It's a complicated question to which the Ocean Research & Conservation Association One Health Indian River Lagoon Fish Monitoring project is seeking answers through this citizen science project. Volunteers are trained to carefully remove certain parts of fish and prepare samples for scientific research.
ORCA scientists study those gills, livers, stomachs and fillets to understand the pollutants that are in fish that people eat from the Indian River Lagoon and its tributaries in Martin, St. Lucie, Indian River and Brevard counties. They're identifying what pollutants are in what parts of the body and in what concentrations.
Are Indian River Lagoon fish safe to eat? Preliminary results have found:
Microplastics
Cyanotoxins, such as microcystin and saxotoxin found in blue-green algae blooms
Heavy metals such as mercury, lead and cadmium
Glyphosate, the active ingredient RoundUp herbicide.
All those pollutants are harmful to people, and some were found in concentrations that exceed the Environmental Protection Agency's recommended consumption levels. Some toxins are manmade, such as glyphosate, and some occur naturally, such as microcystin.
"We're concerned with the two parameters which were more elevated, but for different reasons: Mercury in the fillets and glyphosate because there are no standards for safe consumption levels," says Missy Weiss, director of ORCA's citizen science program. The microcystin, she says is not of the same concern because it is more related to time and location.
Mercury in fish
99% of 832 fish tested had mercury
In Martin County, more fish had higher concentrations than any other county.
Bluefish and spotted seatrout concentrations exceeded the EPA level for the general population
Nine fish species had concentrations that exceeded the EPA level for children and pregnant people: whiting, bluefish, pompano, flounder, sheepshead, spotted seatrout, mangrove snapper, Spanish mackerel, red drum (redfish)
Black drum concentrations were lower than EPA limits for children and pregnant people.
Glyphosate in fish
100% of 116 fish tested had glyphosate
Glyphosate can persist in the environment for 47 to 315 days
The EPA has recommendations for glyphosate in drinking water, but not consumption in fish.
Microcystin in fish
43% of 667 tested fish had microcystin
Its presence decreased dramatically in samples from 2020 to 2022
Concentrations ranged from 0 to 3.16 parts per billion
The EPA has recommendations for microcystin in drinking water, but not consumption in fish.
Microplastics in fish
57% of 488 tested fish had microplastics
77% of 39 fish fillets had microplastics
Stomach concentrations ranged from 0 to 21 pieces of plastic
Most people do not eat the stomachs.
ORCA hopes to expand the project to include PFAS, parasites, pharmaceuticals and controlled substances.
"The research shows which specific pollutants are accumulating in the aquatic food chain that may be transferred to humans and other animals that eat fish," Weiss said. "We anticipate building relationships with health departments and health care providers to share critical information resulting from this project."
Scientists have examined about 1,000 fish from 30 different saltwater and freshwater species, Weiss said.
The project's three main goals are to:
Understand the pollutants and concentrations found in consumed fish
Provide fish consumers the information they need to protect themselves from exposure to toxins
Provide water managers, health departments and policymakers with science-based information to make rules governing fish consumption.
The project also involves surveys of recreational anglers to understand which species of fish and which parts of the fish people regularly eat. Preliminary results about the respondents show:
83% eat just the fillet, 13% eat the skin too
82% are year-round residents
84% male, 14% female (2% unidentified)
54% ages 18-64 and 35% ages 65 and older
There are three ways people can help with the ongoing project.
Go Fishing For Science!
Local anglers can do their part to monitor this important ongoing research. After all, fishing is a way of life for so may in our area and ORCA wants to monitor the safety of the fish you may consume from our Indian River Lagoon! Anglers are key to this effort and ORCA would like your help.
The target species for ORCA's One Health Fish Monitoring project currently include spotted seatrout, black drum, mangrove snapper, sheepshead, mackerel, bluefish, mullet, flounder, pompano, hardhead catfish, whiting, snook, red drum, spotted seatrout, spanish mackerel, armored catfish, mayan cichlid, tilapia, crappie, and channel catfish.
How to donate fish for ORCA research
Keep fish whole and on ice
Must be legal and in-season
Label with date, time caught and GPS location
Fish should be from Indian River Lagoon and connecting waterways; not the ocean
Take fish to a drop-off location
Questions? Email fish@teamorca.org