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Study: Potentially harmful chemical used in area lakes and ponds

The DNR doesn't put the toxin directly into Clear Lake, but they have spread it in Ventura Marsh, which is attached to Clear Lake.

Posted: Jul 18, 2018 10:15 PM
Updated: Jul 19, 2018 6:43 AM

CLEAR LAKE, Iowa- Dave Howlett and his granddaughter, Brandy, are two of thousands of people who swim in Clear Lake every year.
“It’s kind of like our home away from home,” he said.
But a study done by the Environmental Health Perspective shows that a compound know as rotenone can lead to developing the central nervous system disease, Parkinson’s.
“I never heard of that,” said Howlett.
We reached out to the Iowa DNR Wednesday. They said rotenone is commonly used to kill invasive species in area lakes and ponds as well as manage fish and improve water quality.
They don’t put the toxin directly into Clear Lake, but they have spread it in Ventura Marsh, which is attached to Clear Lake. If you are still wondering what exactly rotenone is, the Iowa DNR describes it as a naturally occurring compound that is derived from the roots of a tropical plant in the bean family. The study was done on farmers who use the chemical on their crops and those with the DNR said the spray they use us only 5% Rotenone. They said in small amounts it shouldn’t have any impact on those swimming like Howlett and Brandy, which is a good thing because they plan to continue regardless.
“I want to enjoy my time out here,” he said. “There are a lot of things that can be bad for your health, but with a little moderation and being wise, you can still have fun.”
The complete statement from the Iowa DNR is below:
"One part of lake restoration projects is to remove all undesirable fish species that have detrimental impacts to the aquatic vegetation, fishery, and water quality. It's imperative that successful removal of these fish species occurs in order to achieve water quality and public recreation goals with these projects, prior to refilling the lake.
Rotenone, a botanical pesticide, is the only management tool that has been proven to remove all of the fish from a waterbody or stream. It is used world-wide and has been since the 1930s. It is a common tool for fish managers when managing sport fish, improving water quality, or for endangered species management. Rotenone is a naturally occurring compound that is derived from the roots of a tropical plant in the bean family. We commonly use the commercially available formulation, 5% Prenfish, which has been approved for fishery management by the U.S. Environmental Protection Agency (EPA). The EPA has concluded that the “use of rotenone for fish control does not present a risk of unreasonable adverse effects to humans or the environment”. The EPA certifies all pesticides based on use according to label directions and the Iowa DNR is equipped to fulfill these obligations. Without this very necessary step in the lake restoration process, much of the benefit to water quality and angling will not be realized.

The DNR and other agencies meet with stakeholders during public meetings explaining the project and use of Rotenone, prior to the project beginning.
Regarding alternatives, we use alternatives when we can, such as fish removal (capture) and alternative methods such as dewatering. At this time, we are not considering scaling back the use of Rotenone."

Typically the DNR spends on average between $50,000-$100,000 annually on Rotenone.

Minnesota Coronavirus Cases

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Cases: 441935

Reported Deaths: 5885
CountyCasesDeaths
Hennepin918591461
Ramsey39405729
Dakota32551324
Anoka30638354
Washington19827221
Stearns17686184
St. Louis13453237
Scott1178693
Wright11485101
Olmsted1024870
Sherburne812364
Carver686636
Clay643278
Rice595266
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Blue Earth533833
Crow Wing476573
Otter Tail449860
Chisago446331
Benton414885
Winona383946
Douglas370366
Nobles364646
Mower358026
Goodhue340757
Polk326754
McLeod321644
Morrison308743
Beltrami305746
Lyon298735
Itasca281143
Becker279438
Isanti279440
Carlton276942
Steele26879
Pine263813
Freeborn237219
Todd230029
Nicollet222136
Brown212334
Mille Lacs211645
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Cass203823
Meeker197433
Waseca187515
Martin168226
Wabasha16712
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Fillmore12084
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Rock108511
Sibley10757
Aitkin106633
Watonwan10548
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Pennington95915
Pipestone92522
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Murray8585
Jackson84510
Swift82617
Pope7355
Marshall70115
Stevens6968
Clearwater68114
Lac qui Parle65216
Lake62215
Wilkin6179
Koochiching57910
Lincoln4771
Big Stone4513
Unassigned43568
Grant4247
Norman4218
Mahnomen4077
Kittson36619
Red Lake3154
Traverse2433
Lake of the Woods1741
Cook1130

Iowa Coronavirus Cases

Data is updated nightly.

Cases: 300884

Reported Deaths: 4197
CountyCasesDeaths
Polk44949440
Linn17563269
Scott15228161
Black Hawk13552228
Woodbury12896175
Johnson1191749
Dubuque11229148
Pottawattamie8863112
Dallas874169
Story857433
Webster464768
Cerro Gordo458766
Sioux452451
Clinton445461
Warren430637
Marshall424561
Buena Vista389029
Muscatine382275
Des Moines377340
Plymouth347967
Wapello336796
Jasper315955
Lee310828
Marion298852
Jones268949
Henry262130
Carroll252233
Bremer240048
Crawford227622
Boone214116
Washington213531
Benton207543
Mahaska189936
Jackson189631
Tama184757
Dickinson183225
Delaware171136
Kossuth169241
Clay165319
Wright161724
Fayette157022
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Hamilton156828
Hardin153129
Harrison152961
Winneshiek150819
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Cedar149119
Butler145423
Page143115
Floyd137236
Cherokee137125
Mills135216
Lyon133132
Poweshiek131024
Hancock127924
Allamakee125927
Iowa122122
Calhoun12159
Jefferson118623
Grundy118522
Winnebago117229
Madison11639
Mitchell114634
Louisa113729
Cass111741
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Sac110115
Emmet109931
Appanoose108838
Union107922
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Guthrie102124
Shelby101026
Franklin99818
Unassigned9370
Palo Alto8969
Keokuk84225
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Howard81119
Monroe79918
Pocahontas77211
Clarke7717
Ida73530
Greene6837
Davis68221
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Osceola6349
Monona62316
Taylor5889
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