Return to the Roses Forum | Post a Follow-Up

 o
precautionary principle and tebuconazole

Posted by henry_kuska z5 OH (kuska@neo.rr.com) on
Wed, Jun 16, 10 at 22:26

If you are interested in what current research is reporting concerning tebuconazole, the following abstract may be of interest:

Title: Combined exposure to endocrine disrupting pesticides impairs parturition, causes pup mortality and affects sexual differentiation in rats

Authors: P. R. Jacobsen, S. Christiansen, J. Boberg, C. Nellemann and U. Hass

Authors affiliation: Department of Toxicology and Risk Assessment, National Food Institute, Technical University of Denmark, Sborg, Denmark

Published in: International Journal of Andrology, volume 33, pages 434442, (2010).

ABSTRACT: "Risk assessment is currently based on the no observed adverse effect levels (NOAELs) for single compounds. Humans are exposed to a mixture of chemicals and recent studies in our laboratory have shown that combined exposure to endocrine disrupters can cause adverse effects on male sexual development, even though the doses of the single compounds are below their individual NOAELs for anti-androgenic effects. Consequently, we have initiated a large project where the purpose is to study mixture effects of endocrine disrupting pesticides at low doses. In the initial range-finding mixture studies, rats were gavaged during gestation and lactation with five doses of a mixture of the fungicides procymidone, mancozeb, epoxyconazole, tebuconazole and prochloraz. The mixture ratio was chosen according to the doses of each individual pesticide that produced no observable effects on pregnancy length and pup survival in our laboratory and the dose levels used ranged from 25 to 100% of this mixture. All dose levels caused increased gestation length and dose levels above 25% caused impaired parturition leading to markedly decreased number of live born offspring and high pup perinatal mortality. The sexual differentiation of the pups was affected at 25% and higher as anogenital distance was affected in both male and female offspring at birth and the male offspring exhibited malformations of the genital tubercle, increased nipple retention, and decreased prostate and epididymis weights at pup day 13. The results show that doses of endocrine disrupting pesticides, which appear to induce no effects on gestation length, parturition and pup mortality when judged on their own, induced marked adverse effects on these endpoints in concert with other pesticides. In addition, the sexual differentiation of the offspring was affected. This as well as the predictability of the combination effects based on dose-additivity modelling will be studied further in a large dose-response study."


Follow-Up Postings:

 o
RE: precautionary principle and tebuconazole

"five doses of a mixture of the fungicides procymidone, mancozeb, epoxyconazole, tebuconazole and prochloraz."

This leads me to conclude that the study cannot pinpoint which fungicide caused the end results, since it was a MIXTURE and not just tebuconazole as your heading suggests.


 o
RE: precautionary principle and tebuconazole

Tebuconazole was there but in a concentration BELOW its "no observable effects" concentration (the same with the others). The point of the research is that one cannot test chemicals separately and be confident that it is not harmful when mixed with other chemicals.

The first part of the INTRODUCTION SECTION of the full paper may be of interest:

"Animal laboratory experiments have shown that in utero
exposure to endocrine disrupting chemicals (EDCs)
including some pesticides can cause adverse effects on
male reproductive development (Foster, 2006; Gray et al.,
2006; Hass et al., 2007; Metzdorff et al., 2007; Christiansen et al., 2008). Individual pesticides alone have so far not been shown to contribute to adverse human effects at relevant exposure levels. However, some studies indicate increased prevalence of cryptorchidism and decreased penile length in sons of women working as gardeners or Many EDCs have been found as mixtures in humans
(Blount et al., 2000; Swan et al., 2005), including children
(Brock et al., 2002; Swan et al., 2005; Main et al., 2006).
Damgaard et al. (2006) observed an association between
congenital cryptorchidism and the levels of certain
organochlorine pesticides in mothers milk (Damgaard
et al., 2006). Earlier, Pierik et al. (2004) identified paternal exposures to pesticides and smoking as factors associated with these congenital malformations. These initial observations in epidemiological studies points in the same direction as laboratory experiments with oestrogenic or anti-androgenic chemicals in which substantial mixture effects occurred even though each individual chemical was present at low, ineffective doses (Rajapakse et al., 2002; Silva et al., 2002; Hass et al., 2007; Metzdorff et al., 2007; Christiansen et al., 2008, 2009).
Some pesticides such as vinclozolin and procymidone
antagonize competitively the androgen receptor (AR)
binding of androgens and affect mainly the reproductive
development in male offspring (Kelce et al., 1997; Ostby
et al., 1999). Other pesticides such as mancozeb and propineb act mainly via disruption of the thyroid hormones and are mainly suspected to disrupt brain development (Hurley, 1998; Hass & Axelstad, Personal Communication).
Our detailed research on prochloraz, combined with
studies on other azole fungicides such as tebuconazole
and epoxyconazole, indicates that these pesticides have
the ability to react through several endocrine disrupting
mechanisms, and to induce various endocrine disrupting
effects (Vinggaard et al., 2005a,b; Taxvig et al., 2007). We
have shown that prochloraz induced anti-androgenic
effects in rats in vivo in a Hershberger test as well as in a developmental toxicity study (Vinggaard et al., 2002, 2005a). In addition, our studies show that prochloraz
increases gestation length and indicate that prochloraz
may also affect thyroid hormone levels and cause effects
on the sexually dimorphic development of the brain
(Vinggaard et al., 2002, 2005a). Both tebuconazole and
epoxyconazole increase gestation length and pup
mortality and furthermore, these pesticides virilise female
pups, and affect steroid hormone levels in foetuses and ⁄ or
dams (Taxvig et al., 2007)."


 o
RE: precautionary principle and tebuconazole

Sometimes the full complete scientific paper is available free to the public. The Taxvig et al., 2007 paper referenced in the last sentence of my last post is one of those that is available:

http://toxsci.oxfordjournals.org/cgi/content/full/100/2/464

Here is a link that might be useful: link for above.


 o
RE: precautionary principle and tebuconazole

The final sentence of the full paper (Taxvig et al., 2007) is: "Thus, it seems important to survey and minimize the exposure of the human population to azole fungicides."

----------------------------

I feel that it is important to point out that this was NOT written in a "save the spotted whale" type web page but in a reviewed scientific journal published by Oxford University Press (in 2008 the journal was ranked 5 out of 75 journals in toxicology, see http://www.oxfordjournals.org/our_journals/toxsci/about.html ).

That statement ("Thus, it seems important to survey and minimize the exposure of the human population to azole fungicides.") had to be be approved by the outside scientific reviewers and the journal editor.

Even though the statement is somewhat softened by the use of "seems important", I feel that it is an unusually strong statement for a scientific journal publication.


 o
RE: precautionary principle and tebuconazole

Eureopean Union action.
"Permits for 22 substances known to cause cancer, harm human reproduction or damage the hormonal system will not be renewed under the new law. Exceptions will be made only for cases where there is no alternative product, or where the harvest is seriously threatened as a result of the ban.

Most of the pesticides concerned are produced by German chemical industry giants Bayer or BASF, and include Amitrol, Ioxynil, Tepraloxydim, Epoxiconazole, Iprodion, Metconazole, Tebuconazole and Thiacloprid."

See:

http://www.digitaljournal.com/article/265134

Here is a link that might be useful: link for above


 o
RE: precautionary principle and tebuconazole

  • Posted by jim1961 z 5/6 central pa (My Page) on
    Fri, Jun 18, 10 at 11:39

There is a very fine line here. Most of us would love to see the rose industry flourish for many years to come.
I'm afraid if they banned all chemical fungicides in the USA the rose industry would crumble into dry dust.
I agree that chemicals may be bad for our health and for the health of the environment.
But, I think we are between a rock & a hard place with this subject.


 o
RE: precautionary principle and tebuconazole

jim1961 maybe someone here will tell us how rose growing is doing in Ontario.


 o
RE: precautionary principle and tebuconazole

The Taxvig article says tha the pups were divided into groups and given tebuconazole "by gavage". That means they stick a tube down it's throat and force it to drink it. It said the dosage was 0, 50, and 100 mg/kg. That calculates out to 3.4 grams of pure substance for a 150 lb person for the 50 mg/kg. Obviously the 100 mg dosage is twice that. They were dosed that amount for 10 days in a row. 3.4 and 6.8 mg is a lot to just consume. Without knowing whether is compound is light and puffy or more dense and crystalline, I can't say whether it would be closer to a tablespoon or a teaspoon. Either way, that amount was given for 10 days in a row. One wonders how that compares to the lifetime exposure to a rosarian who is only in proximity to the diluted compound we work with, and just spraying it....


 o
RE: precautionary principle and tebuconazole

Thank you, ARoselady, for breaking the data down into understandable language...


 o
RE: precautionary principle and tebuconazole

arkroselady, your question: "One wonders how that compares to the lifetime exposure to a rosarian who is only in proximity to the diluted compound we work with, and just spraying it...."

seems to be indicating (to me, H. Kuska) that you are thinking along the lines of a classical concentration dependent poison..... that if the amount is small, the body will cleanse itself of the chemical and return to normal. The authors comment on that line of thinking:

"Small effects on hormone levels might be without clinical effects in adults because of a tightly controlled homeostasis (H. Kuska comment...see http://en.wikipedia.org/wiki/Human_homeostasis ) but could have detrimental effects if they occur under vulnerable stages of reproductive development in the fetus (Sharpe, 2006; Toppari et al., 2006). Although the endocrine-disrupting potency for the individual triazole compounds seems rather low compared to the concentrations of these compounds in the environment and diet, human exposure to several azole fungicides simultaneously is likely, due to the wide use of these compounds, and since the azole fungicides share several mechanisms of action and endpoints (Birkhj, M., Taxvig, C., Vinggaard, A.M., and Andersen, H.R.), the combined effects induced by these fungicides might be additive. Likewise, they can also add to effects induced by other environmental EDs sharing similar mechanisms (Birkhj et al., 2004; Rajapakse et al., 2002; Silva et al., 2002). Thus, it seems important to survey and minimize the exposure of the human population to azole fungicides."
---------------------------------------------
Another point. What you spray does not just disappear. It becomes part of the chemical load on out planet.

The following 2 papers discuss what happens to the tebuconazole after it is sprayed i.e. does it get into the water system and can we remove it:

"Loads determined in untreated and treated wastewater indicated that fluconazole, propiconazole, and tebuconazole were largely unaffected by wastewater treatment"

See:

http://pubs.acs.org/doi/abs/10.1021/es8009309

AND

"The findings demonstrate that significant levels of fungicides enter river waterways and that only some of these compounds are being reduced in low levels by municipal wastewater treatment processes"

See:

This link is too long to list. See "Optional Link URL" below

Here is a link that might be useful: 2nd link that was too long to list


 o
RE: precautionary principle and tebuconazole

arkroselady, that is similar to the NY State EPA that banned the Bayer based on a person using 30 gallons of the diluted formula A DAY. Their previous report was on 100 gallons a day. Now who would be spraying 30 gallons a day? Certainly not the average rose grower.

People who do this for a living might have an issue with the chemicals. But I would assume they were protective gear when spraying.


 o
RE: precautionary principle and tebuconazole

The link below gives the actual New York ban letter:

"CONCLUSION: The toxicological properties of tebuconazole (especially those that would potentially impact reproduction and development), the low MOEs (below 1,000) for some exposures, the relatively large product package size/quantity, and the frequency of some recommended applications, raise concerns for use of Bayer Advanced Garden Disease Control Concentrate by homeowners. When used as labeled, this product could cause unreasonable adverse effects to humans. The Department hereby denies the application to register Bayer Advanced Garden Disease Control for Roses, Flowers, and Shrubs Concentrate (EPA Reg. No. 72155-14)."

-------------------------------

Concerning quantities, please note the "could pose storage and disposal issues." in the quote in context:

"The Bayer Advanced product as labeled also raises several concerns given that it is intended for homeowner use. The product contains 32 fluid ounces of concentrate that makes up to 42 gallons of diluted spray. These are substantial quantities for a homeowner product and could pose storage and disposal issues. In addition, the frequency of application in some cases (i.e., for protection of flowers) is as much as two to three times per week, thus creating considerable exposure potential from mixing, loading and application especially if the homeowner does not adhere to the label directions for wearing protective clothing and rubber gloves."

Here is a link that might be useful: New York ban letter


 o
RE: 2 nd New York denial, precautionary principle and tebuconazol

The following link gives another New York denial letter 2 years later (in 2007):

"Registration Summary:
The Department continues to have reservations regarding the registration of homeowner products which contain the active ingredient tebuconazole. Bayer Advanced, LLC has failed to demonstrate a compelling need for these products/active ingredient in the homeowner marketplace. There are several fungicide products already on the market and the tebuconazole concentrates do not demonstrate a safer alternative to other formulations that contain either chlorothalonil, triforine, myclobutanil or propiconazole. Tebuconazole is a possible carcinogen and is mobile in sandy loam soils such as found in areas of New York State. The relatively large product package size/quantity, and the frequency of some recommended applications raise concerns for use of Bayer Advanced Garden Disease Control Concentrate by homeowners. When used as labeled, this product may cause unreasonable adverse effects to human health and the environment. Additionally, the dual action products (fungicide and insecticide) may lead to unnecessary applications of either the insecticide or fungicide when only one control measure may be needed."

http://pmep.cce.cornell.edu/profiles/fung-nemat/tcmtb-ziram/tebuconazole/tebucon_den_0107.pdf

Here is a link that might be useful: Second N.Y. denial


 o
RE: precautionary principle and tebuconazole

" These are substantial quantities for a homeowner product and could pose storage and disposal issues. In addition, the frequency of application in some cases (i.e., for protection of flowers) is as much as two to three times per week, thus creating considerable exposure potential from mixing, loading and application especially if the homeowner does not adhere to the label directions for wearing protective clothing and rubber gloves."

Ridiculous. The Bayer is meant to be applied once every 2 weeks. Maybe once a week if you have an active blackspot infestation. Which you will not get if you use it every 2 weeks. You can even skip to 3 weeks in the hot summer months. The label recommends every 7-14 days. There is a 2-3 day application for petal blight on shrubs (not roses) but that would only be for a short period.

Any chemical can be dangerous if you don't follow the labels or use proper protection. Most household chemicals can cause problems and they aren't banned. Going on about the size of the bottle seems a bit silly. There are other products that come in a concentrated form, are they also banned?

As far as their being 'other fungicides' that people can use, well none work as well as the Bayer. It sounds to me like Bayer is getting the shake down from NY State. I guess they forgot to pay somebody in that whacky state legislature off.

Wait, I just saw this:

"The relatively large product package size/quantity, and the frequency of some recommended applications raise concerns for use of Bayer Advanced Garden Disease Control Concentrate by homeowners. When used as labeled, this product may cause unreasonable adverse effects to human health and the environment. Additionally, the dual action products (fungicide and insecticide) may lead to unnecessary applications of either the insecticide or fungicide when only one control measure may be needed."

The disease control DOES NOT include insecticide!!!! Either the people in the NY State EPA can't read or they are incredibly stupid. I can excuse a consumer in a store from misreading labels and getting confused on a product, but not someone who is doing a scientific study and is going to have the power to ban a product.

If anything, this letter has convinced me that when used properly, the Bayer is safe to use.


 o
RE: precautionary principle and tebuconazole

Here is the Bayer label if anyone is interested:

Bayer Label

My problem isn't with anyone here. It's with NY State. I lived there for my entire life and am so glad I moved out. That state is a mess.


 o
RE: precautionary principle and tebuconazole

Buford thank you for posting the label link to one of the three products that New York discussed in the 2007 letter.

You seem to have missed that the 2007 letter discussed three different Bayer products.


 o
RE: precautionary principle and tebuconazole

The link below is to a 2009 letter from New York State to a company concerning the registration of their product containing tebuconazole (the company withdrew their application).

Please notice particularly the following: "Based on these data, the USEPA classified tetraconazole as "likely to be carcinogenic to humans.""

The cancer ratings are explained at:

http://www.epa.gov/opp00001/health/cancerfs.htm#a

Here is a link that might be useful: 2009 letter


 o
RE: precautionary principle and tebuconazole

Well the quote here is specifically about the Bayer Advanced Disease Control:

"The relatively large product package size/quantity, and the frequency of some recommended applications raise concerns for use of Bayer Advanced Garden Disease Control Concentrate by homeowners. When used as labeled, this product may cause unreasonable adverse effects to human health and the environment. Additionally, the dual action products (fungicide and insecticide) may lead to unnecessary applications of either the insecticide or fungicide when only one control measure may be needed."


 o
RE: precautionary principle and tebuconazole

One moderate conclusion to be drawn is that it is foolish to tank-mix two fungicides if one alone will do the job.


 o
RE: precautionary principle and tebuconazole

I can only think that they were referring to the drench product that combines fungicide and insecticide. And I agree that it's over kill to use that weekly or even every other week. But I do believe that product (the 3 in 1) says to use every 6 weeks or so. I no longer use it because I don't see the need for a systematic insecticide.


 o
RE: precautionary principle and tebuconazole

The three products (discussed in the 2007 letter) were:

"1. Bayer Advanced Garden Disease Control for Roses, Flowers & Shrubs Concentrate (EPA Reg. No. 72155-14) contains 2.9% tebuconazole; 1 quart of concentrate makes 42 gallons of use solution for foliar treatment.

2. Bayer Advanced All-in-One Rose & Flower Care Concentrate (EPA Reg. No. 72155-21) contains 0.8% tebuconazole and 0.15% imidacloprid; 1 quart of concentrate makes between 4 gallons of use solution for drench treatment of rose bushes and 32 gallons of use solution for flower beds.

3. Bayer Advanced Dual Protection ACR Insect & Disease Control Concentrate (EPA Reg. No. 72155-61) contains 1.0% tebuconazole and 0.2% imidacloprid; and 1 quart of concentrate makes between 4 gallons of use solution for drench treatment of selected shrubs and 32 gallons of use solution for flower beds."

When they said: "Additionally, the dual action products (fungicide and insecticide) may lead to unnecessary applications of either the insecticide or fungicide when only one control measure may be needed." they were referring to product 2) and product 3).


 o
RE: precautionary principle and tebuconazole

I goofed, the 2009 letter from New York is for a fungicide containing tetraconazole NOT tebuconazole. please disregard that post.

Sorry.


 o
RE: precautionary principle and tebuconazole

Interesting information. I'll put a link below to the brief description on Wikipedia:

Here is a link that might be useful: Tebuconazole


 o
RE: precautionary principle and tebuconazole

A just announced British report states:

"The names of chemicals (including pesticides) known or suspected to have endocrine disrupting properties can also be found in reports on the European Commissions website.iii The EC now has a list of around 200 substances which show clear evidence of endocrine disrupting effects. Given the possibility of additive effects from simultaneous exposure to several hormone disrupting chemicals, any exposure even to low levels of a particular hormone disrupting pesticide might be expected to potentially contribute to an effect. Therefore, it would be wise to ensure the EU legislation is strictly implemented in order to try to eliminate exposure to hormonally active pesticides."

The full report is given in the link box. A press release summary is at:

http://www.externalrelations.stir.ac.uk/news/news_stories/index.php

Here is a link that might be useful: Full British report


 o
RE: precautionary principle and tebuconazole

General very recent article about the problem, "Hormone-disrupting chemicals a danger to all".

"As legitimate as these debt fears are, the Utah Physicians for a Healthy Environment have been concerned that future generations are facing a "chromosome debt" that may pose an even greater threat to their health and quality of life. To the extent we contaminate our environment, we contaminate the very building blocks of life itself. A special investigative report last month by CNN has finally given a nationwide voice to these concerns."

Here is a link that might be useful: link for above


 o
RE: precautionary principle and tebuconazole

Thank you, Henry, for pulling all this together and doing so much research.

All of these chemicals--herbicides, fungicides, pesticides--are, as the last syllable translates, killers. They are meant to disrupt the natural system of checks and balances in favor of human preference. They are short-term solutions to conditions perceived as problems by only one species. They introduce and accumulate changes which may not be immediately perceived but nevertheless do alter the system. All life forms share a basic biochemistry and if a chemical can kill one life form, you can bet that, in sufficient doses, it will kill most others. Your use today may not kill you, but your use and your neighbors' may produce some really funny looking grandchildren.

Think of it as putting sugar in your gas tank. A spoonful here or there isn't noticeable. But eventually, the sugar will accumulate and the car won't run.

This is common sense, basic logic, even old homily: what you put in is what you get out.


 o
RE: precautionary principle and tebuconazole

Catsrose's observations re common sense, basic logic, selfish human preferences and the ultimate impact on grandchildren are well taken.

But isn't it interesting how we all pick our favorite poisons, embrace them with a vengeance, and become incensed when anyone questions our use of them? Would rational creatures truly concerned about grandchildren, healthy environments and the future of life in general be able to view today's Gulf of Mexico and still be hell-bent on drilling as many off-shore wells as we possibly can as fast as we can?


 o
RE: precautionary principle and tebuconazole

If we grow plants that are suitable to our zone, and if we learn to appreciate what we have, we don't need so many chemicals, if any. I have not sprayed for a number of years, and my roses are beautiful. When I took them to the State Fair last year, they were considered inferior, and some people gave me suggestions on how to prop them up, or how to do other things. Those people had no knowledge of the Antique roses. However, if you grow them, they are easy to love.

I no longer desire the huge red pure rose with large clean leaves. I like what grows here. I would love to go to a local nursery with flowers grown locally, and buy a bouquet. It seems that our goals anymore are to get what is the rage and create circumstances that will make them grow locally.

We need to use chemicals often, but not always. I would not skip termite treatment, and I am glad that there are ant baits because ants could overrun the world. But my roses are very pretty, and they don't need spray.

What I dislike the most about these chemicals is the process of trying to decide if they are safe. It is just like so many pharmaceuticals (hormones for example). "OOPS, sorry women, this can cause heart disease instead of prevent it! So sorry!"

Henry, I appreciate your introducing these papers from time to time. My point is that the proof should come before the sales.

I could say more, but will stop now. I'm sorry that this is so long.

Sammy


 o Post a Follow-Up

Please Note: Only registered members are able to post messages to this forum.

    If you are a member, please log in.

    If you aren't yet a member, join now!


Return to the Roses Forum

Information about Posting

  • You must be logged in to post a message. Once you are logged in, a posting window will appear at the bottom of the messages. If you are not a member, please register for an account.
  • Posting is a two-step process. Once you have composed your message, you will be taken to the preview page. You will then have a chance to review your post, make changes and upload photos.
  • After posting your message, you may need to refresh the forum page in order to see it.
  • Before posting copyrighted material, please read about Copyright and Fair Use.
  • We have a strict no-advertising policy!
  • If you would like to practice posting or uploading photos, please visit our Test forum.
  • If you need assistance, please Contact Us and we will be happy to help.


Learn more about in-text links on this page here