Marine

New tech could allow for more eco-friendly barnacle control on boats

New tech could allow for more ...
A sample piece of hull material painted with (bottom) and without the ivermectin-laced paint
A sample piece of hull material painted with (bottom) and without the ivermectin-laced paint
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A sample piece of hull material painted with (bottom) and without the ivermectin-laced paint
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A sample piece of hull material painted with (bottom) and without the ivermectin-laced paint

Barnacles may look nice and nautical on things like rocks, but they’re a major problem for watercraft of all sorts. On the hulls of ships, for example, they can drastically decrease the vessel’s hydrodynamics, causing it to burn more fuel and emit more emissions in order to maintain its cruising speed. The most common way of keeping barnacles off those hulls involves the use of environmentally-unfriendly paints. Now, however, a scientist from Sweden’s University of Gothenburg has developed what could be a less harmful alternative.

In regular “anti-fouling” hull paints, toxins such as copper oxide are mixed into the paint. That poison gradually leaches out of the paint, repelling would-be barnacle hitch hikers, but also entering the marine ecosystem. Various research institutes are looking at the use of more innocuous substances, such as a seed-inspired coating, electrified paint, and even a twitching polymer.

U Gothenburg post-grad student Emiliano Pinori has taken yet another approach. Instead of copper oxide, he’s mixed an antiparasitic agent known as ivermectin with regular hull paint. Unlike the copper, very little of the substance leaves the paint. Instead, barnacles come into contact with it only once they attempt to penetrate the paint’s surface. They’re then poisoned, and fall off the vessel.

According to Pinori’s research, a concentration of just 0.1 percent ivermectin is sufficient to render a paint barnacle-proof, with the anti-fouling effect lasting for “many years.” While small amounts of ivermectin still do leach into the water, he is hoping to get that amount down to zero.

Emiliano isn’t the only scientist at the university who’s investigating new methods of keeping barnacles off boats. Other Gothenburg researchers have recently explored the use of bacteria-produced macrocyclic lactones, and a veterinary medicine known as medetomidine.

Source: University of Gothenburg

18 comments
Slowburn
I think making the hull emit gamma rays would be less toxic over all.
shawnhcorey
If the barnacles are poisoned, then their dead bodies contain some of the toxin. Meaning some of the ivermectin will always get into the environment.
pTeronaut
@slowburn. That's all we need, giant green angry barnacles. LOL. Still, poisoning shellfish with will become part of the aquatic food chain and poison whatever eats it, is not the answer.
Slowburn
re; pTeronaut To clarify. There is no chance that gamma rays will result in FLKs because gamma rays denature DNA resulting in cell death; it does not rewrite DNA. A beam of light it does not leave toxins behind even if it is way higher frequency than the eyes can normally see.
Gadgeteer
pTeronaut, Ivermectin is already in widespread use as a de-worming drug for humans, dogs and farmed fish. Don't assume that just because something is toxic to one form of life that it is likewise dangerous to all species.
Slowburn
I am not a chemist but I would guess that in nature Ivermectin breaks down faster than copper oxide. re; Gadgeteer Just because it kills the host slower than it kills the parasite does not mean it is not toxic to the host. From https://en.wikipedia.org/wiki/Ivermectin Toxicity and potential drug interactions The main concern is neurotoxicity, which in most mammalian species may manifest as central nervous system depression, and consequent ataxia, as might be expected from potentiation of inhibitory GABA-ergic synapses. Dogs with defects in the P-glycoprotein gene can be severely poisoned by ivermectin.
Doug MacLeod
Ivermectin is used in farming sheep to kill parasitic insects. I lived in a sheep farming district where the ivermectin used in the sheep dip found its way into the rivers. Once there, even in tiny concentrations, it killed all the invertebrates which meant the fish had nothing to eat, so there were no fish. Paint may retain ivermectin initially, but the bonds which hold paints together degrade when exposed to weather and sunlight (just look at a harbour full of boats fading and peeling). The ivermectin will eventually be released with devastating consequences for the small sea animals which feed the fish. "Field studies have demonstrated the dung of animals treated with ivermectin supports a significantly reduced diversity of invertebrates, and the dung persists longer." So, a sea devoid of invertebrates and full of undigested excrement. No thanks.
Gadgeteer
Ah, yes, Slowburn, ever the master of Google and always someone with a better idea on every Gizmag story. Out of curiosity, has any scientist, researcher, corporation or inventor profiled in Gizmag articles ever adopted one of your suggestions?
The Skud
I enjoy reading Slowburn to see what he can up with - this one is a beauty! Make the hulls emit gamma rays? How? Electro-plate the hulls with plutonium? And do you suggest it only for cargo carriers (less crew to die from cancer) or all boats (passengers glowing in the dark - Hey, save on lighting)? How many ports would want radio-active hulls in their harbours?
Slowburn
re; Gadgeteer I can not say they got the idea from me of course but before there was this. www.gizmag.com/gravitylight-gravity-powered-led-lamp/25394/ GravityLight tackles weighty issue of lighting in the developing world By Darren Quick December 10, 2012 There was this. www.gizmag.com/nomad-portable-solar-lighting-system/22263/ I would prefer to see a light without batteries but with a spring or gravity powered generator. The gravity power unit is just a weight and string on a reel. For camping and backpacking the weight could be a boot or full water bottle. Slowburn 23rd April, 2012 @ 07:20 pm PDT re; The Skud I was thinking cobalt 60 and only on ships with steel hull plating at least 2 inches thick. Done right and it is safe for crew and passengers. Gamma rays do not cause secondary radiation. Not that it would harm anybody in a well run port but that would be a problem. Lets go with X-rays instead. We will need a outer hull with a high transparency to X-rays and a lot of X-ray tubes but they can be turned on and off at will.