological services to surrounding cities and communities. Many of these services are supported by ecological processes that are threatened by the increasing prevalence of cyanobacterial blooms which occur as aquatic ecosystems experience cultural eutrophication. Over the past 10 yr, Lake Erie experienced...
Larson, James H.; Evans, Mary Anne; Kennedy, Robert J.; Bailey, Sean; Loftin, Keith A.; Laughrey, Zachary; Femmer, Robin; Schaeffer, Jeff; Richardson, William B.; Wynne, Timothy; Nelson, J. C.; Duris, Joseph W.
Detection of microcystin and other cyanotoxins in lakes at Isle Royale National Park, Pictured Rocks National Lakeshore, and Sleeping Bear Dunes National Lakeshore, northern Michigan, 2012–13
Although cyanotoxins released during algal blooms have become an increasing concern in surface waters across the United States, the presence of cyanotoxins in northern Michigan lakes had not been evaluated in detail. The U.S. Geological Survey and National Park Service (NPS) led a 2-year study (2012 and 2013) to determine the presence of...
Fuller, Lori M.; Brennan, Angela K.; Fogarty, Lisa R.; Loftin, Keith A.; Johnson, Heather E.; VanderMeulen, David D.; Lafrancois, Brenda Moraska
Satellite Imagery Can Track Harmful Algal Blooms
A joint collaboration between EPA, NOAA, NASA, and USGS scientists has demonstrated that satellite imagery can be used to track the frequency of harmful algal blooms. The satellites can accomplish this by measuring certain algal pigments in the water.
New Science Challenges Old Assumptions about Harmful Algal Blooms
First-of-its-kind survey shows that algal toxins are found nationwide
Multiple Satellite Eyes to Track Algal Threat to U.S. Freshwater
Four federal agencies including the U.S. Geological Survey have joined forces in an effort to transform satellite data into vital information to protect the American public from freshwater contaminated by harmful algal blooms.