by Dana Stephens | Jul 7, 2025
PFAS—have you heard of them? Do you know what they are, or is it more of a term thrown around without much context?
PFAS are per- and polyfluoroalkyl substances. PFAS is a class of chemicals found in various industrial and consumer goods. For instance, you may find them in food packaging, textiles, cosmetics, and frequently in aqueous film-forming foams (AFFFs) used to extinguish fires. PFAS chemicals are known for repelling grease, water, and stains, making them widely used in various applications. These chemicals are stable and persistent, earning them the nickname “forever chemicals” because they do not readily biodegrade, or break down easily in the environment.
Numerous researchers suggested PFAS are abundant in aquatic systems and toxic to a range of aquatic organisms, with additional concerns of bioaccumulation of PFAS. PFAS accumulate in sediments and aquatic organisms, which pose health risks to wildlife and humans through the food chain. Research suggests linkages of PFAS to disruption of endocrine function, reproduction, and development in aquatic organisms. Research suggests similar linkages of PFAS to humans, like increased cancer risk, immune system suppression, endocrine and reproductive disruption, and child developmental concerns.
The United States Geological Survey (USGS) estimated at least 45% of the United States’ tap water has one or more PFAS chemicals (Smalling et al. 2023). At least one PFAS was identified in 60% of public wells and 20% of domestic wells supplying drinking water in the eastern United States (McMahon et al. 2022).
Have PFAS been found in Okaloosa County drinking water and surface waters?
Measured PFAS in Florida and Okaloosa County Drinking Waters
Figure 1. Map with measured total PFAS samples across a gradient of low concentrations (green dots) to medium concentrations (yellow dots) to higher concentrations (red dots). Shaded map colors are the predicted total PFAS using estimated values of PFAS concentrations from low (green) to high (red). Data, figure, and result interpolation from Sinkway et al. 2024.
A team of researchers completed a comprehensive statewide assessment of PFAS in Florida drinking water (Sinkway et al. 2024). The team collected 448 drinking water samples across all 67 Florida counties. The drinking water samples were analyzed for 31 PFAS, where 19 PFAS were found in at least one drinking water sample. The top five most frequently detected PFAS were 6:2 fluorotelomer sulfonate (6:2 FTS) (in 84% of the samples analyzed), Perfluorooctanoic acid (PFOA) (65%), linear perfluorooctane sulfonate (PFOS) (65%), branched PFOS (64%), and perfluorobutane sulfonic acid (PFBS).
A total of 107 taps had PFOA or PFOS concentrations above 4 ng/L (ppt), where the maximum total PFAS concentration in a tap was 219 ng/L (Click on link for higher resolution–Figure 1). The maximum contaminant level for PFOA and PFOS is 4 ng/L, legally enforced by the United States Environmental Protection Agency National Primary Drinking Water Regulation as of May 14, 2025 (USEPA, 2025). Overall, 8% of the drinking water samples analyzed exceeded 4 ng/L for PFOA and 16% for PFOS. The average total PFAS in city water was 15.6 ng/L, and in well water was 4.5 ng/L.
Table 1. Top average 12 Florida counties with highest and lowest total PFAS concentrations (ng/L). Data, figure, and result interpolation from Sinkway et al. 2024.
Okaloosa County had the 11th highest total PFAS (ng/L) concentration among the 67 Florida counties (Click on link for higher resolution–Table 1). Among the eight drinking water samples collected, the maximum PFAS concentration measured was 140 ng/L, and the lowest was 18 mg/L. Okaloosa County had one drinking water sample that exceeded the 4 ng/L standard for PFOA. There were no drinking water samples that exceeded 4 ng/L for PFOS.
Measured PFAS in Florida and Okaloosa County Surface Waters
A team of researchers completed a comprehensive statewide assessment of PFAS in Florida surface waters (Camacho et al. 2024). A network of citizen scientists collected 2,323 surface water samples across the 67 Florida counties. These surface water samples were analyzed for 50 PFAS, with 33 PFAS being detected in at least one surface water sample. The top five most frequently detected PFAS were perfluorooctanoic acid (PFOA) (94% of the samples), perfluorobutane sulfonic acid (PFBS) (65%), perfluorohexanoic acid (PFHxA) (61%), perfluorononanoic acid (PFNA) (54%), and perfluorooctane sulfonate (PFOS) (53%).
Figure 2. Map A contains all surface water sampled sites with detected PFAS, where the dots’ color represents the total PFAS concentration measured. Map B shows predicted PFAS levels based on measured total PFAS concentrations in surface water samples. Note that these values do not represent predicted PFAS concentrations on land. Data, figure, and result interpolation from Camacho et al. 2024.
There were 915 (39%) surface water samples with PFOA concentrations above 4 ng/L and 920 (40%) samples with PFOS above 4 ng/L (Click on link for higher resolution–Figure 2). All counties had at least one sample with PFOA, 96% had PFNA, 93% had PFBS, 91% had PFOS, and 82% of counties had PFHxA. The average PFAS detected among counties ranged from 2 ng/L of PFNA to 10 ng/L of PFOS. The maximum PFAS detected among counties ranged from 81 ng/L of PFOA to 1135 ng/L of PFOS. Figure 2
Okaloosa County ranked 27th among Florida counties due to 10 (20%) surface water samples with PFOA above 4 ng/L. Okaloosa County ranked 9th for the number of samples (38 total samples or 78% of the samples) above 4 ng/L for PFOS. A total of 49 surface water samples were collected in Okaloosa County. The average total PFAS concentration detected in a surface water sample was 31 ng/L, while the maximum total PFAS concentration detected in a sample was 185 ng/L.
Dr. Bowden, with the University of Florida’s College of Veterinary Medicine and Chemistry Department, led the PFAS research shared here. Dr. Bowden has extensive information on the Bowden Lab website (https://www.bowdenlaboratory.com/dr-bowden.html), including an interactive map of all the PFAS surface water samples collected in Florida. Select Okaloosa County under the filter section to see the surface water samples and learn more about the PFAS information for each sample collected in Okaloosa County (https://www.bowdenlaboratory.com/florida-surface-water.html).Figure 2 Table 1
What does this mean for Okaloosa County?
PFAS have been detected in drinking water and surface waters in Okaloosa County. Although not the highest concentrations or most frequent identified in Florida, there were drinking and surface water samples above USEPA’s 4 ng/L contaminant level standard. Understanding what PFAS are and joining in educational conversations about PFAS helps our community. Efforts that support continued sampling and extended monitoring also increase our understanding of PFAS concentrations in Okaloosa County’s drinking and surface waters. If you want to learn more about PFAS or join community scientists’ efforts to expand PFAS water monitoring, please contact Dana Stephens at the UF/IFAS Okaloosa County Extension Office.
References
Camacho, C.G., et al. 2024. Statewide surveillance and mapping of PFAS in Florida surface waters. American Chemical Society, 4: 434-4355. https://doi.org/10.1021/acsestwater
United States Environmental Protection Agency (USEPA). 2025. Per- and polyfluoroalkyl substances (PFAS) final PFAS national primary drinking water regulation. https://www.epa.gov/sdwa/and-polyfluoroalkyl-substances-pfas
McMahon, P.B., Tokranov, A.K., and Bexfield, L.M. 2022. Perfluoroalkyl and polyfluoroalkyl substances in groundwater used as a source of drinking water in the Eastern United States. Environmental Science and Technology 56(4): 2279-2288. https://doi.org/10.1021/acs.est.1c04795
Skinkway, T.D., et al. 2024. Crowdsourcing citizens for statewide mapping of per- and polyfluoroalkyl substances (PFAS) in Florida drinking water. Science of the Total Environment, 926: 1-9. https://doi.org/10.1016/j.scitotenv.2024.171932
by Dana Stephens | Jun 6, 2025
Li
onfish slayers, divers, fisherfolks, and ocean lovers joined for an exhilarating 2025 lionfish tournament and awareness festival last weekend at Harborwalk in Destin, Florida.
The Emerald Coast Open is the largest lionfish tournament in the world. Lionfish are venomous marine fishes native to the South Pacific and Indian Oceans, or the Indo-Pacific region. Lionfish found along the southeastern United States coast, including the Emerald Coast of Florida, are not native. Lionfish are considered invasive species in the southeastern United States. With few natural predators and an ability to outcompete native species, lionfish can cause damaging impacts to native fishes, crustaceans, and the oceanic ecosystem overall.
The Emerald Coast Open and numerous partners, including Florida Sea Grant, support the lionfish tournament as an effort to reduce the number of li
onfish along the Emerald Coast while educating and having fun. Amazing Emerald Coast volunteers (there were 35 this year) processed the lionfish—counting, weighing, and measuring. The lionfish are sold to buyers like restaurant owners who make delicious lionfish dishes, additionally spreading education about lionfish and lionfish as a yummy food source.
This year was a HUGE success! There were 7,180 lionfish brough in by 143 participants during the pre-tournament and an additional 13,322 lionfish during the main tournament. This means there was a total of 20,502 lionfish were removed from our local waters during the 2025 Emerald Coast Open!
Emerald Coast Open award categories included: most lionfish, biggest lionfish, smallest lionfish, guess the lionfish contest total, and restaurant week. Winners received $65,000 in cash prizes along with participant raffle for amazing prizes worth over $60,000. Winners for each category are listed here and on the Emerald Coast Open’s website and Facebook page.
\
M
ost Lionfish
1st– DWM1- 2038 lionfish
2nd– Reef Madness- 1256 lionfish
3rd – Shark Quest- 1034 lionfish
4th – Sea Meat- 1029 lionfish
5th – Rubber Duck- 965 lionfish
6th – Covered in Blood- 909 lionfish
7th – In the Clouds- 817 lionfish
8th– DWM Spinal Tap- 695 lionfish
9th– Zookeeper Slayers- 477 lionfish
10th-Black Flag- 457 lionfish
Largest Lionfish
1st– In the Clouds- 17.2 inches
2nd– All Riled Up- 17.1 inches
3rd – Off the Deep End- 16.9 inches
4th – Pilot Plunder and Pillage- 16.7 inches
5th – Fin Reapers- 16.6 inches
6th – Hookshott- 16.5 inches
7th – Down N Out- 16.4 inches
8th– Opted Out- 16.3 inches
9th– Tie- Covered in Blood- 16.2 inches
10th-Tie- Rum Fish- 16.2 inches
Smallest Lionfish
1st– Looking Back- 2.87 inches
2nd– Todd’s Team- 3.11 inches
3rd – Tie- In the Clouds- 3.14 inches
4th – Tie- Blue Bucket- 3.14 inches
5th – All Riled Up- 3.38 inches
6th – DWM1- 3.54 inches
7th – Smokediver- 3.62 inches
8th– Shark Quest- 3.66 inches
9th– Tie- Zookeeper Slayers- 3.74 inches
10th-Tie- Off the Deep End- 3.74 inches
Guess Lionfish Total
Carole Donaldson- Guessed 13,300, which was 22 less than the actual 13,322 total
Restaurant Week
1st– La Paz
2nd– Bitterroot
3rd– Beach Walk Café
by Dana Stephens | May 12, 2025
Spring is a time of change. Spring brings changes in our waters as well. Some of these changes are visible on top of the water and cause concern among water users and viewers. Let’s dispel some of these concerns associated with the spring season.
Sometimes, water users and viewers notice what appears to be oil floating on top of the water. Could this be oil? Potentially. Could this not be oil? Most likely. Plants perish, and decomposition occurs, typically during the spring and fall seasons of the year. Much of the decomposition that happens in spring is associated with the initial growth and development of plants. Bacteria living in the soils within and around the water break down the perished plants. These bacteria are decomposing the old plant material. The waste product produced from the bacteria’s decomposition of the old plant material is an oily substance. The oily sheen on the water is a waste product of bacteria. Frequently, the oil accumulates in portions of water where there is little to no water movement. As the decomposition process completes, the oily sheen should lessen over the next few days to weeks. This bacteria-produced oil from decomposition is a natural process.
Petroleum-based oil seen on water is not a natural process. Petroleum-based oil could enter water from various sources, such as but not limited to transportation spills, stormwater runoff, and improper disposal of products containing oil. Like the oily substances produced by bacteria during decomposition, petroleum-based oils will float on top of the water and accumulate where there is little to no water movement.
Here are some tips to identify the difference between oils in water:
|
Bacteria-produced Oil |
Petroleum-based Oil |
| Appearance |
Oily sheen on top of water with little to no difference in color throughout |
Oily sheen on top of water with differences in color throughout (may even appear like a rainbow) |
| Touch
(use a stick) |
When disturbed, the sheen breaks away easily with irregular patterns and does not reform. The oil will not adhere to the stick. |
When disturbed, the sheen swirls, elongates, and does reform. The oil may adhere to the stick. |
| Odor
(not always present) |
Strong organic, musty, or earthy smell. |
Volatile organic compounds (VOCs) smelling like gasoline or diesel fuel. |
Another sheen on our waters that is frequent during Florida’s springtime is pollen. Pine, tree, and weed pollen accumulate on top of water, especially in areas with little or no water movement. If the sheen on the water is yellow, orange, or sometimes white, this is most likely due to pollen. Think about how pollen shows on a car in Florida during spring…our waters can show the same to some extent.
Let’s give it a try! See if you can identify the sheens in water in each photo—answers at the bottom of the page.
Photo 1
Photo 2
Photo 3
Photo 4
Photo 5
Photo 6
Keep Scrolling For Answers!
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PHOTO ANSWERS: Photo 1: Bacteria-produced oil sheen. Photo 2: Pollen sheen. Photo 3: Petroleum-based oil sheen. Photo 4: Pollen sheen. Photo 5: Petroleum-based oil sheen. Photo 6: Mixture of bacteria-produced oil and pollen sheen. Note all photos were obtained from Adobe Stock Photos.
by Dana Stephens | Apr 11, 2025
Okaloosa Waterwatch is an opportunity to explore water quality data in selected locations spanning the Okaloosa County portion of the Choctawhatchee Bay.
A site is selected each month, and available water quality data are summarized and explained. The purpose is to understand water quality and the condition of our waters. Thanks to the Choctawhatchee Basin Alliance (CBA), water quality data has been collected frequently (monthly) for many years.
Below are the February and March Okaloosa Waterwatch water quality summaries. February highlights the mid-bay bridge (Niceville) location, and March highlights the entrance to Rocky Bayou (Niceville) location.
Check out the Okalooas Waterwatch YouTube channel for a personalized audio review of the water quality summaries. The YouTube channel is Okaloosa Waterwatch (@OkaloosaWaterwatch) or navigate directly using this link: https://www.youtube.com/channel/UCGPVMsyMiTU5BT9xyrFhuYQ
Please contact Dana Stephens, UF/IFAS Okaloosa County Sea Grant Extension Agent, for more information or to learn more about water quality in Okaloosa County. Email is dlbigham@ufl.edu and office phone is 850-689-5850.
Okaloosa Waterwatch February 2025 (PDF Link)
Okaloosa Waterwatch March 2025 (PDF Link)
by Dana Stephens | Aug 2, 2024
Do you know what is your watershed?
There was, is, and will be the same amount of water on planet Earth. Water is a finite resource. The United States Geologic Survey estimates Earth holds around 1,386,000,000 cubic kilometers of water. Only 330,520 cubic kilometers, less than 1% of all water on Earth, is freshwater. This freshwater is available in the soils, atmosphere, biosphere and used by humans.
We all have different connections with water. Maybe it is swimming. Maybe it is enjoyment of clean laundry. Maybe it is the iconic scenes in the 1992 Academy Award for Best Cinematography, A River Runs Through It. Yet, we all depend on water for life. How and why water moves across a landscape to sustain life is important to us all.
Watersheds in the Continental United States (usgs.gov)
Water located on land is called surface water. Water located underground is called groundwater. A watershed is the area of land where surface water and groundwater drain to a common place. Watersheds vary in size from as small as the size of your foot to as large as the watersheds spanning the continental United States. Larger watersheds are composed of smaller watersheds linked together.
Water gradually flows from higher to lower points in a watershed. Precipitation (i.e., snow, rain and everything in between) collects and moves within the drainage area in the watershed. Not all precipitation falling on a watershed flows out of the watershed. Precipitation soaks into the soil and through porous rock moving to lower points in the watershed, returning to and replenishing water stored underground. This groundwater can return to the surface of the watershed via springs or artesian wells, if the groundwater is under enough pressure.
Water can be removed before flowing out of the watershed as well. Precipitation returns to the atmosphere through evaporation as part of the hydrologic cycle. Plants facilitate evaporation to the atmosphere through transpiration where the roots of plants absorb water from the soil and the water evaporates into the air through the leaves of the plants. Human uses of water also impact how water moves through a watershed. Drinking water supplies, industrial operations, or building dams changes the movement of water through the watershed.
Each of us lives in a watershed. There is much benefit to have healthy watersheds. Healthy watersheds are essential to support ecosystems and the services provided, such as safe drinking water, outdoor recreation, economics, and overall quality of life. There are many metrics and assessments used to measure the health of a watershed. Do you know what is the health of your watershed?
United States Environmental Protection Agency’s How’s My Watershed interactive tool (http://mywaterway.epa.gov)
The United States Environmental Protection Agency developed “How’s My Waterway” to provide the public with information about the condition of their local waters. How’s My Waterway offers three ways to explore your watershed. At the community level, you can see your watershed with details like the water quality, recreation, fish consumption, impairments, and associated plans working to remove impairments. At the state and national levels, you can find information about states/national water program(s) and specific water assessment(s) that affect your watershed.
Example–watershed for Okaloosa County UF/IFAS Extension North office.
Let’s give it a try! Go to www.mywaterway.epa.gov in your web browser. Enter the desired address and select >>Go. On the left, you’ll see an interactive map outlining your watershed and the drainage basin(s) that make up the watershed. On the right, there are 10 different tabs allowing you to explore various metrics of the watershed. For example, there is a general tab reviewing the water conditions and states (i.e., good, impaired, or condition unknown) for all surface waters in the watershed. Using the arrow on the right, you can expand each water source to learn specifics about the data-determined state of the water.
Enjoy exploring your watershed! If you have questions about the interactive “How’s My Waterway,” wish to join an educational session to learn more, and/or desire accompanying curriculum, please email Dana Stephens at dlbigham@ufl.edu.
