COPPER EMISSIONS FROM 

ANTIFOULING PAINT ON

RECREATIONAL VESSELS

Kenneth Schiff*1,

Dario Diehl1,

Aldis Valkirs2

1

 Southern California Coastal

Water Research Project. Westminster, CA 02683

www.sccwrp.org

2

 Computer Sciences Corporation. San Diego, CA

* author to whom correspondence can be addressed:

714.372.9202 kens@sccwrp.org

June 22, 2003

Technical Report #405
Copper emissions from antifouling paint

2

ABSTRACT

Trace metals, especially copper, are commonly occurring contaminants in harbors and

marinas. One source of copper to these environs is copper-based antifouling coatings

used on vessel hulls. The objective of this study was to measure dissolved copper

contributions from recreational vessel antifouling coatings for both passive leaching and

hull cleaning activities. To accomplish this goal, three coating formulations, including

hard vinyl, modified epoxy and a biocide free bottom paint were applied on fiberglass

panels and placed in a harbor environment. In situ measurements of passive leaching

were made using a recirculating dome system. Monthly average flux rates of dissolved

copper for the hard vinyl and modified epoxy coatings were 3.7 and 4.3 μg/cm2/day, 

respectively, while flux rates for the biocide free coating was 0.2 μg/cm2/day. The

highest passive flux rates were measured initially after cleaning activities, rapidly

decreasing to a baseline rate within 3 days, regardless of coating formulation. Hull

cleaning activities generated between 8.6 and 3.8 μg dissolved copper/cm2/event for the 

modified epoxy and hard vinyl coatings, respectively. Aggressive cleaning using an

abrasive product doubled the copper emissions from the modified epoxy coating, but

produced virtually no change in the much tougher hard vinyl coating. When compared 

on a mass basis, roughly 95% of copper is emitted during passive leaching compared to 

hull cleaning activities over a monthly time period for a typical 9.1 m power boat.

Keywords: antifouling paint, copper, recreational vessel, hull cleaning, passive leaching
Copper emissions from antifouling paint

3

INTRODUCTION

Trace metals have been identified as important constituents of concern contaminating

sediments in marinas and harbors. For example, sediment quality surveys around the

nation routinely find high copper concentrations in marinas and harbors (US EPA 1996a, 

NOAA 1994). Where dissolved trace metals in the water column are measured, they

frequently exceed levels of concern in marinas (Hall et al. 1988; Zirino et al. 1978, Zirino 

et al. 1998). These elevated trace metal concentrations in marinas partly result from the 

physical processes of mixing and dispersion. Marina and harbor areas are inherently

protected thus providing calm water for navigation, but at the same time this restricts

circulation. To exacerbate the lack of mixing, marina and harbor areas typically have a 

multitude of potential contaminant inputs. Some of these marina and harbor areas might 

host local point sources such as municipal or industrial wastewaters. Many of these

marina and harbor areas likely receive surface runoff, which will vary in water quality as 

a function of the development within the adjoining watershed. However, all of these

marina and harbor areas receive inputs from vessel activities. There are a variety of

activities associated with vessels that could contribute trace metals including antifouling

paint hull coatings, sacrificial anodes, motor exhaust, and hazardous material spills. 

Of all the vessel related activities, antifouling bottom paints are amongst the largest 

source of trace metals, in particular copper. Current day hull coatings are impregnated

with copper and sometimes co-biocides whose goal is to retard the growth of algae and 

other encrusting organisms. These encrusting organisms will foul hulls and other 

underwater parts that will impede progress underway, lengthening transit times and

increasing fuel consumption (WHOI 1952). The copper impregnated coatings are

designed to slowly release copper, in the dissolved and most toxic form, so as to retard 

growth and maintain a smooth underwater surface. 

There are more coating formulations than there are coating manufacturers. Aside from

the active ingredient, which typically varies from 20 to 76% copper content, hull coatings 

also have a variety of formulations for the inert matrix and delivery. There are selfpolishing copolymers, ablative, and epoxy-based formulations. The passive flux of

copper from each of these formulation differs as a result of the matrix. For example,

epoxy-based coatings use a honeycomb matrix that enables the impregnated cuprous

oxide to leach through “micro-channels” in the coating. Regardless of the release

process, each of these coating formulations requires periodic (ca. monthly) underwater

hull cleaning to maintain a smooth surface and improve the copper release on pleasure

craft. Hence, the biocide does not prevent fouling, it merely prolongs the natural process 

of hard substrate recruitment and succession. 

Since there are numerous variations in copper content and matrix formulations, paint

manufacturers have developed a standard method for estimating biocide release rates

(ASTM 2000). Copper release rates are measured from coated rotating cylinders exposed 

to artificial standard seawater under controlled temperature and pH conditions. After an

initially high flux and when the release rate has stabilized, the copper release rate is
Copper emissions from antifouling paint

4

calculated by sampling the seawater in which the drum is immersed. Other investigators

have reported that the ASTM methods generate flux rates that are higher than in situ

measurements under static conditions, and under environmental exposure (Schatzberg

1996, Thomas et al. 1999)

The goal of this study was to assess the contributions of dissolved copper to receiving

waters via antifouling coatings from recreational vessels. The objective was to measure 

these contributions in-situ to estimate flux rates under environmentally relevant

conditions. The primary question addressed by this study is a comparison of dissolved

copper flux rates for both passive leaching and hull cleaning activities. Three

subquestions were also addressed in this study relevant to dissolved copper release rates 

from antifouling coatings. The first subquestion focused on quantifying the change in

dissolved copper flux during passive leaching between cleaning events as biofilms, algae,

and other encrusting organisms begin to grow on coated surfaces. The second

subquestion focused on quantifying the effect of best management practices (BMPs) on

hull cleaning activities. This is important since BMPs are a potentially important

mechanism for controlling antifouling coating discharges. The third subquestion focused

on evaluating the effect of different coating formulations. Differences among coating

formulations may produce differential flux rates for copper during both passive leaching

and underwater hull cleaning activities.

METHODS

There were three design factors investigated including coating formulation, cleaning

method, and time since underwater cleaning (Table 1). There are three basic types of

bottom coatings available to boat owners that we evaluated. Each varies in its biocide

content and mode of action. These included hard vinyl, modified epoxy, and biocide-free 

coatings. We measured the copper flux of each coating type during passive leaching, and 

again during underwater hull cleaning activities. 

The flux of copper was quantified using two different methods of underwater hull

cleaning. The first was a hand method by a professional underwater hull cleaning 

company using BMPs. The BMP paradigm mandates using the softest cleaning materials 

possible in order to minimize copper contributions and maximize the lifetime of hull

coatings. The second method was a non-BMP hand cleaning method using a more

abrasive cleaning material than was necessary to remove fouling.

Time since cleaning was evaluated by measuring the flux of copper during passive

leaching at periodic intervals following a cleaning event. Since most recreational vessels

are cleaned on monthly schedules (sometimes slightly less during winter or slightly more

during summer) by professional services, an interval of 1, 3, 5, 7, 14, and 28 days was 

selected.
Copper emissions from antifouling paint

5

Hull Surfaces and Coatings 

Fiberglass panels from a local boat manufacturer were used to simulate a recreational

boat hull. These 40.6 cm wide x 40.6 cm high x 0.48 cm thick panels were prepared for 

antifouling coating application by removing wax, lightly sanding the gel-coat, and

applying two coats of non-sanding primer. Two coats of paint were then applied onto the 

panels with a roller. After drying, panels were hung from the side of a boat dock in

ambient seawater 40 cm below the surface in a randomly assigned order. Similar to any

recreational vessel, a professional boat hull cleaning service provided monthly

maintenance beginning 60 days after submersion prior to the initiation of the sampling

phase . The exception was the biocide-free coated panels that were cleaned every two 

weeks upon emersion as a result of rapid fouling.

Two commercially available antifouling coatings and a biocide free coating were tested

in the study. The antifouling coatings had cuprous oxide (Cu2O) as the primary biocide 

within an insoluble matrix of modified epoxy or hard vinyl enhanced with TeflonTM. The 

matrix for the biocide free coating was a two-part epoxy with TeflonTM. A standard

application technique was applied to all panels regardless of coating types to ensure

biocide release rates would not vary as a result of coating thickness or other application 

variable. 

Sampling for Passive Leaching of Coated Surfaces

Passive leaching was measured using a closed, recirculating system (520 ml min-1) 

developed by the US Navy (Seligman et al. 2001, Valkirs et al. 2003). Each system

consisted of a 30.5 cm diameter polycarbonate dome with a double edge gasket

connected to Teflon hoses and a peristaltic pump. For each coating type, a randomly

selected panel was placed in a pre-cleaned 59 L plastic tub filled with ambient seawater. 

Each panel was gently placed into the tub followed by the dome system. After purging

all air from the system, the dome was pressed onto the sunny-side of the panel and

hydrostatically attached using negative pressure by removing a small volume of water

from the system. Water samples were then drawn from the system every 15 minutes for 

one hour. A pressure gauge monitored the system for leakage and allowed dome volume 

calculations. Filtered samples were collected from each composite using a 50 mL syringe 

fitted with a 25 mm diameter filter cassette using 0.45 μm pore size Metricel filters. 

Samples were preserved with nitric acid to pH < 2. 

Sampling for Cleaning Activities

Panel cleaning activities were sampled using precleaned 59 L plastic tubs filled with

ambient seawater, which prevented advective losses of copper due to currents and harbor 

mixing. Three panels were randomly selected from each coating type and gently placed 

in individual tubs. At time zero, a sample was collected from each tub as a blank. 

Immediately following, each panel was cleaned either using a BMP or nonBMP method, 
Copper emissions from antifouling paint

6

then removed at the end of 5 minutes. Particles were allowed to settle for one hour and a 

second water sample was collected from the tub. BMPs vary among underwater hullcleaning services. The BMP procedure selected for this study by a professional service 

agency used a low abrasive shag carpet and minimal applied pressure. The nonBMP

procedure selected for this study used an amateur individual with a nylon 3M scouring

pad with greater applied pressure. Filtered samples were collected from each composite 

using a 50 mL syringe fitted with a 25 mm diameter filter cassette using 0.45 μm pore 

size Metricel filters. Samples were acidified with nitric acid to pH < 2. 

In an effort to evaluate any bias between the use of a smaller panel system relative to an 

actual vessel hull, a validation experiment was conducted using actual vessels and a

BottomLiner boat bag. The boat bag is a rectangular plastic liner with a partially filled 

volume of 8,400L that submerses in a marina slip. The boat bag is closed on three sides 

to allow a boat to enter, then the fourth side closes to isolate the hull from the ambient 

environment. A total of 12 liters of water were collected at multiple locations and depths 

throughout the bag at time zero as a blank. The vessel was then cleaned using a

professional cleaning service with identical BMPs as used in the panel experiments. 

Particles were allowed to settle for one hour and a second 12 L composite water samples 

was collected. Filtered samples were collected from each composite using a 50 mL

syringe fitted with a 25 mm diameter filter cassette using 0.45 μm pore size Metricel

filters. Samples were acidified with nitric acid to pH < 2.

Analytical Chemistry

Filtered and acidified seawater samples were extracted using an iron-palladium 

precipitation technique following Bloom and Crecilius (1983). This extraction method

removes matrix related interferences to quantify copper at low levels (0.1 μg/L) in

seawater. The extract was reconstituted in deionized water and analyzed using Inductive 

Coupled Plasma Mass Spectrometry (ICP-MS) using EPA Method 1640 (U.S. EPA

1996b). Quality assurance measurements indicated that all laboratory blanks were below

method detection limits and duplicate samples were within a 10% reproducible percent

difference.

Data Analysis

Three types of data analysis were conducted for this study. The first analysis calculated 

dissolved copper flux rates for passive leaching from each coating type. The second

analysis calculated dissolved copper flux rates for each hull cleaning method from each

coating type. The third analysis compared the relative copper input of passive leaching to 

hull cleaning by estimating dissolved copper mass emissions for a typical vessel using the 

rates calculated in this study. 

Dissolved copper emissions and flux rates were determined for each coating type. 

Determination of passive leaching flux rates for each dome sampling event was estimated 
Copper emissions from antifouling paint

7

by first plotting each of the sample copper masses, calculated as the product of the

sample concentration and known volume of the dome sampling system, versus time over 

the course of the one hour sampling event. Flux rates, given as μg/cm2/day, were derived 

from the slope of the line based on linear regression of these samples (Zar 1984). Since 

these individual flux rates can vary by time since cleaning, an average flux rate for each

coating type was calculated by integrating the area under the curve of the one month 

passive leaching experiments. Since replicate curves were derived for each coating type, 

a t-test of slopes was used to test for significant differences in passive leaching copper

fluxes among coating types. 

Hull cleaning flux rates, either in tubs or boat bags, were calculated using one hour

samples corrected for time zero blank samples and any passive leaching that may have

occurred during this time period. The resultant concentrations were converted to

dissolved copper mass using the known surface area of the fiberglass panel or vessel hull, 

and the known volume of the tub or boat bag. The comparison among coating types and 

hull cleaning methods was accomplished using a non-parametric two-factor ANOVA

(Zar 1984). 

In an effort to compare the relative contributions of copper during passive leaching and 

hull cleaning, copper mass emissions were estimated for a typical 9.1 m by 2.7 m

powerboat. Surface area was estimated using the coating manufacturer’s formula

(Length * Beam * 0.85). Since hull cleaning occurs on a monthly basis, dissolved copper 

emissions were calculated over a 28 day time period.

RESULTS

Passive Leaching 

The enclosed system was able to measure in situ passive dissolved copper leach rates 

from fiberglass panels (Figure 1). Dissolved copper mass within the recirculating dome

system for hard vinyl coatings originated near 10 μg at time zero, then increased more

than one order of magnitude to 130 μg after one hour. Sequential samples collected over 

this time period increased in a strong linear fashion. We used this relationship to fit

curves that approximated passive leaching rates. The passive leaching rates for modified 

epoxy resulted in a very similar curve as hard vinyl coatings. In contrast, the biocide-free 

coatings had a very flat curve, demonstrating minimal leaching from this coating type.

Passive leaching rates varied between copper-based and biocide-free antifouling coatings 

(Table 2). As, expected, biocide-free coatings had passive leaching rates that were near 

zero. In contrast, mean passive leaching rates for copper-based antifouling coatings

varied from 3.7 to 4.3 μg/cm2/day. Although these copper-based passive leach rates

varied by 15%, they were not significantly different from one another. 
Copper emissions from antifouling paint

8

The passive leaching rates were highest immediately following cleaning events, then

rapidly declined until asymptotically reaching a baseline rate (Figure 2). Mean passive

leach rates for modified epoxy and hard vinyl coatings one day following cleaning

activities were 18 and 15 μg/cm2/day, respectively. This is the time period when panels 

were free of fouling by biofilms, algae, or other organisms. These rates decreased threefold within three days following cleaning activities, dropping to between 4 and 5

μg/cm2/day. Passive leach rates decreased slowly following day three, dropping to only 3 

μg/cm2/day after 28 days following cleaning activities. Biocide free coatings exhibited

minimal variability in copper concentration over time, remaining uniformly low to nondetectable.

Hull Cleaning

Contributions of dissolved copper during normal cleaning activities varied among all

three coating types (Table 2). The greatest fluxes, averaging 8.6 μg/cm2/event, arose

from the cleaning of the modified epoxy coated surfaces. The cleaning of the hard vinyl

coated surfaces produced dissolved copper fluxes that averaged roughly half the modified 

epoxy fluxes. Dissolved copper fluxes of biocide-free coatings were essentially zero.

The effect of BMPs can alter the flux of dissolved copper, depending upon the type of

coating being cleaned (Table 2). The lack of BMPs during cleaning events doubled the 

flux of dissolved copper from surfaces painted with modified epoxy antifouling coatings. 

The flux of dissolved copper did not change with or without the use of BMPs for either 

the hard vinyl or biocide free coated surfaces. The mean flux of dissolved copper from

hard vinyl coated surfaces remained near 4 μg/cm2/cleaning. The flux of dissolved

copper from the surfaces coated with the biocide free formulation remained essentially

zero.

Estimates of Combined Mass Emissions

Passive leaching contributed more dissolved copper than hull cleaning activities for a

typical recreational vessel on a monthly basis (Table 3). A 9.1 m powerboat that is

cleaned every four weeks using BMPs was estimated to contribute between 22 to 26 g/mo 

of dissolved copper. Between 4 and 7% of these emissions arise from hull cleaning

activities, depending upon the type of coating. The remaining 93 to 96% of the copper 

emissions arose from passive leaching. The relative difference in loadings between

passive leaching and hull cleaning activities is a function of frequency. On a daily basis, 

the flux of dissolved copper was slightly higher for cleaning activities than passive

leaching (Table 2). However, most vessels are cleaned once per month, whereas passive 

leaching is a continuous process. 
Copper emissions from antifouling paint

9

DISCUSSION

Flux rates of dissolved copper varied in our study as a function of biocide content within

the coating, hardness of the coating matrix, development of biofilms and other fouling

organisms, amongst others. Release rates were highest for the modified epoxy coating in

this study. This paint had a greater copper content (57.7%) than then the hard vinyl 

(37.25%) or biocide free (0%) coating based upon the ingredients listed on the product 

container. Our study used three types of coatings, but there are many available on the

commercial and industrial markets including ablative and self-polishing copolymer 

coatings. Passive in-situ leach rates of dissolved copper from ablative paints used by the 

U.S. Navy were measured to average 3.9 μg/cm2/day (Zirino and Seligman 2002). 

Valkirs et al. (2003) measured passive leach rates that ranged from 8-22 μg/cm2/day after 

two months at steady state conditions from ablative in service and copolymer selfpolishing test coatings used on military vessels. In the United Kingdom, Thomas et al. 

(1999) found ablative leach rates that ranged from 18.6-21.6 μg/cm2/day in 17 day

experiments. Although ablative coatings appear to have a slightly higher flux rate, the

use of these coatings has diminished in recent years in civilian pleasure craft. 

Interestingly, the reduction in ablative coatings stems not from concerns about water 

quality, but rather from concerns about air quality. It appears that these coatings have a 

large volatile component that makes it difficult for most boatyards, at least in southern

California, to comply with clean air standards (Leigh Johnson personal communication). 

The hardness of the coating matrix appeared to alter the flux rates of dissolved copper, 

particularly during cleaning events. In the case of the present study, both the modified

epoxy and hard vinyl coatings were classified by the manufacturer as hard, insoluble

types that release biocide through contact leaching. However, water discoloration by

coating particles was observed during cleaning operations on panels with modified

epoxy, but not with the hard vinyl matrix. Moreover, the concentration of dissolved

copper was higher following cleaning activities in the softer modified epoxy coating,

which was only exacerbated when more abrasive cleaning techniques were applied. In

contrast, the most abrasive cleaning technique did not alter dissolved copper flux rates for 

the hard vinyl coating.

Biofouling quickly reduced and, ultimately, equalized the passive leaching rates of both

copper containing coatings examined in this study. Biofilms have been shown to alter

release rates (WHOI 1952, Mihm and Loeb 1988, Valkirs et al. 2003). Cleaning events 

allowed the passive leach rates of the paints to temporarily function above 10

μg/cm2/day, a leach rate known to retard biofouling (WHOI 1952, Caprari et al. 1986). 

However, as the biofilm layer increases it may sequester leached metals. As evidence of 

this, biofilms have been reported to contain high (1.3-3.5 μg/mg dry wt) copper

concentrations (French et al. 1984). 

One point of concern for our study design was extrapolation of our results from fiberglass 

panels to the hulls of recreational vessels. This concern appears unfounded, though,

because our measurements compared favorably to measurements from recreational vessel
Copper emissions from antifouling paint

10

hulls (Fig 3). Valkirs et al. (2003), using the in situ methodology used in our study, 

reported passive leach rates on seven different recreational vessels of varying coating

formulations with different copper content, time since application, and time since

cleaning. The mean passive leach rate of the recreational vessels was approximately

double the fiberglass panels (8 vs. 4 μg/cm2/day), but the range of measurements for the 

vessels encompassed the mean of our panel system. In fact, the range of measurements 

for the seven different recreational vessels was within the range of measurements for the 

fiberglass panels (2-26 μg/cm2/day) over our one month test period. Likewise, the flux

rates measured during hull cleaning events using fiberglass panels were comparable to

results measured from recreational vessels (Fig 3). Similar to isolating fiberglass panels 

in a dockside tub system, we were able to measure replicate vessels by isolating them

from the marina environment using a boat bag. The mean cleaning flux rate measured for 

the fiberglass panels and the boat bag systems were within 12% of each other. The range 

of hull cleaning flux rates from recreational vessels appeared much smaller than the

passive leaching flux rates, perhaps because the vessels were all similar in size, coating

formulation, time since application, and time since cleaning.

If managers wish to reduce dissolved copper emissions from hard vinyl or modified

epoxy antifouling coatings on recreational vessels, it is most efficient to alter coating

types rather than focus on hull cleaning BMPs. On a mass basis, 95% of the loading

from recreational hull coatings occurs via passive leaching. Therefore, even if a BMP

existed that reduced all of the dissolved copper emissions, the total cumulative reductions 

would amount to only 5%. Furthermore, most commercial hull cleaners attempt to clean 

coatings with minimal abrasiveness. They use these techniques to not only reduce copper 

emissions, but also to prolong the life of the coating. The use of BMPs may be more

effective on softer coatings such as copper-based ablative paints. Switching to nontoxic 

alternatives may be the most effective mechanism to reduce overall copper emissions, but 

this alternative comes with a sacrifice. In this study, the nontoxic coating alternative

fouled much more quickly, contained more “hard” growth (i.e. barnacles), and required

increased cleaning effort and time.

ACKNOWLEDGMENTS

The authors are deeply indebted to Dr. William R. Crawford III (Scuba Duba Corp), a 

businessman with tremendous integrity. Additional acknowledgements include Francois

Aquin and Shawn Whisnant (Scuba Duba Corp), Pete Michael (San Diego Regional

Water Quality Control Board), Kevin Kelly (Department of Pesticide Regulation), Peter

Seligman (US Navy), Leigh Johnson (University of California Sea Grant Extension 

Program), David Tsukada, Liesl Tiefenthaler, Drew Ackerman, Kerry Ritter and Steven

Bay (SCCWRP). Laboratory analysis was conducted by CRG Marine Laboratories

(Torrance, CA). Fiberglass panels were constructed by Crystaliner Corp. (Costa Mesa, 

CA). Boat bags were provided by Bottom Liner Corp. (Long Beach, CA). Portions of

this study were funded by the San Diego Regional Water Quality Control Board and the 

State of California Department of Pesticide Regulation.
Copper emissions from antifouling paint

11

REFERENCES

ASTM. 2000. Standard Test Method for Copper Release Rates of Antifouling Coating

Systems in Seawater., ASTM Method D 6442-99. 6pp. 

Bloom, N.S., and B.A. Crecelius. 1983. Determination of silver in seawater by

coprecipitation with cobalt pyrrolidine dithiocarbamate and Zeeman graphite-furnace 

atomic absorbtion spectrometry. Analytica Chimica Acta 156:139-145. 

Caprari, J.J., O. Slutzky, P.L. Pessi, and V. Rascio. 1986. A study of the leaching of

cuprous oxide from vinyl antifouling paints. Progress in Organic Coatings 13: 431-444. 

French, M.S., L.V. Evans, and R. Dalley. 1984. Raft Trial Experiment on Leaching from

Antifouling Paints. Trans. IMarE (C), Vol. 97, Conf.2, Paper 19. 127-130. 

Hall, W., S. Bushong, L. Hall, M. Lenkevich, and A. Pinkney. 1988. Monitoring

dissolved copper concentrations in Chesapeake Bay. Environmental Monitoring and

Assessment 11:33-42 

Kiil, S., C.E. Weinell, M.S. Pedersen, K. Kam-Johansen. 2001. Analysis of selfpolishing antifouling paints using rotary experiments and mathematical modeling. Ind.

Engineering and Chemical Research 40:3906-3920. 

Mihm, J.W., and G.I. Loeb. 1988. The effect of microbial biofilms on organotin release 

by an antifouling paint. In Biodeterioration 7 (pp. 309-314). D.R. Houghton, R.N. Smith 

and H.O.W. Eggins (Eds.). Elsevier Applied Science, London. 

NOAA. 1994. Inventory of chemical concentrations in coastal and estuarine sediments. 

NOAA Technical Memorandom, NOS ORCA 76. Natinal Oceanic and Atmospheric

Administration, National Ocean Service. Silver Springs, MD. 

Schatzberg, P. 1996. Measurement and significance of the release rate for tributyltin. 

Chapter 19, pp. 383-403. In: Organotin: Environmental Fate and Effects. M.A. Champs 

and P.F. Seligman Eds. Chapman and Hall. New York. 623pp.

Seligman, P.F., A.O. Valkirs, J.S. Caso, I. Rivera-Duarte, and E. Haslbeck. 2001. Copper 

release rates from antifouling marine coatings and its relationship to loading and toxicity

in San Diego Bay, California. In: Symposium on Pollution Prevention from Ships and 

Shipyards. Oceanology International 2001 Conference. Miami, Florida, April 4-5, 2001. 

M.A. Champ, Ed. pp. 64-81. 

Thomas, K., K. Raymond, J. Chadwick, and M. Waldock. 1999. The effects of shortterm changes in environmental parameters on the release of biocides from antifouling

coatings: cuprous oxide and tributyltin. Applied Organometallic Chemistry 13:453-460. 
Copper emissions from antifouling paint

12

US EPA. 1996a. The national sediment quality inventory: A report to Congress on the 

extent and severity of sediment contamination in surface waters of the United States. US 

Environmental Protection Agency, Office of Science and Technology. Washington, DC. 

EPA-823-D-96-002 

US EPA. 1996b. Method 1640: Determination of Trace Metal Elements in Ambient

Waters by On-Line Chelation Preconcentration and Inductive Coupled Plasma-Mass 

Spectrometry. U.S. Environmental Protection Agency, Office of Water, Engineering and

Analysis Division, Washington, D.C.

Valkirs, A.O., P. F. Seligman, E. Haslbeck, J.S. Caso. 2003. Measurement of copper

release rates from antifouling paint under laboratory and in-situ conditions: implications

for loading estimation to marine water bodies. Marine Pollution Bulletin, In press.

WHOI. See Woods Hole Oceanographic Institution.

Woods Hole Oceanographic Institution. 1952. Marine Fouling and Its Prevention, United 

States Naval Institute, Annapolis, MD. Contribution No. 580. 388 pp. 

Zar, J. 1984. Biostatistical analysis. Prentice Hall. Engelwood Cliffs, NJ. 718 p

Zirino, A., S.H. Lieberman, and C. Clavell. 1978. Measurement of Cu and Zn in San

Diego Bay by automated anodic stripping voltametry. Environmental Science and

Technology 12: 73-79. 

Zirino, A., S.L. Belli, and D.A Van der Weele. 1998. Copper concentration and CuII 

activity in San Diego Bay. Electroanalysis 10, 423-427. 

Zirino, A. and P.F. Seligman. 2002. Copper Chemistry, Toxicity and Biavailabilitry and 

Its Relationship to Regulation in the Marine Environment. Space and Naval Warfare

Systems Center Technical Document 3140. San Diego CA
Copper emissions from antifouling paint

13

Table 1. Number of treatments for each of three factors evaluated during the antifouling 

coating project. All treatments had three replicates.

Treatment Factor

No. of 

Treatment

s

Passive 

Leachin

g

Underwat

er Hull 

Cleaning

Notes

Coating Types 3 Yes Yes Modified Epoxy, Hard Vinyl, Biocide-free

Cleaning Types 2 No Yes BMP (nonabrasive) vs nonBMP (abrasive) on all three 

coatings

Time Since 

Cleaning 7 Yes No Day 1, 3, 5, 7, 14, 21, 28 on all three coatings
Copper emissions from antifouling paint

14

Table 2. Mean flux rates (95% confidence intervals) of dissolved copper for three types of 

commercially available antifouling coatings for passive leaching, hull cleaning using best 

management practices (BMPs), and hull cleaning without BMPs.. 

Mean Dissolved Copper Flux

Modified Epoxy

Hard

Vinyl Biocide Free

Passive Leaching (μg/cm2/day) 4.32 (0.44) 3.71 (0.86) 0.24 (0.08)

 

Hull Cleaning (μg/cm2/event) 

BMP 8.57 (0.70) 3.84 (1.55) 0.03 (0.02)

No BMP 17.45 (1.65) 4.18 (0.35) 0.05 (0.03)
Copper emissions from antifouling paint

15

Table 3. Estimated mean dissolved copper mass emissions (grams per month) for three 

coating types (hard vinyl, modified epoxy, and biocide free) for a 9.1 m powerboat. 

Flux (g/mo)

Modified Epoxy

Hard 

Vinyl

Biocide 

Free

Passive Leaching 24.9 21.4 1.4

(Min - Max) 23.3 – 27.8 15.7 – 24.5 0.9 – 1.8

 

Underwater Hull Cleaning with BMPs 1.8 0.8 <0.01

(Min - Max) 1.7 – 2.0 0.5 - 1.2 0.00 - 0.01

 

Total Emissions 26.7 22.2 1.4

(Min - Max) 20.5 - 33.6 15.0 – 31.5 0.9 – 1.8

 
Copper emissions from antifouling paint

16

Figure 1. Passive leach rate curve for dissolved copper from a hard vinyl, modified epoxy, 

and biocide free antifouling paint. All data were collected 14 days after underwater 

cleaning.
Copper emissions from antifouling paint

17

Figure 2. Mean (+ std dev) changes in passive leaching of dissolved copper from three 

types of hull coatings (hard vinyl, modified epoxy, biocide free) over 28 days following a 

cleaning event.
Copper emissions from antifouling paint

18

Figure 3. Ratio of mean (min, max) dissolved copper flux rates for passive leaching or hull 

cleaning activities from recreational vessels relative to fiberglass panels used in this 

experiment. Data for passive leaching from recreational vessels from Valkirs et al (2003). 

Passive Leach Hull Cleaning

Recreational Vessel / Fiberglass Panel

0.0

0.5

1.0

1.5

2.0

2.5

3.0

3.5