In 2017, the Iowa Department of Natural Resources reported to the U.S. Environmental Protection its findings from the prior two-year cycle that nearly half of the state’s bodies of water had some sort of impairment.
All told, Iowa had 750 lakes, rivers and streams that failed to meet water quality standards for an intended use — drinking, recreation or supporting aquatic life. Although that was a slight improvement from the previous report in 2015, it didn’t tell the whole story.
Because of budget cuts, not all bodies of water were tested — 52 percent of rivers, 61 percent of lakes and reservoirs and 83 percent of wetlands. In 2016, Saylorville Lake north of Des Moines was considered unimpaired — until warnings on the beach were posted that summer because of toxic algal blooms.
So what about the fish in those waterways, are they safe to consume?
A joint project by staffers at Cedar Falls High’s Tiger Hi-Line, the nonprofit IowaWatch.org (the Iowa Center for Public Affairs Journalism) and the University of Northern Iowa’s journalism department determined the answer is yes, albeit a bit murky in Iowa and surrounding states as well.
Fishing is big business. The DNR took in $8 million from fishing licenses in 2018. Fishing locations, hot spots and tips are prominent on its website. Not as readily available, but still accessible, are its warnings.
Suffice it to say, fish are part of a healthy diet with the proper preparation. However, the quantity of fish consumed may well be determined by the species and where it’s caught (excluding private ponds, which the DNR doesn’t monitor).
The DNR advises anglers to limit consumption of fish caught in 22 Iowa lakes and rivers because of contaminants like mercury and PCB (polychlorinated biphenyls), a highly toxic industrial compound that can pose serious developmental and neurological risks to fetuses, babies and children after repeated exposure to small amounts.
Because you can’t see, smell or taste either of those contaminants, it’s best to take some precautionary measures by accessing the DNR’s “Fish Consumption Advisories” based on fish tissue samples at www.iowadnr.gov/Environmental-Protection/Water-Quality/Water-Monitoring/Fish-Tissue. (The DNR’s goal is to take fish-tissue samples from popular fishing sites every 10 years and key river segments every five years.)
For instance, in the Cedar River along U.S. 218 from Floyd to the Minnesota state line and the Iowa River from below the Iowa Falls dam to Coralville, the DNR warns against eating more than one meal per week of any predator fish (walleyes, northern pike, lake trout) because of mercury contamination.
No matter the catch, though, trim the skin and fat, particularly belly fat. In fatty fish such as carp, catfish and lake trout, PCBs tend to accumulate. By all means, clean and cook properly.
You have free articles remaining.
Unfortunately, the 2018 Iowa Angler Survey of 1,628 fishermen and women conducted by Responsive Management of Harrisonburg, Va., for the DNR, found that the vast majority of respondents were either unaware of or didn’t heed the warnings:
- 84 percent think Iowa’s fish are safe for eating.
- 28 percent think Iowa’s water quality is better than a decade ago; 31 believe it’s worse.
- 80 percent consumed some of the fish caught, while 78 percent didn’t limit consumption — a total of 4.6 million meals of Iowa-caught fish.
The Tiger Hi-Line and IowaWatch.org report found that monitoring in surrounding states is far from comprehensive:
- South Dakota tested 14 water bodies last year.
- Nebraska annually tests approximately 40-50 pre-selected streams and publicly owned lakes in two or three of its 13 major river basins.
- Illinois tests 40-50 streams, rivers and inland lakes and four Lake Michigan open-water stations annually.
- Wisconsin collects fish from approximately 50 to 100 sites annually.
- Minnesota tests fish samples from approximately 130 lakes and river segments annually.
And standards vary.
Iowa advises that a healthy fish portion is equivalent to a happy-hour special — 6 ounces. In Nebraska, it’s a more realistic 8 ounces.
Using new science standards, Minnesota recently changed its risk assessment for fish contaminated by perfluorooctane sulfonate — chemicals present in non-stick cookware, food packaging, waterproof clothing, fabric stain protectors, lubricants, paints, and firefighting foams — from 800 ng/g (nanograms per gram) to 200 ng/g.
PFOS are linked to immunotoxicity, decreased sperm count, low birth weight and thyroid disease, primarily from fish consumption. Eating fish accounts for 90 percent of human exposure to PFOS.
IowaWatch.org notes “Iowa’s safety advisories offer stricter consumption guidelines than those placed on fish purchased from grocery stores and restaurants.”
Still, as the Tiger Hi-Line and IowaWatch.org report makes clear, it’s advisable to take personal responsibility for your health and well being when catching and consuming fish.
Access the aforementioned DNR website and learn about possible contamination before casting your line.