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Common pesticide linked to possible birth defects in whitetail deer

Common pesticide linked to possible birth defects in whitetail deer

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A new study published by scientists in South Dakota looked at the most widely used family of pesticides (neonicotinoids) and discovered that the chemicals are “likely causing serious birth defects” in whitetail deer. This discovery could mean that these commonly-used, commercial pesticides are also causing “potential…harm to large mammals, including humans,” the South Dakota News Watch (SDNW) reports.

That study entitled “Effects of Neonicotinoid Insecticides on Physiology and Reproductive Characteristics of Captive Female and Fawn White-tailed Deer” was published in the March 2019 edition of the journal Scientific Reports. The results were based upon a study conducted at the South Dakota State University (SDSU), which used captive deer rather than wild deer. Researchers introduced levels of neonicotinoid pesticide to the captive deer in amounts they thought wild deer could come into contact with naturally. 

What they discovered was rather alarming.

“These (neonicotinoids) were deemed to be safe for higher organisms, and the fact that we saw so many diverse impacts on white-tailed deer, that was a big thing,” said Dr. Jonathan Lundgren, an ecologist and an independent scientist who co-authored the study. “And then, the fact that whitetail deer are not that far off from our livestock or even humans suggests that maybe we need to be examining these insecticides’ risks a little bit more closely.”

The study has been called “groundbreaking” and has resulted in another SDSU study currently in-progress that will “examine whether ring-necked pheasants also could be harmed by neonicotinoid pesticides,” according to SDNW. Within the whitetail study, researchers found high levels of the pesticide in the adult deer spleens, causing the animals to develop defects like “smaller reproductive organs, pronounced overbites and declined thyroid function” and fawns that were “generally smaller and less healthy,” SDNW reports

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This type of pesticide has been widely used since the late 1990s for insect control and seed protection. In fact, according to SDNW, it’s even available at a residential level through landscaping treatments like Bayer Advanced Tree and Shrub Insect Control. While the neonicotinoid pesticides haven’t been concretely linked to human health issues, that’s partially due to the fact that scientists are only starting to figure out how to measure the presence of these chemicals in the human population. 

Researchers with the Center for Disease Control and Prevention published a September 2019 paper that showed the prevalence of neonicotinoid pesticides in people: 49.1% of the urine samples collected during the 2015-16 National Health and Nutrition Examination Survey had traces of the chemical, leading the CDC to estimate that about 50% of the U.S. population “had recently been exposed to neonicotinoids,” according to SDNW. Further, another study published in January 2019 entitled “Trends in neonicotinoid pesticide residues in food and water in the United States, 1999-2015”, discovered low levels of the chemicals on “nearly 60% of cauliflower, 45.6% of spinach and 29.5% of the apples” that were sold for humans to eat. 

While more research needs to occur, it is important to pay attention.

“It is potentially having an effect on survival of fawns in a number of different ways that could decrease the number of young available or that get recruited into deer populations,” Dr. Jonathan Jenks, a wildlife ecologist and co-author of the whitetail study.


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Ryan L. - posted 1 month ago on 10-22-2019 03:19:09 pm

Tanner J-

Just wanted to say, although I know next to nothing about what you're talking about here, this is a great comment. Well thought out, not reactionary or defensive, no accusations of nefarious intent, just simply stating your input and (possible) disagreements that you have identified in a healthy and productive way.

Whether this article (or you) is right or wrong, these are the kind of healthy and productive comments that lead to healthy and productive conversations, which at least in theory will lead to healthy and productive solutions.

Well done, sir.

TANNER J. - posted 1 month ago on 10-22-2019 08:31:26 am

I work in the agriculture industry and here is a few brief points to keep in mind:

1. While many of the summaries (in newspapers and social media right now) on the actual study say “neonics”, the research was not on ALL neonics, just imidacloprid.

2. No corn in the United States, that I am aware of, is treated with imidacloprid (Gaucho). It is all treated with either Poncho or Cruiser. Not saying that there couldn't be any.

3. The most widespread use of imidacloprid at the highest rates is in turf & commercial applications, think golf courses & lawns, where the product is applied multiple times per year ON THE SOIL SURFACE. While the researchers “don’t know” where the imidacloprid is coming from, you can simply look at the use across the country and figure out where it most likely has been applied.

4. For years, we have been encouraging farmers to NOT USE NEONICS post-emerge on crops, in order to prevent bee kills. Bee kills are NOT coming from seed treatment usage, so let’s limit applications to just seed treatment. It appears the same may be true for this deer study.

5. It will be very interesting to see what the EPA and other chemical companies have to say about this study. More importantly, I think bigger studies need to be done to gain more data because when it comes to birth defects in deer, that’s been happening for decades, and well before imidacloprid use was present. I’m not saying their study is wrong, but I want to see more data before we pass judgment on imidacloprid.