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The U.S. Geological Survey Environmental Health Mission Area works to safeguard the Nation’s health, economy, and resources by leading science to understand and minimize exposures to toxicological and infectious disease agents in the environment.

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Science Feature Articles

Our Science Feature Articles highlight recent USGS environmental health science activities.

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USGS GeoHealth Newsletter

USGS GeoHealth Newsletter

The GeoHealth Newsletter provides information on new USGS environmental health science activities related to safeguarding the health of the environment, fish and wildlife, domesticated animals, and people.

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Investigating Lung Disease in Military Veterans
November 10, 2017

Six years ago, veterans returning from Iraq and Afghanistan had trouble breathing normally. The list of potential causes that soldiers were exposed to seemed endless: smoke from burn pits used for trash disposal, desert dust, diesel generator exhaust, humidity and temperature extremes, explosives, and city trash and sewage.

Aerial View of Lake Okeechobee
September 18, 2017

Every few days, a fleet of satellites orbiting 700 kilometers above the Earth scans the continental United States to help keep Americans safe. But these eyes in the sky aren’t seeking terrorists or enemy combatants: they scrutinize lakes to locate problems of the microbial variety, namely cyanobacteria.

Image shows varying pigment levels from a satellite perspective of lakes in the United States
June 19, 2017

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.

USGS specializes in science at the environment-health interface, by characterizing the processes that affect the interaction among the physical environment, the living environment, and people, and the resulting factors that affect ecological and human exposure to disease agents.

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Neonicotinoid pesticides act as agonists of nicotinic acetylcholine receptors
Date Published: March 21, 2017

The Challenge: Neonicotinoid pesticides act as agonists of nicotinic acetylcholine receptors (nAChRs) and are designed to be lethal to insects while theoretically posing little to no threat to vertebrates. The perceived safety of neonicotinoids has led to a sharp increase in their use in the United States and globally, since they were first introduced in 1994. The use of the neonicotinoid...

Dye deposition in yolk over time
Date Published: March 17, 2017

The Challenge: Endocrine active chemicals (EAC) are known to interfere with hormonally regulated physiological processes, thereby affecting signaling in the hypothalamic-pituitary-gonadal-liver (HPGL) axis and commonly resulting in reproductive dysfunction. Computational models that relate hormonal and genomic biomarkers within the HPGL axis to the reproductive cycle and ecologically relevant...

Subadult Japanese quail
Date Published: March 16, 2017

The Challenge: Wild birds are exposed throughout their lives to natural and synthetic chemicals that are present in the environment, many of which interfere with the animal’s physiological and developmental systems. Relative concentrations, routes, frequency, and the environment in which chemical exposure occurs will determine to a large extent the bird’s response. Well-designed avian field...

Laughing gull (Larus atricilla)
Date Published: March 15, 2017

The Challenge: Mercury is a highly toxic element found throughout our environment. Although it occurs naturally in some environments, human industrial pollution has greatly increased the amount of mercury and the range of environments in which mercury is found. Recent studies have confirmed clear differences in the sensitivity of various bird species to methylmercury. Because the causes of...

Short-Chain Chlorinated Paraffins (SCCPs)
Date Published: March 14, 2017

The Challenge: Short-Chain Chlorinated Paraffins (SCCPs) are complex technical mixtures of polychlorinated n-alkanes used in lubricants and coolants in metalworking, as flame retardants, and in paints, adhesives, sealants, textiles and polymeric materials, plastics and rubber. SCCPs are of concern because they are globally transported, bioaccumulate in wildlife and humans, and are...

Avian egg injection
Date Published: March 13, 2017

The Challenge: The use of flame retardants (FRs) as additives in a variety of consumer use products, including plastics, textiles, and electronics, is projected to continue and increase for the foreseeable future. Because of unanticipated environmental problems, some FRs have either been banned, restricted, or are being phased-out and replaced by other new and presumably safer FRs. Regrettably...

Radiograph illustrating soy bean seeds in crop and gastrointestinal tract
Date Published: January 25, 2017

The Challenge: Neonicotinoids are now the most widely applied class of insecticides in the United States, and are predominantly used in the form of seed treatments. Compared to invertebrates, neonicotinoids are less toxic to wildlife, although genotoxic, cytotoxic, immunological, behavioral and reproductive effects have been reported in studies with birds. At present, little is known about the...

Eisenoides lonnbergi, a native earthworm, found to contain extremely high concentrations of lead
Date Published: January 25, 2017

The Challenge: As a rule, plants and animals contain lower concentrations of lead than are present in soils that support them. Lead does not biomagnify along trophic levels in ecosystems but instead remains relatively immobile in soil. The exposure of wildlife to soil lead depends mainly on the incidental ingestion of soil. The native earthworm, Eisenoides lonnbergi, is anomalous in its...

Black-tailed prairie dog mortality
Date Published: December 19, 2016

The Challenge: Black-tailed prairie dogs are considered a keystone species for the prairie habitat. Many avian species are associated with black-tailed prairie dogs (Cynomys ludovicianus) in winter.  Raptors feed on prairie dogs and non-raptor avian species forage within prairie dog colonies.  However prairie dogs are also considered agricultural pests. The first generation anticoagulant...

Glacier Bay National Park
Date Published: October 26, 2016

Human dimensions in the context of natural resource management refers to the ways humans value natural resources, resource management preferences, and how humans affect or are affected by natural resource management decisions. Natural resource management and policy decisionmaking require incorporation of sound biological, social, and economic science. SEA scientists use tools, research methods...

Osprey Fledglings still in the nest
Date Published: September 19, 2016

The Challenge: Agricultural, industrial and urban activities have had major effects on waterbirds in Chesapeake and Delaware Bays. Some legacy pollutants (PCBs, organochlorine pesticides, flame retardants, metals) pose a potential threat to wildlife in some locations. Pharmaceuticals, personal care products, and endocrine disrupting compounds have been detected in water and fish tissue, yet...

American Kestrel (Falco sparverius)
Date Published: September 19, 2016

The Challenge: Anticoagulant rodenticides have been identified as being hazardous to predatory and scavenging birds on a global scale. Restrictions on the sale, distribution and packaging of some second generation anticoagulant rodenticides (e.g., brodifacoum, difethialone, bromadiolone and difenacoum) have been instituted by the US EPA, and will likely result in expanded use of first-...

The Environmental Health Mission Area develops methods and tools to measure and assess the environmental health of watersheds and the organisms living in them. Our investigations generate and interpret environmental contaminant, biological activity, and effects data. All of which is provided to the public in our publications.

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Pharmaceuticals in water, fish, and ospreys nesting in Delaware River and Bay
October 19, 2017

Pharmaceuticals in water, fish, and ospreys nesting in Delaware River and Bay

Exposure of wildlife to Active Pharmaceutical Ingredients (APIs) is likely to occur but evidence of hazard and risk is limited. One exposure pathway that has received attention is trophic transfer of APIs in a water-fish-osprey food chain. 

Scientists collecting data in the Conasauga River, GA
October 19, 2017

Toxicity Assessment of Sediments Collected Upstream and Downstream of the White Dam in Clarke County, Georgia

A breach in the White Dam has been proposed to facilitate fish passage. As a Technical Assistance project, the U.S. Geological Survey provided toxicity assessments of sediment samples collected by USEPA personnel. 

Historic lead mine in southeastern Missouri
October 19, 2017

Exposure of Peromyscus leucopus to lead and cadmium in the Southeast Missouri Lead Mining District

The exposure of white-footed mice (Peromyscus leucopus) to lead and cadmium and the potential associated toxic effects were examined at three sites contaminated with lead in the Southeast Missouri Lead Mining District and at a reference site. 

Conasauga River, Georgia
October 19, 2017

Nutrient levels in surface waters of the Conasauga River and other tributaries within the Coosa River Watershed

Data Release for Report describes surface-water nutrient concentrations from multiple sites on the Conasauga River in northern Georgia in comparison with rivers in adjacent watersheds

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Screen capture of the The SCoRR Mapping Application
March 15, 2016

The Sediment-bound Contaminant Resiliency and Response (SCoRR) Mapping Application was developed to allow users to visualize and view information generated during this study. Additional datasets including Census data, the National Land Cover Database, and National Hydrography data are also provided for users to generate custom maps.

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Year Published: 2017

Contact and contagion: Probability of transmission given contact varies with demographic state in bighorn sheep

Understanding both contact and probability of transmission given contact are key to managing wildlife disease. However, wildlife disease research tends to focus on contact heterogeneity, in part because the probability of transmission given contact is notoriously difficult to measure. Here, we present a first step towards empirically investigating...

Manlove, Kezia R.; Cassirer, E. Frances; Plowright, Raina K.; Cross, Paul C.; Hudson, Peter J.

Year Published: 2017

Gene transcription patterns in response to low level petroleum contaminants in Mytilus trossulus from field sites and harbors in southcentral Alaska

The 1989 Exxon Valdez oil spill damaged a wide range of natural resources, including intertidal communities, and post-spill studies demonstrated acute and chronic exposure and injury to an array of species. Standard toxicological methods to evaluate petroleum contaminants have assessed tissue burdens, with fewer assays providing...

Bowen, Lizabeth; Miles, A. Keith; Ballachey, Brenda E.; Waters, Shannon C.; Bodkin, James L.; Lindeberg, Mandy; Esler, Daniel N.
Bowen, L, AK Miles, B Ballachey, S Waters, J Bodkin, M Lindeberg, D Esler. 2017. Gene transcription patterns in response to low level petroleum contaminants in Mytilus trossulus from field sites and harbors in southcentral Alaska. Deep Sea Research Part II: Topical Studies in Oceanography. doi: 10.1016/j.dsr2.2017.08.007

Year Published: 2017

Mass mortality attributed to acanthocephaliasis at a Gull-billed Tern (Gelochelidon nilotica) colony in coastal California

From 12 May 2013 to 29 May 2013, the Gull-billed Tern (Gelochelidon nilotica) colony at the San Diego Bay National Wildlife Refuge, California, experienced a mass die-off of at least 92 adults, representing 71–92% of the breeding population on the US west coast. Cause of death was determined to be peritonitis due to perforations of the intestine...

Patton, Robert T.; Goodenough, Katharine S.; De La Cruz, Susan; Nevins, HannahRose M.; Cole, Rebecca A.; Bodenstein, Barbara; Shearn-Bochsler, Valerie I.; Collins, Brian; Beck, Jessie; Sadowski, Matthew; Takekawa, John Y.
Patton, RT, KS Goodenough, SEW De La Cruz, H Nevins, R Cole, B Bodenstein, V Shearn-Bochsler, B Collins, J Beck, M Sadowski, JY Takekawa. 2017. Mass Mortality Attributed to Acanthocephaliasis at a Gull-Billed Tern (Gelochelidon nilotica) Colony in Coastal California. Journal of Wildlife Diseases. doi: 10.7589/2016-11-258

Year Published: 2017

Seroprevalence of Baylisascaris procyonis infection among humans, Santa Barbara County, California, USA, 2014–2016

Baylisascaris procyonis (raccoon roundworm) infection is common in raccoons and can cause devastating pathology in other animals, including humans. Limited information is available on the frequency of asymptomatic human infection. We tested 150 adults from California, USA, for B. procyonis antibodies; 11 were seropositive,...

Weinstein, Sara B.; Lake, Camille M.; Chastain, Holly M.; Fisk, David; Handali, Sukwan; Kahn, Philip L.; Montgomery, Susan P.; Wilkins, Patricia P.; Kuris, Armand M.; Lafferty, Kevin D.
Weinstein, SB, CM Lake, HM Chastain, D Fisk, S Handali, PL Kahn, SP Montgomery, PP Wilkins, AM Kuris, KD Lafferty. 2017. Seroprevalence of Baylisascaris procyonis Infection among Humans, Santa Barbara County, California, USA, 2014–2016. Emerging Infectious Diseases 23(8): 1397-1399. doi: 10.3201/eid2308.170222

Year Published: 2017

Maternal transfer of mercury to songbird eggs

We evaluated the maternal transfer of mercury to eggs in songbirds, determined whether this relationship differed between songbird species, and developed equations for predicting mercury concentrations in eggs from maternal blood. We sampled blood and feathers from 44 house wren (Troglodytes aedon) and 34 tree swallow (Tachycineta bicolor) mothers...

Ackerman, Joshua T.; Hartman, C. Alex; Herzog, Mark
Ackerman, JT, CA Hartman, MP Herzog. 2017. Maternal transfer of mercury to songbird eggs. Environmental Pollution 230: 463-468. doi: 10.1016/j.envpol.2017.06.099

Year Published: 2017

Trace element contamination in feather and tissue samples from Anna’s hummingbirds

Trace element contamination (17 elements; Be, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Se, Mo, Cd, Ba, Hg, Tl, and Pb) of live (feather samples only) and deceased (feather and tissue samples) Anna's hummingbirds (Calypte anna) was evaluated. Samples were analyzed using inductively coupled plasma-mass spectrometry (ICP-MS; 17 elements) and atomic...

Mikoni, Nicole A.; Poppenga, Robert H.; Ackerman, Joshua T.; Foley, Janet E.; Hazlehurst, Jenny; Purdin, Güthrum; Aston, Linda; Hargrave, Sabine; Jelks, Karen; Tell, Lisa A.
Mikoni, NA, R Poppenga, JT Ackerman, J Foley, J Hazlehurst, G Purdin, L Aston, S Hargrave, K Jelks, LA Tell. 2017. Trace element contamination in feather and tissue samples from Anna’s hummingbirds. Ecological Indicators 80: 96-105. doi: 10.1016/j.ecolind.2017.04.053

Year Published: 2017

Widespread occurrence and potential for biodegradation of bioactive contaminants in Congaree National Park, USA

Organic contaminants with designed molecular bioactivity, such as pesticides and pharmaceuticals, originate from human and agricultural sources, occur frequently in surface waters, and threaten the structure and function of aquatic and terrestrial ecosystems. Congaree National Park in South Carolina (USA) is a vulnerable park unit due to its...

Bradley, Paul M.; Battaglin, William A.; Clark, Jimmy M.; Henning, Frank; Hladik, Michelle L.; Iwanowicz, Luke; Journey, Celeste A.; Riley, Jeffrey W.; Romanok, Kristin
Bradley, P.M., W.A. Battaglin, J.M. Clark, F.P. Henning, M.L. Hladik, L.R. Iwanowicz, C.A. Journey, J.W. Riley, and K.M. Romanok. 2017. Widespread Occurrence and Potential for Biodegradation of Bioactive Contaminants in Protected Wilderness of Congaree National Park, USA. Environmental Toxicology & Chemistry. https://doi.org/10.1002/etc.3873

Year Published: 2017

Occurrence and in vitro bioactivity of estrogen, androgen, and glucocorticoid compounds in a nationwide screen of United States stream waters

In vitro bioassays are sensitive, effect-based tools used to quantitatively screen for chemicals with nuclear receptor activity in environmental samples. We measured in vitro estrogen (ER), androgen (AR), and glucocorticoid receptor (GR) activity, along with a broad suite of chemical analytes, in streamwater from 35 well-characterized sites (3...

Conley, Justin M.; Evans, Nicola; Cardon, Mary C.; Rosenblum, Laura; Iwanowicz, Luke; Hartig, Phillip C.; Schenck, Kathleen M.; Bradley, Paul M.; Wilson, Vickie S.
Justin M. Conley, Nicola Evans, Mary C. Cardon, Laura Rosenblum, Luke R. Iwanowicz, Phillip C. Hartig, Kathleen M. Schenck, Paul M. Bradley, Vickie S. Wilson. 2017. Occurrence and in vitro bioactivity of estrogen, androgen, and glucocorticoid compounds in a nationwide screen of United States stream waters. Environmental Science & Technology. http://dx.doi.org/10.1021/acs.est.6b06515

Year Published: 2017

Geographic and temporal patterns of variation in total mercury concentrations in blood of harlequin ducks and blue mussels from Alaska

We compared total mercury (Hg) concentrations in whole blood of harlequin ducks (Histrionicus histrionicus) sampled within and among two geographically distinct locations and across three years in southwest Alaska. Blue mussels were collected to assess correlation between Hg concentrations in locally available forage and birds. Mercury...

Savoy, Lucas; Flint, Paul L.; Zwiefelhofer, Denny; Brant, Heather; Perkins, Christopher R.; Taylor, Robert J.; Lane, Oksana P.; Hall, Jefferson S.; Evers, David C.; Schamber, Jason
Savoy, L., Flint, P., Zwiefelhofer, D., Brant, H., Perkins, C., Taylor, R., Lane, O., Hall, J., Evers, D., and Schamber, J., 2017, Geographic and temporal patterns of variation in total mercury concentrations in blood of harlequin ducks and blue mussels from Alaska, vol. 117, no. 1-2, p. 178-183. Doi: 10.1016/j.marpolbul.2017.01.084

Year Published: 2017

Mercury and water level fluctuations in lakes of northern Minnesota

Large lake ecosystems support a variety of ecosystem services in surrounding communities, including recreational and commercial fishing. However, many northern temperate fisheries are contaminated by mercury. Annual variation in mercury accumulation in fish has previously been linked to water level (WL) fluctuations, opening the possibility of...

Larson, James H.; Maki, Ryan P; Christensen, Victoria G.; Sandheinrich, Mark B.; LeDuc, Jaime F.; Kissane, Claire; Knights, Brent C.
Larson, J.H., Maki, R.P., Christensen, V.G., Sandheinrich, M.B., LeDuc, J.F., Kissane, C., Knights, B.C. 2017. Mercury and water level fluctuations in lakes of northern Minnesota. bioRxiv. DOI: 10.1101/118638.

Year Published: 2017

Cyanide poisoning of a Cooper’s hawk (Accipiter cooperii)

A Cooper’s hawk (Accipiter cooperii) was found dead in a ditch leading from a heap leach pad at a gold mine in Nevada. Observations at autopsy included an absence of external lesions, traces of subcutaneous and coronary fat, no food in the upper gastrointestinal tract, and no lesions in the viscera. Cyanide concentrations (µg/g ww) were 5.04 in...

Franson, J. Christian

Year Published: 2017

Editor’s note

Heavy metal contamination at shooting ranges is well documented (e.g., Heier et al. 2009; Islam et al. 2016). Primarily lead, but also copper, zinc, and antimony often occur at high concentrations in shooting range soils; cadmium, nickel, silver, and arsenic may also be present (Cao et al. 2003; Islam et al. 2016). These metals represent a...

Schmitt, Christopher J.
Schmitt, C. J., 2016, Editor’s Note. Bulletin of Environmental Contamination and Toxicology, Online First 28 December 2016: 1-1

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Lake Erie algal bloom
2017 (approx.)
Landsat satellites captured this image of Lake Erie during a harmful algal bloom event.
July 6, 2017
Mountain lions, desert bighorn sheep, mule deer, and a variety of other wildlife live on and pass through the Nevada National Security Site each day. It’s a highly restricted area that is free of hunting and has surprisingly pristine areas.This 22-minute program highlights an extraordinary study on how mountain lions interact with their prey. It shows how the scientists use helicopters and...
Hydrologists doing field work near Farmington, NM
June 20, 2017
USGS NMWSC Hydrologists Johanna Blake and Jeb Brown attended the 2nd Annual Conference on Environmental Conditions of the Animas and San Juan Watersheds with Emphasis on Gold King Mine and other Mine Waste Issues in Farmington, NM from June 20-21. Johanna and Jeb presented on the USGS long-term monitoring work of continuous monitoring sondes, water quality, and sediment measurement. On June 22nd...
April 27, 2017
Corrosive groundwater, if untreated, can dissolve lead and other metals from pipes. National maps have been prepared to identify the occurrence of potentially corrosive groundwater in the U.S. These findings have the greatest implication for the 44 million people dependent on domestic wells for drinking water.
April 19, 2017
See the actual drone footage at: https://www.usgs.gov/media/videos/prescribed-burn-tall-timbers-research-... Footage of drone during a prescribed fire at Tall Timbers Research Station, Tallahassee, Florida (April 19, 2017).
2016 (approx.)
The Avian Influenza Transmission Risk Model web application depicts the intricate connections between 16 layers of administrative, environmental, and economic data in an application that runs inside a web browser. To view and manipulate the full web application, please visit http://www.pwrc.usgs.gov/ai . The full web application requires a web browser with a large amount of memory available. This...
2016 (approx.)
For more information on the movement of wild birds in Asia and how this relates to avian influenza viruses, see http://www.pwrc.usgs.gov/ai . The autumn migration routes of bar-headed geese captured before the 2008 breeding season at Qinghai Lake, China, were documented using satellite tracking data. Our results showed that there were four typical migration routes in autumn with variation in...
2016 (approx.)
For more information on avian influenza, see http://www.pwrc.usgs.gov/ai . Two currently circulating avian influenza viruses, highly pathogenic A(H5N1) and low pathogenic A(H7N9) (hereafter H5N1 and H7N9) are of particular concern due to their high case-fatality rates (approximately 60 and 30% currently), and economic impact to the livestock industry and public health system. H5N1 first emerged...
Scientists Andrew Ramey, Bjorn Olsen, and Jonas Bonnedahl (L to R) setting a trap for gulls at the Soldotna landfill in 2016.
2016 (approx.)
Scientists Andrew Ramey, Bjorn Olsen, and Jonas Bonnedahl (L to R) setting a trap for gulls at the Soldotna landfill in June 2016.
Gulls using beach at the mouth of Kenai River during the personal use dipnet fishery for sockeye salmon.
2016 (approx.)
Gulls using beach at the mouth of Kenai River during the personal use dipnet fishery for sockeye salmon; photo taken during sampling trip in July 2016.
John Reed (USGS scientist) holding a gull marked with a satellite transmitter at the Soldotna landfill in June 2016
2016 (approx.)
John Reed (USGS scientist) holding a gull marked with a satellite transmitter at the Soldotna landfill in June 2016.

In addition to news releases on our latest papers, we provide Science Feature Articles that highlight results from environmental health science activities across the U.S. Geological Survey.

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Investigating Lung Disease in Military Veterans
November 10, 2017

Six years ago, veterans returning from Iraq and Afghanistan had trouble breathing normally. The list of potential causes that soldiers were exposed to seemed endless: smoke from burn pits used for trash disposal, desert dust, diesel generator exhaust, humidity and temperature extremes, explosives, and city trash and sewage.

Aerial View of Lake Okeechobee
September 18, 2017

Every few days, a fleet of satellites orbiting 700 kilometers above the Earth scans the continental United States to help keep Americans safe. But these eyes in the sky aren’t seeking terrorists or enemy combatants: they scrutinize lakes to locate problems of the microbial variety, namely cyanobacteria.

Image shows varying pigment levels from a satellite perspective of lakes in the United States
June 19, 2017

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.

Image: Vegetation Drought
June 5, 2017

The U. S. Geological Survey is poised to bring a dynamic array of science and tools to help decision-makers manage and offset effects of increased drought across the United States, according to a drought plan report released today.

Prescribed Burn at Tall Timbers Research Station
May 24, 2017

U.S. Geological Survey scientists and partners are taking technology to the next level, using unmanned aircraft systems (UAS), commonly called drones, to acquire both fire intensity and emissions data during prescribed burns.

Dr. Christian Zimmerman, USGS Alaska Science Center Director
February 1, 2017

The U.S. Geological Survey is pleased to announce the selection of Dr. Christian Zimmerman as the new director of their Alaska Science Center in Anchorage, Alaska. Zimmerman succeeds Dr. Mark Shasby who held the position for the past six years.

This picture was taken June 23, 2010 along the Louisiana shoreline in Barataria Bay and shows oil spilled from Deepwater Horizon
November 17, 2016

A new USGS-NASA study found widespread shoreline loss along heavily oiled areas of Louisiana's coast after the 2010 BP Deepwater Horizon oil spill and compared the erosion from the spill with coastal changes Hurricane Isaac caused in 2012.

Cyanobacterial bloom in Lake Okeechobee, FL (July 2016)
October 24, 2016

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