Antifouling Paints Research Articles

Neurotoxicity and Oxidative Damage Induced from Exposure of Male Rats to Low doses of the Synthetic Environmental Contaminant Tributyltin

    Tributyltin chloride (TBT) is an organotin compound widely used in several high biocides for agro-industrial applications, such as fungicides, and marine antifouling paints leading to endocrine disrupting actions, such as imposex development in mollusks. The current study investigates DNA damage, changes in brain drug-metabolizing enzymes, lipid profile, and oxidative damage of TBT at low doses 10, 100, 250, 500, 1000, and 2000 μg/kg B.W. in male rats. The animals were divided into eight equal groups which treated daily by oral gavage for 45 days. Administration of TBT induced a dose-dependent increase in the DNA damage and TBARS. Also, it decreases the expression of the regulator of the antioxidant response (the levels of glutathione and the activities of GR, GPX, CAT, and SOD). TBT did not show any significant effect of brain drug-metabolizing enzymes (cytochrome b5 and cytochrome p450). TBT at 250, 500, 1000, and 2000 μg/kg B.W. showed significant increase in lipid profile (total cholesterol, triglyceride, and LDL), but HDL showed significant decrease. In conclusion, the obtained results provide evidence that exposure to TBT at low doses causes oxidative stress, DNA damage, and changes in biochemical parameters in a dose dependent manner.

Investigation of an Antifouling Compound from Sponge Siphonodictyon coralliphagum

Marine fouling is attaching organisms to objects floating or submerged in seashores, such as ships, docks, and offshore structures. The impact caused is the reduced lifespan of the thing attached to the biofouling. In addition, there was a spread of invasive species. The government and industries in the United States spend over 6.5 million dollars annually on their budget to overcome this problem. So far, the prevention of marine biofouling is using antifouling paint on ships and submerged structures. One of them is organotin tributyltin (TBT) proven effective for preventing fouling; however, it is not environmentally friendly. Sponge Siphonodictyon coralliphagum growing in Salibabu Island waters, Talaud Islands, with previously shown activities against prokaryotes, was collected and extracted by maceration using ethanol as a solvent. The extract was then added to the base paint with several compositions of 5%, 10%, and 25% applied to the paving block surface. Positive control uses paint with copper additives. The objects are then immersed in the seashore below subtidal depths. The observation was carried out every seven days until day 28. The paving block was observed on day 90 after immersion. Significant results were obtained where macrofouling was only able to grow in negative control and positive control. The extract sponge S. coralliphagum has vigorous antifouling activity against marine biofouling. Furthermore, the extract was fractionated using liquid chromatography and continued by testing their activity against Gram-positive and negative bacteria. Further investigation of NMR spectra from the active fraction to prokaryotic cells shows a cyclic aliphatic compound with several keto-enol functional and methyl aliphatic groups on their chain.

Exploring fishery waste potential as antifouling component.

Marine biofouling is a global issue with economic and ecological implications. Existing solutions, such as biocide-based antifouling paints, are toxic for the environment. The search for better antifouling agents remains crucial. Recent research focuses on eco-friendly antifouling paints containing natural compounds like enzymes. This study evaluates enzymatic extracts from fishery residues for antifouling potential. Extracts from Pleoticus muelleri shrimp, Illex argentinus squid, and Lithodes santolla king crab were analyzed. Proteolytic activity and thermal stability were assessed, followed by bioassays on mussel byssus thread formation and barnacle cypris adhesive footprints. All three extracts demonstrated proteolytic activity and 24-h stability at temperate oceanic temperatures, except I. argentinus. P. muelleri extracts hindered cyprid footprint formation and mussel byssus thread generation. Further purification is required for L. santolla extract to assess its antifouling potential activity. This study introduces the use of fishery waste-derived enzyme extracts as a novel antifouling agent, providing a sustainable tool to fight against biofouling formation.

Chemical versus Natural Biocide Compounds - Minireview on Antifouling Coatings

Marine biofouling is an old problem, known and studied for centuries, since the beginning of navigation. The accumulation of marine biofouling begins on the submerged portion of an ocean-going vessel or on any installation (equipments, pipes, platforms, etc.) within minutes of contact with seawater. Over time, this accumulation increases the ship's resistance, leading to increases in the physical resistance of the ship in the water, with negative consequences on fuel consumption and greenhouse gas emissions, high maintenance costs (due to corrosion), and a negative impact on the marine environment (due to the release of toic bioactive compounds into the environment and the transfer of invasive species). These environmental issues were identified and recognized by the IMO, which in the early 1990s, through the Marine Environment Protection Committee (MEPC), adopted a resolution recommending that member governments adopt measures to eliminate TBT-based antifouling paints. These recommendations have led to the identification, development, and application of new antifouling technologies that could provide the maritime industry with a significant potential opportunity with an innovative, cost-effective, and efficient approach to the effects of marine biofouling. Our study aimed to make a small incursion in time, through the specialized literature on methods used to combat marine fouling, to highlight new research approaches to the identification and use of natural biocides to replace chemical ones. The targeting of research directions towards the identification of the most environmentally friendly antifouling compounds, in particular natural marine compounds, has been a focus of international researchers in recent years. To achieve this goal, going back to nature is currently the best option, as it could provide us with very effective models for research and development of antifouling coatings. In the development and modeling of new antifouling paints, the influence of the physical-chemical parameters of seawater (pH, salinity, temperature) on the chemical components (active groups) of the biocides used should not be ignored. The aim of this study is to highlight the importance of developing new antifouling paint technologies using biodegradable, non-toic, and environmentally friendly compounds according to international legislation. In recent years there has been an increasing emphasis in research studies on the combination of natural biocides (obtained through the valorization of marine wastes) with natural or synthetic hydrogels whose action is to minimize the attachment of marine fouling.

Adults of Sun Coral Tubastraea coccinea (Lesson 1829) Are Resistant to New Antifouling Biocides.

Biocides used in antifouling (AF) paints, such as 4,5-dichlorine-2-n-octyl-4-isothiazole-3-one (DCOIT), can gradually leach into the environment. Some AF compounds can persist in the marine environment and cause harmful effects to non-target organisms. Nanoengineered materials, such as mesoporous silica nanocapsules (SiNCs) containing AF compounds, have been developed to control their release rate and reduce their toxicity to aquatic organisms. This study aimed to evaluate the acute toxicity of new nanoengineered materials, SiNC-DCOIT and a silver-coated form (SiNC-DCOIT-Ag), as well as the free form of DCOIT and empty nanocapsules (SiNCs), on the sun coral Tubastraea coccinea. T. coccinea is an invasive species and can be an alternative test organism for evaluating the risks to native species, as most native corals are currently threatened. The colonies were collected from the Alcatrazes Archipelago, SP, Brazil, and acclimatized to laboratory conditions. They were exposed for 96 h to different concentrations of the tested substances: 3.33, 10, 33, and 100 µg L-1 of free DCOIT; 500, 1000, 2000, and 4000 µg L-1 of SiNC; and 74.1, 222.2, 666.7, and 2000 µg L-1 of SiNC-DCOIT and SiNC-DCOIT-Ag. The test chambers consisted of 500 mL flasks containing the test solutions, and the tests were maintained under constant aeration, a constant temperature of 23 ± 2 °C, and photoperiod of 12 h:12 h (light/dark). At the end of the experiments, no lethal effect was observed; however, some sublethal effects were noticeable, such as the exposure of the skeleton in most of the concentrations and replicates, except for the controls, and embrittlement at higher concentrations. Adults of T. coccinea were considered slightly sensitive to the tested substances. This resistance may indicate a greater capacity for proliferation in the species, which is favored in substrates containing antifouling paints, to the detriment of the native species.

Marine microdebris pollution in sediments from three environmental coastal areas in the southwestern Argentine Atlantic

Microplastics (MPs) and antifouling paint particles (APPs) are important components of marine microdebris (MDs), which constitute a potential environmental risk. This study analyzed baseline contamination levels of MDs and mesodebris (MesDs) in intertidal sediments at different depths, exploring the geomorphological influence in three Argentine coastal environments: Bahía Blanca Estuary (BBE), Los Pocitos (LP) and Puerto Madryn (PM). The MDs and MesDs samples were characterized by μ-FTIR, SEM/EDX and XRD. The abundance of MPs and APPs in sediments, range between 19.78 and 1087.19 and between 0 and 172.93 items/kg d.w., respectively. Despite variations in population and industrial developments in these areas, MPs abundance shows no significant differences in low and high intertidal zones. However, mean MPs concentrations were higher in the surface layer (0–5 cm) compared to the deeper sediments (5–10 cm), indicating recent MPs deposition. Chemical characterization evidenced the presence of cellulose (CE) and denser polymers as acrylonitrile butadiene styrene (ABS) and polyacrylics (PAN), APPs, metallic and black MDs. Surface degradation and heavy metals (Zn, Cr, and Ba) were also detected in APPs and other MDs, either as additives or adhered to their surfaces. Changes in crystallinity were also observed on the MesDs due to weathering. The calculated polymer hazard index (PHI) and the presence of hazardous polymers such as ABS and PAN indicated an increased risk of MPs pollution on the BBE and PM coasts. The pollution load index (PLI) values (from 4.63 to 5.34) suggested unpolluted to moderately polluted levels. These findings offer insights into potential risks associated with MDs in Argentine intertidal sediments, underscoring the critical need to comprehend the geomorphology and the influence of coastal dynamics. This is crucial for effectively addressing challenges linked to MDs pollution guiding the development of robust management and mitigation strategies.

Experimental Investigation of Paint Roughness on the Resistance of a Flat Plate

In this work, an experimental investigation of the hydrodynamic resistance of a flat plate painted with newly developed marine antifouling paints of polyurethane (PU) and silicone (Si) formulations was performed. In total, six different paint systems of Si, PU, and acrylic formulations were applied, both experimental and commercial. The total resistance of each painted condition of the plate was measured through towing tank tests for the range of 0.75–2.5m/sec, with a step of 0.25m/sec. The Si and PU formulations exhibited similar hydrodynamic behavior, fluctuating around the smooth condition, whereas the acrylic system exhibited the highest resistance increase of all. The roughness function calculation was based on Ra and the correlation with the Colebrook roughness function was generally limited for most systems. Extrapolation to ship scale revealed that no significant drag differences are expected in the as-painted condition among the different paint system types.

Recent Progress in Marine Antifouling Technology Based on Graphene and Graphene Oxide Nanocomposite Materials

Sea vessels and artificial sea‐based structures are severely affected by biofouling, i.e., the formation of deposits of living and dead marine organisms that belong to different species and range in size from unicellular bacteria to multicellular seaweed and mussels. This is a significant engineering problem since they essentially alter the geometry of the hull, increasing friction and reducing the speed of vessels, thus increasing the cost and environmental footprint of transportation. Given the scale of global transportation reaches several billion tons per year, the socioeconomic consequences of the reduction in transit speed and increased consumption of fuel continue to drive researchers and engineers to develop strategies to combat the processes of marine biofouling. Many types of antifouling paints, coatings, and materials that have been designed and tested, and in some instances used commercially, suffer from shortcomings ranging from environmental toxicity to limited efficiency and durability. In this review article, a brief overview of the traditional antifouling materials is presented and recent achievements in the design of advanced antifouling materials based on such nanomaterials as graphene, nanotubes, nanoparticles, and more complex nanostructures are discussed. These materials exhibit excellent antifouling properties and candrive a breakthrough in how marine biofouling is tackled.

Studi Eksperimen Pengaruh Ekstrak Kulit Nanas terhadap Laju Pertumbuhan Mikrofouling

Biofouling often sticks to the ship's hull, even to the propeller parts and pipes that are submerged in water. The existence of this biofouling has an impact on the ship's performance, reducing it and requiring more fuel, which ultimately contributes significantly to increased costs. Microfouling is one of the stages of biofouling growth that appears in a matter of days to weeks with a size of up to 1 mm which can be characterized by the appearance of a slippery layer on the surface of the specimen. Until now, many antifouling paints, as a means of preventing the occurrence of biofouling, still contain TBT, which has serious side effects as a chemical pollutant. Pineapple peel is a waste that is often found in Indonesia and contains bromelain and tannin which are anti-bacterial. The appearance of bacteria is the first phase in the growth of biofouling which is usually called biofilm, so it is hoped that pineapple peel extract will be able to prevent the emergence of biofilm. To determine the effectiveness of pineapple peel extract, this experimental study was carried out. The method used was a Randomized Block Design on ASTM 36 steel plate which is a certified ship material with 3 variations and 1 control of specimen as follows, 3 specimens as controls, 3 specimens with a ratio of 30% pineapple peel extract, 3 specimens with a ratio of pineapple peel extract. 50%, and 3 specimens with a pineapple peel extract ratio of 70%. Immersion for 7 weeks was carried out at Boom Beach, Banyuwangi by calculating the DGR (Daily Growth Rate) once a week. The DGR results obtained were respectively 0.095 g/day at an extract ratio of 30%, 0.0727 g/day at an extract ratio of 50%, and 0.0730 g/day at an extract ratio of 70%.

Determination of organotin compounds in marine sediments from Arctic Svalbard and West Antarctic Fildes Peninsula

This study investigated the contamination levels of five typical organotin compounds in Arctic and Antarctic marine sediments. Organotin total concentrations ranged from not detected (ND) to 37.9 ng Sn/g dw and from ND to 34.0 ng Sn/g dw in surface sediments of Svalbard and Fildes Peninsula, respectively. Dibutyltin accounted for 11.3 %–100 % of butyltins in Arctic sediments, whilst diphenyltin was the predominant phenyltin species in both Arctic and Antarctic. However, the concentrations of tributyltin and triphenyltin were lower than low-substituted organotins in the study areas, indicating the effectiveness of international ban on the use of triorganotin-based antifouling paints. No significant difference in organotin contamination was found between Arctic and Antarctic, although the time suffered from human interference was shorter in the Antarctic. Overall, these data can provide a diagnosis of recent organotin inputs in polar regions and serve as a baseline for future study assessing their local applications.

Comparative Investigation of AquaSun Eco-Friendly Antifouling Coating via Rheological and Mechanical Characterization.

Rheological and mechanical comparative tests of the new AquaSun antifouling sol-gel coating coated on shipbuilding steel compared to a commercial silyl acrylate antifouling top coat containing cuprous oxide and copper pyrithione show further evidence of the practical viability of this multifunctional coating for the protection of the immersed surfaces from biofouling. AquaSun is a less rigid or less viscous material than commercial top coat but more adherent to the steel substrate. These results support further investigation of this multifunctional sol-gel coating as an eco-friendly antifouling paint.

Comparison of the accumulation and effects of copper pyrithione and copper sulphate on rainbow trout larvae

Copper pyrithione (CuPT) is used as a co-biocide in new antifouling paints but its toxicity remains little known. To compare the toxicity of copper-based compounds, rainbow trout (Oncorhynchus mykiss) larvae were exposed for 8-day to CuPT and CuSO4 at equivalent copper concentrations. CuPT exposure led to the greatest accumulation of Cu in larvae. Exposure to 10 µg.L−1 CuPT induced 99% larval mortality but only 4% for CuSO4-exposed larvae. The larval development and growth were affected by CuPT (from 0.5 µg.L−1 Cu) but not by CuSO4. Lipid peroxidation was not induced by either contaminant. The expression of genes involved in oxidative stress defence, detoxification and copper transport was induced in larvae exposed to CuSO4 and CuPT but at higher concentrations for CuPT. This study highlights the marked toxicity of CuPT for early life stages of fish and raises the question of the possible environmental risks of this antifouling compound.

How do biocidals affect the non-target marine organisms: the short-term effects of antifouling agent sodium pyrithione on Mediterranean mussels (Mytilus galloprovincialis, Lamark 1819).

The metallic pyrithiones are used as antifouling paints for marine vehicles against fouling organisms. However, they are dissolved in marine water and have negative impacts on marine non-target organisms. This study evaluated the adverse effects of sodium pyrithione (NaPT) on Mytilus galloprovincialis using total hemocyte counts (THCs), oxidative stress and antioxidant parameters, and histopathological observations. Mussels were exposed to 0.1 and 1 μg/L NaPT for 96 h. The THC values of the NaPT-exposed mussels significantly decreased (p < 0.05). Lipid peroxidation and advanced oxidative protein products of digestive gland and gill tissues were decreased but only the digestive gland tissues of 0.1 μg/L NaPT values were significantly decreased compared to control groups (p < 0.05). Histological alterations were observed in the gill and the digestive gland tissues revealing malformations and hyperplasia of gill lamella; degenerations and loss of tubules of digestive gland after exposure to NaPT for 96 h. As a result, biocidal sodium pyrithione has adverse effects on the mussels even in short-term exposures and low concentrations.

Behavior of biocide-free foul control paints for ships’ hulls in the immediate proximity of ICCP anodes

AbstractImpressed current cathodic protection systems are used in combination with organic coatings to prevent corrosion of hulls. The reaction species which are formed in the proximity of the anodes, like chlorinated compounds and acidity, can stress the antifouling paints of the protective coating system. A 3 × 3 matrix was defined to drive the tests aiming to investigate the behavior of novel biocide-free foul release (FR) and self-polishing (SP) paints under this kind of attack. The matrix was featured by different pH and free chlorine (free-Cl) values derived by a galvanostatic test performed at an anodic current density required for the protection of paints roughly at their mid age. Chemical/physical characterization was performed through visual analysis, thickness measurements, profilometry, contact angle measurements, and FTIR-ATR analysis. Both FR and SP paints underwent adhesive failure only in the harshest conditions, pH = 3/free-Cl 3–6 ppm, with unmodified chemistry of the polymers. Both paints exhibited no detachment in milder pH/free-Cl conditions, but thickness and contact angle reduction were observed. Finally, results were discussed inferring possible behaviors of the tested paints in real applications.

Research Progress of Natural Products and Their Derivatives in Marine Antifouling.

With the increasing awareness of environmental protection, it is necessary to develop natural product extracts as antifouling (AF) agents for alternatives to toxic biocides or metal-based AF paints to control biofouling. This paper briefly summarizes the latest developments in the natural product extracts and their derivatives or analogues from marine microorganisms to terrestrial plants as AF agents in the last five years. Moreover, this paper discusses the structures-activity relationship of these AF compounds and expands their AF mechanisms. Inspired by the molecular structure of natural products, some derivatives or analogues of natural product extracts and some novel strategies for improving the AF activity of protective coatings have been proposed as guidance for the development of a new generation of environmentally friendly AF agents.

Antibacterial Properties of AquaSun Sol–Gel Coating

The antimicrobial activity, surface features, wettability, and adhesion of photocatalytic xerogel AquaSun deposited on shipbuilding steel in comparison to those of a commercial antifouling paint are investigated. The antimicrobial activity of AquaSun deposited on a steel substrate pretreated with primer and tiecoat paint exposed to a microbial consortium composed of Bacillus aquimaris and Pseudomonas poae is significant and of broad scope. Taking into account the low cost, high stability, and lack of ecotoxicity of this hybrid sol–gel coating, these results are promising en route to developing novel antibacterial coatings of broad applicability.

ANTIFOULING AND ANTICORROSIVE PREVENTION WITH CERAMIC COATINGS ON OFFSHORE STRUCTURES FOR RENEWABLE ENERGY

In the past, ships, port facilities and offshore platforms dedicated to the exploitation of fossil resources were the only man-made structures that were exposed to seawater, currently the exposed structures are extended to all those used in the field of renewable ocean energy sources, such as waves, tidal flows or oceans streaming and offshore wind energy. Therefore, this study highlights the need for offshore structures to consider the choice of ceramic coatings in the field of surface treatment and marine corrosion control without neglecting another of the main problems that affects structures in contact with seawater, which is the phenomenon known as biofouling. Corrosion is a major problem in offshore environments due to extreme operating conditions and the presence of aggressive corrosive elements. The corrosion resistance can represent the difference between trouble-free long-term operation and costly downtime. On the other hand, biofouling, which is defined as the undesirable phenomenon of adherence and accumulation of biotic deposits on an artificial surface that is submerged or in contact with sea water, can cause variations in the weight distribution of a floating structure, affecting its stability. In addition, biofouling leads to corrosion in the same way that corrosion leads to biofouling, so both factors are studied in parallel.&#x0D; This study evaluated differences in the total of seawater biofouling attached on coated paints and ceramic coatings in carbon steel for offshore structures. All three different ceramic coatings were made of incorporating active ceramic particles against biofouling as titanium, cobalt and manganese. In this study, the ASTM-D3623 test method, for the protection of submerged marine structures, was used. This method covered the procedure for testing antifouling coatings exposed for a period of two year at an immersion site with a high biological activity in shallow marine environments.&#x0D; The results of the investigation showed that the cobalt-based coating had the best antifouling properties at the end of the experimentation, although there was no significant difference in the biofouling attached during the two years of exposure, but great differences were shown with respect to the antifouling paints. Biofouling adhesion resistance was greatest when a coating thickness of 217 μm was used and when the substrate surface roughness (Ra) was 0.245 µm. The results indicated up to more 30% total area covered by biofouling in paint coatings than ceramic coatings. On the other hand, the results showed a progressive degradation of the antifouling paint coatings, which meant an exponential increase of biofouling adhered to the samples, but not in ceramic coatings during the two years experiments.

Metals and suspended solids in the effluents from in-water hull cleaning by remotely operated vehicle (ROV): Concentrations and release rates into the marine environment

An increase in the use of ROVs for in-water hull cleaning (IWC) has led to the need to understand the risks to the marine environment posed by the release of IWC effluents. The primary objective of this research is to investigate the characteristics of wastewater generated during IWC, specifically concerning suspended solids (SS) and metal concentrations, and their release rates and total load to the environment. The IWC effluents contain substantial amounts of SS and metals, with Cu and Zn being the most prevalent. These metals are predominantly associated with fine antifouling paint particles, posing a potential risk of secondary pollution upon release into the marine environment. While the treatment systems demonstrated effectiveness in reducing SS and particulate metals, achieving complete removal of dissolved and particulate metals below ambient levels proved to be challenging. To mitigate environmental risks, this study proposes, based on the particle size analysis, the implementation of multistage filtration systems with an optimal filtration pore size for the effluent treatment. In conclusion, we highlight the potential environmental risks of IWC activities. As most metals have a strong affinity towards particles in wastewater, effective removal of particles is essential to alleviate environmental stress at IWC sites.

Immunotoxic effects of exposure to the antifouling copper(I) biocide on target and nontarget bivalve species: a comparative in vitro study between Mytilus galloprovincialis and Ruditapes philippinarum.

Edible bivalves constitute an important bioresource from an economic point of view, and studies on their immune responses to environmental pollutants are crucial for both the preservation of biodiversity and economic reasons. The worldwide diffusion of copper(I)-based antifouling paints has increased copper leaching into coastal environments and its potential impact on both target and nontarget organisms. In this study, immunotoxicity assays were carried out with short-term (60min) cultures of hemocytes from the bivalves Mytilus galloprovincialis-a mussel dominant in the macrofouling community-and Ruditapes philippinarum-a clam dominant in the soft-sediment community-exposed to CuCl to compare the toxic effects on their immune responses. The LC50 values were similar, 40μM (3.94mgL-1) for the mussel and 44μM (4.33mgL-1) for the clam. In both species, apoptosis occurred after exposure to 1µM (98.9μgL-1) CuCl, the concentration able to significantly increase the intracellular Ca2+ content. Biomarkers of cell morphology and motility revealed microfilament disruption, a significant decrease in yeast phagocytosis and lysosome hydrolase (β-glucuronidase) inhibition beginning from 0.5µM (49.5μgL-1) CuCl in both the mussel and clam. The same concentration of CuCl affected biomarkers of oxidative stress, as a significant decrease in reduced glutathione content in the cytoplasm and inhibition of mitochondrial cytochrome-c oxidase (COX) were detected in both species. Comparison of the biomarkers showed that clam is more sensitive than the mussel regarding alterations to the lysosomal membrane and reactive oxygen species (ROS) production, which supports the potential harmful effects of antifouling biocides on the survival of nontarget pivotal species in the coastal community.

Communities of Fungi on Plates Coated with Antifouling Paint Modified by Nanoparticles

Communities of Fungi on Plates Coated with Antifouling Paint Modified by Nanoparticles