I:\MEPC\61\2-11.doc 

E

MARINE ENVIRONMENT PROTECTION 

COMMITTEE 

61st session 

Agenda item 2 

MEPC 61/2/11

29 March 2010

 Original: ENGLISH

HARFMUL AQUATIC ORGANISMS IN BALLAST WATER 

Application for Basic Approval of the ERMA FIRST Ballast Water Management System 

Submitted by Greece 

SUMMARY 

Executive summary: This document contains the non-confidential information related to 

the application for Basic Approval of the ERMA FIRST Ballast 

Water Management System submitted in accordance with the 

"Procedure for approval of ballast water management systems that 

make use of Active Substances (G9)" adopted by resolution 

MEPC.169(57) 

Strategic direction: 7.1 

High-level action: 7.1.2 

Planned output: 7.1.2.5 

Action to be taken: Paragraph 6 

Related documents: BWM/CONF.36; MEPC 57/21; BWM.2/Circ.13 and BWM.2/Circ.24 

Introduction 

1 Regulation D-3.2 of the International Convention for the Control and Management of 

Ships' Ballast Water and Sediments stipulates that ballast water management systems that 

make use of Active Substances to comply with the Convention shall be approved by the 

Organization. 

2 The "Procedure for approval of ballast water management systems that make use of 

Active Substances (G9)" determines the required information (MEPC 57/21, annex 1, 

paragraph 4.2.1) and provides details for the risk characterization and analysis 

(MEPC 57/21, annex 1, paragraph 5.3). In accordance with the section 6 of the 

above-mentioned Procedure, the Organization should evaluate the information provided in 

the application. 

3 The competent authority in Greece has verified the application dossier prepared by 

ERMA FIRST S.A. and believes it to satisfy the data requirements of Procedure (G9) 

adopted by resolution MEPC.169(57). 
MEPC 61/2/11 

Page 2 

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4 According to BWM.2/Circ.24, proposals made for the approval of ballast water 

management systems that make use of Active Substances are to be submitted to the 

Marine Environment Division of the Organization to be reviewed by the GESAMP-Ballast 

Water Working Group. In the meantime, a document on the above-mentioned proposals 

containing all the non-confidential information on the specific ballast water management 

systems that make use of Active Substances must be submitted to MEPC 61. 

5 Greece submits the non-confidential part of the applicant's dossier, in the annex of 

this document, to the Organization for evaluation according to Procedure (G9). The 

complete dossier will be made available to the experts of the GESAMP-Ballast Water 

Working Group with the understanding of confidential treatment. 

Action requested of the Committee 

6 The Committee is invited to consider the proposal for approval and decide as 

appropriate. 

*** 
MEPC 61/2/11 

Annex, page 1 

I:\MEPC\61\2-11.doc 

ANNEX 

NON-CONFIDENTIAL INFORMATION ON THE ERMA FIRST BALLAST WATER 

MANAGEMENT SYSTEM 

Contents 

1 PREFACE 

2 IDENTIFICATION OF THE SUBSTANCES OR PREPARATIONS 

3 EFFECTS ON AQUATIC TOXICITY 

4 DATA ON MAMMALIAN TOXICITY 

5 DATA ON ENVIRONMENTAL FATE AND EFFECT UNDER AEROBIC AND 

ANAEROBIC CONDITIONS 

6 PHYSICAL AND CHEMICAL PROPERTIES OF THE ACTIVE SUBSTANCES, 

RELEVANT CHEMICALS AND TREATED BALLAST WATER 

7 ANALYTICAL METHODS AT ENVIRONMENTALLY RELEVANT CONCENTRATIONS 

8 USE OF ACTIVE SUBSTANCE 

9 MATERIAL SAFETY DATA SHEETS AND CLASSIFICATION OF HAZARDS 

10 RISK CHARACTERIZATION AND ANALYSIS 

11 EVALUATION OF TREATED BALLAST WATER 

12 RISK ASSESSMENT 

13 ASSESSMENT REPORT 
MEPC 61/2/11 

Annex, page 2 

I:\MEPC\61\2-11.doc 

1 PREFACE 

1.1 Profile of the manufacturer 

ERMA FIRST E.S.K. Engineering Solutions S.A., the manufacturer of the ballast water 

management system, presented in this dossier is a new company stemming from the 

Environmental Protection Engineering S.A., a Greek designer and producer of shipboard and 

industrial liquid waste treatment equipment. In particular, type-approved oily water 

separating (filtering) equipment and sewage treatment plants have been produced for more 

than 25 years serving the needs of the Greek and foreign shipping industry. 

Environmental Protection Engineering S.A. was one of the partners that co-operated on the 

materialization of the three-year project "Οnboard Treatment of Ballast Water and Application 

of Low Sulphur Marine Fuel – MARTOB" carried out from April 2001 to June 2004, in the 

context of the Competition and Sustainable Growth Programme funded by the European 

Commission. The objectives of this project relating to ballast water management were to 

investigate the various possible methods for controlling the transfer of non-indigenous 

organisms through ballast water and develop technologically and economically viable 

solutions to the problem by testing and assessing safe and environmentally friendly 

treatment methods that have a minimum impact on ship operations. 

Following the research carried out for development and optimization of the system, toxicity 

testing of ballast water was carried out in the Institute of Marine Resources and Ecosystems 

Studies Wageningen (IMARES) in the Netherlands in February 2010. Pre-certification and 

land-based testing of a 100 m3

/h pilot treatment system commenced in March 2010 in the 

Royal Netherlands Institute for Sea Research (NIOZ) which is the National Oceanographic 

Institution of the Netherlands. 

1.2 Outline of the ERMA FIRST ballast water management system 

The ERMA FIRST Ballast Water Management System is an integrated, autonomous and 

modular treatment system for ballast water, jointly developed by a group of scientists and 

engineers with a long experience in the design and production of equipment for ship-generated 

liquid waste treatment. The nominal treatment capacity of each module is 100 m3

/hr. Basic 

drawings illustrating typical arrangements of the system are presented in appendix 1 of the 

confidential dossier. 

The treatment process includes two distinctive stages, a primary one that enables the 

separation of coarser suspended materials and relatively larger living organisms in ballast 

water and a secondary one, in which electrolytic disinfection takes place to meet the required 

biological efficacy standard for treated ballast water as stipulated in the BWM Convention. 

At the primary stage of the process, removal of material with size larger than 20 μm is 

accomplished by means of an advanced cyclonic separator made from frictionless material. 

To prevent blocking of the separator from large particles that might pass though the sea 

chests and strainers of the vessel, a 500 μm self cleaning basket filter has been installed 

prior to the separator. The benefits offered from the pre-filtering and the cyclonic separation 

towards the removal of coarse inorganic and organic material present in ballast water relate 

to a lower disinfectants concentration demand which in turn results in less energy and 

electrodes coatings consumption. 

Electrolysis of ballast water for producing in situ up to 10 mg/L of free active chlorine 

constitutes the second stage of treatment which takes place during ballasting. The products 

of this process flow into the ballast tanks of the vessel, so that the residual oxidants disinfect

any harmful organisms taken onboard. Integral components of the system are the control 
MEPC 61/2/11 

Annex, page 3 

I:\MEPC\61\2-11.doc 

and monitoring equipment that ensure its proper operation as well as the neutralization 

process of treated ballast water prior to its eventual discharge into the sea. The operational 

status of the system is continuously monitored at a central data logger, located into the 

central control panel of the system. Data logging includes the operation status of the system, 

operation, flow and temperature at the electrolytic cell, pressure difference across the 

self-cleaned filter and the cyclonic separator, the operational status of the neutralizing agent 

dosing pump as well as the chlorine level of the system. The control panel can be positioned 

into the cargo control room of the vessel. All major components including pressure 

difference sensors, flow sensors, chlorine sensors, the neutralizing agent dosing pump, etc., 

described in detail in the section 8 of the confidential dossier, transmit and/or receive their 

output and/or input as 4-20 mA signals. 

During de-ballasting, neutralization of the total residual chlorine takes place by adding 

aqueous solution sodium bisulfite solution. At this mode, the pre-filtering equipment, the 

cyclonic separator and the electrolytic cell of the system is by-passed with the exception of 

the second free chlorine sensor. When de-ballasting begins, the dosing pump of sodium 

bisulfite starts operating at a pre-set value of 20 mg/L. This is based on the worst case 

scenario, which is the need for de-ballasting the water directly after the ballasting process, 

with minimum retention time. 

2 IDENTIFICATION OF THE SUBSTANCES OR PREPARATIONS 

Electrolysis of ballast water results in the formation of hypochlorous acid (HOCl) in 

equilibrium with hypochlorite ion (OCl-

) and due to the presence of bromide ions in seawater 

also to the formation of hypobromous acid (HOBr) in equilibrium with hypobromite ion (OBr-

)

supplementing the deactivation of harmful aquatic organisms. The chlorine and bromine 

based Active Substances produced in the electrolytic cell eventually flow to the ballast water 

tanks where residual concentration is maintained to ensure complete and effective 

deactivation of invasive species and eliminate their re-growth. Electrolysis of ballast water 

takes place only during ballasting operation, the products of which flow in the ballast tanks of 

the vessel so that the residual oxidants deactivate any harmful organisms taken on board. 

Both hypochlorous acid and hypochlorite ion have very distinctive behaviour in terms of their 

killing and inactivating effect to micro-organisms as well as to other marine organisms. 

In general, the effectiveness of disinfection is dependent on the pH of the water and 

disinfection with chlorine is optimized when the pH is between 5.5 and 7.5. Free available 

chlorine is defined as the concentration of the following three forms of chlorine present in the 

water: dissolved gas Cl2, hypochlorous acid (HOCl) and/or hypochlorite ion (OCl-

) which exist 

together in equilibrium. Their relative proportions are strongly dependent on pH and also on 

temperature, ionic strength as well as the total (initial) concentration of chlorine present. 

Between pH 2 and 7, the equilibrium is in favour of HOCl while at pH below 2, the predominant 

form is Cl2. At 25°C and pH 7.4, HOCl and OCl- are about equal while above this value, 

OClis the predominant form of free chlorine. It is noted that ocean pH varies from about 7.90 

to 8.20 but along the coastline, larger variations from 7.3 in estuaries or in up welling zones 

exist to 8.6 in productive coastal plankton blooms might be measured. At the anode of the 

cell, where chlorine ions migrates, chlorine gas dissolves rapidly in the water and hydrolyses 

to produce hypochlorous acid (HOCl), which in turn, depending on the pH of the water, forms 

hypochlorite ions (OCl-

). The Active Substances and Relevant Chemicals generated during 

the ballast water treatment as well as sodium bisulfite (used in the neutralization of treated 

ballast water prior to its discharge into the sea) identified as Other Chemicals, are summarized 

in the following table: 
MEPC 61/2/11 

Annex, page 4 

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Table 1: List of AS, RC and OCs 

Chemical Name CAS Number AS, RC or OC 

Sodium Hypochlorite 

(HOCl, OCl-

) 7681-52-9 AS 

Sodium Hypobromite 

(HOBr, OBr-) 13824-96-9 AS 

Chlorodibromomethane 124-48-1 RC 

Tribromomethane 75-25-2 RC 

Trichloromethane 67-66-3 RC 

Dichlorobromomethane 75-27-4 RC 

Sodium Bromate 7789-38-0 RC 

Monobromoacetic acid 79-08-3 RC 

Dichloroacetic acid 79-43-6 RC 

Dibromoacetic acid 631-64-1 RC 

Bromochloroacetic acid 5589-96-8 RC 

Trichloroacetic acid 76-03-9 RC 

Hydrogen 1333-74-0 RC 

Sodium Bisulfite 7631-90-5 OC 

Note: AS – Active Substances; RC – Relevant Chemicals; OC – Other Chemicals 

3 EFFECTS ON AQUATIC TOXICITY 

Short-term LCs and NOECs from toxicity testing mainly on seawater species representing 

three trophic levels, identified from various literature sources are summarized in the section 3 

of the application dossier for each one of the Active Substances generated during the ballast 

water treatment process. 

Endocrine disruptors encompass a variety of chemical classes, including natural and 

synthetic hormones, plant constituents, and pesticides as well as other industrial by-products 

and pollutants. Endocrine disruptors have been defined as "exogenous substances that alter 

function(s) of the endocrine system and consequently cause adverse health effects in an 

intact organism, or its progeny" (WHO, 2002). Search into various literature sources showed 

no indication that the Active Substances, Relevant Chemicals or Other Chemicals may be 

regarded as endocrine disruptors. 

The organic carbon-water partitioning coefficient (Koc) is the ratio of the mass of a chemical 

that is adsorbed in the sediment per unit mass of organic carbon in the sediment per the 

equilibrium chemical concentration in solution. None of the Active Substances, Relevant 

Chemicals and Other Chemicals appears to have the potential to be adsorbed to surface 

sediments to a significant extent based, on the one hand, on the Koc values identified from 

various literature sources and, on the other hand, on the information on bioavailability/ 

biomagnification/bioconcentration provided in the following paragraph. 
MEPC 61/2/11 

Annex, page 5 

I:\MEPC\61\2-11.doc 

Table 2: Koc values for the identified AS, RC and OC 

Chemical Name Koc (l/kg) Reference 

Sodium Hypochlorite 14.3 MEPC 60/2/3 

Chlorodibromomethane 84 HSDB Database 

Tribromomethane 116-126 HSDB Database 

Trichloromethane 65 HSDB Database 

Dichlorobromomethane 54.38 Epi Suite 

Sodium Bromate 31.8 Epi Suite 

Monobromoacetic acid 39.8 HSDB Database 

Dichloroacetic acid 75 HSDB Database 

Dibromoacetic acid 1.5 HSDB Database 

Bromochloroacetic acid 1.9 HSDB Database 

Trichloroacetic acid 130 HSDB Database 

Sodium Bisulfite 2.2 MEPC 60/2/3 

The ability of a chemical to bioaccumulate through the food chain is measured by the 

Bioconcentration Factor (BCF). Log Kow, defined as the ratio of the equilibrium 

concentration of a dissolved substance in a two-phase system comprising two largely 

immiscible solvents, n-octanol and water, with the first substance representing the fatty 

tissues of the living organism, is recognized as that physiochemical property that can be 

used to indicate the potential of a chemical to bioaccumulate. 

However, some products that have a high Log Kow may be metabolized quickly in reality and so 

do not actually bioaccumulate. Others, such as long chain alkanes are rapidly metabolized 

into natural body compounds (fatty acids) and become incorporated into other natural 

compounds. According to the revised GESAMP Hazard Evaluation Procedure, for log Kow 

values of ≥ 4, a measured BCF is required to provide definitive information on the potential 

of a substance to bioaccumulate under steady state conditions. The substances most likely 

to pose a hazard to aquatic organisms through bioaccumulation typically have log Kow 

values ranging from 4 to 7. The log Kows for the Active Substances, Relevant Chemicals 

and Other Chemicals are less than 3, indicating their low potential to bioaccumulate. 

In addition, measured BCF values are less than 100, as shown in the following table: 

Table 3: Bioconcentration Factors for identified Active Substances 

and Relevant Chemicals 

Chemical Name BCF (l/kg) Reference 

Sodium Hypochlorite -2.19 MEPC 60/2/3 

Sodium Hypobromite 1.24 MEPC 60/2/3 

Chlorodibromomethane 9 HSDB, 2009 

Tribromomethane 14 HSDB, 2009 

Trichloromethane 2.9 – 10.35 MEPC 59/2/11 

Dichlorobromomethane 7.0 HSDB, 2009 

Sodium Bromate No data available No data available 

Monobromoacetic acid 3.2 HSDB, 2009 

Dichloroacetic acid 3 TOXNET 2008 

Dibromoacetic acid 0.17 HSDB, 2009 

Bromochloroacetic acid 3.2 HSDB, 2009 

Trichloroacetic acid 0.4 – 1.7 TOXNET 2008 

Sodium Bisulfite 3.2 MEPC 60/2/9 
MEPC 61/2/11 

Annex, page 6 

I:\MEPC\61\2-11.doc 

The above-mentioned substances that might be present in the water overlying surface 

sediments would not readily be absorbed into them due to the relatively low organic 

carbon-water partitioning coefficient values. In parallel, the values of Bioconcentration 

Factors presented in section 3.5 indicate that little bioconcentration/bioaccumulation will 

occur in aquatic organisms and that little biomagnification across the aquatic and mammalian 

food web is expected. 

Long-term NOECs or ECs mainly from seawater species representing three trophic levels 

identified from various literature sources, are summarized in section 3.2 of the application 

dossier for each one of the Active Substances generated during the ballast water treatment 

process. The data provided are the lowest toxicity values found for fish, crustaceans, and 

algae. It must be noted that no data were found for dibromochloromethane, dibromoacetic 

acid and bromochloroacetic acid. 

4 DATA ON MAMMALIAN TOXICITY 

Similarly, data on mammalian toxicity including acute toxicity, effects on skin and eye 

sensitization effects, repeated dose toxicity, development and reproductive toxicity, chronic 

toxicity, carginogenicity/mutagenicity/reprotoxicity and toxicokinetics are also presented in 

section 4 of the application dossier. 

5 DATA ON ENVIRONMENTAL FATE AND EFFECT UNDER AEROBIC AND 

ANAEROBIC CONDITIONS 

5.1 Modes of degradation 

Biotic degradation could be held under aerobic or anaerobic conditions. Degradation of 

compounds is conducted also by anaerobic conditions. Furthermore, chemicals in aquatic 

environments, soil and air may be transformed by abiotic processes such as hydrolysis, 

oxidation and photolysis. According to literature, Actives Substances such as hypochlorous 

acid and hypobromous acid decay within seconds and produce an oxidizing environment. 

Under these environment trihalomethanes and haloacetic acid are produced (Relevant 

Chemicals). Section 5.1 of the confidential dossier summarizes the modes of environmental 

degradation in biotic and abiotic conditions for Active Substances and Relevant Chemicals 

generated by the ballast water treatment system. 

5.2 Bioaccumulation, partition coefficient, octanol/water partition coefficient 

Bioconcentration factor (BCF) is the concentration of test substance in/on the fish or specified 

tissues thereof divided by the concentration of the chemical in the surrounding medium at 

steady state (as L/kg). Bioconcentration factors (BCFs) are used to relate pollutant residues 

in aquatic organisms to the pollutant concentration in ambient waters. Many chemical 

compounds, especially those with a hydrophobic component, partition easily into the lipids 

and lipid membranes of organisms and bioaccumulate. Generally a high potential BCF is 

greater than 1000, a moderate potential BCF is less than 100 but greater than 250 and a low 

potential BCF is less than 250. BCF values are presented in section 3.5 of the confidential 

dossier. Organic carbon partition coefficient (Koc) is a measure of the tendency for organic 

substances to be absorbed by soil or sediment. The Koc is substance-specific and is largely 

independent of soil properties. Koc values are presented in section 3.4 of the confidential 

dossier. Octanol/water partition coefficient (Kow) is a measure of the equilibrium concentration 

of a compound between octanol and water that indicates the potential for partitioning into soil 

organic matter. A high Kow indicates a compound which will preferentially partition into soil 

organic matter rather than water. Kow value is inversely related to the solubility of a compound 

in water. Log Kow is used in models to estimate plant and soil invertebrate bioaccumulation 

factors. Table 4 presents logKow values of the compounds. 
MEPC 61/2/11 

Annex, page 7 

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Table 4: Values log Kow for chemicals 

Chemical Name log Kow Reference/comments 

Sodium hypochlorite -0.87 KowWin v.167/EpiSuite (EPA) 

Sodium hypobromite - No data found 

Chlorodibromomethane 1.7 KowWin v.167/EpiSuite (EPA) 

Tribromomethane 1.79 KowWin v.167/EpiSuite (EPA) 

Trichloromethane 1.52 KowWin v.167/EpiSuite (EPA) 

Dichlorobromomethane 1.61 KowWin v.167/EpiSuite (EPA) 

Sodium Bromate -7.18 KowWin v.167/EpiSuite (EPA) 

Monobromoacetic acid 0.43 KowWin v.167/EpiSuite (EPA) 

Dichloroacetic acid 0.52 KowWin v.167/EpiSuite (EPA) 

Dibromoacetic acid 0.7 KowWin v.167/EpiSuite (EPA) 

Bromochloroacetic acid 0.61 KowWin v.167/EpiSuite (EPA) 

Trichloroacetic acid 1.44 KowWin v.167/EpiSuite (EPA) 

Sodium Bisulfite -7.51 KowWin v.167/EpiSuite (EPA) 

5.3 Persistence and identification of the main metabolites in the relevant media 

Due to log Kow and BCF values, it is unlikely that these will be accumulated through the 

aquatic organisms and metabolites. 

5.4 Reaction with organic matter 

Active Substances such as hypochlorous acid and hypobromous acid could react with the 

organic matter naturally present in water and/or other organic substances to yield disinfection 

by-products. Trihalomethanes and haloacetic acids are the most dominant species of 

chlorination by-products. Concentration of free chlorine and bromine, pH, temperature and the 

level of organic matter are parameters that control the production of disinfection by-products. 

For Relevant Chemicals there are no available data on reaction with organic matter. 

5.5 Potential physical effects on wildlife and benthic habitats 

No data were found indicating that Active Substances, Relevant chemicals and Other 

Chemicals could cause potential physical effects to wildlife. 

5.6 Potential residues in seafood 

There is a little possibility for significant residues to accumulate in tissues which could impact 

the consumption of seafood based on low Log POWs and BCFs of the Active Substances, 

Relevant Chemicals and Other Chemicals. 

5.7 Any known interactive effects 

No interactive effects of the Active Substances, Relevant Chemicals and other chemicals 

have been identified. 

6 PHYSICAL AND CHEMICAL PROPERTIES OF THE ACTIVE SUBSTANCES, 

RELEVANT CHEMICALS AND TREATED BALLAST WATER 

Physical and chemical properties of the Active Substances, Relevant Chemicals as well as of 

sodium bisulfite and of treated ballast water are presented in section 6 of the application dossier. 
MEPC 61/2/11 

Annex, page 8 

I:\MEPC\61\2-11.doc 

7 ANALYTICAL METHODS AT ENVIRONMENTALLY RELEVANT 

CONCENTRATIONS 

The analytical methods for each Active Substance, Relevant and Other Chemicals with their 

associated reporting limits are provided in section 7 of the application dossier. 

8 USE OF ACTIVE SUBSTANCE 

8.1 Manner of application 

The treatment process includes two distinctive stages, a primary one that enables the 

separation of coarser suspended materials and relatively larger living organisms in ballast 

water and a secondary one in which disinfection takes place to meet the required biological 

efficacy standard for treated ballast water as stipulated in the BWM Convention. At the 

primary stage of the process, removal of material with size larger than 20 μm is 

accomplished by means of an advanced cyclonic separator made from frictionless material. 

To prevent blocking of the separator from large particles that might pass though the sea 

chests and strainers of the vessel, a 500 μm self cleaning basket filter has been installed 

prior to the separator. This filter is made of glass reinforced plastic while the basket is made 

duplex stainless steel. The benefits offered from the pre-filtering and cyclonic separation 

with the removal of coarse inorganic and organic material present in ballast water is a lower 

disinfectants concentration demand which in turn results in lower concentrations of 

disinfection by-products, less energy and electrodes coatings consumption. 

Electrolysis of ballast water for producing in situ up to 10 mg/L of free active chlorine 

constitutes the second stage of treatment which takes place during ballasting. The products 

of this process flow into the ballast tanks of the vessel, so that the residual oxidants disinfect

any harmful organisms taken onboard. Integral components of the system are the control 

and monitoring equipment that ensure its proper operation as well as the neutralization 

process of treated ballast water prior to its eventual discharge into the sea. The operational 

status of the system is continuously monitored at a central data logger, located into the 

central control panel of the system. Data logging includes the operation status of the system, 

operation, flow and temperature at the electrolytic cell, pressure difference across the selfcleaned filter and the cyclonic separator, the operational status of the neutralizing agent 

dosing pump as well as the chlorine level of the system. The control panel can be positioned 

into the cargo control room of the vessel. All major components including pressure 

difference sensors, flow sensors, chlorine sensors, the neutralizing agent dosing pump, etc., 

described in detail in the section 8 of the confidential dossier, transmit and/or receive their 

output and/or input as 4-20 mA signals. 

During de-ballasting, neutralization of the total residual chlorine takes place by adding 

aqueous solution sodium bisulfite solution.At this mode, the pre-filtering equipment, the 

cyclonic separator and the electrolytic cell of the system is by-passed with the exception of 

the second free chlorine sensor. When de-ballasting begins, the dosing pump of sodium 

bisulfite starts operating at a pre-set value of 20 mg/L. This is based on the worst case 

scenario, which is the need for de-ballasting the water directly after the ballasting process, 

with minimum retention time. Performance tests carried out during the development of the 

system have shown that the biological efficacy required by the D-2 standard of 

the Convention can be achieved in less than 24 hours, however this should be verified during 

the ongoing land-based testing. 
MEPC 61/2/11 

Annex, page 9 

I:\MEPC\61\2-11.doc 

8.2 Process flow description 

The ERMA FIRST Ballast Water Management System is an autonomous fully automatic 

operational unit. The system has two different operational modes, one during ballasting and 

one during the discharge of treated ballast water. The two operation modes are described in 

the following paragraphs. A process and instrumentation diagram is presented in the 

appendix 1 of the confidential dossier. During ballasting, ballast water will pass through 

the 500 μm pre-filter and then into the cyclonic separator. The rich of sediments and coarse 

material underflow stream from the latter will return back into the sea via a drain line. The 

overflow will enter the electrolytic cell. A flow sensor, installed upstream of the cell will provide a 

signal to the cell through the PLC of the system to apply DC current to the electrodes in order 

to initiate the electrochemical process and the production of the Active Substances. A free 

chorine sensor, located downstream of the cell, monitors the free chlorine concentration. 

The production rate of the Active Substances is continuously tuned, to the ballast flow rate 

and the measurement of the free chlorine at the sensor. Depending on the flow rate and the 

free chlorine measurement, the voltage at the cell changes in order to maintain the pre-set 

free chorine concentration. The electrolytic cell of the system has been specifically designed 

to produce the identified Active Substances at temperatures as low as 5o

C and water 

salinity > 0.5 PSU. The ability of the cell to produce free chlorine in such conditions is based 

on the special coating material of its electrodes, and also to its design that enables sufficient 

contact time of chlorides in the water stream with the electrodes, thus providing enough 

contact time to convert into Active Substances. 

Similarly, the electrolytic cell of the system can operate effectively in salinities above 32 PSU, 

due to the fact that water of such salinity results to low electrical resistance and thus the PLC 

of the system will adjust the voltage at the electrodes in such manner in order to keep the 

production of free chlorine at the pre-set values. The whole unit is current driven controlled 

by the chlorine sensor arranging for the set concentration and current applies to the 

electrodes result in a specific amount of Active Substance production. By monitoring the 

operating Amperes on the electrodes of the cell and adjusting the applied voltage, the PLC of 

the system ensures a constant production rate of Active Substances in an extended salinity 

and temperature range. 

A schematic diagram of the operation of the system during ballasting is illustrated: 

Figure 1: Operation mode during ballasting
MEPC 61/2/11 

Annex, page 10 

I:\MEPC\61\2-11.doc 

During de-ballasting, neutralization of the total residual oxidants takes place by adding aqueous 

solution sodium bisulfite solution (38% w/w). At this mode, pre-filtering equipment, the 

cyclonic separator and the electrolytic cell of the system are by-passed with the exception of 

the free chlorine sensor. When deballasting begins, the dosing pump of sodium bisulfite starts 

operating at a pre-set value of 20 mg/L. This is based on the worst case scenario, which is 

the need for de-ballasting the water directly after the ballasting process, with minimum 

retention time. From the stoichiometry of the reaction for the neutralization of 1 mg/L of 

chlorine required 1.5-1.7 mg/L (Metcalf & Eddy, 2003) of sodium bisulfite, i.e. for the 10 mg/L 

of total residual oxidants, 17 mg/L of NaHSO3 required. By using a safety margin of 15% the 

dosing pump of the neutralizing agent will be set at a point to deliver 20 mg/L sodium bisulfite. 

Based on the 38% w/w solution used by the system, the flow rate of the dosing unit will be 

set at 5.3 L/h. A second free chlorine sensor of the de-ballasting system will monitor the total 

chlorine level to ensure a maximum concentration in the discharged water of 0.1 mg/L. 

In case that the total chlorine level at the discharge will reach the 0.1 mg/L then the dosing 

rate of the pump of the neutralization unit will be increased in order to reduce the total 

chlorine level under the 0.1 mg/L set- limit. It is expected that during the ongoing land-based 

testing of the system, a more accurate neutralization dosing rate will be identified. 

A schematic diagram of the operation of the system during ballasting is illustrated: 

Figure 2: Operation mode during deballasting

8.3 Storage, handling and management measures for Other Chemicals 

As mentioned before, aqueous solution of sodium bisulfite will be used for neutralizing ballast 

water prior to its discharge into the sea. The quantity that will be stored on board varies in 

relation to the ballast water capacity of the vessel and should be adequate for the effective 

neutralization of total residual oxidants with minimum refilling requirements. As far as 

engineering controls are concerned, process enclosures, local exhaust ventilation or other 

controls should be used to keep airborne levels below recommended exposure limits. The 

storage means will be placed in a cool, dry, ventilated, protected area, away from sources of 

heat, moisture and incompatibilities. 
MEPC 61/2/11 

Annex, page 11 

I:\MEPC\61\2-11.doc 

The exact location will be specified for each individual vessel according to space availability and 

the applicable statutory and Classification Society rules. Specifically the storage means should 

be protected from water ingress, and maintained structurally in a safe and reliable condition. 

Storage tanks can be constructed from polyethylene, polypropylene, fibreglass-reinforced plastic, 

cross-linked polyethylene (XLPE), or 316 stainless steel to avoid corrosion. The chemical 

will be dosed directly in the deballasting line through a rubber lined carbon steel or stainless 

steel piping. Upon the completion of the deballasting cycle, the piping will be rinsed with water. 

It is recommended that only familiarized personnel should handle the chemical. The manner 

of handling could be integrated into the vessel operational ballasting/deballasting procedures 

while during refilling and handling, the personnel should wear appropriate personal protection 

equipment. The storage means will be kept closed when not in use and all necessary 

equipment for fires, spills, etc., must be readily available. The sodium bisulfite is a 

non-flammable and non-combustible product. In case that the storage means are in contact 

with excessive heat caused by a fire that occurs in that area, sulphur oxides might be 

formed. Exposed containers to flame must be cooled with streams of water until fire 

suppression is achieved. Appropriate self-contained breathing apparatus and full protective 

clothing must be used in order to protect the personnel engaged in the fire-fighting. All other 

personnel must be evacuated from the area while only trained personnel will be allowed to 

approach the containers and the area they are placed. The recommended fire extinguishing 

media is, for small fires, dry chemical, carbon dioxide or water spray while for large fires, dry 

chemical or carbon dioxide must be used. In case of a spill, use of appropriate means must 

be made to collect it so that prevention of its release into the sea is accomplished. Hydrogen 

generated at the cathode of the electrolytic cell has been identified as one of the by-products 

of the second stage of ballast water treatment. Hydrogen is non-toxic but can act as a 

simple asphyxiant by displacing the oxygen in the air. Effects of oxygen deficiency may 

include diminished mental alertness, impaired muscular coordination, faulty judgement, 

depression of all sensations, etc. The whole flow of the ballast water will be treated into the 

electrolytic cell, eliminating the accumulation of hydrogen into the ballast tanks. Monitoring 

of hydrogen generation has been planned to be carried out during both land-based and 

shipboard testing to verify the theoretical calculations presented in section 12. 

9 MATERIAL SAFETY DATA SHEETS AND CLASSIFICATION OF HAZARDS 

To ensure consistency with the classification of hazards in the MSDS of commercially available 

products found for the Active Substances, Relevant Chemicals, and Other Chemicals where 

use of Risk and Safety phrases was made, it was not attempted to provide the "hazard 

statements" and "precautionary statements" that have been introduced in the United Nations 

Globally Harmonized System of Classification and Labelling of Chemicals (GHS) and also 

into the Regulation (EC) No.1272/2008 replacing Risk and Safety phrases. 

Table 5: Hazard Classification 

AS, RC, OC CAS Number Hazard Classification 

Sodium Hypochlorite 

(less than 10% wt. concentration) 

7681-52-9 R31, R36/38 

S28, S36/37/39, S45 

Chlorodibromomethane 124-48-1 R22, R36/37/38 

S26, S37/39 

Tribromomethane 75-25-2 R22, R36/38, R40 

S28A, S45, S61 

Trichloromethane 67-66-3 R20/22, R38, R40 

S36/37 

Dichlorobromomethane 75-27-4 R/22, R36/37/38, R40 

S26, S 36/37/39 

Sodium Bromate 7789-38-0 R38, R41 

S24/25 
MEPC 61/2/11 

Annex, page 12 

I:\MEPC\61\2-11.doc 

AS, RC, OC CAS Number Hazard Classification 

Monobromoacetic acid 79-08-3 R23/24/25, R35, R50 

S36/37/39, S45 

Dichloroacetic acid 79-43-6 R21, R35 

S26, S45, S61 

Dibromoacetic acid 631-64-1 R20/21/22, R34 

S26, S36/37/39, S45 

Bromochloroacetic acid 5589-96-8 R34, R40, R36/37/38 

S26, S27, S36/37/39, S45 

Trichloroacetic acid 76-03-09 R35 

S24/25, S26, S45 

Hydrogen 1333-74-0 R12 

S9, S16, S33 

Sodium Bisulfite 7631-90-5 R22, R31, R41 

S26, S39, S46 

10 RISK CHARACTERIZATION AND ANALYSIS 

10.1 Screening for persistence, bioaccumulation and toxicity 

The Active Substances, Preparations and Relevant Chemicals need to be assessed 

for Persistency, Bioaccumulation potential and Toxicity (PBT). Table 10.1 lists the 

persistence data as determined by Omegam Laboratories in the Netherlands, 

Bioaccumulation potential as bioconcentration Factors (BCF) and the lowest available toxicity 

value. These values were screened against the criteria set by Procedure (G9). 

None of the substances exceed all three PBT criteria. Hence they should not be considered 

as PBT. Toxicity data were collected from the US EPA ECOTOX database and 

supplemented with data from other sources (e.g., IUCLID). When the most sensitive toxicity 

values were based on a flow-through experiment it was excluded in this analysis as such an 

experimental setup is not representative for momentary ballast water discharges. 

Table 6: Persistence, Bioaccumulation and Toxicity of the AS, RC and OCs 

Chemical Name 

Persistence 

Half-life in marine 

water >60 days 

Bioaccumulation 

BCF > 2,000 

Toxicity 

Chronic 

NOEC < 0.01 mg/L 

 Value 

(days) 

Exceeds 

criterion Value (-) Exceeds criterion 

Value 

(mg/L) 

Exceeds 

criterion 

Hypochlorous acid – 

hypochlorite 

(Sodium Hypochlorite) 

0.041 No -2.19 No 0.026 No 

Hypobromous acid – 

hypobromite 

(Sodium Hypobromite) 

- - 1.24 No - - 

Chlorodibromomethane 38 No 9 No 3.2 No 

Tribromomethane 38 No 14 No 2.9 No 

Trichloromethane 38 No 2.9 – 10.35 No 0.006 Yes 

Dichlorobromomethane 38 No 7.0 No 0.78 No 

Sodium Bromate - Yes - 32 No 

Monobromoacetic acid 8.7 No 3.2 No 0.2 No 

Dichloroacetic acid 15 No 3 No 23 No 

Dibromoacetic acid 15 No 0.17 No 69 No 

Bromochloroacetic acid 15 No 3.2 No - - 

Trichloroacetic acid 38 No 0.4 – 1.7 No 1.2 No 

Sodium Bisulfite - Yes 3.2 No 59 No 
MEPC 61/2/11 

Annex, page 13 

I:\MEPC\61\2-11.doc 

11 EVALUATION OF TREATED BALLAST WATER 

11.1 General 

Tests with the ballast water management system were performed in the laboratory of 

IMARES, Den Helder, the Netherlands. A 6 m3

/h model system was placed in a temperature 

control room (15±2°C) and seawater originating from the Oosterschelde, the Netherlands 

and stored in the cellars of the laboratory was used (salinity 30±2‰). 

Picture 1: The model treatment system used in toxicity testing

Production of free chlorine was checked using a colorimetric DPD-method directly after 

production. For comparison, sodium hypochlorite was used in the tests as well. Bioassays 

were initiated immediately after the treated water was processed. Depending on the 

expected toxicity for each organism, two chlorine production settings were used 

(2 and 10 mg/l Cl2). With the treated water, dilution series were made by mixing treated 

ballast water with untreated ballast water. 

Toxicity of sodium bisulphite as a component used to neutralize ballast water during 

deballasting, using the maximum expected concentration as highest concentration in the 

dilution series was also tested. 

11.2 Analysis of total residual oxidants 

Chemical Name 

T=0 

Conc. 

(μg/L Cl) 

T=2 

Conc. 

(μg/L Cl) 

T=5 

Conc. 

(μg/L Cl) 

T=5 

Dechlorinated 

Conc. (μg/L Cl) 

Total available chlorine 9,000 4,500 740 40 
MEPC 61/2/11 

Annex, page 14 

I:\MEPC\61\2-11.doc 

11.3 Disinfection by-products in treated ballast water 

Concentrations in treated ballast water during the toxicity testing as measured by OMEGAM 

Laboratories are listed in the table below. Maximum concentrations are printed in bold face. 

Chemical Substance 

T=0 

Conc. (μg/L)

T=2 

Conc. (μg/L)

T=5 

Conc. 

(μg/L) 

T=5 

Dechlrorination 

Conc. (μg/L) 

Chlorodibromomethane <0.5 8.3 6.0 <0.5 

Tribromomethane 100 180 210 130 

Trichloromethane <0.1 <0.1 <0.1 <0.1 

Dichlorobromomethane <0.5 <0.5 <0.5 <0.5 

Bromate <10 25 48 44 

Monobromoacetic acid 10 21 6.1 6.2 

Dichloroacetic acid <1 <1 <1 <1 

Dibromoacetic acid 120 200 140 150 

Bromochloroacetic acid 5.5 13 6.6 8.1

Trichloroacetic acid <1 <1 <1 <1 

Sulfite (SO3

2-

) <400 <400 720 540 

11.4 Toxicity testing of treated ballast water 

11.4.1 Algal growth inhibition test with Phaeodactylum tricornutum 

Algal growth inhibition by exposure to a sample is determined by the so-called algal growth 

inhibition test according to ISO10253 (2006) and OECD201 (1984) procedures. A known 

quantity of algae (Phaeodactylum tricornutum) from an exponentially growing culture was 

exposed to a dilution series. After 24, 48 and 72 hours, the growth of algae was tested with 

means of fluorescence readings. Each concentration was replicated eight times and every well 

contained a total of 0.25 mL in volume. Each test concentration was inoculated with algae from 

a log-phase growing culture. The start concentration was approximately 10,000 cells/ml, 

determined microscopically. The 96-well plate was incubated under continuous light at 18°C 

and shaken at 130 rpm. Algae were expected to be very sensitive for chlorine; therefore 

production of ballast water has been performed with 2 mg/L settings. 

Table 7: Results of the algal growth inhibition tests with sodium hypochlorite (NaOCl), 

produced ballast water (TRO) and sodium bisulphate (NaHSO3) 

Phaeodactylum 

tricornutum 

NaOCl TRO NaHSO3

(mg/L) (mg/L Cl2) (mg/L) 

NOEC (72h) 0.121 0.030 25 

LOEC (72h) 0.215 0.053 >25 

EC50 (72h) 0.249 (0.174-0.356) 0.158 (0.150-0.166) >25 

11.4.2 Crustacean mortality test with Artemia franciscana

The test was performed in a multiwell testplate using instar II-III larvae of the brine shrimp 

Artemia franciscana, obtained as dried cysts from Microlan B.V., The Netherlands, conforming 

to the Standard Operational Procedure for ARTOXKIT MTM (MicroBioTests Inc. V100603). 
MEPC 61/2/11 

Annex, page 15 

I:\MEPC\61\2-11.doc 

Cysts were incubated in artificial seawater (salinity 35‰) 30 h prior to the start of the tests 

at 25°C with continuous illumination. After 30 h, most cysts were hatched and the larvae 

developed into instar II-III stages. Approximately 50 larvae were transferred to a rinsing well 

containing test medium. From the rinsing well, 10 larvae were transferred to the three test 

wells per concentration/dilution for the test. The well plate was incubated at 25°C in the dark. 

After 24 hours, living and dead larvae in the test wells were counted. 

Artemia were expected not to be sensitive for chlorine, therefore production of ballast water 

(TRO) has been performed with 10 mg/L settings. The highest concentration in the test 

was 9.7 mg/L Cl2 measured directly after production. 

Table 8: Results of the crustacean mortality tests with sodium hypochlorite (NaOCl), 

produced ballast water (TRO) and sodium bisulphate (NaHSO3) 

Artemia franciscana 

NaOCl TRO NaHSO3

(mg/L) (mg/L Cl2) (mg/L) 

NOEC (24h) 0.6 0.97 25 

LOEC (24h) 1.2 4.9 >25 

LC50 (24h) 2.37 (0.05-105.5) 5.60 (4.58-6.84) >25 

11.4.3 Rotifer mortality test with Brachionus plicatilis 

The test applied is commercially available as Testkit at MicroBiotest Innc., Belgium under the 

name ROTOXKIT M and performed according to the Standard Operational Procedure provided 

by the manufacturer. Cysts were incubated in artificial seawater (salinity 20‰) 28 to 30 hours 

prior to the start of the tests at 25°C with continuous illumination. After 28 to 30 hours, most 

cysts were hatched. Approximately 50 larvae were transferred to a rinsing well containing 

test medium. From the rinsing well, 5 larvae were transferred to the six wells per concentration/ 

dilution for the test. The well plate was incubated at 25°C in the dark. After 24h living and 

dead larvae in the test wells were counted. 

Rotifers were expected to be sensitive for chlorine; therefore production of ballast water 

(TRO) has been performed with 2 mg/L settings. The highest concentration in the test 

was 2.0 mg/L Cl2 measured directly after production. 

Table 9: Results of the rotifer mortality tests with sodium hypochlorite (NaOCl), 

produced ballast water (TRO) and sodium bisulphate (NaHSO3) 

Brachionus plicatilis 

NaOCl TRO NaHSO3

(mg/L) (mg/L Cl2) (mg/L) 

NOEC (24h) 1.2 0.50 25 

LOEC (24h) 6 0.66 >25 

LC50 (24h) 2.51 (2.50-2.52) 0.881 (0.861-0.900) >25 

11.4.4 Fish larvae test with Solea solea

The test protocol is based upon OECD203 (1992). Freshly fertilized eggs of the sole (Solea 

solea) were obtained from SOLEA/IMARES, IJmuiden, from a batch produced February, 2010. 

The eggs were incubated at 12-13°C and slight aeration until use in the tests. After 96 h most 

eggs were hatched. The test was performed in 100 mL glass beakers, containing 50 mL of the 
MEPC 61/2/11 

Annex, page 16 

I:\MEPC\61\2-11.doc 

test concentration. Each concentration was replicated 4-fold. To each test beaker 10 yolk-sac 

larvae were transferred. The test beakers were covered with parafilm to prevent evaporation, 

and put away at 12-13°C with a 16 h light – 8 h dark regime. Surviving organisms were 

counted daily in each beaker and dead animals were removed. After 4 days exposure, the 

test was terminated. 

Sole were expected not to be very sensitive for chlorine; therefore production of ballast water 

(TRO) has been performed with high settings. The highest concentration in the test 

was 16.8 mg/L Cl2 measured directly after production. 

Table 10: Results of the fish mortality tests with sodium hypochlorite (NaOCl) 

and produced ballast water (TRO) 

Solea solea NaOCl TRO 

 (mg/L) (mg/L Cl2) 

NOEC (96h) 2.13 2.99 

LOEC (96h) 3.79 5.31 

LC50 (96h) 3.00 (0.770-11.7) 3.23 (0.018-597) 

11.5 Determination of holding time 

As neutralization of the residual oxidants in the treated ballast water stored on board is an 

integral component of the whole process in the ERMA FIRST BWMS, the discharge can be 

carried out as soon as the indented treatment has been accomplished. Toxicity testing that 

was carried out with samples of treated simulated ballast water before and after 

neutralization with sodium bisulfite, demonstrated that the discharge had no adverse effect 

after the neutralization process with the exception of algae, for which the NOEC might be 

lower than the residual chlorine level. Chemical analysis of ballast water treated with 9 mg/L 

of free active chlorine showed that the concentration of total residual chlorine was 0.04 mg/L 

on the 5th day following its electrolytic production and after its has been neutralized. 

11.6 Reaction with organic matter 

As it was discussed in section 2.3 of the confidential dossier, organic matter is a minor but 

important component of seawater affecting among others, the primary production, chemical 

and geological processes in the sea. Organic matter may be broadly categorized as either 

Figure 3: Impact of neutralization to total chlorine concentration 
MEPC 61/2/11 

Annex, page 17 

I:\MEPC\61\2-11.doc 

particulate or dissolved matter. The dissolved organic carbon in the sea is strongly related to 

the balance between the rate at which dissolved organic carbon is formed by decay, 

excretion, etc., and the rate at which it is removed by decomposition or utilization. 

Particulate organic matter includes both living and non-living material in the sea and 

generally refers to particles larger than 0.5 – 1.0 μm diameter although in reality seawater 

contains a continuous range of particle sizes from the smallest colloids up to larger organic 

aggregates (E. Duursma & R. Dawson, 1981). 

The principal source of organic matter in seawater is in situ biological activity such as 

photosynthesis and excretion with external input coming from the land through surface run-off, 

as well as, human activities that produce industrial, agricultural and urban waste water. The 

highest concentrations of organic carbon will usually be found in areas of high productivity or 

in coastal areas under the influence of land-based input where invariably ships perform 

ballasting operations during cargo unloading and transfer. The disinfection by-products 

generated during various reactions between the Active Substances with the organic material 

present in the sea have been outlined in section 2.3 of the confidential dossier. In the first 

stage of treatment immediately after the pre-filtration of ballast water through a self cleaning 

basket filter (> 500 μm), removal of coarse matter with size larger than 20 μm takes place in 

the cyclonic separator. The removal of this material results on the one hand to a lower total 

organic carbon level in the ballast water that will be eventually treated in the second stage 

with a lower disinfectant concentration demand and on the other hand to a reduction of the 

concentrations of disinfection by-products and in particular of trihalomethanes and haloacetic 

acids. The levels of trihalomethanes and haloacetic acids in treated ballast water at the dose 

of 10 mg/L of free active chlorine is presented in section 11.3. The concentrations of these 

groups of substances in treated ballast water will be monitored further during land-based 

testing at NIOZ so that the results are reported in the application for Final Approval. 

11.7 Characterization of degradation route and rate 

Several half-life values are reported for hypochlorous acid and hypochlorite ions, ranging 

from 0.75 up to 1.4 hour. In the presence of organic material, FAC disappears very quickly, 

forming mainly halomethanes and haloacetic acids. Halomethanes are relatively stable as 

they are insensitive towards hydrolysis. As these are volatile, evaporation is a likely 

elimination route in water. A half-life of 38 days is estimated by the PBT-Profiler 

(www.pbtprofiler.net). Haloacetic acids are not very volatile but are more readily degradable 

through other routes than halomethanes. Haloacetic acids are more susceptible towards 

hydrolysis than halomethanes. The PBT-Profiler (www.pbtprofiler.net) estimates half-life 

values ranging from 8.7 up to 38 days in water for these acids. 

Compound Biodegradation rate 

or half-life 

Reference 

Hypochlorous acid – hypochlorite 

(Sodium Hypochlorite) 

1.4 hour (at pH 8) MEPC 60/2/3 

Hypobromous acid – hypobromite 

(Sodium Hypobromite) 

Biodegrades fast MEPC 60/2/3 

Chlorodibromomethane Half-life 

69.951 years at 25°C pH=8 

Epi Suite 

(Hydrowin) 

Tribromomethane Half-life 

340.755 years at 25°C pH=8 

Epi Suite 

(Hydrowin) 

Trichloromethane Half-life 

601.994 years at 25°C pH=8 

Epi Suite (Hydrowin) 

Dichlorobromomethane Half-life 

18.569 years at 25°C pH=8 

Epi Suite (Hydrowin) 

Sodium Bromate Half-life in seawater: 12 hours MEPC 60/2/3 
MEPC 61/2/11 

Annex, page 18 

I:\MEPC\61\2-11.doc 

Compound Biodegradation rate 

or half-life 

Reference 

Monobromoacetic acid Half-life 

Water: 8.7 days 

Soil: 17 days 

Sediment: 140 days 

Air: 25 days 

PBT profile 

Dichloroacetic acid Half-life 

Water: 15 days 

Soil: 30 days 

Sediment: 140 days 

Air: 22 days 

PBT profile 

Dibromoacetic acid Half-life 

Water: 15 days 

Soil: 30 days 

Sediment: 140 days 

Air: 25 days 

PBT profile 

Bromochloroacetic acid Half-life 

Water: 15 days 

Soil: 30 days 

Sediment: 140 days 

Air: 24 days 

PBT profile 

Trichloroacetic acid Half-life 

Water: 15 days 

PBT profile 

11.8 Prediction of discharge and environmental concentrations 

For the calculation of Predicted Environmental Concentrations (PECs), the freely available 

Marine Anti-foulant Model to Predict Environmental Concentrations (MAMPEC v2.0) was 

used. For the current calculations, standard settings of the MAMPEC model were used; 

namely, the OECD-EU harbour (exchange volume 51,117,000 m3

 per tidal period 

of 12.1 hours). Concentrations outside the harbour and in the shipping lane are not resented 

here as they are all lower than the concentrations inside the harbour area). 

Figure 4: MAMPEC Environment input
MEPC 61/2/11 

Annex, page 19 

I:\MEPC\61\2-11.doc 

Table 11: MAMPEC Compound input (* no data available) 

Compound 

Molecular 

Mass 

(g/mol) 

Saturized 

vapour 

pressure 

at 20 or 25 

deg C (Pa) 

Solubility 

at 20/25/30 

deg C 

(gr/m3

) 

Koc 

(10logKoc) 

Melting 

Temp 

(deg C) 

Acid 

dissociation 

constant 

pKa (-) 

Chlorodibromomethane 208.29 7.38E+02 2.70E+03 1.92 -20 * 

Tribromomethane 252.77 7.46E+02 3.10E+03 1.94 8 * 

Trichloromethane 119.38 2.63E+04 7.95E+03 1.81 -63.6 * 

Dichlorobromomethane 163.83 6.67E+03 3.03E+03 1.74 -57 8 

Monobromoacetic acid 138.95 1.59E+01 9.38E+04 1.60 50 2.89 

Dichloroacetic acid 128.94 2.39E+01 1.00E+06 1.88 13.5 1.26 

Dibromoacetic acid 217.84 3.07E+00 2.11E+06 0.176 49 1.48 

Bromochloroacetic acid 173.39 1.87E+01 2.50E+05 0.279 31.5 1.4 

Trichloroacetic acid 163.4 8.00E+00 4.40E+04 2.11 57.5 0.512 

Sodium bromate 150.89 1.00E-10 3.60E+05 * 381 * 

Hypochlorous acid – 

hypochlorite 

(Sodium Hypochlorite) 

74.44 2.00E+03 2.93E+05 0.0627 18 * 

Sodium bisulfite 104.061 7.33E+02 4.20E+05 1.92 * * 

A critical input parameter is the emission that corresponds to the amount of compounds (g) 

discharged per day and defined in model as load. These amounts are calculated from the 

concentration of the substances in the discharged ballast water and the volume being 

discharged. Estimates of discharged volumes range from 50,000 up to 396,000 m3

/day, 

where 50,000m3

/day is likely to be more realistic. We used three scenarios of 50,000, 

100,000 and 200,000 m3

/day as a realistic worst-case assumption. Concentrations 

measured in treated ballast water by OMEGAM (see section 7) after neutralization with 

sodium bisulfite are used as discharged concentrations in the calculations (PECneutralization). 

In MAMPEC the load/emission is calculated (discharge of ships * maximum concentration of 

the compounds). Results from the above equation are presenting in Table 12. Values that 

correspond to three scenarios are in gr/day units while maximum concentration of amounts is 

in μg/L. 

Table 12: MAMPEC Emission input 

 Scenarios :Discharge of ships (m3/day) 

Compound name 

Max Concentration 

of the compounds 

(μg/L) 

50000 100000 200000 

Chlorodibromomethane 8.3 2.50E+01 5.00E+01 1.00E+02 

Tribromomethane 210 6.50E+03 1.30E+04 2.60E+04 

Trichloromethane 0.1 5.00E+00 1.00E+01 2.00E+01 

Dichlorobromomethane 0.5 2.50E+01 5.00E+01 1.00E+02 

Monobromoacetic acid 21 3.10E+02 6.20E+02 1.24E+03 

Dichloroacetic acid 1 5.00E+01 1.00E+02 2.00E+02 

Dibromoacetic acid 200 7.50E+03 1.50E+04 3.00E+04 

Bromochloroacetic acid 13 4.05E+02 8.10E+02 1.62E+03 

Trichloroacetic acid 1 5.00E+01 1.00E+02 2.00E+02 

Sodium bromate 51.9 2.60E+03 5.19E+03 1.04E+04 

Hypochlorous acid – 

hypochlorite 

(Sodium Hypochlorite) 

84 4.20E+03 8.40E+03 1.68E+04 

Sodium bisulfite 701.9 3.51E+04 7.02E+04 1.40E+05 
MEPC 61/2/11 

Annex, page 20 

I:\MEPC\61\2-11.doc 

As indicated in the table below, three measured concentrations had to be converted using 

molar masses, in order to be able to compare these concentrations with the PNEC: 

Table 13: Convert concentrations for comparison 

Chemical name Measured 

as 

Measured concentration 

(T=5 dechlorination) (μg/L) 

PNEC 

based on 

Converted concentration 

(T=5 dechlorination) (μg/L) 

Hypochlorous acid – 

hypochlorite 

(Sodium Hypochlorite) 

Cl 40 NaOCl 51.9 

Sodium bromate BrO3

-

 44 NaBrO3 84 

Sodium bisulfite SO3

2-

 540 NaHSO3 701.9 

The model was running for every compound and the maximum concentration in water was 

defined (μg/L). All data corresponds to PEC values. The following table contains the PECs 

calculated as described above with MAMPEC. 

Table 14: PEC calculations from MAMPEC 

PECneutralized (μg/L)

Chemical Name 50,000 m3/day 100,000 m3/day 200,000 m3/day

Chlorodibromomethane 0.00131 0.00262 0.00525 

Tribromomethane 0.0372 0.745 1.49 

Trichloromethane 0.000217 0.000435 0.000869 

Dichlorobromomethane 0.00119 0.00238 0.00476 

Monobromoacetic acid 0.0121 0.00242 0.0485 

Dichloroacetic acid 0.00375 0.0075 0.015 

Dibromoacetic acid 0.343 0.686 1.37 

Bromochloroacetic acid 0.0177 0.0355 0.071 

Trichloroacetic acid 0.00229 0.00458 0.0917 

Sodium bromate 0.238 0.475 0.95 

Hypochlorous acid – hypochlorite 

(Sodium Hypochlorite) 0.0092 0.0184 0.0368 

Sodium bisulfite 3.21 6.42 12.8 

11.9 Assessment of potential for bioaccumulation 

As indicated in section 10.1 all the Active Substances and Relevant Chemicals have a 

bioconcentration factor of less than 10.35, meaning that it is unlikely that the substances will 

accumulate in the food web. 

11.10 Effects assessment 

In the previous sections the substances were screened for intrinsic PBT properties. In the 

next sections potential effects will be identified based on Predicted Environmental 

Concentrations (PECs) and Predicted No Effect Concentrations (PNECs). 

11.11 Effects on aquatic organisms 

In order to assess effects of the treated ballast water on aquatic organisms, Predicted 

No Effect Concentrations (PNECs) are derived for the Active Substances, Preparations and 

Relevant Chemicals. PNECs are concentration thresholds below which unacceptable effects 
MEPC 61/2/11 

Annex, page 21 

I:\MEPC\61\2-11.doc 

on organisms will most likely not occur. Although there are different approaches to 

determine the PNEC, the procedure described in the Methodology for information gathering 

and the conduct of work of the GESAMP-BWWG is followed here. In this procedure, the 

most sensitive aquatic toxicity endpoint is divided by an assessment factor. The assessment 

factor reflects the degree of uncertainty in extrapolation from laboratory toxicity test data for a 

limited number of species to the "real" environment. 

Assessment factors applied for long-term tests are smaller as the uncertainty of the 

extrapolation from laboratory data to the natural environment is reduced. For this reason 

long-term data are preferred to short-term data. Using these assessment factors and the 

collected toxicity data PNEC values are derived as listed in the table below. Toxicity values 

reported here are from the most sensitive endpoint available. Toxicity experiments using 

flow through exposure systems were not used as most sensitive endpoint as such an 

exposure route is not representative for ballast water treatment. 

Chemical Name Toxicity 

(μg/L) 

Number of chronic 

NOECs in distinct 

taxonomical groups 

BWM.2/Circ.13 

Assessment 

Factor 

PNEC (μg/L) 

Hypochlorous acid – 

hypochlorite 

(Sodium Hypochlorite) 

26 2 100 0.26 

Hypobromous acid – 

hypobromite 

(Sodium Hypobromite) 

- - - - 

Chlorodibromomethane 3,200 1 1,000 3.2 

Tribromomethane 2,900 2 1,000 2.9 

Trichloromethane 5.5 3 10 0.55 

Dichlorobromomethane 780 2 1,000 0.78 

Sodium Bromate 32,000 1 1,000 32 

Monobromoacetic acid 200 1 1,000 0.2 

Dichloroacetic acid 23,000 0 1,000 23 

Dibromoacetic acid 69,000 0 1,000 69 

Bromochloroacetic acid - - - - 

Trichloroacetic acid 1,200 1 1,000 1.2 

Sodium Bisulfite 59,000 0 1,000 59 

11.12 Effects on sediment 

The EU-TGD states that substances with a soil/water partitioning constant normalized to 

organic carbon (Koc) less than 500 – 1,000 l/kg are not likely to adsorb to the sediment. 

As all the Active Substances, Preparations and Relevant Chemicals have a Koc < 196 and 

thus much smaller than 500, they will not likely adsorb to the sediments. 

11.13 Comparison of effect assessment with discharge toxicity 

The results of the chemical analyses of treated seawater show that a direct toxic effect of 

chlorine (FAC) can be expected in the discharged water. Especially for unicellular 

organisms, such as micro algae, the NOEC may be lower than the residual chlorine after 

dechlorination (40 μg/L). In the laboratory tests with treated water performed by IMARES, 

a NOEC of 30 μg/L was found for the marine diatom Phaeodactylum tricornutum 

(see section 11.4). Due to the contact with suspended organic matter in the water, 
MEPC 61/2/11 

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the residual levels of chlorine will rapidly decrease. Therefore, the effect is expected to be 

temporarily. The concentrations of by-products in the discharged water are much lower than 

known toxicity values for these substances. It is not expected that these by-products will 

result in any aquatic toxicity when discharged. 

Toxicity of sodium bisulfite was tested by IMARES with concentrations ranging up 

to 25 mg/L, which is the maximum dosage for neutralization. No effects where observed in 

these experiments for any of the tested concentrations and species (P. tricornutum, 

A. franciscana, B. plicatilis and S. solea) (see section 11.4). Therefore, ecological effects are 

not expected for the bisulfite when the treated ballast water is discharged. 

12 RISK ASSESSMENT 

12.1 Risk to safety of ship 

The potential risk to the safety of the ship and her crew raised by the operation of the ballast 

water treatment system has been evaluated, taking into account the identified risk mitigation 

measures to be implemented and certain requirements of the legislative framework dealing 

with safety and pollution prevention matters. 

During the development of the system, the manufacturer pursued an exchange of views with 

Greek shipping companies with the aim to collect information on a number of issues 

regarding the compartments of the ship where the individual components of the system might 

be installed during from a safety and easy to operate point of view, the minimization of risks 

to the crew posed during surveys and maintenance as well as the changes, if any, to the 

standard procedures performed by the crew in cases of emergency situations. 

12.1.1 Corrosion 

Most data on the effects that the products of electrolyzed seawater might have on the 

corrosion of steel used in storage tanks or their associated piping come from the pulp and 

paper industry in contrast to data referring to ballast water treatment which are comparatively 

less and new. The oxidizing action of hypochlorite ion to the increase of steel corrosion 

depends on the concentration of this agent and a number of environmental parameters such 

as acidity, temperature, etc. It should be noted that the maximum concentration of sodium 

hypochlorite produced by the ERMA FIRST BWMS will not exceed 10 ppm and the materials 

used in the cyclonic separator are synthetic to prevent corrosion basically from seawater 

since the electrolyzed water has no contact at all with it. The electrolytic cell itself and its 

associated connecting piping are fully protected by special coatings against corrosion.

A series of field trials and laboratory tests were performed in 2002 to establish the effects of 

using copper ion and sodium hypochlorite as biocides in ballast water, in the context of a 

study contracted by the Michigan Department of Environmental Quality to BMT Fleet 

Technology to help determine whether these chemicals could be recommended for use as 

biocides in ballast water for ships on the Great Lakes. As far as the use of sodium 

hypochlorite was concerned, the tests attempted to identify its effect on typical coating 

systems of exposure as well as the effect on typical corrosion rates of ship steel when exposed. 

In the same project, tests were conducted using the ASTM standard "Test Method for 

evaluation of Painted or Coated Specimens Subjected to Corrosive Environments 

D 1654 92" and its rating system, to investigate and rate the damage arising from exposure 

to two levels of hypochlorite exposure for four different coating systems using five identical 

test coupons. While no quantifiable analysis is possible with respect to life expectancy from 

laboratory testing, the observation that damage is increased by the presence of chlorine is 
MEPC 61/2/11 

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mitigated by the observation this increase can only be statistically verified in the highly 

aggressive environment. During the life of the ship, the period when tank structure is 

submerged and subject to repeated abrasion i.e. the splash zone of the tank, represents a 

fraction of its total life. This level of aggressivity is also only seen when the ship experiences 

some extraordinary motion when operating in the ballast condition or in the bottom of the 

tanks when residual ballast water is present. 

Protective coating systems are applied in dedicated ballast tanks of ships in service to 

protect the shipbuilding steel from corrosion. Following coating breakdown it is extremely 

difficult, if not impossible, to repair or reinstate the coating to new building standard and 

therefore it is important that such coatings be correctly applied according to sound practices. 

Regulation 3-2 of SOLAS Chapter II-1 referring to corrosion prevention of seawater ballast 

tanks in oil tankers and bulk carriers, require all dedicated water ballast tanks to be coated 

with an efficient corrosion prevention system, such as hard protective coatings or equivalent. 

Performance standards for protective coatings for the ballast tanks in all types of ships have 

been adopted with the resolution MSC.215(82) with detailed specifications and technical 

requirements which intend to provide a 15 years good coating life from its initial application 

to a ship. The specification of a coating or a multi-coat system does not include only the type 

of the individual coating but also steel preparation, surface preparation, surface cleanliness, 

environmental conditions, the application procedure as well as the acceptance criteria and 

inspection. Today, epoxy based coatings are mainly used for the protection of ballast tanks 

of ships and any other systems that might be also applied should comply with the 

performance standards. 

In the context of the same project, and with the aim to establish whether there is any 

increase in corrosion due to the presence of hypochlorite in the concentrations likely to be 

found in a treated ballast tank, up to 90 days long testing was conducted in simulated 

ballast tank conditions with three different environments to replicate conditions in a ballast 

tank, which are the following in terms of increasing aggressivity: (a) in the damp humid space 

replicating an empty ballast tank, (b) fully submerged to replicate a full ballast tank, and 

(c) rotating on a wheel with cyclic immersion into the test solution to replicate the splash zone 

in the head space of a partially full tank. TRC levels were being maintained at 10 ppm 

and 40 ppm. Summarizing the results of the above-mentioned tests, it must be noted that 

there is no significant increase in corrosion rate due to the addition of hypochlorite at 

either 10 or 40 ppm in the short exposure experiments. In the longer exposure experiments 

and less aggressive conditions, mean corrosion rates increased but there is a low confidence 

in the difference of the statistical distribution of these data. 

Corrosion rates of bare steel are increased by the presence of hypochlorite at the biologically 

effective dose rates under constant exposure conditions. However, the amount of corrosion 

increase is not considered significant over the life of a ship due to the relatively small amount 

of time that elevated hypochlorite concentrations would be present. An evaluation of the 

corrosion impacts to the ballast tanks will be conducted during land-based testing, at the 

maximum treatment concentration of 10 mg/L of free active chlorine taking also into account 

the anticipated decay of the residual chlorine. This evaluation will be based on the 

recommendations of the GESAMP-Ballast Water Working Group on corrosion testing 

delivered during its 8th meeting (MEPC 59/2/16). 

This testing should have a time horizon of not less than 6 months and include uncoated 

substrates and marine epoxy coated steel. The testing and the evaluation of both uncoated 

and coated materials will be carried out in accordance with the applicable standards and 

methodologies recommended in the above-mentioned document. 
MEPC 61/2/11 

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12.1.2 Fire and explosion 

In section 2 of the dossier, hydrogen that is generated at the cathode of the electrolytic cell 

has been identified as one of the by-products of the second stage of ballast water treatment. 

Hydrogen is non-toxic but can act as a simple asphyxiant by displacing the oxygen in the air. 

Effects of oxygen deficiency may include diminished mental alertness, impaired muscular 

coordination, faulty judgement, depression of all sensations, etc. The whole flow of the 

ballast water pumped on board a ship will be treated into the electrolytic cell, eliminating the 

accumulation of hydrogen into the ballast tanks. The amount of hydrogen produced at the 

cathode of the electrolytic cell is directly proportional to the amount of electric current that 

passes through the cell. See below: 

Theoretical calculations showed that in the nominal flow rate of 100 m3

/h (based on the 

modular design and construction of the system) and the maximum operating current 

(200 Amps), the concentration of hydrogen in ballast tanks is extremely lower than its lowest 

explosive level, that means the lowest gas concentration that can support an explosion when 

mixed with air (4%). 

The calculation of the amount of electrical charge passing through the seawater, considering 

operating current of 200 Amps for 1 hour, is presented below: 

Moles of electrons that carry the above calculated charge are as follows: 

For every two moles of electrons, a mole of H2 is formed, thus 3.73 mole H2 . See below: 

According to the above calculations, theoretically, 8.06 gr H2 gas per 200 Amps and hour of 

operation are produced by the electrolytic cell. At a treatment flow rate of 100 m3

/hour, the 

hydrogen concentration would be less than 0.1 ppm, a value that is considerably lower low than 

the hydrogen lower explosivity level. However, it is intended that monitoring of hydrogen 

generation be carried out during both land-based and shipboard testing to verify this conclusion. 

12.1.3 Storage and handling of chemical substances 

The only chemical substance that needs to be stored on board is the aqueous solution of 

sodium bisulfite that will be injected into the ballast piping to neutralize the residual oxidants 

present in the treated ballast water before its eventual discharge into the sea. Sodium bisulfite 

solution 38 – 44% can be stored in 316 stainless steel, fibreglass or HDPE tanks while same 

material is recommended for the associated piping, pumps and valves. It must be noted that 

sodium bisulfite is non-flammable and therefore does not present any fire risk. The damage 

of human tissue is the most dangerous characteristic of sodium bisulphite. For that reason, 

protective equipment must be worn which is appropriate to the degree of risk such as safety 

goggles, face shield, hard hat, PVC jacket and pants, PVC gloves, and rubber boots. Normally, 

R 8.314 J / mole K 0.08205 L atm /mole K    

V mole l atm mole K K l      (3.73 ) 0.08205 / 293 89.67

H 2=89.67l 0.0899gr/l=8.06gr/200A/hour 

P V n R T   

720,000 1 . . 96,485C mol e mol e

C

   

60min 60sec 1 200 1 720000

1 1min 1 sec

C Amp hour C hour Amp    
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no respiratory protection is required in handling sodium bisulfite during loading/unloading 

operations. However, during emergency situations, approved sulphur dioxide gas respirators 

or self contained breathing apparatus may be required. Containment under the storage 

tanks placed onboard is recommended. In the event of a leak, sodium bisulphite solution 

may be neutralized with alkali material such as soda ash, caustic soda, lime or limestone. 

12.2 Risks to human health 

Normal procedures for risk assessment for human health is to compare the exposure levels 

to which the population is exposed or likely to be exposed with those levels at which no toxic 

effects are expected to occur. Exposure assessment includes the intensity and the duration 

or frequency of exposure to a substance. Also, the chemical and physical properties 

determine the main exposure routes. From the substances that have been identified in 

section 2 of this dossier, those that are of concern in relation to the exposure risks to the 

crew of the vessel and technical personnel and discussed here are sodium hypochlorite, 

tribromomethane and sodium bisulfite. 

Sodium hypochlorite is produced in situ at 10 mg/L prior to its flow into the ballast tanks. 

The actual disinfection products are hypochlorous acid – hypochlorite ion and hypobromous 

acid – hypobromite ion. The data presented for sodium hypochlorite in section 4 have been 

taken into account to assess the exposure risks. Trihalomethanes and haloacetic acids are 

generated during the reactions of sodium hypochlorite with organic material present in the 

ballast water. The concentrations of the individual substances of these two groups as well as 

sodium bromate measured during the toxicity testing of treated ballast water are provided in 

section 11. Engineer officers or other personnel of the vessel charged with the operation of 

the ballast water treatment system are not expected to be exposed in sodium hypochlorite 

and/or sodium bisulfite during normal operations. 

Risks of exposure might exist in case of failures of the system. Concentrations of sodium 

hypochlorite in aqueous solution more than 12.5% have been reported corrosive for the 

eyes. According to the MSDS of aqueous solutions of sodium bisulfite, contact with it can 

cause skin and eye irritation. Appropriate personal protective means should be used when 

members of the personnel of the vessel or technical personnel deal with its storage or 

handling on board to minimize the potential for acute health effects. 

12.2.1 Free available chlorine 

Free available chlorine is produced in situ at 10 mg/l to its flow into the ballast tanks and will give 

three forms of chlorine, dissolved gas Cl2, hypochlorous acid (HOCl) and hypochlorite ion (OCl-

) 

in equilibrium. The exact concentration of each form is a function of the pH as described in 

section 2.1 of the confidential dossier. Also, hypobromous acid (HOBr) and hypobromite ion 

(OBr-

) are produced as part of the TRO. The data presented for sodium hypochlorite in 

section 4 have been taken into account to assess the exposure risks. It must be noted that 

regulated safety procedures for the production of hypochlorite do not exist in Europe. National 

occupational exposure levels are, therefore, used for determining the exposure evaluation. 

In most European countries, the limit for long term exposure (8 hours TWA) to hypochlorite 

is 1.5 mg/m3

. Some countries use a short term exposure limit (15 minutes STEL) of 3 mg/m3. 

Inhalation exposure of the three forms of chlorine is not likely to occur, except in cases in 

which an aerosol is formed. Volatilization of the hypochlorite ion and the small fraction of 

hypochlorous acid present in the ballast water are very low or even absent. Gaseous chlorine 

can be formed in accidental cases in which strong acids are mixed with the hypochlorite 

solution. The latter is not likely to occur in ballast water treatment. Oral exposure to free 

available chlorine and to chlorinated by-products is only possible for the crew and general 
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public by accidental ingestion. Risk for the crew might only be present in case of failures of 

the system; the general public might be exposed more often but at much lower concentrations. 

Dermal exposure to free chlorine is the route of exposure most likely to occur. 

Engineer officers or other personnel of the vessel charged with the operation of the ballast 

water management system are not expected to be exposed to sodium hypochlorite during 

normal operations. Regardless of the type of the vessel, where the system can be installed, 

the frequency of physical attendance of her machinery spaces by the crew it was considered 

that almost during every ballasting and deballasting operation, a visual observation of the 

ballast water management system may take place. Risks of exposure might exist in case of 

failures of the system, wherein the observers are posed to the highest risk. In case of failure 

observers and crew might be exposed at the highest concentration of hypochlorite (10 mg/L) 

during treatment. 

The general public on the other hand is dermal exposed intermittent as users of coastal 

amenities, beach coastlines and offshore installations and harbours (BWM.2/Circ.13). Worst 

case scenario would be exposure of general public with full contact e.g., through swimming 

in the harbour. This is however not expected to occur. 

Concentrations of sodium hypochlorite in aqueous solution more than 12.5% have been 

reported to be corrosive for the eyes. This is more than 100 times more concentrated than is 

produced during treatment. Corrosiveness to eyes is, therefore, no issue. Rates of 

absorption of hypochlorite through the skin are not available from experimental studies. 

Given the reactivity of the substance to organic materials and other proteinaceous material, 

the potential to be absorbed through the skin is low. In the European Risk Assessment 

report for hypochlorite (European communities, ECB: 2007) a conservative assumption 

of 10% for penetration through the skin is used.

12.2.2 Sodium bisulfite 

The only chemical stored on board in concentrated form is sodium bisulfite 

(38-44% solution). Exposure to humans is possible during storage, at injection to ballast 

water and as surplus in the discharged water. In Europe, the substance is not listed in a 

priority list (as foreseen under Council Regulation (EEC) No 793/93 on the evaluation and 

control of the risks of existing substances). On average, the limit for long term exposure 

(8 hours TWA) to sodium bisulfite is 5 mg/m3

. Sodium bisulfite decomposes at ambient 

temperatures and atmospheric pressure giving sulfur dioxide gas. Exposure limits values for 

sulfur dioxide are 2 mg/m3

 for long term exposure (8 hours TWA) and 5 mg/m3 is used for the 

short term exposure limit (15 minutes STEL). 

Inhalation exposure of sodium bisulfite solution is negligible, only present in cases where a 

mist is formed. The decomposed gaseous fraction sulfur dioxide might be inhaled and pose 

a risk. Both forms causes irritation and sulfite-sensitive individuals may experience a severe 

allergic reaction. Greatest risk for inhalation exposure is while handling the concentrated 

form. Oral exposure to sodium bisulfite is only possible for the crew and general public by 

accidental ingestion. Risk for the crew might be present in case of failures in handling or 

storage; the general public might be exposed more often by the surplus but at much lower 

concentrations. 

Dermal exposure of the substance to crew is a possibility as the substance needs to be 

handled on board. The greatest risk is posed when handling the concentrated form of the 

substance. When handling the concentrated form personal protection should avoid contact 

with the skin or eyes. Prolonged skin exposure may cause mild irritation. To the eyes, 

it tends to cause mild irritation and at prolonged exposure severe burns. The general public 
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is dermal exposed intermittent as users of coastal amenities, beach coastlines and offshore 

installations and harbours (BWM.2/Circ.13). Worst case scenario would be exposure of 

general public with full contact e.g., through swimming in the harbour. 

12.2.3 Tribromomethane 

Tribromomethane and dibromochloromethane are formed as by-products in the process. 

Both substances are not listed in a priority list (as foreseen under Council Regulation (EEC) 

No 793/93 on the evaluation and control of the risks of existing substances). In natural 

circumstances the substances are produced in small amounts by plants in the ocean. 

In water, these chemicals will evaporate to the air and/or be broken down slowly by bacteria. 

Due to the rapid evaporation rate of the substances, inhalation is a likely exposure route. 

Workers may be exposed to vapours of the substances at the ventilation grills on the deck of 

the vessel. The ventilation grills on deck are directly connected to open air, indicating rapid 

ventilation of the vapours. In case of accidental release of vapours in closed areas 

(e.g., machine room) short term exposure may occur. Tribromomethane and 

dibromochloromethane are eliminated from the body fairly quickly. The US Occupational 

Safety and Health Administration (OSHA) set a long term limit of 0.5 ppm for 

tribromomethane (8 hours TWA). No limits have been set for dibromochloromethane due to 

its limited use. The DFG (German Research Foundation) reports a MAK for 

tribromomethane: confirmed animal carcinogen with unknown relevance to humans. 

Very small amounts of the substances may enter the body directly through the skin while 

bathing or swimming. There is no conclusive evidence that tribromomethane or 

dibromochloromethane cause cancer in humans as there is no data of humans exposed 

exclusively to these chemicals. Animal studies showed liver and kidney cancer after long 

term exposure. In the USA, the EPA recommends drinking water containing no more 

than 0.7 ppm of tribromomethane and 0.7 ppm (700 μg/L) of dibromochloromethane. 

The measured concentrations in the treated water did not exceed these limits, posing no risk 

for humans. The highest measured values were 210 μg/L tribromomethane after 2 days 

and 8.3 μg/L of dibromochloromethane after 2 days. 

12.3 Risks to the aquatic environment 

By comparing Predicted Environmental Concentrations (PEC, section 11.8) with Predicted 

No Effect Concentrations (PNEC, section 10.11) potential ecological risks can be identified. 

When the ratio between PEC and PNEC is larger than 1 (in other words: PEC > PNEC) 

ecological effects cannot be ruled out, based on the underpinning worst-case assumptions. 

The table below contains the PEC/PNEC ratios for all Active Substances and Relevant 

Chemicals calculated with the PEC and PNEC values determined in this document. 

 PEC PNEC PEC/PNEC 

50,000 

m3/day 

100,000 

m3/day 

200,000 

m3/day (Literature) 50,000 

m3

/day 

100,000 

m3/day 

200,000 

m3/day 

Chlorodibromomethane 0.00131 0.00262 0.0053 3.2 4.09E-04 8.19E-04 1.64E-03 

Tribromomethane 0.0372 0.745 1.49 2.9 1.28E-02 2.57E-01 5.14E-01 

Trichloromethane 0.000217 0.000435 0.0009 0.55 3.95E-04 7.91E-04 1.58E-03 

Dichlorobromomethane 0.00119 0.00238 0.0048 0.78 1.53E-03 3.05E-03 6.10E-03 

Monobromoacetic acid 0.0121 0.00242 0.0485 0.2 6.05E-02 1.21E-02 2.43E-01 

Dichloroacetic acid 0.00375 0.0075 0.015 23 1.63E-04 3.26E-04 6.52E-04 

Dibromoacetic acid 0.343 0.686 1.37 69 4.97E-03 9.94E-03 1.99E-02 

Trichloroacetic acid 0.00229 0.00458 0.0917 1.2 1.91E-03 3.82E-03 7.64E-02 

Sodium bromate 0.238 0.475 0.95 32 7.44E-03 1.48E-02 2.97E-02 

Hypochlorous acid – 

hypochlorite 0.0092 0.0184 0.0368 0.26 3.54E-02 7.08E-02 1.42E-01 

Sodium bisulfite 3.21 6.42 12.8 59 5.44E-02 1.09E-01 2.17E-01 
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Based on the calculated PEC/PNEC ratios, ecological risks to the aquatic environment are 

not expected due to PEC/PNEC ratios that remain below 1. The calculated PECs are based 

on continuous discharges. 

13 ASSESSMENT REPORT 

Aquatic and mammalian toxicity, the potential for bioaccumulation and persistence in the 

marine environment, as well as the physical and chemical properties of the identified 

Active Substances and Relevant Chemicals produced during the electrolytic disinfection of 

ballast water were assessed to evaluate the environmental risks that might exist when 

discharge of treated ballast water will take place and also the risks to human health and to 

the safety of the vessel and her crew. Toxicity testing of treated ballast water in combination 

with the chemical analyses of the Active Substances in various time intervals showed that 

toxicity was not observed in the discharge 96 hours after treatment for the exposed 

representative species, with the exception of algae, for which the NOEC might be lower than 

the residual chlorine level following the neutralization process. 

The concentration of the identified Relevant Chemicals, generated during the electrolytic 

disinfection of ballast water, were found to be much lower than the respective toxicity values 

for these chemicals. Similarly, toxicity of sodium bisulfite used as neutralization agent in 

concentrations ranging up to the maximum dosage in the system, demonstrated that there 

were no effects for any of the tested species. Toxicity experiments were performed by 

the ISO 9001 certified laboratory of IMARES in the Netherlands, following OECD and 

ISO protocols as closely as possible. The L(E)C50 values determined for sodium 

hypochlorite are comparable with values found in literature as shown in the table below 

(showing only static exposure experiments): 

Table 15: Comparison of toxicity data 

ERMA FIRST BWMS testing results EPA ECOTOX database 

Species L(E)C50 (mg/L) Species L(E)C50 (mg/L) 

P. triconutum 0.249 

(72 h) Diatoms 0.075-0.33 

(24 - 96 h) 

A. franciscana 2.37 

(0.05-106) A. franciscana 5.6 

Brachionus plicatilis 2.51 Brachionus calyciflorus 0.37 

S. solea 3.00 

(96 h) Fish 0.2-10 

(96 h) 

Section 11.8 of the dossier provides an overview of Predicted Environmental Concentrations 

(PECs) as calculated using the MAMPEC v2.0 model. Section 11.11 gives a list of PNECs 

that were used in the risk assessment in section 12.3. Variable PNEC values have been 

reported in literature. Assessment factors are generally designed to obtain a worst-case 

impression of the sensitivity of the receiving environmental compartment towards a toxicant. 

Assessment factors as proposed in BWM.2/Circ.13 were used in this assessment. Major inputs 

for the MAMPEC model were discharged concentrations (μg/L), discharged amounts (m3

/day) 

and half-life values. The PEC/PNEC ratios as presented in section 12.3 indicate that the 

Active Substances and Relevant Chemicals do not pose an ecological risk when discharged. 

Ship's crew charged with the operation of the ballast water treatment system or other 

personnel dealing with its maintenance are not expected to be exposed in the Active 

Substances or the neutralizing agent used during normal operations. Risks of exposure 

might exist in case of failures of the system. 

___________