Fiesta Kills Fish?

Discussion in 'Organic Lawn Care' started by ecoguy, Feb 6, 2014.

  1. ecoguy

    ecoguy LawnSite Member
    from Duncan
    Posts: 234

    Thanks very much for this! Yes, I did have the sheet and also knew this info (although not as well as I do now) which is why I was so confused by the customer's claim. Our spray was minimal. Will be interested to hear what the manufacturer's say. Thanks again for this Rlitman. Great work.
  2. ecoguy

    ecoguy LawnSite Member
    from Duncan
    Posts: 234

    Hey all. Just received this official response from the Neudorff, the Fiesta Manufacturer.

    It’s unfortunate that this customer lost his fish; however, it is very unlikely that it was related to the Fiesta application. In this scenario Fiesta wouldn’t have reached the pond, and even if it did, FeHEDTA is not toxic to fish.

    1. Fiesta is diluted 1 in 25 prior to use, which means that the bulk of the end-use product is water.

    2. Fiesta was applied 5-6 feet from the pond. Nearly all of the FeHEDTA applied is immediately absorbed by the grass and weeds and doesn’t reach the soil layer. The FeHEDTA is then degraded by light and/or metabolized by the grass within a day or two. It has a very low potential for leaching (does not travel through soil to runoff into water.)

    3. Even if it did somehow reach the water, FeHEDTA is soluble in water and is rapidly degraded by natural light.

    4. The regulatory authorities do consider the potential impact to fish and aquatic organisms when evaluating a pesticide. I’ll attached the Canada and US evaluations.

    From the Canada PRD: “FeHEDTA is expected to pose negligible risk to terrestrial and aquatic organisms under conditions of use for application to turf.” The toxicological studies found no toxicity at the highest concentration tested for fish (rainbow trout) and aquatic invertebrates (Daphnia).

    From the EPA BRAD: “Studies indicate that iron HEDTA will not cause adverse effects to mammals, birds, fish and aquatic invertebrates, other non-target insects, or plants.” The toxicological studies concluded that iron HEDTA is “practically non-toxic”, which is the safest EPA level of classification, to fish or aquatic invertebrates.

    Let me know if you have any more questions.

  3. rlitman

    rlitman LawnSite Bronze Member
    Posts: 1,552

    My numbers were based on Fiesta concentrate. I did not look up mixing directions because as I discovered, the concentrate itself is not particularly harmful. So just multiply those numbers by 25 for the final mixed product (i.e. it would take 25x as much to cause damage).

    Also, from the sounds of the response, they're using EDTA, not necessarily NTA as the chelating agent. Off the top of my head, EDTA is much less toxic than NTA, and with NTA being the worst component, it sounds like it is actually far safer than I assumed.

    So yeah "your customer is full of crap". But at least you now have an official response from the manufacturer so you can break it to them lightly. :)
  4. RigglePLC

    RigglePLC LawnSite Fanatic
    Posts: 12,233

    The customer is always right in this situation. Do NOT yourself claim that it is not possible, say you don't know. DO show him the manufacturers response. Ask the customer what he wants you to do. Compensate the customer in some way--say a free ap next year. Its a cost of doing business. If you handle this right, professionally, he will give you referrals, if not, he will tell all his friends that you are incompetent.

    Actually you are right--it is highly unlikely. Fish die all the time, too many fish for the size tank, warm water conditions, low oxygen, disease, and sprays of pyrithroid products (as pointed out above). Why would the water get clear? Hmmm...maybe they used an algicide...and it killed the fish. Swimming pool algicides probably do not belong here.
  5. RigglePLC

    RigglePLC LawnSite Fanatic
    Posts: 12,233

    Whoops sorry double post.
  6. phasthound

    phasthound LawnSite Platinum Member
    Posts: 4,584

    The EPA/PMRA screening level risk assessment for risk to aquatic organisms did not pose a level of concern for freshwater fish. Thus, EPA did not require on the Fiesta label a risk to fish in the environmental hazards section.

    Fiesta is also nontoxic to people and pets, hence the Caution Signal word which is only there due to possible dermal irritation, which is on the label.

    The NTA and sodium nitrate are formed as byproducts of manufacturing FeHEDTA. Once the concentrate is diluted (1:25) to the end-use product, only trace amounts of these impurities remain, and they are the same trace impurities that are found in all chelated-iron fertilizers. (Scotts Weed-b-gon has the same impurities but also at extremely low levels as it is already diluted.)

    All components of the formulation, including the inerts, impurities, and byproducts, were reviewed and approved by the EPA. In addition, the trace impurities were further assessed by two independent toxicological consulting companies, who both concluded that the amounts were well below levels of concern and did not warrant any additional warning on the label, even in California (Prop 65). These tests were at the highest label rates and assumed multiple blanket applications.

    The Government of Canada has conducted a science-based evaluation of NTA, called a screening assessment. Screening assessments address potential for harm to the general population (not including workplace exposures) and the environment. The Government of Canada has concluded that NTA is not harmful to the health of the general population at current levels of exposure.
    Additionally, although NTA has the potential to remain in the environment for a long time, it is not expected to accumulate in organisms; therefore, the Government of Canada has concluded that NTA is not entering the environment in a quantity or under conditions that constitute a danger to the environment.
  7. rlitman

    rlitman LawnSite Bronze Member
    Posts: 1,552

    That is absolutely the right way to handle things! My response about Fiesta not killing the fish was purely to help ecoguy sleep at night knowing that he didn't inadvertently kill anyone's fish. I'd never suggest telling a customer they're full of crap, regardless of whether or not they actually are.

    Not having a manufacturer's official response, the most you can say is "duh, sorry". With it, you can claim that you try hard to be responsible, you use due care in what when and where you apply, and did your best to not harm their pets. And you can back that up with a manufacturer's statement, and then ask what you can do to make them happy.

    I agree that the water getting clear suddenly is a warning. Copper based algicides would certainly have killed the fish. But unless you're prepared to take on aquaculture for this customer, I wouldn't suggest you provide advice in this direction (and certainly do NOT cast blame). Maybe spread some doubt, but tread lightly.
    Last edited: Feb 10, 2014
  8. ecoguy

    ecoguy LawnSite Member
    from Duncan
    Posts: 234

    Bottom line. We can all now be confident that Fiesta poses no danger to those we love :) Thanks everyone for your wise words.

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