I:\MEPC\55\2-4.doc For reasons of economy, this document is pr inted in a limited number. Delegates are kindly asked to bring their copies to mee tings and not to request additional copies. INTERNATIONAL MARITIME ORGANIZATION

IMO 

# E

MARINE ENVIRONMENT PROTECTION
COMMITTEE
55th session Agenda item 2 MEPC 55/2/4 21 April 2006 Original: ENGLISH

HARMFUL AQUATIC ORGANI SMS IN BALLAST WATER

Basic Approval of Active Substances used by EctoSysô electrochemical system

Submitted by Sweden

SUMMARY

Executive summary: This document contains non-confidential information for Basic Approval of Active Substances used by EctoSysô electrochemical system as required by the Procedure for approval of Ballast Water Management systems that make use of Active Substances (G9). Relevant documents together with the application dossier have been submitted to Marine Environment Division of the Organization for review by the GESAMP ñ Ba llast Water Working Group in accordance with the provisions of the above mentioned procedure.

Action to be taken: Paragraph 6

Related documents: BWM/CONF/36, MEPC 53/24/Add.1, BWM.2/Circ.4

Introduction

1 Regulation D-3.2 of the International Conve ntion for the Control and Management of Shipsí Ballast Water and Sediments stipulates that Ballast Water Management sytems that make use of Active Substances to comply with the Convention shall be appr oved by the Organization.

2 The Procedure for approval of Ballast Water Management systems that make use of Active Substances (G9) adopted by resolution MEPC.126(53) defi nes principle aspects to be documented by data or testing (MEPC 53/24/A dd.1, annex 4, paragraph 4.2.1) and some basic principles for risk evaluation (MEPC 53/24/ Add.1, annex 4, paragraph 5.3). According to section 6 of the Procedure (G9) the Organization should evaluate the information provided in the application.

3 According to BWM.2/Circ.4 proposals for appr oval of Ballast Water Management systems
that make use of Active Substances are to be submitted to Marine Environment Division of the Organization to be reviewed by the GESAMP-Ba llast Water Working Group. In the meantime, a document on the proposal for approval containing all the non-confidential data related to the respective Active Substance need s to be submitted to MEPC 55.MEPC 55/2/4 - 2 -

I:\MEPC\55\2-4.doc 4 The competent authority in Sweden has ve rified the application dossiers prepared by Permascand AB and believes them to satisfy the data requirements of the Procedure (G9).

5 Sweden therefore submits the non-confidential part of the app licantís dossier in the annex of this document to the Organization for ev aluation according to the Procedure (G9). The complete dossier will be made available to the experts of the GESAMP-Ballast Water Working Group with the understandi ng of confidential treatment.

Action requested of the Committee

6 The Committee is invited to consider the pr oposal for approval and decide as appropriate.

***MEPC 55/2/4

I:\MEPC\55\2-4.doc ANNEX

1 INTRODUCTION

The applicant is proposing an electrochemical syst em, the EctoSysô, as the disinfection step in a complete system for ballast water treatment. EctoSysô is an electrochemical system utilizing electrodes with high oxygen overpot ential, and therefore producing powerful disinfectants such as the hydroxyl radical directly into the me dia and also providing direct oxidation of microorganisms and other contaminants on the el ectrode surface. In addition, small amounts of harmless disinfecting by-products (i .e. free active chlorine) from th e cell prevent regrowth in the tanks and biofouling, and by the ce ll design and electrode configur ation preventing the formation of secondary chlorinated organics such as for example trihalomethanes (THM:s). The EctoSysô is designed for purification a nd disinfection in high flow app lications with conductive medias
such as natural sea water or br ackish water. One single, compact module can be dimensioned for treatment of flows up to 500 m 3 /h, with no additional chemicals and a minimum of maintenance needed. The EctoSysô is typically used for ballast water treatment as the disinfecting step after mechanical separation (e.g. filters, hydrocyclones) of contaminants down to 40-45 μm scale. The water is typically treated both dur ing ballasting and deballasting.

An electrochemical cell working with a natural wa ter media such as sea water could theoretically produce an endless number of va rious oxidative species. Howe ver, the oxidative species and by-products produced in the EctoSysô either has a very short degradation time, are produced in extremely low concentrations (in the order of natural occurrence in sea water) or are completely harmless. The air emissions resulting from tr eatment will contain oxygen gas and small amounts of hydrogen gas and carbon dioxide. Neither the Active Substances nor any of the relevant chemicals are bio accumulative or persistent and will ultimately degrade under environmental conditions to oxygen, water, carbon-dioxide and chloride in detectable levels.

The key factors for the EctoSysô electrochemical system are the electr ode type and the cell design. Permascand AB has over 30 years of experience in developing, producing and characterizing different kinds of electrochemical cells, electrodes an d catalytic coatings used by the electrochemical industry. Different kinds of electrodes and coatings are used for different industrial applications a nd - in the case of treating ballast wa ter - by using cataly tically inactive electrodes with high oxygen- and hydrogen overpotentials it is pos sible to selectively produce the desired highly oxidative species (i.e. hydroxyl radicals) without the problems associated with
conventional chlorine electrolysis.

2 APPLICATION FOR THE USE OF CHEMICAL ACTIVE SUBSTANCE

The use of ìActive Substancesî by this electroc hemical system refers to the descriptions and definitions given in the Procedure for approval of Ballast Water Management systems that make use of Active Substances (G9) adopted by re solution MEPC.126(53) and does not fall under the Directive 98/8/EC of the European Parliame nt and of the Council of 16 February 1998 concerning the placing of biocidal products on the market (the Biocidal Products Directive, BPD). Article 1 of Directive 98/8/EC lays down th e scope of the Directive, which concerns the authorization and placing on th e market for the use of biocidal products. According to Article 3(1), Member States shall prescribe that a biocidal product shall not be placed on the market and used in their territory unless it has been authorized in accord ance with the Directive.
Authorization is defined in Arti cle 2(1)(i) as an administrativ e act by which a Member State authorizes the placing on the market of a biocid al product. On the basis of the definition of authorization in Article 2(1)(l) there is an e xplicit link between authorization and the placing onMEPC 55/2/4

ANNEX Page 2

I:\MEPC\55\2-4.doc the market, whereas at present, no reference is made to the use of the product. Placing on the market is defined in Article 2(1) (h) as a supply and there is no re ference to the us e. There is no supply when the production of th e Active Substance takes place in situ without involving precursors that are not placed on the market. Ou r interpretation of ìManual of Decisions for Implementation of Directive 98/8 /EC concerning the placing on the market of biocidal productsî is that placing on the market of hydroxyl radica l- and active chlorine producing equipment (for waters naturally containing chloride) does not fall within the scope of BPD to the extent that no biocidal products or precursors for biocidal products are placed on the market. The users of the EctoSysô equipment are not within the scope of the BPD to the extent that they use the equipment to produce and use the Active Substances on their own site, without placing them on
the market.

Due to the fact that the proposed electrochemical ballast water disinfection system EctoSysô is not based on the supply or addition of any chemi cals to the water to be treated, the testing and
characterization of the Active Subs tances in the Procedure (G9) may not be applicable at all points. Furthermore, one of the Active Substances (i.e. hydroxyl radicals) in question has such a short half-life that it is not possible to charact erize it from the point of view of persistency, bioaccumulation, endocrine disruption etc. which is a major part of the Procedure (G9). The main disinfecting effect of the hydroxyl radicals produced will take pl ace inside the electrochemical system itself (within a few micrometers from the electrodes), and will not (beside some residual regrowth preventing effect originating from activ e chlorine species) occur in other parts of the ballast water system either on the ship or after discharge of the ballast water back to the sea.

This application for the use of an electrochemi cal system, EctoSysô, which makes use of Active Substances to treat ballast water, will focus on whole effluent toxicity testing and chemical specification of ballast water trea ted under relevant conditions. Ho wever, characterization of the
function and environmental fate of the Active S ubstances and relevant chemicals will also, if applicable, be shown in this application for Basi c Approval. The whole-effluent toxicity testing will be supplemented by a computer model of the dilution of the ballast water in the sea or in harbours after discharge.

3 IDENTIFICATION (THE PROCEDURE (G9), SECTION 4.1)

EctoSysô generates the Active Substances in situ in the ballast water st ream without adding any precursors, active or non-active, to the water. No commercial fo rmulation, including additives or not, are added in the Ballast Water Management sy stem in order to comply with the Convention. The highly oxidative Active Substance primarily produced by EctoSysô in natural waters such
as marine sea water/brackish waters is the hydroxyl radical, OHï. This species under normal
circumstances has a half-life in the order of nanoseconds, and thus never leaves the cell (or the reaction zone) with the water flow . The hydroxyl radical very effi ciently inactivates and breaks down microorganisms and other contaminants. No chemically active l ong-lived residuals are formed at relevant concentrations in this pro cess using this electrochemical treatment method and specially developed electrochemical cell. Indir ect disinfection and also direct oxidation of microorganisms on the electrodes will only contribut e to the Total Organic Carbon (TOC) level.

Because of the nature of an electrochemical trea tment and the complexity of natural waters, it is not possible to make a complete ac count of all chemical species formed in the reactor. However,
the Active Substances and relevant chemicals that can be produced at detectable concentrations are easily identified. Th ese are as follows:MEPC 55/2/4

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I:\MEPC\55\2-4.doc • Hydroxyl radical, OHï : a very reactive oxidative species with half-life in the order of nanoseconds, thus never leaving the reactor. Secondary radical s may also be formed in very small amounts as intermediates in th e degradation processes of other oxidative species. The hydroxyl radical will be referred to as an ìA ctive Substanceî of this
electrochemical ballast water disinfection method.

• Free Active Chlorine : due to the sea water content of chloride ions, small amounts of chlorine gas (Cl 2 ) will form as a by-product on the anode surface and will further, by
favourable interactions with the cathode due to the EctoSysô cell design, immediately form other free active chlorine sp ecies (0.05-2 ppm) HOCl and/or OCl - depending on the pH. These small amounts of free active chlorine will contribute to prevent regrowth/biofouling in the ballast tanks and to the most extent ultimately degrade back into chloride ions. Due to the composition of the EctoSysô electrochemical cell, the primary produced chlorine gas will very rapi dly (by cathodic interact ions and water) form the active chlorine species, thus preventing th e formation of harmful chlorinated organics such as for example THM:s. Free active ch lorine will be referred to as ìActive
Substanceî due to their oxidative and disinfecting abilities.

• Hydrogen gas, H 2 (g): will be formed at the cathode due to water electrolysis ñ however, due to the composition of the electrochemical cell, the main cathode reactions will be reduction of oxygen gas (O 2 ) and the small amounts of ch lorine. Hydrogen gas will be referred to as a ìRelevant chemicalî in this application due to the safety aspects of this

gas.

As will be shown by this proposal, none of the Activ e Substances or Relevant Chemicals used in or caused by EctoSysô ballast water treatment will form any kind of threat to the ship, crew or
environment.

4 ELECTROCHEMICAL DISINFECTION PROCESSES

4.1 The ballast water problem

The need for ballast water treatment (BWT) or iginates in the hazardous introduction of alien species (e.g. algaes, copepods, vertebrates etc.) into new bi otopes, where they may cause enormous damage to the local eco system and its populations of native species. Planktons and microorganisms as a total group vary greatly in fo rm, colour, and habits, as well as in size. The variety is enormous. For exampl e, in one classification alone, the Diatomacea , it is estimated that there are over 10,000 species, ea ch of which has its own distinct ive shape, pattern or design. Some microorganisms live only in sunlight, others in the dar k. Some are aerobic requiring oxygen for their existence; others are anaerobic and grow in the absence of air. They may be mobile or non-mobile. Microorganisms grow, in cold or hot water and even under ice. This variety results in very high de mands on universally functional BWT systems. No ballast water treatment system, using Active Substances or not, will ever be able to guarantee a 100% efficiency (kill rate) on all types of aquatic organisms. Surviving ba cteria, spores a nd viruses etc. will start to reproduce again as soon as the right conditions are provided. By the applicant, it is considered necessary to include some residual tr eatment effect, at least while ballast water is stored in the tanks to prevent regrowth.MEPC 55/2/4

ANNEX Page 4

I:\MEPC\55\2-4.doc 4.2 Oxidation processes in water treatment

Oxidation processes are commonly used in wate r treatment for disinfection and removal of obnoxious or potentially toxic contaminants in the water, and for some industrial purposes such as pulp bleaching and purificati on of wastewater before discha rge into the environment. The most familiar chemical oxidant is oxygen from ai r; other examples of oxidants used in water treatment are e.g. chlorine, chloramines, ozone, chlorine dioxide , hydrogen peroxide and potassium permanganate. Sometimes these oxidants are used in combination with each other (e.g. ozone with hydrogen peroxide) or with photons from irradiation lamps (i.e. UV treatment).

4.3 Electrochemical oxidation

During several years, there has be en great interest in developing effective disinfection processes based on electrochemistry, since it is an envi ronmentally friendly, lo w-cost, and convenient disinfection strategy to operate. In addition, electrochemical oxidation has been known to destroy a wide variety of microorganisms from planktons and bacteria to virus and algae. There are
various electrochemical disinfec tion processes, including the in situ electro generation of disinfection agents (oxidative species), electro-s orption of bacteria on the electrode surface,
electrocution and elec trophoresis. Especially, in situ production of chemical disinfectants has been intensively studied because it has an obvi ous appeal in that dangerous chemicals are not transported and stored. The EctoSysô is an electr ochemical system utilizing electrodes with high oxygen overpotential, and theref ore producing powerful disinfect ants such as the hydroxyl radical directly into the media and also providi ng direct oxidation of microorganisms and other
contaminants on the electrode surface.

One of the most common electrochemical water treatment processes generating a variety of
oxidants is the anodic oxidation. In the area of wastewater treatment, the anodic oxidation process has been widely used as the most simple and convenient method due to its high efficiency for degrading the chemical pollutants. This efficiency is provided by dual oxidation pathways involving the direct electron transfer between target chemical compounds and anode surface, and also indirect electron transfer mediated by reactive intermediate species formed from water oxidation and other reactants, such as for instance the hydroxyl radi cal (ïOH) and chlorine (Cl 2 ). By an electrochemical treatment of waters , either a partial (reduc tion of toxicity) or a complete decomposition of the pollutants can be achieved. In the case of organic materials, complete decomposition means the oxidation to carbon dioxide and as consequence a relatively high energy consumption for large organic molecu les [1]. The attempts for an electrochemical oxidizing water treatment can be cl assified into two categories: di rect oxidation at the anode or indirect oxidation mediated by oxidati ve species produced at the anode.

4.3.1 Direct Oxidation at the Anode

A model has been developed [2] to describe th e course of the anodic oxidation of an organic molecule assuming three major step s (a-c): (S indicates surface)

Discharge of water forming an adsorbed hydroxyl species:

S[ ] + H 2 O → S[OH] + H + + e - (a)MEPC 55/2/4

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I:\MEPC\55\2-4.doc The adsorbed OH is the ìactivated stateî of wate r in oxygen-transfer reac tions to the organic
molecule R:

S[OH] + R → S[ ] + RO + H + + e - (b)

Co-evolution of O 2 by oxidation of water diminish ing the current efficiency:

S[OH] + H 2 O → S[ ] + O 2 + 3H + + 3e - (c)

An organic contaminant (such as e.g. a microorgani sm in ballast water) may this way be rendered harmless by direct oxidation at th e anode surface in an electrochem ical cell. The electrodes used in EctoSysô works at high overpotentials and t hus have a high efficiency for direct oxidation (i.e ìcombustionî). The mechanism is induced even further by the favourable mass transport characteristics of the EctoSysô cell and by the fact that the cell wall of pathogenic microorganisms is negatively charged by nature and will be electrically attracted to the anode
surface.

4.3.2 Indirect oxidation

In pure water medium, the most typical anodic reaction is the oxygen evolution resulting from water oxidation through two-electron transfer reaction as describe d below by (Equation 1) similar to (c) above. This reaction is composed of tw o one-electron transfer reactions expressed by equations (2) & (3), involving the production of ïOH as the reactive intermediate. At a high anodic potential, also some ozone can be ge nerated by a six electr on transfer mechanism (Equation 4). This ozone production is negligibly small (non detectable by standard analysis methods) in the case of sea water electrolysis b ecause of the content of dissolved ions. When chloride ions (Cl - ) are present in the electrolyte (like in marine or brackish water), chlorine gas evolution can occur simultaneously as described by (Equation 5) below.

H 2 O → 1 / 2 O 2 + 2H + + 2e - E 0 = + 1.23 V (vs. NHE) (1)

H 2 O → ïOH + H + + e - (2)

ïOH → 1 / 2 O 2 + H + + e - (3)

3H 2 O → O 3 + 6H + + 6e - E 0 = +1.51 V (vs. NHE) (4)
2Cl - → Cl 2 + 2e - E 0 = + 1.36 V (vs. NHE) (5)

Even though many kinds of oxidants can be gene rated by anodic oxidation processes, most research and practical applica tion of electrochemical disinf ection for water has only paid attention to and focused on the production of fr ee active chlorine specie s and related compounds as disinfectant agents. However, bearing the pr oblems with disinfecti on by-products associated
with conventional chlorine disinfection in mind, during the development of the EctoSysô electrochemical disinfection system for treatment of marine waters focus has been laid on the potential of anodic oxidation proces ses as a powerful disinfection tool without considerable net production of chlorine gas, free active chlorine sp ecies and consequently no harmful by-products.

The factor above others influencing the selectiv ity for anodic production of different kinds of oxidative species is the electrode type used in the system. Conve ntional electrodes used in the electrochemical industry, such as for instance the DSAô type electrodes used in chlorine electrolysis, are in general strongly catalytical ly active in order to reduce the cell voltage and hence the power consumption of the electrolysis . The catalytic activity of these conventional electrodes entails the fact that they will, in water-based electrolytes, work at low electrode potentials because of the discharge mechanism of common water electr olysis where oxygen gasMEPC 55/2/4

ANNEX Page 6

I:\MEPC\55\2-4.doc (O 2 ) is formed at the anode and hydrogen gas (H 2 ) at the cathode. The tota l voltage span (the cell voltage) between the negative pote ntial of the cathode (at which H 2 is formed) and the positive potential of the anode (at which O 2 is formed) is cal led the ìelectrochem ical windowî of the electrode type in questi on. Of course, different el ectrode types and coatings can be used as anode and cathode respectively. The fact ors influencing the catalytic activ ity of different electrodes and coatings are many including chemical factors such as content of different elements but also physical such as e.g. wetability of the surface.

The electrochemical windows of conventional, cat alytically active, electrode types are small because of the low cell voltages and low absolute values of electrode pote ntials at which water electrolysis occurs. When these electrodes work with low potential absolute values, no highly oxidative species (e.g. hydroxyl radicals) can be produced on the electrode surface because other reactions (common water electrolysis and oxidation of chlo ride) are thermodynamically favored
under these conditions. The absolute dominant result of sea water electrolysis with conventional
electrochemical cells and elec trodes is anodic production of oxygen gas and chlorine, and cathodic production of hydrogen gas.

On the other hand, available on the market is also non-catalytically active electrodes with large electrochemical windows, i.e. electrodes that during electrolysis disc harges in oxygen- and hydrogen evolution at high electrode potentials. When using non-cat alytically activ e electrodes (such as for instance electrodes with conductiv e boron-doped diamond coati ngs) working at high absolute values of potential, it is possible to cr eate selectivity for the an odic production of highly oxidative species others than oxygen and chlorine. The selectivity for each theoretically possible species among each other is determined by fact ors such as the complexity of mechanism rendering the species in question. Hydroxyl radical s are highly thermodynamically favoured due to simple reaction mechanisms. Table 1 shows the oxi dation potential of some oxidative species.

Table 1: Oxida tion potential of different oxidative species

Oxidative species Oxidation potential, E 0 (V) Hydroxyl radical, ïOH 2.8 Superoxide, ïO 2 - 2.4
Ozone, O 3 2.1 Persulphate, S 2 O 8 2- 2.0 Hydrogen peroxide, H 2 O 2 1.8 Hypochlorite, OCl
- 1.7 Chlorine dioxide, ClO 2 1.5 Oxygen, O 2 1.2

The power of a chemical oxidant to cause a chemical oxidation reacti on is measured by two properties: (1) the thermodynamic driving force and (2) the rate constant of oxidation. The thermodynamic driving force of the oxidation pro cess for one oxidant compared to another is determined by its oxidation potential.

The oxidation potential is a measure of a chemi calís oxidizing (or reduci ng) power; the more positive the value of E 0 , the more likely is the chemical re action to take place as written. The
parameter E 0 is related to the free energy ∆ G 0 by the formula ∆ G 0 = ñ nFE 0 , where n is the
number of electrons transferred and F is the Faraday constant (9.648×10 4 J/V). For example, a large positive value of E 0 indicates that the substance in que stion is a powerful oxidizing agent, thus the hydroxyl radical is one of the most effective oxidants known.MEPC 55/2/4

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I:\MEPC\55\2-4.doc 4.4 Biological efficiency

Generally in water treatment, the ability to oxidi ze biological molecules and the ability to diffuse through the cell walls of microorganisms are requir ements of any effectiv e disinfectant. The cell wall of pathogenic microorganisms is negatively ch arged by nature. This means for example, in the case of disinfection processe s using free active chlorine, that the cell wall can be penetrated by the neutral hypochlorous acid ( HOCl) rather than by the nega tively charged hypochlorite ion (ClO - ). Hence the hypochlorous acid is a more e ffective disinfection sp ecies than hypochlorite ion. The equilibrium HOCl/OCl - is strongly pH dependent (see figure 1) and due to a pH of around 8 in sea water environment, BWT disinfec tion using free active chlorine will be less efficient than the equivalent treatment of e .g. drinking water. The surface charge of the contaminants/microorganisms is not influencing th e disinfection efficiency of radicals such as e.g. hydroxyl radicals.

The issue of pH dependence is also irrelevant concerning electrochemical disinfection using hydroxyl radicals. Hydroxyl radicals produced in sea water is neit her influenced by pH nor is influencing pH value themselves as long as the water contains oxidisable material. Thus EctoSysô treatment of sea water/brackish water will not have any impact on the pH value to a
relevant extent.

5 DATA-SET FOR ACTIVE SUBSTANCES AND PREPARATIONS (THE PROCEDURE (G9), SECTION 4.2)

5.1 Hydroxyl radicals

5.1.1 Properties (the Procedur e (G9), paragraph 4.2.1.5)

5.1.1.1 Chemical identity

CAS No.: 3352-57-6
IUPAC International Chemical Identifer: InChI=1/HO/h1H

Name: Hydroxyl radical

Chemical structure: O * H
Molecular formula: HO Molecular mass (g/mol): 17.01

(Source: NIST (National Institute of Sta ndards and Technology, USA) Standard Refe rence Database 69, June 2005 Release: NIST Chemistry WebBook)

5.1.1.2 Physical and chemical properties

The physical properties of the hydr oxyl radical, ïOH, are very ha rd to specify and the chemical properties are probably best describe d in terms of reaction rate constants in in teracting with other species. It can be concluded that the reactivity is extremely high and the half-life is in the order of nanoseconds. Hydroxyl radicals are very common in the environment due to their involvement as an intermediate species in various reaction ch ains occurring naturally, such as photochemical and biochemical processes.MEPC 55/2/4

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I:\MEPC\55\2-4.doc The most covering way to characterize the chemical properties of hydroxyl radi cals is to describe the reaction kinetics and proposed reaction mechanisms to various sp ecies. This has been studied
in ì Critical Review of Rate Constants for Reacti ons of Hydrated Electro ns, Hydrogen Atoms and Hydroxyl Radicals (

. OH/

. O

ñ ) in Aqueous Solution î, George V. Buxton et al.

, J. Phys. Chem. Ref.

Data 17 : 513-886 (1988). The kinetic da ta for the ïOH in aqueous solution and the corresponding radical anions, ïO

ñ and e aq ñ , have been critically review ed and can also be found at http://www.rcdc.nd.edu/compilations/Hydroxyl/OH.HTM. Reactions of the radicals in aqueous solution have been studied by pulse radiolysis , flash photolysis and other methods. Rate constants for over 4400 reactions, more than 6100 measured values are tabulated, including reactions with molecules, ions and other radica ls derived from inorgani c and organic solutes.

5.1.1.3 Disinfection properties

The immediate biocide action of the hydroxyl radical has been well recognized from massive experimental evidences, which demonstrate that disinfection processes using hydroxyl radicals are technically feasible. It is generally accep ted that reactive oxygen sp ecies (ROS) and hydroxyl radicals play the role of disinf ectants. For instance, studies have determined how the ïOH, acting either independently or in collaboration with other ROS, is quantitatively related to the
inactivation of E. coli . The results indicates that the ïO H is the primary oxidant species responsible for inactivating E. coli (in this specific study produced in the UV/TiO 2 process).

The exact mode of hydroxyl radicals (which belongs to the surface phase of the anode material) inactivating microorganisms is not fully unders tood. In attempts to understand the mode of hydroxyl radicals inactivating microorganisms, some research has been made with MS-2 phage
and E. coli , which are frequently used as indicators of virus and bacteria in disinfection study, respectively. MS-2 phage was inactivated main ly by hydroxyl radical in bulk phase, whereas
E. coli was inactivated by hydroxyl ra dical in both bulk and surface phases, and possibly some other reactive oxygen species such as ïO 2 - . Possible oxidants and mechanisms responsible for inactivating microorganisms in a nodic oxidation processes have b een identified in some cases. For instance, the role of hydroxyl radical on the inactivation of E. coli in anodic oxidation process under conditions where chlo rine species can not be formed (by using excess methanol as hydroxyl radical scavenger) has been investigated. It was ob served that the inactivationof E. coli occurred through two distinct stag es independently from the current density applied, which are characterized by the rapid inactivati on at an initial stage of electrolysis (1st stage inactivation) and a slower inactivation as the electrolysis pr oceeds further (2nd stag e inactivation). The two stages of inactivation seem to be related to the competition of two kinds of electron transfer reaction, which are similar to the degradation of chemical pollutants. In addition, as the evidence
for the occurrence of direct el ectron transfer reacti on, the existence of electro-sorption of E. coli cells facilitating the electron transfer between microbial cel ls and electrode surface was
identified.

5.1.2 Risk characterization and an alysis of hydroxyl radicals (the Procedure (G9), section 5.3)

5.1.2.1 Screening for persistence, bioaccumulation and toxicity

Persistence tests and bioaccumulation tests acco rding to the Procedure (G9), paragraphs 5.1.1.1 and 5.1.1.2, are not applicable on hydroxyl radicals due to their physical and chemical properties. The Active Substance of hydroxyl ra dicals used in th e EctoSysô disinfection system does not
fulfil the PBT criteria as outlined by the Procedure (G9) and EC, 2003a:MEPC 55/2/4

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I:\MEPC\55\2-4.doc Criterion PBT criteria

P (persistence) Half-life > 60d in marine water or > 40d in fresh water
or half-life > 180d in marine sediment or > 120d in fresh water sediment or readily biodegradable
B (bioaccumulation) BCF > 2000 or lgK OW > 4.5

T (toxicity) Chronic NOEC < 0.01mg/l or CMR or endocrine disruption effects.

Due to the extremely short half-lif e of the radical, it is obvious th at it is not persistent in the environment. The octanol-water partition coeffi cient (the Procedure (G9), paragraphs 5.3.7 and 5.3.11) is for the same reason not possible to calcul ate; therefore the issue of bioaccumulation is not relevant for hydroxyl radicals. The direct t oxicity of hydroxyl radicals to microorganisms is discussed below, but will never be a concern ou tside the electrochemical cell and therefore not after discharge of the ballast water.

Due to the nature of the el ectrochemical technology used, humans will not be exposed to hydroxyl radicals during any part of the ballast wa ter treatment process. Hydroxyl radicals will
never be handled and due to the short lifetime neve r leave the electrochemical reactor, thus will the discharge concentration (the Procedure (G9), paragraph 5.3.8) be zero at all times. The risk assessment will conclude no existent threats posed by the Active Substance to the environment, crew or ship.

Concerning direct toxicity tests on hydroxyl radicals, according to the Procedure (G9) (paragraphs 5.1.1.3, 5.3.9, and 5.3.10) in the case of hydroxyl radicals is very limited, also regarding data on mammalian toxi city (the Procedure (G9), para graph 4.2.1.2). Again, due to the material properties (short life time) of the hydr oxyl radical, regular toxicity tests, tests for bioaccumulation or endocrine disruption are impo ssible to perform or not relevant. The tests recommended by the Procedure (G9) are theref ore not applicable. The main approach to investigating/evaluating and arguing about the t oxicity is based on a whole-effluent discharge toxicity test approach descri bed under section 6 of this do cument, and on the comprehensive material regarding free active chlorine, whic h is also included. The mechanism of hydroxyl radical disinfection (i.e. acute ìt oxicityî to livin g organisms) is not fully understood but some
theories are included above under se ction 5.1.1.3 of this document.

5.1.2.2 Formation of hydroxyl radicals in the EctoSysô system (the Procedure (G9), paragraph 5.3.3)

The current exchange for hydroxyl radical form ation on electrodes used as anodes in the EctoSysô has been analyzed using a spectrophot ometric radical spin-tra p technique (using N, N-dimetyl-4-nitrosoanilin, RNO, as spin trap molecule selective to hydroxyl radicals) that is commonly accepted and has been desc ribed in literature [3]. The method has been modified by the applicant to simulate BWT conditions regarding salinity and electrochemical operating parameters of the EctoSysô. Experime nts where performed at bench-scale.

The results from these tests show that the cu rrent efficiency for hydr oxyl radicals on electrode materials used in EctoSysô can reach 25%, i.e. 25% of the appl ied current is used for anodic production of hydroxyl radicals on this type of el ectrode surface. The actual efficiency in the EctoSysô under relevant treatment conditions is believed to be higher due to favourable mass transport induced by the cell design. With this basic estimation of the electrode performance (25% current efficiency) and bear ing in mind that hydroxyl radical formation from water is a one electron transfer ope ration, approximately 1.6*10 -3 moles of hydroxyl radicals should be formed each second in an EctoSysô electrochemical cell dimensioned for treatment of 500 m 3 /h ballastMEPC 55/2/4

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I:\MEPC\55\2-4.doc water. A rough estimation of the content of microorganisms (of a ll classes) is 1*10 9 per litre. This would give an average dose of about 7*10 9 hydroxyl radicals per microorganism if 100% efficiency for this purpose is reached. Hydroxyl ra dicals will are not selec tive to certain species, and in sea water especially carbonate is a main scavenger. The remaining 75% of the applied current will mainly induce oxygen evolution, but also direct oxi dation of organic and inorganic materials on the electrode surface and small production of chlorine (Cl 2 ) as by-product.

The actual production of hydroxyl radicals in the EctoSysô electrochemical cell during ballast
water treatment under relevant conditions is no t known. The influence of physical parameters such as e.g. flow rate on the formation of hydr oxyl radicals has not been investigated. However this is not important from an environmental point of view or concerning safety aspects because the hydroxyl radicals will never leave the reactor due to their short half-life. It is noted that the hydroxyl radicals produced, along with the mass transfer efficiency of the cell, is suited to meet the criteria of sufficient ballast water treatment (Standard D-2 in IMO Ballast Water Management Convention). The total influence of the EctoSysô treatment of ballast water regarding change of physical properties and toxic ity is instead analysed taking a whole-effluent approach.

5.1.2.3 Produced secondary by-products from hydroxyl radicals

Hydroxyl radicals will act as ox idizing agent in various redox reactions involving all kinds of species present in the media. Hydroxyl radi cals does not form hal ogenated disinfection by-products (DBP:s) when particip ating in oxidation/reduction re actions with natural organic material. However, if bromide ion is present in raw water treated with hydroxyl radicals (such as sea water) halogenated DBPs may be formed to a higher extent than under normal environmental conditions. THM in sea water will ultimately to the most extent consist of bromoform, due to the stability of this substance and the sea water content of bromide ion, Br - . The total formation of THM in sea water during EctoSysô treatment is quantified and discussed under section 5.3.2
below.

5.2 Free active chlorine

Hypochlorite concentration should normally be expressed as % NaClO in common water disinfection applications. However, to allow a comparison between this document and legal criteria (which express NaClO solutions in term s of active chlorine content) the term ìFree
Active Chlorineî is used in this dossier.

5.2.1 Properties (the Proce dure (G9), paragraph 4.2.1.5)

The common physical properties of the free active chlorine species are not possible to account for specifically, because they will always form equilibrium in a solution and never (except Cl 2 gas) exist in their pure form. Therefore, the phys ical properties of the (relevant in this case) corresponding substance for sea water, s odium hypochlorite, will be shown accordingly.

(Note: Free active chlorine (in practice Cl 2 +HOCl+ClO - ) is expressed as equivalent content of
Cl 2 . As the molecular weight of Cl 2 is 71 g/mol and the molecular weight of NaClO is 74.4 g/mol, for sodium hypochlorite the equivalent active chlorine measured as the oxidizing power represents 95% of the sodium hypochlorite weight (M.W.Cl 2 /M.W.NaClO x 100 = 71 x 100/74.4).)MEPC 55/2/4

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I:\MEPC\55\2-4.doc 5.2.1.1 Chemical identity (the Pr ocedure (G9), section 4.1)

CAS No.: 7681-52-9
EINECS No.: 231-668-3

Name: Sodium hypochlorite

Chemical structure: Na + ClO Molecular formula: ClO.Na Molecular mass (g/mol): 74.4

(Source: RISK ASSESSMENT REPORT FOR SODIUM HYPOCHLORITE, DRAFT. Akzo Nobel NV, November 2005[7])

5.2.1.2 Physical and chemical properties

During storage of commercial solutions, hypochlori te is slowly transfor med into chlorate and chloride. The following data are valid for an aqueous solution with a content of 15% (w/w) available chlorine (IUCLID, 2001).

Table 2: Physical properties of sodium hypochlorite

Property Value References Physical state Liquid Melting point - 20 to -30°C Safety data sheet Hoechst AG 1994 Boiling point 96 ñ 120 °C Safety data sheet Hoechst AG 1994 Relative density 1.23 g/cm3 at 25°C Sicherheitsdatenblatt der Bayer AG Vapour pressure 17.4 - 20 hPa at 20°C Sa fety Data Sheet Rhone Poulenc Water solubility Miscible [29.3 g/100 g (0 deg C) in water] HSDB

Partition coefficient
n-octanol/water (log value) n.a. (logKow = -3.42, estimated) (online software at: http://syrres.com/esc/kowdemo.htm )

Granulometry n.a. Conversion factors Flash point n.a. Autoflammability Flammability Explosive properties Anhydrous sodium hypochlorite is very explosive HSDB

Oxidizing properties Strong oxidizing agent usually
stored and used in solution HSDB

Viscosity Henryís constant

(Source: RISK ASSESSMENT REPORT FOR SODIUM HYPOCHLORITE, DRAFT. Akzo Nobel NV, November 2005[7])

5.2.1.3 Disinfection properties

When diluted in water, depending on pH valu e (see figure 1 below), hypochlorite is partly transformed into hypochlorous acid (HOCl). This product is an extremely efficient biocide forMEPC 55/2/4

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I:\MEPC\55\2-4.doc prions, viruses, bacteria, parasi tes and fungi. HOCl reacts actively by chlorina tion of nitrogen on compounds like amino acids. It is thus very reac tive to proteins. With adapted levels of
concentration and contact times it can kill all the microorganisms. At much lower concentrations in water (0.1 to 1 mg/l) it is able to inhibit bacter ial growth. In this last case the proteins of the membrane are partly destroyed and the bacteria are not able to multiply (Techware Report, 1996;
Venkobachar et al. , 1977)

The disinfecting properties of fr ee active chlorine species in water are based on the oxidizing power of the free oxygen atoms and on chlorine substitution reactions. Free active chlorine species kills pathogens such as bacteria and viruses by breaki ng the chemical bonds in their
molecules. Disinfectants that ar e used for this purpose consist of chlorine compounds which can exchange atoms with other compounds, such as enzymes in bacteria and other cells. When enzymes come in contact with chlorine, one or more of the hydrogen atoms in the molecule are replaced by chlorine. This causes the entire mo lecule to change shape or fall apart. When enzymes do not function properly, a cell or bacter ium will die. Hypochlor ous acid (HOCl) can easily penetrate protective slime layers and cell walls of microorganisms, causing them to die or suffer from reproductive failure.

5.2.2 Classification

According to Directive EEC 67/548, annex 1 and its amendments sodium hypochlorite (Index-No. 017-011-00-1) is classified as follow:

Current classification accord ing to Annex 1 (29th ATP): Classification: C, N

R-sentences: 31-34-50 S-sentences: (1/2)-28-45-50 Specific limits:

C ≥ 10%: C R31-34
5% ≤ C < 10%: Xi R31-36/38

The C&L Technical Group at th e 15-18 March 2005 meeting, decided to maintain the above classification. According to th e Dangerous Substances Direct ive 67/548/EEC and subsequent amendments and to the Dangerous Prepara tion Directive 88/379/EEC, sodium hypochlorite
solutions are classified as follows:

• Solution less than 5%: Not classified;

• Solution from 5% to 10% available chlori ne: Irritant with the risk phrases R 31:
contact with acids liberates toxic gases and R 36/38: irritating to eyes and skin; and

• Solution above 10% available chlorine: corros ive with the risk phrases R 31: contact with acids liberates toxic gases and R 34: causes burns.

(Note: This classification include s the risk related to the sodium hydroxide always present as a stabilizer in concentrations up to 1% when so ld in solution and used in common applications. The free active chlorine related to EctoSysô BWT is formed in situ .)

Theoretical pure sodium hypochlorite should be clas sified as ìvery toxic to aquatic organismsî (N, R50) based on aquatic toxicity data, and as ìh armful for ingestionî (X n, R22) on the basis of
the oral LD50 data. This classifi cation does not apply to solutions as their concentration is alwaysMEPC 55/2/4

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I:\MEPC\55\2-4.doc below 25%, and especially not to the sea wate r treated with EctoSysô since the maximum
concentration of free active chlorine will never exceed 2 ppm (2 mg/l equivalent Cl 2 ).

5.2.3 Electrochemical formation of free active chlorine

On the anode surfaces of an electrochemical ce ll, oxidative species will be produced from the reactants available in the electrolyte. In the cas e of a sea water electrolyte, the most common reactant available will of course be water, H 2 O. When using conventional electrodes (such as DSAô types) the main product of this electrochemical process would be oxygen gas (O 2 ) evolving from the anode due to common water el ectrolysis (Half-cell reaction: Equation 1 above). When chloride ions (Cl - ) are present in the electrolyte (like in marine or brackish water), chlorine gas (Cl 2 ) evolution can occur simultaneously with the formation of hydroxyl radicals on the anode as described by (E quation 5) above. When Cl 2 is present, OCl - and HOCl will form spontaneously with water (Equation 6). Cl 2 will also have some selectiv ity to reactions with other substances (organic or inorganic) present in th e water, thus forming by-products that might be harmful such as for instance trihalomethanes, THM:s. However, in the EctoSysô electrochemical cell, the reduction of chlorine (oxidation number: 0) as Cl 2 to HOCl (oxidation number: -1) is mediated by intera ctions on the cathode, due to th at the cell desi gn and electrode configuration is especially de veloped to favour this purpose:

Cl 2 + H 2 O → HOCl + H + + Cl - (6)

(EctoSysô cell: this electron transfer me diated through rapid interaction of Cl 2 /H 2 O with cathode surface)

Equilibrium depending on the pH-value sets between hypochlorous acid and hypochlorite ions:

Cl 2 + 2H 2 O → HOCl + H 3 O + + Cl
- (7)
HOCl + H 2 O → H 3 O + + OCl
- (8)

The ratio between these two species of free active chlorine will distribute according to pH as described in figure 1. If the hypochlor ite ions do not inter act with/oxidize material present in the water, it will ultimately fall apart to ch loride ions and oxygen atoms (Equation 9):

OCl
- → Cl
- + O (9)

Hypochlorous acid (HOCl, which is electri cally neutral) and hypochlorite ions (OCl - , electrically negative) will together form free active chlorine. Both substances have very distinctive behaviour. Hypochlorous acid is more reactive a nd is a stronger disinf ectant than hypochlorite. Hypochlorous acid can split into hydrochloric acid (HCl) and atomair oxygen (O). The oxygen atom is also a powerful disinfectant.

The small amounts of free active ch lorine will contribut e to prevent regrowth /biofouling in the
ballast tanks and will thus also to the most exte nt ultimately degrade back into chloride ions. Due to the composition of the EctoSysô electrochemi cal cell, the primary produced chlorine gas will very rapidly, by cathodic interactions and water, form the active chlorine species thus preventing
the formation of harmful chlorinated or ganics such as for example THM:s.MEPC 55/2/4

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I:\MEPC\55\2-4.doc 5.2.4 Chemistry of free active chlorine in sea water

5.2.4.1 Chlorine equilibrium

Free active chlorine express the oxidizing power of a chlorine containing solution as if all the chlorine species present were available as Cl 2 , transformed according to reactions such as those given below:

Cl 2 + H 2 O = HClO +HCl (10)

Cl 2 + 2 OH - → ClO - + Cl - + H 2 O (11)

Chlorine and its entire derive d species are oxidative and very reactive compounds. Chlorine gas is a more efficient oxidiser than hypochlorous acid (HOCl), and hypochlorous acid is more efficient than the hypochlorite ion (ClO - ). The balance between HOCl and ClO - can be studied in polluted water with pH between 4 and 10. In this case, the kinetic of the reactions and the final products obtained depend to a large extent on the percentage of each of the two species (HOCl, ClO - ).

There are three species of chlorine in equilibrium in water: gaseous chlorine Cl 2 , HOCl (also a gas at room temperature and pressure), and ClO - . An example of the distribution between them as a function of pH is shown in figure 1. For example, at pH 7.5 half of the chlorine is active as
HOCl and half is available as ClO - . The pH of sea water is nor mally 8-8.2 and the only species effectively present is ClO -

.

pH 2 4 6 8 10Form in which available chlorine is present (%)

0 20 40 60 80 100

OCl - HOCl

Cl 2

Figure 1: Calculated variation in composition of a chlorine solution with degree of acidity or alkalinity for 0.1 M Cl 2 in water at standard temperature and pressure (the data in this figure are based on general chemistry handbooks).

Hypochlorite (OCl - ), which will be the free active chlorine specie most common in seawater due to a pH on the alkaline side, is an oxidant wh ich oxidizes other substances and thereby reduces itself to chloride ions. However, si nce sea water naturally contains 65ppb Br - , HOCl will normally transform to HOBr (Equation 12) that is th e more stable substan ce in sea water at pH
around 8.MEPC 55/2/4

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I:\MEPC\55\2-4.doc HOCl + Br
- → HOBr + Cl - (12)

Halogenated organic com pounds may be formed by the reactions of hypochlorite with organic substances. The possible reaction products incl ude trihalomethanes, THMs (ultimately in sea water mainly as bromoform) and Haloacetic acids, HAAs formed at low pH. Some of these halogenated compounds may be toxic and slowly degr adable in the aquatic environment, and is a mayor concern for conventional chlorine water treatment processes. For the EctoSysô BWT case, see further section 5.3 a nd also especially section 5.3.2.

5.2.4.2 Main reaction routes

There are mainly four routes for the transfor mation of free active chlorine in sea water:

• Chlorination with amines R-NH 2 or ammonium NH 4 + is very rapid and explains the very fast disappearance of free active ch lorine in for instance waste water. The chlorine atom linked with a nitrogen atom is expressed as combined active chlorine.

R-NH 2 + Cl 2 ! R-NHCl + H + + Cl - (13)

If there is, at one point, a larg e excess of active chlorine over -NH 2 , chloramines like
R-NCl 2 and NCl 3 are formed.

• Oxidation reactions occur with many inor ganic or organic compounds. Thus, for example, ferrous ion can be transformed into ferric ion, orga nic radicals can be transformed through hydrolysis, and C-C bonds can be broken. If there are no nitrogen compounds in the solution, this type of reaction is predominant.

• Chlorination of C atoms from organic molecules is easier for molecules with a shorter carbon skeleton. Three ty pical reactions are: Reaction with phenol giving monochlorophenols; Reaction with molecules containing two carbon atoms : acetaldehyde, acetonitrile, and acetic acid, which are chlorinated on the CH 3 , and give chloroacetaldehydes, chloroacetoni triles and chlo roacetic acids; Reaction with final degradation of the carbon chain giving THMs and especially CHCl 3 (chloroform) in
the case of fresh water but main stable THM in the sea water case is CHBr 3 (bromoform).

Free active chlorine can both be maintained consta ntly in excess, as well as rapidly transform into combined chlorine species depending on th e sea water properties. Both rapid and slow reactions can take place and both oxidation an d carbon or nitrogen chlo rination processes are
found. The main reaction where free active chlorine is transformed is the nitrogen chlorination with the formation of mainly mono chloramines. The chemical degradation of combined active chlorine in this type of scenario takes a few hours. It also produces a number of long chain chlorinated molecules (chlorination of C) but to a lesser extent (only 1 or 2% conversion of the free active chlorine). These molecules only repr esent the start of the chemical degradation process. After a certain time, the remaining AOX part would include volatile compounds such as
chloroform but due to the sea water content of br omide, the final main contribution (after a very long decay period) to the Total Residual Oxid ant (TRO) will be HOBr. See further section 5.6.MEPC 55/2/4

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I:\MEPC\55\2-4.doc 5.2.4.3 Naturally occurring hypochlorite production

Hypochlorite is also produced naturally in vivo for cell defence processes. The natural production of halo-oxo acids is widespread and related to haloperoxidases, which is well documented in the literature. A good overview of bi ohalogenation is given by Neid leman and Geigert (1986) and more recently by Winterton (1997) . Hypochlorite is produced by ch loroperoxidases, which are, among others, produced by mammals (in white blood cells), lichens and in many fungal species (Vollenbroek et al. , 1995). Active chlorine species represen ting chlorine at a formal +I oxidation state (HOCl, Cl 2 , N-chloroamide, etc.) have been quantif ied to some extent in one study looking at the rate of conversion of oxygen into pol ymorphonuclear leukocytes when phagocytozing a micro-organism. It was demonstrated that 28% of the consumed oxygen is converted into active chlorinating agents (Foote et al ., 1983). Even chlorine gas spec ies have been identified in neutrophiles during phagocytosis (Hazen et al., 1996). Hypochlorite and active chlorine species (as well as other oxidants) will thus always be present in natural sea water due to dissolved chloride ions and naturally occurri ng bio reactions and equilibriums.

5.2.5 Analysis of free active chlorine

The analysis methods for free active chlorine approved by the Standard Methods Committee in 1993 (APHA, 1995) for fresh water use iodine, DPD (N,N-diethyl-p-phe nylene-diamine) or syringaldazine. The DPD methods are commonly used for tr eated and waste water using ferrous ammonium sulphate or by colorimetry. Spectro photometric colorimetry was chosen due to its feasibility to on site an alysis. However, with colorimetric methods, organic contaminants and may produce a false free chlorine reading, and sa mple colour and turbidity may interfere. Sea water is not an ideal media due to the high conten t of dissolved ions. It is also very well known that the DPD reagents are highly unselective to the active chlorine species that is to be analysed,
but instead indicates the total amount of oxidants available w ith an oxidizing power above a certain potential. This is especially important to keep in mind when interpreting free active chlorine readings from DPD anal ysis on electrochemically treated waters, because of the vast number of oxidative species that can potentially form during electrolysis. The term ìfree active chlorineî should consequently in the following s ection 5.2.6 rather be interpreted as ìtotal oxidants capable of reacting with DPDî or similarly the commonl y used term ìTotal Residual Oxidantsî (TRO).

5.2.6 Free active chlorine formation duri ng EctoSysô ballast water treatment

The formation of free active chlorine species in the EctoSysô system has been analysed during artificial- and natural sea water treatment (Swe den, 2003-04), as well as during small scale real
case ballast water treatment conditions in Br emerhaven, Germany during 2005. The analysis techniques that have been used are standardi zed colorimetric methods based on well established DPD reagents (see section 5.2.5), and also mo nitored by on-line measurement probes based on electrochemical analysis techni ques (ProMinent). All tests we re performed using EctoSysô systems dimensioned for treatment of 10m 3 /h.

It was shown and verified that the free active ch lorine formation during EctoSysô treatment of natural (and also artificial) sea water was well below drinking water standards (USA/EPA: 4 mg/l free active chlorine) even under worst case cond itions. It was also shown that the free active chlorine formation was, at a fixed flow rate th rough the cell, directly pr oportional to the applied current at relevant current densities. Thus, it is possible to at all times predict the formation of free active chlorine during EctoSysô treatment at specified flow rates and current densities.MEPC 55/2/4

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I:\MEPC\55\2-4.doc DPD respons (as Free Active Chlorine, DPD1),

natural sea water treatment at flow rate 10m3/h

0,00 0,10 0,20 0,30 0,40 0,50 0,60 0,70

0 5 10 15 20

Current (A)DPD respons (ppm) DPD respons (as Free Active Chlorine, DPD1), artificial sea water with different salinitys, treatment at flow rate 10m3/h, current 12A

0,3 0,35 0,4 0,45 0,5 0,55

15 20 25 30 35 40 45

Salinity (PSU)DPD respons (ppm) Figure 2 illustrates the free active chlorine, interms of DPD1 (Dr. Lange) response, during EctoSysô treatment of natural sea water (west co ast of Sweden, 32 PSU) at nominal flow rate. Nominal current density applied for effec tive hydroxyl radical pro duction and sea water
treatment at nominal flow rate in terms of meeting the standard D- 2 criteria is 2.5kA/m 2 , thus generating approximately 0.5 ppm free active chlori ne as by-product to the main production of the Active Substance of hydroxyl radicals. The temperature was 11°C. The pH was measured to 8.1, and thus the free active chlorine was to 80% in the form of OCl - (see figure 1). The worst case scenario includes an applied current density of 4kA/m 2 and thus a predicted free active chlorine formation of below 2 ppm.

Figure 2: DPD 1 response, current dependency Figure 3: DPD 1 response, salinity dependency

Figure 3 illustrates the free active chlorine formation as a function of the salinity of the media. The tests were performed using artificial sea water produced by dissolving appropriate amounts of NaCl (technical quality, Akzo No bel) with tap water. The water was room-tempered with a pH of 7.1. The tests were performed in multiple and figure 3 shows a typical result. The conclusion is that the salinity of the sea water influenc es the by-production of free active chlorine by increasing its current exchange up to salinity le vels of approximately 30PSU. Below this, less
free active chlorine will be formed due to mass tran sport limitations for disso lved chloride ions to reach the reaction zone. With lower salinities (< 30PSU), anodic current efficiencies will instead rise for the production of hydroxyl radicals and oxygen gas.

Figure 4, below, illustrates the free active chlorine (or TRO) formation at nominal applied current
as a function of the flow rate th rough the cell, during small scale re al case ballast water treatment conditions in Bremerhaven, Germany. It was concl uded that the flow rate is a very important parameter in a specified interval, i.e. below the nominal flow rate. At higher flow velocities of the media, the flow rate has less importance for the total concentration of free active chlorine, because the mass transport improvement i nduced by increased turbulence will be counterbalanced by a larger total treated volume.MEPC 55/2/4

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I:\MEPC\55\2-4.doc DPD respons (as Free Active Chlorine, DPD 1)

natural sea water treatment at current 15A

0,0 0,2 0,4 0,6 0,8 1,0 1,2 1,4 1,6

2 4 6 8 10 12

Flow rate (m3/h)DPD response (ppm)

Figure 4: DPD 1 response as a function of treatment flow-rate (nominal 10m 3 /h)

5.2.7 Decay of free active chlorine and TRO in natural waters

It is well known that chlorine-i nduced oxidants in waters with wi de salinity and ammonia ranges are toxic to aquatic organisms and that the toxi city depend upon the persis tence as well as their chemical form (reference 4). In view of l ack of knowledge and modelling difficulty on the
theoretical rates of oxidant disa ppearance in natural waters, mo st studies take an empirical approach in investigating the decay ra tes and products. A model of the HOCl/OCl - has been developed in Appendix II to reference 7.

5.2.7.1 Predictions and models

Studies of the self decomposition (no interactions with organics /inorganics) of hypochlorite in
distilled water without the influe nce of photolysis have been studi ed [4]. It was concluded that this mode of free active chlorine decay can be omitted in calculations of real case scenarios and waters, however the decomposition of hypoc hlorite is accelerated by the presence of hypobromite. The natural presence of ammonia in the water will immediately consume oxidants according to eq.I,

C

R = C 0 - rC N

(I)

where C R is the concentration of free oxidants (mg/l) after initial interactions with ammonia, C 0 is the initial free oxidant concentr ation, r is a weight ratio chlori ne and ammonia content which is estimated to 6.2 in sea water, and C N is the concentration of ammonia nitrogen (mg/l). After this immediate consumption, the further decay can be modelled as a second order reaction [5]:

2 C k dt dC

⋅ =

− (II)

where C is the concentration of free oxidants at time t, and k is the reaction rate constant depending on a number of factors, e.g C 0 . It can thus be conclude d that the decay of total oxidants formed by electrochemical ballast wate r treatment of sea water undergoes one very rapid phase and one decay phase over time. If Cí 0 is defined as Cí 0 = C 0 ñ C R (which also equals

rC N in eq. I), integration of eq. II yields:MEPC 55/2/4

ANNEX Page 19

I:\MEPC\55\2-4.doc '

0 1 1

C t k C +

⋅ = (III)

that gives a theoretical expression of the total ox idant concentration in sea water at time t (min)
after treatment. As an indication of the value of th e constant k at relevant conditions, k has been measured to 0.52 (l/mg*min) at C 0 = 0.84 mg/l free active chlorine dose in natural sea water.

5.2.7.2 Experiments and analysis

The decay of free active chlorine/TRO levels wa s investigated in rele vant natural sea water environment after EctoSysô treatment under simulated BWT conditions in Bremerhaven harbour, Germany. The analysis technique used was the standard DPD method as described above in section 5.2.5. The results clearly show that the free ac tive chlorine content (DPD response) in treated natural sea water rapidly start to drop fr om an initial concentration of 0.55 ppm during the first 20 minutes after treatment. The influence of sun light (photolysis) was prevented by storage of the treated water in a dark container, temperature about 15-20°C. The DPD reading of free active chlorine (or ra ther total oxidant level) as described under section 5.2.4.3 corresponds in this particular case more likely to a disturbance to the spectrophotometric analysis induced by the high tu rbidity of the water. Figure 5 shows the decay
of free active chlorine/TRO down to reach back ground levels (continuously measured and shown as ìEctoSys influentî) after 50 minutes.

DPD response (as Free Active Chlorine, DPD1) decay in natural sea water, stored after EctoSys

treatment

0,10 0,15 0,20 0,25 0,30 0,35 0,40 0,45 0,50 0,55 0,60

0 20 40 60 80

Time (min)DPD response (ppm)

EctoSys effluent

EctoSys influent

Figure 5: Decay of oxidants produced durin g EctoSysô nominal treatment of natural

sea water

The two phases of free oxidant decay (see secti on 5.2.7.1) is clearly shown in this figure. The back-ground ìzeroî level (0.20-0.25 ppm) of fr ee oxidants (in this particular case, where the
treated ballast water is stored under dark conditi ons in accordance with real case ballast water tanks) is reached at approximately 1h after nominal EctoSysô treatment.

5.2.8 Risk characterization and analysis of free act ive chlorine (the Proce dure (G9), section 5.3)

5.2.8.1 Screening for persistence, bioaccumulation and toxicity

The Active Substance of free active chlorine sp ecies produced as a by-product in the EctoSysô disinfection system does not fulfil the PB T criteria as outlined G9 and EC, 2003a:MEPC 55/2/4

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I:\MEPC\55\2-4.doc Criterion PBT criteria P (persistence) Half-life > 60d in marine water or > 40d in fresh water or
half-life > 180d in marine sediment or > 120d in fresh water sediment or readily biodegradable B (bioaccumulation) BCF > 2000 or l gK OW > 4.5 T (toxicity) Chronic NOEC < 0.01 mg/l or CMR or endocrine disruption effects.

Due to the rapid breakdown of all free active chlorine species in na tural waters (section 5.2.7) it is concluded that they are not persistent in the environment. The octanol-water partition coefficient (log K OW, the Procedure (G9), paragraphs 5.3.7 and 5.3.11) for hypochlorite has been calculated to a negative value of -3.42, therefor e bioaccumulation is not an issue for hypochlorite and further testing not considered relevant. The toxicity of chlo rine species have been thoroughly investigated in accordance with the Procedure (G9) , and will in this application be shown not to pose threat to the environment in the case of the small by-production du ring EctoSysô treatment
of ballast water. This statement is based on facts such as the low initial concentrations, the rapid decay (section 5.2.7.1), predicted PEC values of zero (section 5.2.11.2) and low PEC further supported by modelling ballast water dilution af ter discharge in har bours (section 8).

5.2.9 Effect assessment of free act ive chlorine to marine environment

5.2.9.1 General information about the toxicity data

Chlorine and sodium hypochlorite ar e listed for registration as bi ocide by the EuroChlor group of
which Akzo Nobel NV is a member. Both substan ces are currently also under evaluation in the EU Existing Substances Program which evaluate s all uses of the compounds, including biocidal. This activity is co-ordinated by EuroChlor. Co mmon principals of risk assessment apply and need IUCLID data files. As all environmental data for chlorine is based on data already mentioned in the hypochlorite dossier, the EU ch lorine evaluation awaits the completion of hypochlorite. Hypochlorite and chlori ne are both in there final stag es and are expected to be completed soon.

The Akzo Nobel strategy for the Biocidal Produc ts Directive (BPD) is to make use of the
finalized risk assessment and discuss with the authorities what additional work should be performed and in how far is reworking of docum ents for BPD required. The IUCLID data files are scheduled to be updated af ter the EU Risk Assessment Report (RAR) is finished (during 2006) to make this database consistent with RAR.

Therefore, at the moment there is no documentation finalized. The most consistent documentation is the running draft Risk Asse ssment Report on hypochlorite (May 2004) which data included in this proposal refers to. There is a general consensus on the conclusions of the risk assessment. The produced concentrations of free active chlorine in the EctoSys during ballast water management are below drinking water standa rds and will never reach levels dangerous to the environment when discharged. Toxicity evaluations are made under natural sea water environmental conditions (e.g. considering eff ect of sun light, pH, te mperatures etc.).

There is a large amount of documented data av ailable on the aquatic toxicity of hypochlorite, from a number of sources, including general reviews (e.g. Brungs, 1973; Mattice & Zittel, 1976; Kalmaz & Kalmaz, 1981), peer-reviewed literatu re, personal communications and IUCLID (updated version 03/06/94) which is available to the public. The references are only indicated inMEPC 55/2/4

ANNEX Page 21

I:\MEPC\55\2-4.doc the text of this dossier and not listed specifically in the reference list ñ however they are available through the separate Akzo Nobel Risk Assessment Report (ref erence 7) on hypochlorite. IUCLID data have been checked, and incl uded alongside additional data from other references that were obtained from literature. For each study, expe rimental conditions and main results are summarized in tables 3, 4 and 5. As the data available on the aquatic toxicity of hypochlorite have been generated over several decades using different testing methods , species and conditions, they need to be carefully evaluated for validity.

The validity of the aquatic toxicity data was evaluated according to th e criteria recommended by the European authorities and present in IUCLID. The evalua tion criteria are defined as:

- Rated 1 = valid without restriction
- Rated 2 = valid with restriction
- Rated 3 = invalid - Rated 4 = not assignable

The main parameters that need to be documen ted when describing aqua tic toxicity tests for sodium hypochlorite are:

(a) The pH and temperature

The experimental pH and temperatur e have an important role in th e evaluation of aq uatic toxicity data as they determine the ch emical species presen t. In water, the hypochlorite ion is in equilibrium with hypochlorous acid, the ratio of each species being pH and temperature dependent. The amount of hypochlorous acid d ecreases as pH and temperature increase (Hellawell, 1986). At pH 7.0 70% is HOCl whereas at pH 8.0 80% is ClO - when the temperature
is 25 o C (Taylor, 1993). Therefore in freshwater (chara cteristic pH range of 6.5-7.2) the dominant
form is the more toxic HOCl while at estuarine pHís (7.5-8.2) the reverse is true (Gentile et al.

, 1976). At pH values above 4.0, Cl 2 does not exist - hence when au thors have reported that they used chlorine in aquatic toxicity studies conducted at a pH of about pH 7. 0, the chemical species present are a mixture of HOCl and ClO - . Temperature also affect s the equilibrium between hypochlorous acid and hypochlorite, but to a much lesser extent than pH, with the ionization content (pKa) for hypochlorous acid decreasing from 7.75 at 5 o C to 7.63 at 15 o C and 7.54 at

25 o C (Alabaster & Lloyd, 1980). Aqua tic organisms are generally more sensitive to chlorine at higher temperature; an inverse relationship be tween LC50 and temperature was found in fish (Brooks and Seegert, 1977; Sco tt and Middaugh, 1977). It has been demonstrated that a thermal stress combined with exposure to chlorina ted compounds produces a synergetic effect (Thatcher et al. , 1976)

.

(b) The characteristic s of the test media

Some characteristics of the test media may also affect the evaluation of aquatic toxicity data e.g. presence of ammonia and organic compounds, hardness and salinity. In clean aqueous test media the chlorine present is likely to exist as hypochlorous acid/hypochlorit e ion (i.e. detectable as ìfree active chlorineî) decaying rapidly due to reduction reactions and photolysis, e.g. half-life < 2 hours for both hypochlorous acid and the hypochl orite ion (Taylor, 1993). In natural water there will be more interactions with nitrogen and organic compounds so that the hypochlorous acid/hypochlorite ion decays faster and the chlorine presen t is likely to be a mixture of free active chlorine and chloramines (Ewell et al , 1986; Klerks & Fraleigh, 199 1). The products formed
from chlorination of natural water are also a function of salinity. Sin ce sea water typicallyMEPC 55/2/4

ANNEX Page 22

I:\MEPC\55\2-4.doc contains 65 mg/l bromide, bromination rather th an chlorination may predominate as salinity increases (Scott and Middaugh, 1977).

The effect of the hardness of the test media on the aquatic toxicity of sodium hypochlorite has not been systematically studied. Ho wever it is not considered to be substantial as the dissociation of calcium hypochlorite to the hyp ochlorite ion is repor ted as reversible suggesting that the availability of the hypochlorite ion in test media would not be reduced by the presence of calcium ions (Alabaster & Lloyd, 1980).

(c) The measured test concentration

Hypochlorous acid/hypochlorite ion concentrations will under environmental conditions always decay over the duration of the test, by mechanisms shown in section 5.2.4.2. Therefore the initial dosed concentration is not representative of the concentration to which the test organisms have been exposed for the duration of the test. For ex ample Taylor (1993) has shown that the aquatic toxicity of hypochlorite to Ceriodaphnia dubia in a flow-through test was 24h LC50 = 0.006 mg/l compared to 0.048 mg/l in a static test - in the latter case the concentration of hypochlorite was believed to be poorly maintained. In saltwater, measured concentrations are often expressed as Total Residual Oxidant (TRO ) or Chlorine-Produced Oxidant (CPO), which encompass free and combined chlorine as well, but also include other oxidative products such as brominated species).

For data to be considered:

* valid without restriction (i.e. rated 1) the test details should include the use of standard, or well-documented methodology, standard or known species, standard end- points for short and long-term toxicity, flow-through system, informa tion on the pH, temperat ure, dissolved oxygen, number of concentrations, number of animals, dur ation of the test, measured concentrations of the test substance, performance of the control, clear concentration-effect relationship, statistical method used for calculating the endpoint.

* valid with restric tion (i.e. rated 2) the test report should include a description of the methodology, information on the taxonomy of the species, number of concentrations, number of animals, pH, temperature, test duration, oxygen concentration (or the use of a flow-t hrough method such to guarantee its adequate maintenance), measured test concentrations. A se mi -static exposure regime can be considered satisfactory provided that the chemical concentr ation has been adequately maintained and its fluctuations have properly been monitored and taken into account in the calculation of the endpoint.

* invalid (i.e. rated 3) the test methodology is poorly documented or does not include all the major information needed for ëvalid with restrictioní rating, or bad performance of the control(s).

* not assignable (i.e. rated 4) the test details reported are insufficient to give the test any rate.

* supportive information. Examples are tests co nducted under intermittent exposure, where effect are evaluated after a standard period (e.g. 96h) but refer to a much shorter and discontinuous exposure (in the order of minutes for few times a day), or cases when no clearly identified endpoint can be retrieved for short or long-term toxicity (e.g. LC50/NOE C can only be expressedMEPC 55/2/4

ANNEX Page 23

I:\MEPC\55\2-4.doc as ìsmaller thanî or ìgreater than î). These kind of data , although not adequate as such to derive a PNEC, can provide useful indication of toxicity and are retrieved as supportive information.

The valid data for marine organisms have each been used to determine Predicted No Effect Concentrations (PNECs) for the aquatic co mpartment based on the Technical Guidance Document for New & Existing Substances - 1996 (Commission Re gulation 1488/94/EC) (See further 5.2.10).

5.2.9.2 Toxicity data on hypochlorite for brackish- and sea water species

Fish ñ short term toxicity

The short-term toxicity of chlorinated salt wate r has been tested on many estuarine and marine fish species in bioassays conducte d at different exposure regimes, from a single pulse dose of a
few minutes to a continuous 96 ho urs standard exposure. Data va lid for the assessment were retrieved from the papers by Bellanca and Ba iley (1977), Thatcher (1978) and Roberts et al. (1975).

Bellanca and Bailey (1977) evaluated the short-term toxicity of ch lorine to the estuarine fish
Leiostomus xanthurus (ocean spot) in a flow through labora tory experiment, using a continuous
flow serial diluter fed with river water. The authors calculated a 96h-TLm (equivalent to an LC50) = 0.090 mg/l of TRC, which consisted princi pally of free active chlo rine. This data is
rated 1.

Thatcher (1978) conducted many laboratory flow-t hrough bioassays on 8 species of estuarine and marine fish, belonging to different families including salmonidae

, clupeidae and percidae . Since the main purpose of the study was to investigate th e impact of chlorinated effluents from power plants, fish were simultaneously exposed to hypochlorite and to a 5°C thermal stress. The 96 h LC50 ranged from 0.032 mg/l (as TR O), for the most sensitive species ( Oncorhynchus
kisutch ), to 0.167 mg/l ( Gasterosteous aculeatus ). These data were considered relevant for the assessment because heat is usually associated to free active chlorine in power plants effluents, but they were rated 2 because th e authors report that in a previ ous study the addition of thermal stress resulted in a toxicity higher than chlo rine alone and, moreover, LC50 was calculated pooling data from different tests.

Roberts et al. (1975) tested the toxicity of conti nuous exposure of chlorinated river water (salinity 20%o) to three estuarine fish species. The lowest LC50 was calculated for Menidia
menidia : 96 h LC50= 37 μg/l (as TRC). This data was judged ìvalid with restrictionî (2) because Ca(OCl 2 ) was applied as chlorine source and some information on the experimental procedure is lacking.

Middaugh et al. (1977) tested the toxicity of chlorinated brackish pond water to early-life stages
of Morone saxatilis in a flow-through test. Only data rela tive to eggs hatcha bility could be
retrieved

. A rough estimate of the 48 h LC50 = 8 μg/l TRC was calculated by us using the
authorsí raw data relative to percentages of ha tched eggs per test concentration. This data can be used as indicative information of eggs sensitivity

.

Fish ñ long term toxicity

Goodman et al. (1983) developed a method for te sting the early-life stages of Menidia peninsulae, an estuarine fish of the Atherinidae family. They carried out a 28d test startingMEPC 55/2/4

ANNEX Page 24

I:\MEPC\55\2-4.doc with 36 h old eggs, under flow through conditions us ing natural seawater diluted with freshwater to a 20% salinity, and measured the effects of sodium hypochlorite on eggs survival and fry survival and growth. Fry were the most sensit ive stage. The authors calculated a NOEC (fry survival) = 0.04 mg CPO/l (CPO is to be co nsidered analogous to TRC measured by other authors in saline waters), a concentration at which only 5% of fish died. At this concentration no
sublethal effects were evident. The results of this test are considered fully valid (rated 1).

One prolonged field study has been carried out by Liden et al. (1980) on two different estuarine fish species Brevoortia tyrannus and Leiostomus xanthurus exposed to chlorinated condenser cooling effluents for 19 and 20 days, respective ly. All experiments were carried out in long troughs system where discharge waters, at thr ee levels of chlorination, were continuously pumped, with inflow rates maintained at 0.038 l/s to simulate cooling water retention times observed in the plantís discharge canal. Up to the highest concentration (62 μ g/l as TRO) a negligible mortality occurred among B. tyrannus, whereas at all TRO con centrations, the survival
of L. xanthurus was significantly lower than that of co ntrol fish. At the lowest concentration (14 μ g/l) mortality occurred in 26% of animal s but, because of the lack of a clear concentration-effect relationship, no NOEC or EC10 can be calculated or extrapolated.
These data are therefore not usable for assessment.

Invertebrates ñ short term toxicity

The acute toxicity of sodium hypoc hlorite to saltwater invertebrate s has been widely studied with many organisms, including rotifers, mollusks, crus taceans and worms, but data adequate for the assessment are available only for a few classes.

Thatcher (1978) tested seven spec ies, including shrimps, mysids , amphipods and crabs, in flow through apparatus where animals were simultaneously exposed to chlorinate d unfiltered seawater
and 5°C thermal stress to mimic a common scenario in the real environment. The most sensitive species was the shrimp Pandalus goniurus for which a 96 h LC50= 90 μg/l was calculated pooling data from different tests. These data ha ve been rated 2 because of data pooling and, above all, because the additional thermal shoc k might have influenced the sensitivity to hypochlorite.

Very short-term exposure to pu lse chlorination, with and without thermal stress, has been evaluated by Capuzzo and coworkers (1976, 1 979a,b), who conducted flow-through bioassays
with Brachionus plicatilis

, Acartia tonsa , and larvae of Crassostrea virginica with exposure periods of 30-60 minutes at various temperat ures. In bioassays performed at acclimation temperatures, lethality (measured 48 h after exposure) was LC50= 820, 180 and 120 μg/l, respectively. For all species tested, except the copepods, the thermal stress showed a synergistic

effect with residual chlorine concen tration, lowering LC50 values down to 10 μg/l ( ∆ T=7.5°C)

for B. plicatilis and 80 μg/l ( ∆ T=5°C) for C. virginica.

Four invertebrate species were tested by Roberts et al. (1975) using estuarine river water, chlorinated by addition of Ca(OCl) 2 in flow through or static syst ems. When static systems were used the TRC concentrations were kept as stable as possible by constant addition of the chemical and average values were used to calculate the endpoi nts. The lowest lethal concentrations to be used as supportive information are extrapolated values for Mercenaria mercenaria larvae (48 h TL50=1 μg/l TRC , in the static test) and Crassostrea virginica juveniles 96 h EC50 (shell deposition)=23 μg/l TRC , in the flow through test). The au thors report that when oyster larvae were exposed intermittently (manual additions at 6-8h intervals) the 48 h LT50 was 0.11 mg/l, i.e. two orders of magnitude higher.MEPC 55/2/4

ANNEX Page 25

I:\MEPC\55\2-4.doc In later experiments Roberts and Gleeson (1978) observed a similar toxicity in oyster and copepods continuously exposed for 48 hours to Ca (OCl) 2 in flowing estuarine river water. For Crassostrea virginica larvae the 48 h EC50 was 26 μg/l and for adults of Acartia tonsa the
lowest 48 h LC50 was 29 μg/l as residual chlorine measured amperometrically. In the absence of other, more reliable studies wi th the relevant chemical spec ies (sodium hypochlorite) it was decided to use these data in the assessment, b ecause they provide valuable information for the toxicity assessment of chlorinated natural water, and assigned these data the rate ëvalid with
restrictioní because of the different parent compound.

The range of acute toxic ity of chlorinated seawater to invertebrates appears therefore to span almost two orders of magnitude.

Invertebrates ñ long term toxicity

In the scientific lite rature, three studies in vestigating the long-term toxicity of sodium hypochlorite have been found. In a field study on chlorinated condenser cooling effluents using mollusk bivalves (Liden et al. , 1980), the survival of oysters ( Crassostrea virginica ) and clams ( Rangia cuneata ) maintained at three TRO concentrations for 15 days was not affected at concentration as high as 62 μ g/l, while oyster mean shell deposition was significantly reduced in
the treated animals. At the lo west test concentration (14 μ g/l) a 14% reduction in shell deposition was observed, so that following Technical Guidance Documents (TGD) the NOEC can be estimated as LOEC/2, i.e. 7 μ g/l. This data is rated 2 because it was obtained from a non-standard

test.

Scott and Middaugh (1977) examined the lethal and sublethal effects of chlo rine to adult oyster ( Crassostrea virginica ) during seasonal chronic exposures (45-75 days) to incoming estuarine sea water, whose temperature, pH and salinity was naturally fluctuating. Survival was reduced at relatively high concentrations of Chlorine- Pr oduced Oxidants (CPO); a rough estimation of

LC10 ≅ 160 μ g/l CPO was made on the basis of the conc entration-effect curves. On the other hand, severe sublethal effects (mean condition in dex and gonadal index) were observed also at the lowest tested concentration (140 μ g/l CPO), so it is expected that the NOEC for these effects
would be << 140 μ g/l CPO. Because of the lack of a clear endpoint, these data cannot be used in
a risk assessment.

In another experiment Scott et al. (1979) found that mortality of C. virginica was not significantly reduced at 110 μ g/l but the high mortality observed in the control make this result
unreliable. At the same concentration marked sublethal effects were observed, but no direct
concentration-effects relationshi p was found (not valid data).

Algae: Phytoplankton ñ short term toxicity

Data on short-term toxicity to algae were retrieved from the literature but they were not considered adequate for the e ffects assessment of hypochlorite.

The effects of chlorine to three phytoplankt onic algae species we re tested by Videau et al. (1979) in static tests with filtered sea water, aimed to evaluate a number of variables. The most sensitive species was Dunaliella primolecta , for which an initial dose of 400 μ g/l TRO caused 50% mortality in 24 hours. After 3 hours from dosi ng, free active chlorine had disappeared in
chlorinated water below 50 μ g/l. Based on their experimental results, the authors extrapolatedMEPC 55/2/4

ANNEX Page 26

I:\MEPC\55\2-4.doc that in a natural medium, having a population of 1cell/ml, mortality would reach 65% after 24 h exposure at 200 μ g/l.

Gentile et al. (1976) report the Cl 2 concentrations causing 50% gr owth reduction in a series of 24 h static tests on 11 phytoplankton sp ecies; the LC50 ranged from 75 to 330 μ g/l. Only the highly concentrated stock solution was meas ured. Other tests performed on the diatom Thalassiosira pseudonana showed that, 48 h after exposure to 200 μ g/l chlorine, growth was reduced by about 60%.

Algae: Phytoplankton ñ long term toxicity

Sanders et al . (1981) studied the eff ects of prolonged chlorina tion on natural marine phytoplankton communities cultivated in large tanks under flow through conditions (semi-field test). To achieve measurable concentration in the exposure ta nks, HOCl was added by single daily additions directly to the tanks, where it degraded within 2 hours (an intermittent exposure was therefore resulting). A 50% reduction in cell density (the most sensitive endpoint) was observed in the 21 day test at concentrations as low as 1-10 μg/l TRC . These data provide evidence of the severe impact of free chlorine on phytoplankton at very low concentrations, even at intermittent exposure (data us ed as supportive information).

Microcosms ñ long term toxicity

Erickson and Foulk (1980) used outdoor and indoor flow-through syst ems to evaluate the effects of continuous chlorination (1 year) on entraine d estuarine plankton communities consisting of eggs, larvae, algae and juveniles (not better sp ecified). NaOCl was con tinuously applied at dose
levels of 125 to 1441 μ g/l, which resulted in concentrations of residual chlorine in the systems
below the detection limits of th e amperometric analyzer used ( 10 μg/l). In all treatments a reduction of ATP, measured as indication of bi omass, was observed (from 13% to 58%). This data can be used as supportive information.MEPC 55/2/4

ANNEX Page 27

I:\MEPC\55\2-4.doc 5.2.9.3 Summary of ecotoxicology study results with sodium hypochlorite in sea water

Table 3: Toxicity data on fish

Species System Comments Duration Anal. Parameter Results Val Reference

(Short term studies) T°/pH meas. (mg/l)

Alburnus alburnus S 10°C/7.8 96 h (-) LC50 32-37 3 Linden et al. (1979)

Ammodytes hexapterus FT 14.8°C/8.0 96 h (+) TRO LC50 0.082 2 Thatcher (1978)

Clupea harengus FT 14.8°C/8.0 96 h (+) TRO LC50 0.065 2 Thatcher (1978)

Cymatogaster aggregata FT 14.8°C/8.0 96 h (+) TRO LC50 0.071 2 Thatcher (1978)

Cymatogaster aggregata FT 13°C//7.9-8.1 60 min (+)TRO LC50 0.308 3 Stober et al. (1980)

Cymatogaster aggregata FT 20°C//7.9-8.1 60 min (+)TRO LC50 0.230 3 Stober et al. (1980)

Cynoscion nebulosus S 25°C/7.8 48 h (+) TRC LC50 0.17 +/- 0.28 3 Johnson et al. (1977)

Cynoscion nebulosus S 25°C/7.8 48 h (+) TRC Hatch (LC50) 0.21 +/- 0.01 3 Johnson et al. (1977)

Cynoscion nebulosus S 25°C/7.8 48 h (+) TRC Hatch (LC50) 0.21 +/- 0.01 3 Johnson et al. (1977)

Fundulus heteroclitus FT 24°C/7.9-8.1 30 min (+) TRO 100% mortality
at 48h 0.65 3 Capuzzo et al. (1977)

Gasterosteus aculeatus FT 14.8°C/8.0 96 h (+) TRO LC50 0.167 2 Thatcher (1978)

Menidia menidia FT 17-28/river water 96h (+) TRC TL50 0.037 2 Roberts et al. (1975)

Morone saxatilis FT 18°C/6.8 ---- (+) TRC incipient LC50 0.04 3 Middaugh et al. (1977)

Morone saxatilis FT 18°C/6.8 ---- (+) TRC incipient LC50 0.07 3 Middaugh et al. (1977)

Morone saxatilis FT 18°C/6.8 ---- (+) TRC incipient LC50 0.04 3 Middaugh et al. (1977)

Morone saxatilis FT 18°C/6.8 48 h (+) TRC LC50 * 0.008 s Middaugh et al. (1977)

Mugil cephalus ----- >48h (-) TLM50 8.0 3 Parella et al. (1986)

Oncorhynchus gorbuscha FT 14.8°C/8.0 96 h (+) TRO LC50 0.052<x<0.023 3 Thatcher (1978)

Oncorhynchus gorbuscha FT 18.6-23.5°C/7.53 7.5-60 min (+)Cl2 24h LC50 0.5-0.1 3 Stober et Hanson (1974)

Oncorhynchus kisutch FT 14.8°C/8.0 96 h (+) TRO LC50 0.032 2 Thatcher (1978)

Oncorhynchus kisutch FT 13°C//7.9-8.1 60 min (+)TRO LC50 0.208 3 Stober et al. (1980)

Oncorhynchus kisutch FT 20°C//7.9-8.1 60 min (+)TRO LC50 0.130 3 Stober et al. (1980)

Oncorhynchus tshawytscha FT 14.8°C/8.0 96 h (+) TRO LC50 0.065<x>0.038 3 Thatcher (1978)

Oncorhynchus tshawytscha FT 11.7-21.7°C/7.2-7.8 7.5-60 min (+)Cl2 24h LC50 0.5-0.005 3 Stober et Hanson (1974)

Parophrys vetulus FT 14.8°C/8.0 96 h (+) TRO LC50 0.073 2 Thatcher (1978) Pseudopleuronectes
americanus FT 24°C/7.9-8.1 30 min (+) TRO 100% mortality
at 48h 0.55 3 Capuzzo et al. (1977)

Stenotomus versicolor FT 24°C/7.9-8.1 30 min (+) TRO 100% mortality
at 48h 0.65 3 Capuzzo et al. (1977)

Leiostomus xanthurus

FT 14.2-16°C/7,5 96h (+)TRC TLm(=LC50) 0.09 1 Bellanca & Bailey (1977)

Species System Comments Duration Anal. Parameter Results Val Reference

(Long term studies) T°/pH meas. (mg/l)

Brevoortia tyrannus FT 31.2°C/7.1 19 d (+) TRO 0% mortality 0.062 s Liden et al. (1980)

Leiostomus xanthurus FT 31.2°C/7.1 20 d (+) TRO 26% mortality 0.014 s Liden et al. (1980)

Menidia peninsulae FT 25°C/7.9-8.0 28d (+) CPO NOEC 0,04 1 Goodman et al. (1983)

Validity System Analytical measurement

1 = valid without restriction S = Static TRO = total residual oxidant
2 = valid with restriction SS = Semi static TRC = total residual chlorine 3 = invalid FT = flow-through Cl 2 = available chlorine 4 = not assignable DA = daily chemical addition s = supportive

* calculated using raw data provided by the authors

(a) the time is that when the effect has been measured, in those cases when it does not coincide with the duration of exposure.MEPC 55/2/4

ANNEX Page 28

I:\MEPC\55\2-4.doc Table 4: Toxicity data on invertebrates

Species System Comments Duration Anal. Parameter Results Val Reference

(Short term studies) T°/pH meas. (mg/l)

Crassostrea virginica (MB) FT 17-28/river water 96h (+) TRC EC50 0.023 (b) s Roberts et al. (1975)

Crassostrea virginica (MB) S, CA 17-28/river water 48h (+) TRC TL50 <0.005 s Roberts et al. (1975)

Mercenaria mercenaria (MB) S, CA 17-28/river water 48h (+) TRC TL50 0.001 (b) s Roberts et al. (1975)

Acartia tonsa (CCP) S, CA 17-28/river water 48h (+) TRC TL50 <0.005 s Roberts et al. (1975)

Acartia tonsa (CCP) FT 20/25°C/+ 48h (+) Cl2 LC50 0.029/0.067 2 Robert and Gleeson (1978)

Crassostrea virginica (MB) FT 20/25°C/+ 48h (+) Cl2 EC50 0,026 2 Robert and Gleeson (1978)

Crassostrea virginica (MB) FT 20°/25°C//7.9-8.1 30 min (+)TRO 48h LC50 0.08-0.12 s Capuzzo (1979a)

Crassostrea virginica (MB) FT 20°/25°C//7.9-8.1 30 min (+)TRO 48h LC100 0.86-1.40 s Capuzzo (1979a)

Crassostrea virginica (MB) FT 48h (+)CPO LC50 0.027 4 Roberts (1980)

Mulina lateralis(MB) FT 48h (+)CPO LC50 0.038 4 Roberts (1980)

Brachionus calyciflorus (R) S 25°C/7.5 24 h (-) LC50 0.37 3 Snell (1991)

Brachionus plicatilis (R) FT 20°/25°/27.5°C/7.9-8.1 30 min (+) TRO LC50 0.01-0.18 s Capuzzo (1979b)

Brachionus plicatilis (R) FT 20°/25°/27.5°C/7.9-8.1 30 min (+) TRO LC100 0.46-1.76 s Capuzzo (1979b)

Crangon nigricauda (CD) FT 14.8°C/8.0 96 h (+) TRO LC50 0.134 2 Thatcher (1978) Crangon septemspinosis(CD) S 10°C/8.4 5min (+) 24h TL50 10 3 Gentile et al. (1976)

Hemigramus nudus (CD) FT 14.8°C/8.0 96 h (+) TRO LC50 1.418 2 Thatcher (1978) Hemigrammus oregonensis (CD) FT 14.8°C/8.0 96 h (+) TRO LC50 1.418 2 Thatcher (1978)

Pandalus danae (CD) FT 14.8°C/8.0 96 h (+) TRO LC50 0.178 2 Thatcher (1978)

Palaemonetes pugio (CD) S 22°C/8.3-8.7 96 h (+) LC50 52 (c) 3 Curtis and Ward(1981)

Homarus americanus (CD) FT 60 min (+) TRC 48h LC50 0.41-2.89 s Capuzzo (1976)

Neomysis sp. (CD) FT 14.8°C/8.0 96 h (+) TRO LC50 0.162 2 Thatcher (1978)

Pandalus goniurus (CD) FT 14.8°C/8.0 96 h (+) TRO LC50 0.090 2 Thatcher (1978)

Anonyx sp. (CA) FT 14.8°C/8.0 96 h (+) TRO LC50 0.145 2 Thatcher (1978)

Pontogenia sp. (CA) FT 14.8°C/8.0 96 h (+) TRO LC50 0.687 2 Thatcher (1978)

Gammarus fasciatus (CA) S 20°C/7.5 96 h (-) LC50 4.0 3 Ewell (1986)

Asella intermedius (CA) S 20°C/7.5 96 h (-) LC50 32 3 Ewell (1986)

Nitocra spinipes (CCP) SS 10°C/7.8 96 h (-) LC50 40 3 Bengtsson (1983)

Nitocra spinipes (CCP) S 10°C/7.8 96 h (-) LC50 40 3 Linden (1979)

Acartia tonsa (CCP) FT 10°/15°/20°/25°/28°C/8.0 30 min (+) TRO 48h LC50 0.82-0.86 s Capuzzo (1979)a

Acartia tonsa (CCP) FT 10°/15°/20°/25°/28°C/8.0 30 min (+) TRO 48h LC100 3.5-3.6 s Capuzzo (1979)a

Acartia tonsa(CCP) S 15°C/--- 120min ? 24h 50% mortality 1 3 Gentile et al. (1976)

Eurytemora affinis(CCP) S 15°C/--- 360 min ? 24h 50% mortality 1 3 Gentile et al. (1976) Pseudodiaptomus coronatus(CCP) S 15°C/--- 9 min ? 24h 50% mortality 2.5 3 Gentile et al. (1976)

Arcatia tonsa (CCP) FT 31°C 24 h (+) TRO mortality > 0.085 3 Liden (1980)

Perna viridis FT 28,9-29,4°C/#8,0 30h Cl2 100% Killed 10 2 Rajagopal et al. (1995)

Perna viridis FT 28,9-29,4°C/#8,0 48h Cl2 100% Killed 10 2 Rajagopal et al. (1995)MEPC 55/2/4

ANNEX Page 29

I:\MEPC\55\2-4.doc Species System Comments Duration Anal. Parameter Results Val Reference

(Long term studies) T°/pH meas. (mg/l)

Crassostrea virginica (MB) FT 24-31°C/--- 60 d (+) TRC 63% effect 0,11 3 Scott et al. (1979)

Crassostrea virginica (MB) FT 24-31°C/--- 60 d (+) TRC NOEC mortality 0,11 3 Scott et al. (1979)

Crassostrea virginica (MB) FT (field) 31.2 °C/7.1 15 d (+) TRO 14% effect 0,014 2 Liden et al. (1980)

Brachidontes striatulus FT 29,2-29,8°C/#8,0 20d Cl2 100% killed 1 2 Rajagopal et al. (1997)

Brachidontes striatulus FT 29,2-29,8°C/#8,0 24d Cl2 100%Killed 1 2 Rajagopal et al. (1997)

Brachidontes striatulus FT 29,2-29,8°C/#8,0 102h Cl2 100%Killed 5 2 Rajagopal et al. (1997)

Brachidontes striatulus FT 29,2-29,8°C/#8,0 156h Cl2 100%Killed 5 2 Rajagopal et al. (1997)

Perna viridis FT 28,9-29,4°C/#8,0 21d Cl2 100% Killed 1 2 Rajagopal et al. (1995)

Perna viridis FT 28,9-29,4°C/#8,0 33d Cl2 100% Killed 1 2 Rajagopal et al. (1995)

Crassostrea virginica (MB) FT 11-27°C/7.4-8.3 45-75 d (+) CPO 0.160-0.250 3 Scott and Middaugh (1977)

Crassostrea virginica (MB) FT 11-27°C/7.4-8.3 45-75 d (+) CPO NOEC <<0.140 3 Scott and Middaugh (1977)

Rangia cuneata (MB) FT (field) 31.2 °C/7.1 15 d 0% effect 0.062 3 Liden et al. (1980)

Validity System Analytical measurement
1 = valid without restriction S = Static TRO = total residual oxidant 2 = valid with restriction S, CA = static with cons tant addition system TRC = total residual chlorine 3 = invalid SS = Semi static CPO = chlorine-produced oxidant 4 = not assignable FT = flow-through Cl 2 = available chlorine s = supportive

Species MB = Mollusc bivalve; MG = Mollusc gasteropod; R = Rotifer; CD = Crustacea decapod; CA = Crustacea amphipod; CPP = Crustacea co pepod;
CCL = Crustacea cladocere

(a) the time is that when the effect has been measured, in those cases when it does not coincide with the duration of exposure (b) extrapolated value (c) 4-6% aqueous solution (d) rough estimate on raw dataMEPC 55/2/4

ANNEX Page 30

I:\MEPC\55\2-4.doc Table 5: Toxicity data on algae

Species System Comments Duration Anal. Parameter Results Val Reference

(Short term studies) T°/pH Meas. (mg/l)

Dunaliella primolecta S 20°C 24 h (+)TRO 50% mortality 0.4 3 Videau et al. (1978.79)

Pavlova lutheri S 20°C 24 h (+)TRO 50% mortality 4 3 Videau et al. (1978.79) Phaeodactylum

tricornutum S 20°C 24 h (+)TRO 100% mortality 0.8 3 Videau et al. (1978.79)

Skeletonema costatum S 20°C 24 h (+) (a) LC50 0.095 3 Gentile et al. (1976)

Rhodomonas baltica S 20°C 24 h (+) (a) LC50 0.11 3 Gentile (1976)

Dunaliella tertiolecta S 20°C 24 h (+) (a) LC50 0.11 3 Gentile (1976)

Monochrysis lutheri S 20°C 24 h (+) (a) LC50 0.200 3 Gentile (1976)

Thalassiosira pseudonana S 20°C 24 h (+) (a) LC50 0.075 3 Gentile (1976)

Thalassiosira pseudonana S 20 min 60% effect at 48h 0,2 3 Gentile (1976)

Chaetoceros decipiens S 10°C 24h (+) (a) LC50 0.140 3 Gentile (1976)

Thalassiora nordensholdii S 10°C 24h (+) (a) LC50 0.195 3 Gentile (1976)

Thalassiosira rotula S 10°C 24h (+) (a) LC50 0.330 3 Gentile (1976)

Asterionella japonica S 10°C 24h (+) (a) LC50 0.250 3 Gentile (1976)

Chaetoceros didyum S 10°C 24h (+) (a) LC50 0.125 3 Gentile (1976)

Detonula confervacea S 10°C 24h (+) (a) LC50 0.200 3 Gentile (1976)

Phytoplankton FT 9-18°C//8.4 12h (+)TRO Primary productivity(EC98) 1.2 3 Carpenter (1972)

Phytoplankton SS 7-19.7°C//8.4 3x1.5h (+)TRO Primary productivity(EC86) 1.2 3 Carpenter (1972)

Species System Comments Duration Anal. Parameter Results Val Reference

(Long term studies) T°/pH Meas. (mg/l) Phytoplankton (microcosm) FT, DA 6-8°C/7.7-7.9 21 d (+)TRC (b) 50% cell density
reduction 0.001-0.01 s Sanders et al. (1981)

Microcosm study FT 10.1- 30.8 °C/ 1 y (+)TRC 13-58% ATP
reduction < 0.01 s Ericksson and Foulk (1980)

Validity System Analytical measurement

1 = valid without restriction S = Stat ic TRO = total residual oxidant
2 = valid with restriction SS = Semi static TRC = total residual chlorine 3 = invalid FT = flow-through Cl2 = available chlorine 4 = not assignable DA = daily chemical addition s = supportive

(a) only the stock solution (100 mg/l) was measured (b) free active chlorine as HOCL was administeredMEPC 55/2/4

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I:\MEPC\55\2-4.doc 5.2.9.4 Summary of Ecotoxicity Data Selected for the Determination of the PNEC for Brackish and Sea Water Organisms

The valid and supporting data discussed in sections 5.2.9.3 to 5.2.9.4, which are acceptable for use in the determination of the PNEC for brackish and sea water organisms, are collected and
summarized in table 6.

Table 6: Summary of ecotoxicity data sele cted for the determination of the PNEC for brackish and sea water organism.

SHORT-TERM TOXICITY

Valid data Supportive information

Endpoint Study
Details/Reference Endpoint Study
Details/Reference

Fish 96hLC50 = 32 μg TRO/l (rated 2) Thatcher, 1978 48hEC50 =

8 μ g TRC/l (eggs) Middaugh et al., 1977 Fish 96hLC50 = 90 μg TRC/l (rated 1) Bellanca and Bailey, 1977
Crustaceans - - - - Mollusks 48h EC50 = 26 μg TRC/l (rated 2) Roberts and Glason, 1978 Algae - - - - LONG TERM TOXICITY

Endpoint Study
Details/Reference Endpoint Study
Details/Reference

Fish 28d NOEC = 40 μg CPO /l (rated 1) (fry survival) Goodman et al.,

1983
Crustaceans - - - - Mollusks 15d NOEC = 7 μg TRO/l (rated 2) (shell deposit) Liden et al., 1980 Algae - 21d EC50 = 1-

10 μ g TRC/l (periphytic community,
intermittent exposure) Sanders et al., 1981

Phyto and Zooplankton - 1y EC50

< 10 μ g TRC/l (biomass reduction) (microcosm study) Erickson and Foulk,

1980

TRO =Total residual oxidant
TRC= total residual chlorine CPO = Chlorine-produced oxidants

Validity rates:
1= valid
2= valid with restriction s= supportive informationMEPC 55/2/4

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I:\MEPC\55\2-4.doc 5.2.9.5 Terrestrial compartment

The possible exposure routes of so ils to free active chlo rine are via contaminated sludges or via direct application of chlorinated water. OCl - / HOCl are highly soluble molecules not likely to sorb onto activated sludges. Therefore, there is no evidence that free active chlorine species have the potential to contaminate activat ed sludges. As a consequence al so, contamination of soils due to dumping of with free active chlorine polluted sludges can be excluded.

Contamination of soils due to direct application of chlorinated water will not be of permanent origin. The high content of organic matter in a soil will allow a quick (order of seconds)
reduction of OCl - / HOCl.

5.2.10 Conclusion and PNEC determination

5.2.10.1 General consensus

In the scientific l iterature of the last 30 y ears, a great number of s hort and long term aquatic toxicity studies on hypochlorite, co nducted with fresh and saltwater organisms belonging to all trophic levels, have been found. Section 5.2.9.4 gives, for each study, details on experimental
conditions and test results are reported for fish, invertebrate s, algae and microorganisms. Nevertheless, after their evaluation following the criteria indicated in the European Commission TGD, the number of valid data judged adequate for risk assessment was drastically reduced because many of them did not meet the validity crit eria specified at the beginning of this chapter. In spite of the high number of studies conducted, only a few provide reliab le information useful
for the assessment. This is because most of the studies were carried out in the 70ís and 80ís and were tailored to answer specific questions such as, for example the efficacy of sodium hypochlorite as biofouling agent, th e effect of temperature stress and/or of intermittent exposure of very short pulse additions of hypochlorite. Hen ce, their evaluation is no t straightforward. From many of these studies, although goo d and reliable, it was not possi ble to retrieve the proper endpoint requested for derivation of PNEC (e.g. the NOEC for long-term studies), so that, following the TGD indications, they were used as additional information in support of valid toxicity data (rated 1 or 2) used in the PNEC calculation. In addition, it shou ld be noted that none of the evaluated experiments were conducted in GLP, due to the fact that most of them were carried out long before the requirements of the Directive 87/ 18/EEC. Short and long term toxicity data are available for microorganisms, al gae, invertebrates and fish. Th e evaluation and comparison of toxicity data are made difficult by the complexity of sodium hypoc hlorite chemistry in water and by the different analytical methods used to meas ure its concentration. To tal Residual Chlorine, TRC, is a measure of both free active and combined active chlorine (such as chloramines). It is difficult to separate the contribution to toxicity of the free available chlorine such as HOCl/ - OCl from that of the combined chlorine species. Also , the relative amounts of the different chlorine species will be different for each test, due to pH and other medium related effects, test duration and ammonium level effects, etc. For those studies where the percentage of free active chlorine (FAC) out of the TRC had been measured and reported the toxic ity endpoints have also been expressed as concentration of FA C/l. In chlorinated salt water, toxicant concentration is often expressed as Total Residual Oxidant (TRO) or Chlorine Produced Oxidants (CPO), which include, in addition to free end co mbined chlorine, also other oxi dative products. This makes the assessment task and the comparability of fresh and salt water toxicity data harder. Ballast water represents waters with high sa linity ranges. In the following the results for sea water are summarized and attempt to derive the PNEC for this environment.MEPC 55/2/4

ANNEX Page 33

I:\MEPC\55\2-4.doc In table 6, toxicity data adequate for risk as sessment have been liste d together with supportive data. Valid short-term toxicity data have been collected for mollusks and fish, which show a similar sensitivity: 48 h EC50 = 26 μ g TRC/l and 96 h LC50 = 32 μ g TRO/l, respectively. Supportive information indicates that acute toxi city is higher for fish eggs: 48 h EC50 = 8 μ g TRC/l. No data for crustaceans or algae are availabl e, so that it is not po ssible to determine which trophic level is the most sens itive in short-term tests.

For the same groups, molluscs and fish, long-term t oxicity data have also been found. Molluscs (15d NOEC = 7 μ g TRO/l) are more sensitive than fish fry (28d NOEC (fry survival) = 40 μ g CPO/l) For crustaceans and algae, adequate data for risk assessment are again not available. Anyhow a study conducted on periphytic community under intermittent exposure provides a 21d EC50 lying between 1 and 10 μ g TRC/l, suggesting that fo llowing continuous exposure the NOEC for algae is likely to be lower than that.

5.2.10.2 PNEC derivation

Considering the specific mode of action of hypochlorite, which is a strong oxidizer, and the recommendations given in the EC technica l guidance documents (TGD) (final version May 2002), short- and long-term toxicity data for saltwater organisms have been pooled. In this way a set of three valid NOEC values is obtaine d, one for each trophic level: fish, molluscs and algae.

When, after pooling the data from fresh and salt water the dataset consists of two long-term NOECs representing two trophic levels (e.g. alg ae and fish) plus a NOEC from an additional marine taxonomic group (e.g. molluscs), as it is the case in the present assessment, the TGD

recommends that a factor of 50 is a pplied to the lowest figure. Hence, PNEC = 3 μ g TRC/l/50 =

0.06 μ g TRC/l corresponding to 2.1 μ g FAC/l/50 = 0.04 μ g FAC/l.

5.2.11 PEC values of active chlorine species due to BWT

A general PEC derivation for active chlorine/TRO in the case of ballast water discharge is not possible to calculate, because of the vast amou nt of possible scenarios and different physical conditions of the harbours, waters, ships etc. PEC local values would have to be predicted in each particular case. However, the most relevant a nd comparable case to ballast water discharge (in terms of discharge concentrations found in the lit erature is regular coolin g water discharge from coastal power plants. The cooling water is taken fr om the sea, chlorinated due to e.g. biofouling of the condensers etc., and discharg ed back directly to the sea. Th e free active chlorine level will be in the same range as the maximum result fr om by-production using EctoSysô in ballast water treatment. The power plant cooling water case has been extensively st udied due to the large volumes of water and due to the limited receiving local area.

Quite recently, some data on TRO concentrations in the discharge plumes in sea water of various power stations have been published (Jenner et al , 1997). These data vary from 0.02 mg/l TRO in the near vicinity of power stations to zero at furt her distances. Moreover it must be noted, that these data most likely do not repr esent hypochlorite but a variety of other oxidants. In general,
observed concentrations will be variable and to a large extent influenced by local conditions. Local regulations are usually designe d to prevent acute effects in the vicinity of the discharges.MEPC 55/2/4

ANNEX Page 34

I:\MEPC\55\2-4.doc Therefore a PEC value for hypochlorite in a worst-c ase regular cooling water scenario will rapidly drop to zero wh en reaching surface water. This can be expected based on the model calculations for the comprehensive household/ sewage scenario predicted by Akzo Nobel (reference 7) and is also supported by measuremen ts (Jenner et al., 1997, 1998). It means that potential effects - if any - may only be expected in the near vicinity of the outlet of the cooling water system and thus not even at all relevant in the ballast wate r discharge case where the exact point of discharge will vary.

The calculation model presented in section 5.2. 7.1 and discharge/decay model (appendix 2 to reference 7) for the sewage exposure scenario cl early show that concentr ations of 0.5 mg/l TRO (maximum value at the power pl ant cooling water condensers, worst-case regular scenario) as well as concentrations up to 8 mg/l (extreme worst-case shock dosing regime) will fall below the detection limit within seconds upon reaching the surface wa ter. Thus, this will certainly also be the case for discharge of treate d ballast water containing < 2 mg/l TRO and can easily be verified during on-board installation and test phase.

5.2.12 Free active chlorine PEC/PNEC derivation

The normal approach to risk assessment consider s the ratio PEC/PNEC as an important factor. This ratio normally includes safety factors of 50-100. However, in this case where PEC is predicted to rapidly drop to zero when reaching surface water, the PEC/PNEC is not relevant to
estimate.

5.2.13 Discharge exposure model

Modelling of the decay and exposure of free active chlorine in sewer and river water have been performed by Akzo Nobel (reference 7). It was concluded that dilution from low (< 10 ppm) concentrations to background levels will occur with in seconds in all relevant, natural cases when the chlorinated waters are discharged. This im plies for the EctoSysô ballast water discharge case a dilution period also will be very short. See further section 7.

5.2.14 Mammalian toxicity (the Pro cedures (G9), paragraph 4.2.1.2)

The worst-case maximum concentration (2 ppm) in EctoSysô ballast water effluents motivates no studies on mammalian toxicity, taking into acc ount the rapid decay (sec tion 5.2.7) of FAC and TRO in natural waters. However, such data on FAC is included in the Akzo Nobel Risk Assessment Report [7] readily available.

5.3 Secondary disinfection by-products

5.3.1 General

Disinfection by-products (DBP:s) are chemical (organ ic and inorganic) subs tances that can form when disinfectants, such as e.g. free active ch lorine, react with natura lly present compounds in the water. The formation of these products main ly takes place during reactions in which organic substances play a major part. These materials end up in water during th e decomposition of plant and animal matter. Little general information can be given on the chemical structures of all kinds of organic substances pr esent in marine sea water and thus being precursors for the formation of possible disinfection by-products during disinfection of ballast water. The mechanisms of
formation of DBP:s therefore remains unclear a nd impossible to generalize. Research is alsoMEPC 55/2/4

ANNEX Page 35

I:\MEPC\55\2-4.doc difficult because of the extensive number of substances that ma ke up organic matter. For this reasons, methods for disinfection of natural wa ters must be carefully evaluated through
effect assessment.

The types of DBP:s that are formed depe nd on a number of influencial factors:

• the type of disinfectant

• the disinfection dose

• the disinfection residuals

When the dose and residuals of the disinfectan t are higher, more disi nfection by-products are
formed.

• circumstances of disinfection: temperature and pH

When temperatures increase, reactions take place faster and causing a higher chlorine
concentration in conventional chlori ne electrolysis to be required for a proper disinfection. This causes more halogenic disinfection byproducts to form. At higher pH values, more THM (Trihalomethanes ñ see below) is also formed from conventional chlorine electrolysis, whereas more haloacetic acids (HAA) are formed when pH values are lowe r (in fresh water applications).

• the constituents of water

• concentrations and properties of naturally present organic matter in the water

The level of organic matter is usually registered as the ìtotal organic carbonî (TOC) concentration or the ìdissolved organic car bonî (DOC) concentration. The composition and concentration of naturally pres ent organic matter determine the types and concentrations of DBP:s that will eventually be formed. Location and seasons may influence the naturally present organic carbon concentration, causing the concentra tions of DBP:s to vary. The formed concentrations of disinfection by-products in lito ral and pelagial water may also be different (reference 11).

Adsorbable Organic halogens (AOX) is a measure of the number of C-Cl bonds formed in a reaction, expressed as Cl 2 consumed to form these bonds. Pa rt of the AOX content is volatile; the main representative in this case is chloroform. It is very important to distinguish between the volatile and the non-volatile part in order to analyse the AOX. The non-volatile part is of high importance due to the potential st ability of some of the compone nts (mainly the chloroacetic and chloroaromatic compounds).

Trihalomethanes (THM) are a group of (mainly) four chemic als that are formed along with other disinfection by-products when chlorine or othe r disinfectants used to control microbial contaminants in water react with naturally occurring organic and inorganic matter. The trihalomethanes are: chloroform, bromodic hloromethane, dibromochloromethane and bromoform. In the case of drinking water, different regulations are currently active internationally. For example, EPA has published the Stage 1 Disinfectants/Disinfection Byproducts Rule to regulate total trihalomethanes (TTHM) at a maximum allowable annual average level of 80 ppb (parts per billion). This standard replaced the current standard of a maximum allowable annual average level of 100 parts per billion in December 2001 for large surface water public water systems. The standard became effective for the first time in
December 2003 for small surface water and a ll ground water systems. The drinking water regulation is mentioned here to serve as comparative value in th e complete risk assessment ofMEPC 55/2/4

ANNEX Page 36

I:\MEPC\55\2-4.doc by-products formation in ballast water treatment using EctoSysô as a disinfecting step, knowing the worst case concentrations of THM produced.

Bromate (BrO 3 - ) is a chemical that is mainly formed wh en ozone used for disi nfection reacts with naturally occurring bromide found in source wate r. Bromate is well known to be carcinogenic
and must be controlled at all sea water trea tment with oxidative methods. The Stage 1
Disinfectants/Disinfection Byproducts Rule regulates bromate at an annual average of 10 ppb in the case of drinking water.

5.3.2 Secondary disinfection by-products in th e EctoSysô ballast wa ter treatment process

The problems with disinfection by-products associat ed with conventional di sinfection techniques can effectively be avoided using the EctoSysô treatment technique. The reactive intermediates producing by-products are degraded cathodically before they form stable and possibly harmful by-products.

THM can (in natural waters) be used as an indi cator of the total amounts of formed disinfection by-products. The formation of HAA is in the Ecto Sysô case not considered relevant because of the low levels of chlorine that are formed (< 2 ppm) combined with th e high pH of sea water. However, several analyses of both THM levels and AOX (Absorbable Orga nic Halogens) levels have been performed during nominal EctoSysô treatment conditions, and also taking a ìworst caseî approach, at different locations and waters . The results show that the THM levels are well under EPA drinking water standards even at ìworst caseî (i.e. low flow rate, very high current). The dominant THM species formed is bromoform due to its relative stability and the sea water
content of bromide. Table 7 summarizes some typical data for THM a nd AOX formation in sea water due to EctoSysô treatment. The THM an alysis were made at a laboratory accredited according to DIN ISO / EC 17025, using method : DIN EN ISO 10301 (F4). AOX was measured according to EN 1485. The analyses were performed approximately 24 h after treatment, thus the total residual chlorine (TRC) a nd free active chlorine (FAC) levels are totally decomposed.

Table 7: Summary of AOX and THM formation in sea water

during EctoSysô treatment with different currents applied

control 2.2A 8A 15A

AOX (ppm) 0.06 0.2 0.2 0.2

THM (ppb):

CHCl 3 < 5 < 5 < 5 < 5
CHCl 2 Br < 5 < 5 < 5 < 5
CHClBr 2 < 5 < 5 < 5 < 5

CHBr 3 < 5 39 42 71

TRC (ppm) < 0.05 < 0.05 < 0.05 < 0.05

FAC (ppm) < 0.05 < 0.05 < 0.05 < 0.05

Figure 6 illustrates the typical in fluence of flow rate to the formation of THM under EctoSysô nominal applied current and natural sea water treatment in Bremerhaven harbour (salinity 11-20 PSU), Germany. It can be concluded that the formation of total THM is negligible at nominal parameters and also in the order of drinking water standards (EPA) at worst case
conditions. The TTHM consisted of bromoform to 85-100% in all cases. In combination with other measurements (see section 5.2.6) of the formation of free active chlorine, it can also be concluded that, using EctoSysô treatment, the fr ee active chlorine (DPD measured ìTROî) levelMEPC 55/2/4

ANNEX Page 37

I:\MEPC\55\2-4.doc can be in the order of 0.6-0.8 ppm without producing THM leve ls that would pose any threat to
the environment.

THM formation in sea water after EctoSys treatment, nominal +

worst-case conditions

0 20 40 60 80 100 120 140

0 20 40 60 80 100 120

Flow rate, % of nominal (=10m3/h)Total THM, ppb

July tests, nominal current, turbidity

12FNU

November tests, worst case current, turbidity 122FNU

Figure 6: THM concentration as a function of flow rate, nomi nal- and worst-case current

(THM analysis by lab accredited according to DIN ISO / EC 17025, method: DIN EN ISO 10301 (F4))

5.3.3 PNEC secondary disinfection by-products

Trihalomethanes

In most fresh water situations the dominant trihalomethane produced during hypochlorite use is chloroform: only in high bromide situations, such as chlorination of sea-water used for cooling, do the brominated trihalomethanes become major components.

It is beyond the scope of this risk assess ment to derive PNECs for the brominated trihalomethanes individually. However, ecoto xicological data (gathered by e.g. Khalanski et al. )
in connection with assessment of seawater chlo rination suggest that th e ecotoxicities of the brominated THMs are not markedly different fro m chloroform. Table 8 below highlights some published studies with useful comparative data:MEPC 55/2/4

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I:\MEPC\55\2-4.doc Table 8: Examples of ecotoxicologica l data for THM:s, aquatic species

Species, biological stage Compound Toxicity mg/l Reference

Daphnia magna (Freshwater) Chloroform
Bromoform 48 hr LC50 = 29
48 hr LC50 = 46 Le Blanc 1980

Lepomis
macrochirus (Freshwater) Chloroform
Bromoform 96 hr LC50 = 13 ñ 22
96 hr LC50 = 29 Anderson & Lusty 1980
Buccafusco et al. 1980

Cyprinus carpio (Carp embryos) Chloroform

BDCM
DBCM
Bromoform 96 hr LC50 = 161
96 hr LC50 = 119
96 hr LC50 = 53
96 hr LC50 = 76 Trebalka et al. 1981

Cyprinus carpio (Carp embryos) Chloroform

BDCM
DBCM
Bromoform 96 hr LC50 = 97
96 hr LC50 = 67
96 hr LC50 = 34
96 hr LC50 = 52 Mattice et al. 1981

In view of the above, it seems reasonable for th e purposes of a broad assessment to regard the trihalomethanes as of similar aquatic toxicity and to use the chloroform PNEC for total trihalomethanes. The Akzo Nobel draft Risk Assessment (reference 7) for chloroform estimates a

PNEC aquatic of 146 μg/l (see section 3.2.1.4 in reference 7)

5.3.4 PEC secondary disinfection by-products

The most important factor for the potential environmental impact of free active chlorine discharged in sea water is the formation of by- products, consisting of othe r oxidants (included in the TRO concept) and other chemicals. The power plant cooling water application of hypochlorite use is also here the most useful and comparable case for the EctoSysô ballast water treatment. The formation of by-products will vary strongly, both quantitatively and qualitatively,
due to the fluctuations in surf ace water composition, temperature, residence time, etc. The impact
of different environmental factors on the mech anism of by-product formation has been studied extensively (e.g. Handbook of American Wa ter Works, 1982). A summary of the main by-products generated by hypochlorite use in seawater cooling systems is given in table 9. The data represent actual measurements. In all situ ations it is observed that elevated by-product concentrations only occur in the n ear vicinity of the discharges.

Table 9: Measurement of by-products of hypochlorite application in cooling water in sea water, summarizing data from Jenner et al. 1997

Power stations No. of samples Bromoform ( μ g/l) Dibromoacetonitrile( μ g/l)

Average range Average range

90 16.32 ± 2.1 0.72ñ29.2 Several in UK,
F and NL 29 1.48 ± 0.56 < 0.1-3.15MEPC 55/2/4

ANNEX Page 39

I:\MEPC\55\2-4.doc For the marine cooling water scenario PEC values of TRO between 0 and 20 μ g/l were measured. Since hypochlorite is added at th e beginning of the cooling system it is expected that the TRO measured after discharge will be mainly a mixture of oxidative compounds other than hypochlorite. Since the nature of TR O is not identified it is not usef ul nor possible to determine a
PEC/PNEC ratio.

The actual formation of inorganic and organoha logen by-products will be highly dependant on specific local conditions and dosing regimes, whic h are normally under cont rol of local permits. The use of hypochlorite in cooling water is recen tly described in the reference document on the application of best available techniques (B AT) in industrial cooling systems (IPPC, 2000). Another useful recent publication was published by ElectricitÈ de France (Khalanski, 2002) on organic by-products from cooling water chlo rination from EDF mari ne power stations.
Measurements of the main trihalomethane form ed (bromoform) in cooling water samples from three power station showed bromoform levels up to 26.8 ug/l. The report assesses the risks of the main organic CBPís, concluding that the margins be tween the most sensitive toxicity thresholds
and the observed environmental concentrations fo r these power stations have safety factors of

10 3 to 10 7 for the local scale and 10 4 to 10 9 for the regional scale.

In situ measurements (plume sampling in the field) for 10 coastal power stat ions in France, the United Kingdom and the Netherlands were carried out for the following chemical class of compounds: haloforms, haloacetonitriles and hal ophenols. Five compounds were found at mean chlorine dosage levels of 0.5-1.5 mg/l (as Cl 2 ) of which 2 were consistently present above the detection limit. Bromoform was present in a ll effluents as well as dibromoacetonitrile. Dibromochloromethane, bromodichloromethane and 2,4,6-trichlorophenol were detected in a few cases at very low levels.

For by-product risk assessment, the chlorinati on of seawater (where brominated species predominate), probably represents a worse case in terms of by- product loads in effluents than freshwater chlorination. The environmental propert ies and toxicity of brominated and chlorinated species are similar, but the brominated oxidan ts formed are more reactive and have been observed to yield somewhat elevated levels of by-products, notably THMs (Pourmoghaddas and Stevens, 1995). This may to some extent be counteracted because by-product formation will be somewhat reduced at the higher pH that is typical of seawater.

The by-product concentrations from the EdF st udy (Khalanski, 2002) toge ther with data in
Table 9 would indicate conservative THM concen trations in the discharge during continuous dosing of approximately 30 μg/l. Ri sk characterization can then consider the case for sea water: For marine discharges in coastal zones the t echnical guidance documenta tion suggests a dilution factor of 100 can be considered as a worst case. This gives PEC local values of 0.3 μ g/l for THMs, which well serves as an indicative ìworst- caseî value for the ballast water discharge

case

. A conservative PEC/PNEC local for THM can thus be estim ated (PNEC = 146 μg/l, see section 5.3.3) and indicates no possible harm to the environment from THM originating in EctoSysô ballast water treatment.

5.3.5 Disinfection by-products associat ed with conventi onal chlorination

Chlorination disinfection by-produc ts (CDBPs) are chemical compounds that normally form when water containing natural organic matter (i.e all natural waters) is chlorinated. In
conventional chlorination of natu ral waters, the high concentra tions of free active chlorine species (i.e. Cl 2 , OCl - , HOCl) present inevitably leads to the formation of a number ofMEPC 55/2/4

ANNEX Page 40

I:\MEPC\55\2-4.doc chlorination by-products of which trihalomet hanes (THM:s) are only one subgroup. Among the many disinfection by-products caused by conventi onal chlorination (elect rochemical or not), THM:s are most often present and in the greatest c oncentration and as such are used as indicators of total disinfection by-product formation. THM:s ha ve been shown to be carcinogenic. It will be formed in unacceptable quantities using conventi onal electrochemical chlorine generators in ballast water management if special technical meas ures will not be taken to prevent formation or

remove CDBPs.

5.3.6 Disinfection by-products associated with ozonation

Using ozone as a disinfectant, bromate ion (BrO 3 - ) formation is a big potential concern with source waters containing bromide ions. Bromate is a chemical that is formed when ozone used to disinfect water reacts with naturally occurri ng bromide found in sour ce water. The oxidation reaction of bromide ion (Br - ) to hypobromite ion (BrO - ) and bromite ion (BrO 2 - ) and subsequently to bromate ion occurs due to direct reaction with ozone. Intermediate reactions can also occur through hydroxide radi cal mediated mechanisms if bromide is not present.

5.3.7 Disinfection by-product health effects, additional information

Some studies have been performed on disinf ection by-products health effects, but only concerning drinking water. Howe ver, it certainly raises con cern over the use of conventional
chlorination/ozonation in ballast water treatment systems. Since the discovery of chlorinated by-products in drinking water in 1974, numerous toxicological st udies (studies on the health effects from exposure to high dosages contaminan ts usually involving animals in a lab) have
been conducted. These studies have shown severa l disinfection by-products to be carcinogenic in laboratory animals (e.g., including bromate, certa in trihalomethanes and haloacetic acids). Some disinfection by-products have also been shown to cause adverse reproductive or developmental effects in laboratory animals (e.g., chlorite and certain trihalomethanes and haloacetic acids). However, there is considerable uncertainty involved in the results of high-dose, toxicological studies of some by-products o ccurring in disinfected drinking water to estimate the risk to humans from chronic exposure to low doses of these and other by-products.

In the area of epidemiology (studies of the factor s that influence disease in human populations), a number of studies have been completed inve stigating the relationship between exposure to
chlorinated surface water and cancer. Some have suggested an increased cancer risk to those exposed to chlorinated waters while others have demonstrated none. In issuing the Stage 1 Disinfectants/Disinfection By-products Rule base d on evidence then available, EPA stated that while the agency cannot conclude that there is a causal link between exposure to chlorinated surface water and cancer; these studies have sugge sted an association, albeit small, between bladder, rectal, and colon cancer and exposure to chlorinated surface water. There are fewer epidemiology studies evaluating the associatio n between exposure to disinfection by-products and reproductive and developmental effects. Again, some have suggested an increased risk from exposure to disinfection by-products while others have shown none. There remains considerable debate in the scientific community on the signif icance of these contradictory findings concerning
chlorinated water and disinfect ion by-products. As with cancer, EPA stated in its Stage 1 Disinfectants/Disinfection By-produc ts Rule that, based on data th en available, the agency can
not conclude there is a causal link between exposure to disinf ection by-products and reproductive and developmental effects. In sum, EPA be lieves the weight-of-evidence presented by the available epidemiological studies on chlorinate d drinking water and t oxicological studies on
individual disinfection by-products support a potential hazard concern and warr ant regulatory
action at this time such as that taken in the St age 1 Disinfectants/Disinf ection By-products Rule.MEPC 55/2/4

ANNEX Page 41

I:\MEPC\55\2-4.doc In the case of disinfection systems for ballast/sea water treatment, it is concluded that measures have to be made to monitor and keep the di sinfection by-product levels to a minimum.

6 TOXICITY TESTING OF THE TREATED BALLAST WATER (THE PROCEDURE (G9), SECTION 5.2)

6.1 Whole effluent toxicity testing

Brixham Environmental Laboratory (BEL), Astr aZeneca UK Limited, have run a series of aquatic toxicity tests on whole-effluents of sea water treated with the Ectosys ô ballast water treatment system [8]. The labor atory is certified according to GLP and consequently has archive dossiers of the complete experiment and raw- data, not included in this application.

Organisms representing three trophic levels (A lgae, crustacean and fish) have been used to represent species variations and lifestyles with different feedi ng strategies, which account for differences in sensitivity among different organism s. Acute toxicity te sting was selected to determine any short term effects from the effluent. This in itself provides a significant safety
factor since the timescale of diluti on of the discharged effluent wi ll be much shorter (of the order of a few hours) than the timescale of the test s (72 or 96 hours). Chronic toxicity data (the Procedure (G9), paragraph 5.2.2) was c onsequently not considered necessary.

These toxicity tests have been carried out for four differen t cases representing different environmental conditions and different operating c onditions of the unit; these conditions were full salinity (~35PSU) and half salinity (~17.5PSU ) at both nominal treatment conditions and by applying high (150% of nominal) current represen ting a ìworst caseî scenario. The treatments and storage time of the water was designed to si mulate a relevant real case of ballast water treatment using Ectosys ô as a disinfecting step: the water was filtered down to 20-40 μm and filled in a storage tank (1 m 3 ), then treated by the Ectosys ô unit (5m 3 /h) and stored for 48 h in a second tank, then treated again by the Ectosys ô unit immediately before the toxicological
studies.

The tests were conducted during the period 9 th January to 1 st February 2006 and in each case the effluents produced from the Ectosys ô unit were tested at two series of dilutions (100, 30, 10, 3 and 1 % v/v, and 30, 10, 3, 1 and 0.3 % v/v resp ectively). The results from the three trophic
levels and the four test conditions were very consistent. The wo rst case results from the tests

were:

Parameter % v/v Test Concentration causing 50% kill (LC 50) 5.5 turbot and rainbow trout Concentration causing 50% effect (EC50) 3.6 Algae (biomass) No effect concentration (NOEC) 3.0 All Lowest effect concentration (LOEC)* 10 All

*LOEC not possible to define further, since the statistical mode l does not have the proper input values (data from measurements between 3 and 10%)

A No Effect Concentration of 3% v/v translates to a requirement in the receiving water for a dilution of 33 times (100% ÷ 3%) for there to be potentially no effect on the environment. The
LOEC value should be considered as indicative. Th ese levels of toxicity are well in range with the expected from the worst case concentrations of TRO resulting from sea water treatment with the Ectosys ô . Dilution in the environment varies spat ially and with parameters such as the discharge rate, the ambient water speed and the tu rbulence. Therefore there is a need to combineMEPC 55/2/4

ANNEX Page 42

I:\MEPC\55\2-4.doc the toxicity results with predictions of dilutio n to make a risk assessment for the Ectosys ô process (see section 7).

Table 10: Summary of whole effluent toxicity test results (% v/v)

Start date,

Treatment Algae, 72h (biomass) Algae, 72 h (growth rate) Tisbe, 24 & 48 h Fish, 24 h

9/1/2006 Full salinity, high current EbC50 5.1% CI (2.8-7.4)%

NOEC (3.0%)* ErC50 8.8% CI (0-20)%

NOEC 3.0% 24 h LC50 9.7% CI (5.4-17)%

48 h LC50 8.1% CI (4.4-14)% Turbot:

LC50 5.5% CI (3-10)%

16/1/2006 Full salinity,
normal current EbC50 9.2% CI (0-19)%

NOEC 3.0% ErC50 11% CI (5.4-16)%

NOEC 3.0% 24 h LC50 11% CI (6.0-19)%

48 h LC50 8.1% CI (4.4-14)% --

23/1/2006 Half salinity, high current EbC50 5.5% CI (1.7-9.4)%

NOEC 3.0% ErC50 6.4% CI (5.3-7.6)%

NOEC 3.0% 24 h LC50 8.1% CI (5.3-13)%

48 h LC50 5.5% CI (3-10)% Rainbow Trout:

LC50 5.5% CI (3-10)%

30/1/2006 Half salinity,
normal current EbC50 3.6% CI (2.1-5.0)%

NOEC 3.0% ErC50 7.1% CI (4.1-10)%

NOEC 3.0% 24 h LC50 14% CI (10-22)%

48 h LC50 14% CI (10-22)% --

LC50 ñ concentration causing 50% kill (fish and Tisbe ).
CI ñ 95% confidence interval. EbC50 - concentration causing a 50% reduction in the Algae growth based on the biomass

measurements. ErC50 - concentration causing a 50% re duction in the Algae growth rates.
NOEC ñ No Observable E ffect Concentration.
LOEC ñ Lowest Observable Effect Concentration. * NOEC, LOEC could not be define d statistically, values given are as perceived by the operator (see Appendix 3 of reference [8]).

6.2 Ecotoxicity test of treated natural se a water (the Procedure (G9), section 5.1.1)

The persistence of total toxicity in Ectosysô tr eated natural sea water ha s been screened during 2003 with a ecotoxicity test, perf ormed by marine biologist and c onsultant Dr. F. NorÈn. The Ectosysô unit was running under nominal operating conditions treating natu ral sea water at the west coast of Sweden. Three different test orga nisms were added after different storage periods after treatment, and the survival was analysed with the ìlive-d eadî method. Storage was made at approx. 5-10°C, in dark, closed 1 litre containers. The test orga nisms were unfortunately chosen due to convenience of other surrounding efficiency tests. The results ar e shown in figure 7.MEPC 55/2/4

ANNEX Page 43

I:\MEPC\55\2-4.doc Ekotox- test of stored natural sea water treated with EctoSys, nominal

conditions

0 10 20 30 40 50 60 70 80 90 100

Controll t=0 min t=30min t=60 min t=5 h
Storage time before addition of organismssurvival rate, %

Isochrysis

Pavlova

Artemia

Figure 7: Ecotox test results from te sting remaining toxicity of Ectosys ô treated sea water

Any conclusions that can be drawn from this study have to be made from the Pavlova results,
while the Artemia survived to almost 100% through the experiment, and Isochrysis died instantly even in the untreated water (The ìcontrollî). The Pavlova results indicate that toxicity of Ectosys ô treated water is decreased after approx. 1-5h under conditions similar to the ballast
water storage case.

7 MODELLING OF BALLAST WATE R DISCHARGE INTO RECEIVING
WATERS

Versatile computer software has been developed to predict discharge diluti on scenarios in generic harbours. Both harbours of ìopenî and ìclosed î types can be simulated, the number of discharging ships, different discharge rates and total volumes of treated ballast water along with decay, traffic, tidal flows etc. are considered by the model. The software has been developed (and calculations carried out) by Astra Zeneca Brixha m Environmental Laboratory in Brixham, the United Kingdom, a GLP certified la boratory with expertise in the area. Table 11 in section 7.2 are some results from these calculations, rangi ng from reasonable ìreal caseî discharge to unreasonable high discharge volumes. In these exam ples, the discharge from one ship has been modelled for simplicity and overview. Simulations were allowed to run to predict the time duration after discharge for concentration to fa ll below 3% (NOEC) everywhere in the water
volume. An overall whole effluent NOEC of 3% was indicated by the whole-effluent toxicity tests (see section 6.1).

7.1 Definitions of generic harbours:

Closed:

800 m × 190 m, depth 12 m. Ship at 400 m, 10 m with discharge onto surface

Open:

Model domain is 7000 m × 300 m, depth 12 m. Ship at 3500 m, 10 m with discharge onto
surfaceMEPC 55/2/4

ANNEX Page 44

I:\MEPC\55\2-4.doc 7.2 Model results

Table 11: Predicted time to reach NOEC (3%) dilution after discharge of different rates and volumes of ballast water treated with EctoSysô

Discharge Closed harbour Open harbour 1,000 m 3 /h, 5 h 19 h 1 h 1,000 m 3 /h, 10 h 24 h 1 h 5,000 m 3 /h, 5 h 114 h 6 h 5,000 m 3 /h, 10 h > 500 h* 20 h

* 500 hrs after discharge end (Con centrations in % neat effluent)

7.3 The influence of decay to overa ll toxicity reduction, example

Some examples taking the toxicity reduction over time (see section 6.2) have been carried out. Assuming (as an absolute worst case) toxi city degrades in 24 hrs and follows 1 st order degradation, and run the simulation at the 5,000 m 3 /h, 10 h, closed harbour-case, gives:

3%=100%.exp(-kdeg.24)

Which implies that kdeg=0.146 hr -1

Rerun of a specific case (5,000 m 3 /h, 10 h, closed harbour) with th is degradation rate gives the
answer 12 hrs after discharge until concentrations belo w 3% of neat efflue nt. (3% = NOEC). This can be compared to the result > 500 h without co nsidering any decay of the toxic substances.

8 SHIP AND PERSONAL SAFETY (THE PROCEDURE (G9), SECTION 6.3)

8.1 General

No risks with handling chemicals can be associat ed with the EctoSysô ballast water treatment system. Active Substances and relevant chemicals are produced in situ and not handled by the crew or suppliers at any part of the process. The water is typically tr eated both during ballasting and deballasting. Concentration of hydroxyl radicals in the efflue nt water to the ballast water tank will be zero, and concentra tion of by-produced free active chlori ne species will be negligible small and therefore not a threat to human health, ship or environment. All electrical equipments are built from CE labelled parts and no voltages da ngerous to human health will be applied. The electrical wiring and current feeders will be totall y screened off externally, and no voltage will be applied between parts that are subject to handlin g by the crew or supplier. The EctoSysô ballast water treatment system is equipped with a number of automatic safety clamping devices that will shut the system off if an external emergency (s uch as for instance pump fa ilure causing decreased flow rates) occurs. All parts ar e built from metallic or non-flammable materials, approved for use on ships. Maintenance procedures will not pos e threats to operating personnel, surrounding equipment, the environment or to the general operation of the ship.MEPC 55/2/4

ANNEX Page 45

I:\MEPC\55\2-4.doc 8.2 Corrosion

The corrosive properties of wate r treated by the EctoSysô ballast water treatment system will not differ significantly from untreated water. Th e redox potential of natu ral sea water (35 PSU) treated under relevant conditions by the Ec toSysô will increase a maximum of 100 mV immediately after treatment and, because of the chemical diversity of natural waters and the degradation of free active chlorine, rapidly decrease again back to natural values.

Corrosion tests according to ASTM standard test procedures have been considered. The most relevant in the case of electrochemically treated marine and brackish waters used on ships would
be the ASTM G31-72: ìStandard Practice for Laboratory Immersion Corrosion Testing of
Materialsî and ASTM D1654-05: ìStandard Test Method for Evaluation of Painted or Coated Specimens Subjected to Corrosive Environmentsî. However, the data achieved from such tests would naturally not be of any use in the evaluation of possibl e actual corrosion cases on-board ships. The Applicant has approached this problem by instead launching long-term corrosion studies that will proceed during both land-based type approval test phase and also verified at the shipboard type approval test phase (see below).

The claim that the corrosive properties of wa ter treated with the EctoSysô ballast water treatment system will not change has been partly confirmed during on-going case studies in
Bremerhaven where the short term effects on different kinds of steel (non-coated or painted with standard protective coatings) have been evaluated. The physioch emical properties relevant to corrosiveness (e.g. redox potential and pH) have b een measured continuously at releva nt running
conditions. Batch tests were carri ed out according to DIN EN 12502 with piping parts (St37-2, zinc plated) exposed to influent water and effluents treated by EctoSysô over five weeks. The water was renewed every 2 ñ 7 days simulating ballasting operation. No significant changes in the parameters temperature, conductivity, re dox potential, oxygen content or pH could be detected. Besides a small formation of protecting zinc carbonate layers no corrosion was visible on the piping parts. Batch tests on corrosion do not represent the complex interaction between abrasion and corrosion, which occur in flow through systems. Consequently, new long-term (> 6months) tests are planned in real scale with ballast water tank design, linked to the land-based type approval experimental setup. Th e results along with in-house expertise opinions will be reported continuously during these trials in 2006-08.

Hydroxyl radicals produced in the water is neither influenced by pH nor influencing pH value
themselves in natural waters. The constructio n of the EctoSysô electrochemical cell with periodic oxidation/reduction throughout the treatm ent prevents a net change of the balance
between H + /OH - ions. Thus, EctoSysô treatment of sea water/brackish water will not have any impact on the pH value of the water. The theore tical, small, influence there might be is also effectively counterbalanced by the buffering capacity of natural sea water. Figure 8 shows the pH
difference between influent- and effluent wate r of the EctoSysô during treatment, nominal operating flow rate, of natural sea water in Bremerhaven harbour, Germany. It was thus concluded that the main parameters influencing the corrosive properties of the sea water remains practically unchanged from EctoSysô treatment.MEPC 55/2/4

ANNEX Page 46

I:\MEPC\55\2-4.doc 6 7 8 9

0 5 10 15 20 25

current in ApH influent

effluent

Figure 8: Influence of EctoSysô treatment on th e pH of sea water (mea sured on-line, ProMinent test probes)

8.3 Production of hydrogen gas

Beside preventing chlorinated di sinfection by-products, such as THM:s, to form, the EctoSysô cell design and electrode conf iguration also has positive e ffects on the net-production of hydrogen gas. Instead of only producing hydrogen gas (H 2 ) on the cathode, oxygen gas (O 2 ) and
also the small amounts of chlorine gas (Cl 2 ) produced at the anode will undergo reduction
reactions on the cathode. This is possible due to the short distance between the electrodes, electrode configuration and turbulence prom oting structure. (Pat ent application no.: WO2005058761(A1)). The reduction of oxygen dissolved in the water as competitive reaction to formation of hydrogen gas on relevant electrode ma terials have been theoretically studied using cyclic voltammetry in solutions with varying concen trations of NaCl [8]. It was concluded that oxygen reduction was a major cathode reaction in oxyge n saturated electrolytes such as e.g. sea
water/ballast water.

Hydrogen gas may theoretically be formed during an electrolysis process in water. However, in
the case of electrochemical in-lin e ballast water treatment such as EctoSysô where all the ballast water is treated during a single flow through the cell, no harmful concentrations will build up in the ballast water tanks or surrounding systems. Th is is partly because continuous venting of the ballast water tanks are necessary during ballastin g and deballasting, making it impossible to build up explosive concentrations (4%) of hydrogen ga s in the ballast water tanks. For surrounding systems (pipings etc.) a reliable degassing will be also included to the complete ballast water treatment system. In the partic ular case of EctoSysô, it is both theoretically and practically confirmed that much less hydrogen gas will be pr oduced compared to conventional in-line sea water electrolysis. The actual production of and current exchange for hydrogen gas during EctoSysô treatment of water with relevant salin ities have been preliminary analysed according to the following procedure: An e ffluent tank with a total volume of 1100 l was installed at the effluent of a pilo t plant (EctoSysô 10m 3 /h unit treating natural sea water, Bremerhaven, Germany). The effluent was continuously flown th rough with the same flow rate used in the influent to the pilot plant. The water volume in the effluent tank was approx. 735 l and the gas phase volume approx. 365 l. The effluent tank was closed by a cover, and the hydrogen gas in the gas phase above the water was measured by a Draeger PAC III H 2 -sensor at different flow ratesMEPC 55/2/4

ANNEX Page 47

I:\MEPC\55\2-4.doc and each maximum hydrogen concentration was r ecorded. The concentrations formed in the
closed tank never achieved da ngerous levels. Hydrogen and oxyge n gas mixture is ignitable when the hydrogen reaches at least 4 %, which never occurred. Figure 9 shows the built up hydrogen gas concentration in the tank gas phas e at worst case operational parameters. For
onboard installations a reliable degassing will be also included to the complete ballast water
treatment system.

Hydrogen formation, EctoSys treatment at worstcase applied current

0 500 1000 1500 2000 2500 3000 3500 4000

0123456789

Flow rate, m3/h, (nominal: 10m3/h)H2 conc. in tank gas-phase,ppm

Figure 9: Built up hydrogen gas (H 2 ) concentration in the tank gas phase after EctoSysô treatment at worst- case operational parameters. Nominal flow rate for this system is

10m 3 /h, explosive/dangerous level of hydrogen concentration is 4,000 ppm.

Bench scale tests using authentic EctoSysô cell s and electrodes will be conducted to more in detail investigate the influence of the physical parameters (e.g. sali nity, TOC, pH) of the water to the formation of hydrogen. Field tests (using na tural sea water) on the hydrogen formation will
also be conducted linked to life- time tests of EctoSysô cells and electrodes. All these tests will be continuously on-going and re ported during the type-approval/shi pboard testing process, along with mathematical case-study modelling.

9 ASSESSMENT REPORT (THE PROCEDURE (G9), SECTION 4.3)

Handling of the Active Substances and Preparations (the Procedur e (G9), section 7. 1) is not an issue for the system proposed by the applican t, where the Active S ubstances are formed in situ

. The Akzo Nobel comprehensive documentation over free active chlorine includes a complete risk assessment report over such substances (see re ference 7) and is available as stated in paragraph 4.2.5 of the Procedure (G9). The whole-effluent tests a nd analysis on toxicity for the EctoSysô BWT treatment system are based on both nominal treatment conditions as well as worst-case scenarios, and have been performed by certified la boratory accredited to GLP. Analysis results combined with toxicity data, degradation data/predictio ns and risk assessment shows that even if high safety factors are appl ied, we assess that no harm will be done to the surrounding environment, ship or crew using the EctoSysô as a di sinfection step in ballast water management systems. However, si nce certain toxicity, specified in this document, was found in the effluent water; it might be considered n ecessary to assess this local immediate marine environmental impact against the potentially ca tastrophic environmental impact of introducing alien species into new biotopes. The WHO type of risk/benefit analysis can be used based on the Convention on Biological Diversit y (CBD), Article 14, and also publications in the areaMEPC 55/2/4

ANNEX Page 48

I:\MEPC\55\2-4.doc [see reference 10]. The vital data of this application (whole e ffluent toxicity, water quality
control and influence of all rele vant water parameters) will be confirmed during the following performance tests, including the land-based full scale type approval proce dure. The chemistry of
the Active Substances in natural waters is cons idered well-known as far as formation of toxic substances, and also concerning by-products that w ill form in detectable quantities. Uncertainties (the Procedure (G9), paragraph 6.4.3) of this assessment are mainly linked to possible up-scaling problems, while the data given in this docu ment are mainly based on small-scale pilot equipments. This will however be thoroughly inve stigated and reported during the following test phases. The GESAMP- Ballast Water Working Group is invited give their vi ew of this, and to
continue assessment of the nominal and worst-ca se approach and the re levancy and quality of performed tests in this document.

10 REFERENCES

.1 ìUllmannís Encyclopedia of Industrial Chemistryî, Copyright © 2002 by Wiley-VCH Verlag GmbH & Co. KGaA. All ri ghts reserved. DOI:10.1002/14356007.a09_183, Article Online Posting Date: January 15, 2003.

.2 D. C. Johnson, N. Popovic, J. Feng, L. L. Houk, K. T. Ka wagoe, The Electrochem. Society, Proc. Volume 95 ñ 26, 176 ñ 188 (1996).

.3 C. Comninellis, ìElectrolysis in the elec trochemical conversion/combustion of organic pollutants for waste water treatmentî, Elect rochemical Society, Proceedings pp.75-86 (1994).

.4 K. Yamamoto et al. ìEmpirical model for disappearance of free oxidants in natural water with wide salinity and ammonia range sî, Water Res.Vol.19, No. 12, pp.1595-1599 (1985).

.5 M. H. Lietzke, ìA kinetic model for pr edicting the composition of chlorinated water discharged from power plant cooling syst emsî, Water Chlorination, Vol. 2, pp.707-716 (1978).

.6 P. Hoestgaard-Jensen et al . ìChlorine decay in cooling water and discharge into seawaterî, Water Pollut. Control Fed., Vol. 49, pp.1832-1841 (1977).

.7 ìRISK ASSESSMENT REPORT FOR S ODIUM HYPOCHLORITE, DRAFT.î Akzo Nobel NV, November 2005.

.8 A M Riddle, A D Lillicrap, P J Nicholson, ìAssessment of the toxicity of the effluent from the EctoSysô bilge water treatment systemî, Brixham Environmental Laboratory study number Z0457, Report No BL8298/B, March 2006.

.9 M. Behm, ìGrundl‰ggande studie av BDD- elektroder i natriumklo ridlˆsningî, The Royal Institute of Technology KTH, March 2006.

.10 Jeff McNeely, ìInvasive species: a costly ca tastrophe for native biodiversityî, Land Use and Water Resource Research 1, 2, pp.1-10 (2001).MEPC 55/2/4

ANNEX Page 49

I:\MEPC\55\2-4.doc .11 M. Fabbricino, G.V. Korshin, ìFormation of disinfection by-products and applicability of absorbance spectroscopy to monitor halogena tion in chlorinated coastal and deep ocean seawaterî, Desalination 176, pp 57-69 (2005).

11 ABBREVIATIONS

AOX: Absorbable Organic halogens BAT: Best Available Techniques
BPD: Biocidal Products Directive
BWT: Ballast Water Treatment CBD: Convention on Biological Diversity
CPO: Chlorine Produced Oxidants (C)DBP: (Chlorinated) Disi nfection By-Products DSAô: Dimensionally Stable Anodes
FAC: Free Active Chlorine GLP: Good Laboratory Practice
HAA: Haloacetic acids
NOEC: No Observable Effect Concentration
PEC: Predicted Environmental Concentration
PNEC: Predicted No Effect Concentration ROS: Reactive Oxidative Species
TGD: Technical Guidance Documents (T)THM: (Total) Trihalomethanes TOC: Total Organic Carbon
TRC: Total Residual Chlorine
TRO: Total Residual Oxidants TSS: Total Suspended Solids

__________