Antifouling Companies Struggle with the Loss of Herbicide Irgarol


Your go-to antifouling paint may be different than it was last season.

As a boat owner, debunking the science of which bottom paint to use can be puzzling. Choosing the right antifouling for your boat will depend on many factors including your location, the current and the water temperature as well as what type of boat you have and how frequently you use it. Success with a particular bottom paint usually equals a loyal brand customer who relies on similar results season after season.

So then, if a main ingredient that was touted as being *key* to the antifouling side of boat bottom paint all of a sudden disappeared from the contents, are we ill fated to depend on our tried and true (maybe even blue!) paint? Enter Irgarol: The algaecide supplied by chemical giant BASF and widely relied upon by most marine paint manufacturers to control “soft growths” like slime and plant growth that has very recently been discontinued as a bottom paint ingredient.

BASF seems to have caught the bottom paint industry off guard with their announcement late last year, and while manufacturers of the Irgarol dependent paint hope that in just 6-9 months it could be in production again, there is no guarantee, and certainly these companies had to act quickly to be ready for bottom paint season with an alternative. There are a number of popular antifouling paints that are being affected by BASF’s discontinuation of Irgarol.

As a distributor of most of the bottom paints listed above, when Jamestown Distributors got word about the Irgarol shortage, we, like many other suppliers, ordered as much stock as possible of these Irgarol formulated paints to help customers seamlessly prepare for spring launching.  Supplies are limited, however we do have these paints in stock and will sell them while inventory lasts. In fact the non-Irgarol replacement paints are also already in stock and for sale by most suppliers, including JD, and we have worked hard on our website to make sure it is clear to customers whether the paint you are buying contains Irgarol or doesn’t.

The moral here: Buyers, be aware of what you are buying.  It may not be apparent to you as the consumer if you are using paint with Irgarol or paint without Irgarol. Read the labels carefully.  The cans look similar, the type in most cases is small and it can be difficult to tell the two formulas apart.

Jamestown Distributors is sharing this information with our customers because our nearly 40 years of experience and expertise with marine coatings has proven that consumers care about the ingredients and performance of their bottom paint.  Our own line of six different TotalBoat bottom paints were all developed without Irgarol and we are obviously glad to stand tall in the industry with our own proven growth-fighting bottom paints, without the distraction of reformulating our product line.

So be informed, read your paint can labels, check the product descriptions at and monitor your paint’s performance this season. Additionally, we invite you to come aboard the JD Bottom Paint Survey, and be a part of our own research & development of antifouling paints and their performance specific to your boat’s location.  The more we know, the more YOU know!

Happy Antifouling! Let’s go boating!

12 thoughts on “Antifouling Companies Struggle with the Loss of Herbicide Irgarol

  1. Pingback: More bad news for 'anti-slime' bottom paints - SailNet Community

  2. Pat Pat,
    Take a good look at this. We may have to key to what they don’t know yet. If nothing else our product as a additive in those name brand antifowling paints. Revive-It may work on it’s own, I don’t know for sure yet. We would have to test it down at coast to be sure.

    • Irgarol is currently not available from the supplier and is therefore curtailed in bottom paint production. BASF originally said it could be unavailable for 6-9 months, but they are making no promises and have said nothing more about it since announcing the supply issue to the paint manufacturers in the fall of 2014.

  3. You may not find the name Irgarol® on a label as the EPA mandates that the chemical name be used
    On the label of an antifouling paint look for this name

  4. Will the new formulation of SR-40 adhere well to the previous applications of SR-40? Or is this another factor we cannot not know yet, since this is the first season of the new product?

    I always understood that when adding a layer to ablative paints, it was best to use the exact same product to insure excellent adhesion and some mystery of compatibility.

    Even if it seems just one ingredient is missing, sounds like the manufacturer had to change something else in the formulation to make it work. (And there will not have been a season to test the new formulation in real conditions).

    But, while I am asking about adding layers, here is a second question: can a layer of Pettit SR-60 theoretically be added just as effectively to previous seasons’ Pettit SR-40?

    Thank you for clarifying.

    • Irgarol is only an anti slime additive
      It does not significantly change the chemistry of the paint.
      The bottom should be clean and sanded lightly and the new paint can be applied
      Most ablatives are compatible…you just cant put a hard paint over a soft ablative, or ANY other paint over a teflon racing finish.
      You can always call the tech line and ask questions! We are ready to help…800-423-0030

  5. Pingback: Bottom paint blues | Happenings at Sage Marine

  6. I have used bottom paint with Irgarol (Interlux ACT) since it first came out in a south facing bay on Cape Cod. It has not worked well on soft growth in my area. Interested to know where it has been effective.

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