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

E

MARINE ENVIRONMENT PROTECTION 

COMMITTEE 

61st session 

Agenda item 2 

MEPC 61/2/2

17 March 2010

 Original: ENGLISH

HARMFUL AQUATIC ORGANISMS IN BALLAST WATER 

Application for Final Approval of the Special Pipe Hybrid Ballast Water Management 

System combined with Ozone treatment version (SP-Hybrid BWMS Ozone version) 

Submitted by Japan 

SUMMARY 

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

the application for Final Approval of the Special Pipe Hybrid Ballast 

Water Management System combined with Ozone treatment 

version (SP-Hybrid BWMS Ozone version) under 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: 7.1.2.4 

Action to be taken: Paragraph 7 

Related documents: BWM/CONF/36; MEPC 53/24/Add.1; MEPC 55/2, MEPC 55/2/16; 

MEPC 57/2/10; MEPC 59/2/1, MEPC 59/2/16, MEPC 59/24 and 

BWM.2/Circ.13 

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 Convention shall be approved by 

the Organization. 

2 Japan herewith submits an application for Final Approval according to the Procedure 

for approval of ballast water management systems that make use of Active Substances (G9). 

This Procedure stipulates the required information (MEPC 57/21, annex 1, paragraph 4.2.1) 

which, according to section 6, should be evaluated by the Organization. In accordance with 

the Methodology for information gathering and conduct of work of the GESAMP-BWWG 

(BWM.2/Circ.13), the document in the annex contains the non-confidential part of the 

manufacturer's application dossier including the following: 
MEPC 61/2/2 

Page 2 

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

.1 summary of the research conducted for the Special Pipe Hybrid Ballast 

Water Management System combined with Ozone treatment version 

according to Procedure (G9); 

.2 reference list; and 

.3 quality control certificate on the tests performed. 

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

Working Group with the understanding of confidential treatment. 

3 "Special Pipe Hybrid Ballast Water Management System combined with Ozone 

treatment version" (SP-Hybrid BWMS Ozone version) is the same system as the one called 

the "Special Pipe Ballast Water Management System (combined with Ozone treatment)" 

which was reviewed for Basic Approval during the second meeting of the GESAMP-BWWG 

in May 2006 and was subsequently granted Basic Approval at MEPC 55 in October 2006. 

Its name was slightly changed for the purpose of future commercialization. 

4 The application is submitted by the manufacturer, Mitsui Engineering & Shipbuilding Co., Ltd. 

instead of the Japan Association of Marine Safety, that proposed the original one as a 

coordinator of the project development at that time. 

5 This application is now made for Final Approval of SP-Hybrid BWMS Ozone version. 

A previous application was reviewed at the eighth meeting of the GESAMP-BWWG in 

February 2009. However, the GESAMP-BWWG pointed out several deficiencies with the 

application and decided not to recommend Final Approval (MEPC 59/2/16). 

The GESAMP-BWWG's recommendation was endorsed by MEPC 59 in July 2009. Following 

additional tests, taking into consideration the comments made by the GESAMP-BWWG, 

an application for Final Approval is resubmitted along with the assessment report on the 

tests. 

6 The receiving competent authority in Japan has verified the application dossier and 

believes it to satisfy the data requirements of Procedure (G9) adopted by 

resolution MEPC.169(57). 

Action requested of the Committee 

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

appropriate. 

*** 
MEPC 61/2/2 

Annex, page 1 

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

ANNEX 

NON-CONFIDENTIAL INFORMATION ON THE 

SPECIAL PIPE HYBRID BALLAST WATER MANAGEMENT SYSTEM COMBINED WITH 

OZONE TREATMENT VERSION (SP-HYBRID BWMS OZONE VERSION) 

Contents 

1 INTRODUCTION

1.1 Application process with Procedure (G9) fo the "Special Pipe Hybrid Ballast Water 

Management System combined with Ozone treatment version (SP-Hybrid BWMS 

Ozone version)" 

1.2 Comments made by the GESAMP-BWWG (MEPC 59/2/16, annex 4) on the 

previous application for Procedure (G9) Final Approval (MEPC 59/2/1)" 

1.3 Constitution of application (Final Approval) 

1.4 Conditions of system application 

1.5 Changes from the previous application for Final Approval (MEPC 59/2/1) 

1.6 Conclusion of Final Assessment Report 

2 APPLICATION DATA SET 

2.1 Identification of the Substance or Preparation (G9: 4.1) 

2.1.1 Preparations (G9: 4.2.2) 

2.1.2 Active Substances 

2.1.3 Relevant Chemicals (G9: 2.1.4) 

2.1.4 Other Chemicals 

2.2 Data on effects on aquatic plants, invertebrates and fish, and other biota, including 

sensitive and representative organisms (G9:4.2.1.1) 

2.2.1 Acute aquatic toxicity 

2.2.2 Chronic aquatic toxicity 

2.2.3 Endocrine disruption 

2.2.4 Sediment toxicity 

2.2.5 Bioavailability/biomagnification/bioconcentration 

2.2.6 Food web/population effects 

2.3 Data on mammalian toxicity (G9: 4.2.1.2) 

2.3.1 Active Substance 

2.3.2 Relevant Chemicals 

2.4 Data on environmental fate and effect under aerobic and anaerobic conditions 

 (G9: 4.2.1.3) 

2.4.1 Modes of degradation (biotic; abiotic) 

2.4.2 Bioaccumulation, partition coefficient, octanol/water partition coefficient 

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

 (ballast water, marine and fresh water) 

2.4.4 Reaction with organic matter 

2.4.5 Potential physical effects on wildlife and benthic habitats 

2.4.6 Potential .residues in seafood 

2.4.7 Any known interactive effects 

2.5 Physical and chemical properties for the Active Substances and preparations and 

treated ballast water, if applicable (G9: 4.2.1.4) 

2.6 Analytical methods at environmentally relevant concentration (G9: 4.2.1.5)
MEPC 61/2/2 

Annex, page 2 

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

3 USE OF THE ACTIVE SUBSTANCE 

3.1 Summary of SP-Hybrid BWMS Ozone version 

3.1.1 Components and outline 

3.1.2 Characteristics 

3.2 Manner of application (G9: 4.2.6 and 7) 

3.2.1 Maximum dosage concentration of Ozone 

3.2.2 Holding time 

3.2.3 Maximum allowable discharge concentration of the Relevant Chemicals 

3.2.4 Handling, use, storage, and transport of the chemicals 

3.2.5 Procedures and use of the system 

3.2.6 Risk management measures in case of emergency 

4 MATERIAL SAFETY DATA SHEETS (G9: 4.2.7) 

5 RISK CHARACTERIZATION 

5.1 Screening for persistence, bioaccumulation and toxicity (G9: 5.1) 

5.1.1 Persistence (G9: 5.1.1.1) 

5.1.2 Bioaccumulation (G9: 5.1.1.2) 

5.1.3 Toxicity test (G9: 5.1.2.3) 

5.1.4 Do the Ozone and Relevant Chemicals meet all three criteria for PBT? 

6 EVALUATION OF THE TREATED BALLAST WATER (G9: 5.2) 

6.1 Tests of the treated ballast water implemented for reapplication of Final Approval 

6.1.1 Summary of tests 

6.1.2 Test facility 

6.1.3 Quality control of test 

6.2 Full-scale land-based acute toxicity test (G9: 5.2.2) 

6.3 Full-scale land-based chronic toxicity test (G9: 5.2.1) 

6.4 Corrosion tests 

6.5 Long-term performance test of Discharge Water Treatment Tank 

6.6 Life determination test for activated carbon filled in Discharge Water Treatment Tank 

(DWTT) 

6.7 Automatic measurement test of TRO in ballast water discharge by TRO monitor 

6.8 Determination of holding time 

6.9 Risk characterization and analysis 

6.9.1 Reaction with organic matter (G9: 4.2.1.3) 

6.9.2 Characterization of degradation route and rate (G9: 5.3.5) 

6.10 Prediction of discharge and environmental concentrations 

6.11 Assessment of potential for bioaccumulation 

6.12 Effects assessment 

6.13 Effects on aquatic organisms 

6.13.1 Estimated PNEC 

6.13.2 PEC/PNEC ratio 

6.14 Effects on sediment 

6.15 Comparison of effect assessment with discharge toxicity 
MEPC 61/2/2 

Annex, page 3 

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

7 RISK ASSESSMENT 

7.1 Risk to safety of ship 

7.1.1 Increased corrosion 

7.1.2 Fire and explosion 

7.1.3 Storage and handling of the substances 

7.1.4 Contact with, or inhalation of, process products 

7.1.5 Noise 

7.2 Risk to human health 

7.2.1 Health effects in humans (G9: 5.3.12) 

7.2.2 Human Exposure Scenario (HES) (G9: 6.3.3) 

7.2.3 Conclusion 

7.3 Risk to the aquatic environment 

8 CONCLUSION 

REFERENCES 

APPENDIX 1 STATEMENT 

APPENDIX 2 QUALITY ASSURANCE STATEMENT 
MEPC 61/2/2 

Annex, page 4 

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

1 INTRODUCTION 

1.1 Application process with Procedure (G9) for "Special Pipe Hybrid Ballast 

Water Management System combined with Ozone treatment version 

(SP-Hybrid BWMS Ozone version)" 

"Special Pipe Hybrid Ballast Water Management System combined with Ozone treatment 

version (SP-Hybrid BWMS Ozone version)" is the new name of "Special Pipe Ballast Water 

Management System (combined with Ozone treatment)". In the second meeting of the 

GESAMP- Ballast Water Working Group (GESAMP-BWWG) held from 22 to 26 May 2006, 

the System was evaluated in accordance with the "Procedure for approval of ballast water 

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

MEPC.126(53). Basic Approval was granted at MEPC 55 held from 9 to 13 October 2006. 

An application is now made for Final Approval of SP-Hybrid BWMS Ozone version. 

A previous application was reviewed at the eighth meeting of the GESAMP-BWWG held 

from 16 to 21 February, 2009. However, the GESAMP-BWWG pointed out several 

deficiencies with this BWMS application and decided not to recommend Final Approval 

(MEPC 59/2/16). This was agreed at MEPC 59 held from 13 to 17 July, 2009. Following 

additional tests taking into consideration the comments made by the GESAMP-BWWG, an 

application for Final Approval is resubmitted along with the Assessment report on the tests. 

1.2 Comments made by the GESAMP-BWWG (MEPC 59/2/16, annex 4) on the 

previous application for Final Approval (MEPC 59/2/1)

The following comments were made by the GESAMP-BWWG: 

.1 Maximum TRO (Total Residue Oxidants) discharge concentration 

of 0.69 mg/L as O3 (1.02 mg/L as Cl2) is an unacceptably high level for 

marine environmental safety. 

.2 Performance of Discharge Water Treatment Tank (henceforth DWTT) to 

ensure maximum discharge concentration should be examined for a long 

period in full-scale test facility equipped with automatic control system 

by TRO monitor. TRO maximum discharge concentration should be 

reduced to less than 0.2 mg/L as Cl2. 

.3 Ecosystem toxicity test and DWTT performance test should be 

implemented in full-scale test by using test effluent with standard TRO 

concentration (less than 0.02 mg/L (as Cl2)) and also with TRO analytical 

method to achieve accurate TRO detection level and should be assessed. 

.4 A long-term test on uniform and local corrosion using predicted treatment 

concentration of Active Substances should be implemented and corrosion 

effect should be assessed. 

.5 Toxicity test on aquatic organisms should be implemented within a short 

period (12 hours) from sampling until exposure to organisms and analysis in 

order not to cause an underestimate, taking into account TRO dissolution. 

.6 Toxicity tests should be implemented in a full-scale land-based test facility 

controlled automatically by TRO monitor strictly under conditions 

of Guidelines (G8) test water. 
MEPC 61/2/2 

Annex, page 5 

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

.7 TRO including TRO dissolution rate to be adopted for the MAMPEC model 

should be properly defined. 

.8 Assessment factor for HES should be scrutinized further. 

.9 In case stainless steel is used to protect system components from 

corrosion, its type and grade is not identified. 

The responses to comments of the GESAMP and positions in this paper are listed in 

Table 1.2-1. 

Table 1.2-1: List of comments made by GESAMP-BWWG and corresponding tests, 

assessments and paragraphs of this document 

Comment 

in MEPC 

59/2/16, 

annex 4 

Comment Response in this 

application 

Result of 

response 

Corresponding 

paragraph of 

this document 

0.2.1.1 

5.1 

9.3.1 

Maximum TRO discharge 

concentration of 0.69 mg/L 

as O3 (1.02 mg/L as Cl2) is 

an unacceptably high level 

for marine environmental 

safety. 

TRO removal 

performance by the 

DWTT was reinforced 

and various tests were 

conducted in the 

full-scale land-based test 

facility adopting accurate 

measure/monitor 

method (DPD method). 

Result of various 

tests showed a low 

level of maximum 

discharge 

concentration as 

0.16 mg/L (as Cl2). 

1.3.4, 

1.3.6, 

6.1 

0.2.2 

0.3.2 

5.2 

5.5 

5.9 

5.11 

Performance of DWTT to 

ensure maximum discharge 

concentration should be 

examined for a long period 

in full-scale test facility 

equipped with automatic 

control system by TRO 

monitor. TRO maximum 

discharge concentration 

should be reduced to less 

than 0.2 mg/L as Cl2. 

Same as above. Same as above. 

1.3.4, 

1.3.6, 

6.1 

6.5 

0.2.3 

5.2 

5.3 

5.5 

9.3.2 

Ecosystem toxicity test and 

DWTT performance test 

should be implemented in 

full-scale test by using test 

effluent with standard TRO 

concentration 

(less than 0.02 mg/L 

(as Cl2)) and also with TRO 

analytical method to 

achieve accurate TRO 

detection level and should 

be assessed. 

Same as above. 

Result of various 

tests using test 

effluent with 

maximum TRO 

0.02 mg/L (as Cl2) 

showed a level of 

maximum TRO 

discharge 

concentration as low 

as 0.16 mg/L 

(as Cl2). 

1.3.1, 

1.3.2, 

1.3.4, 

6.1, 6.2, 

6.3 

0.2.4 

5.4 

7.2.2 

7.2.3 

9.1.1 

9.1.2 

A long-term test on uniform 

and local corrosion using 

predicted treatment 

concentration of Active 

Substances should be 

implemented and corrosion 

effect should be assessed. 

Long term corrosion 

effect test on each 

coating and material was 

conducted at 2 

temperatures using the 

test water treated with 

4 mg/L Ozone and 

corrosion effect was 

evaluated. 

Test result showed 

no corrosion effect 

on any coating or 

material. 

1.3.3, 

6.1, 6.4 
MEPC 61/2/2 

Annex, page 6 

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

Comment 

in MEPC 

59/2/16, 

annex 4 

Comment Response in this 

application 

Result of 

response 

Corresponding 

paragraph of 

this document 

0.3.1 

5.7 

5.8 

Toxicity test on aquatic 

organisms should be 

implemented within a short 

period (12 hours) from 

sampling until exposure to 

organisms and analysis in 

order not to cause 

underestimate, taking into 

account TRO dissolution. 

TRO measurement for 

each test was conducted 

immediately after 

treatment and TRO 

analysis at time of 

organism exposure in 

toxicity test was 

achieved in 10 hours 

after treatment. 

Results of various 

tests showed 

0.16 mg/L (as Cl2) for 

maximum TRO 

concentration in the 

ballast water 

discharge and found 

neither acute nor 

chronic toxicity. 

6.2, 6.3 

0.3.3 

5.2 

5.6 

5.10 

Toxicity tests should be 

implemented in a full-scale 

land-based test facility 

controlled automatically by 

TRO monitor strictly under 

conditions of 

Guidelines (G8) test water. 

Toxicity tests were 

implemented in the 

full-scale land-based test 

facility automatically 

controlled by precise 

measure/monitor 

method (DPD method). 

Same as above. 

1.3.6, 

6.2, 6.3, 

6.7 

0.3.4 

8.2.4 

TRO including TRO 

dissolution rate to be 

adopted for MAMPEC 

model should be properly 

defined. 

PEC for TRO in ballast 

water was predicted by 

use of property data of 

bromate ion, main 

component of TRO. 

PEC for TRO as 

bromate ion was 

predicted 

as 0.020 μg/L. 

6.10.3.3.2 

0.4.3 

7.3.2 

7.3.3 

7.3.5 

9.2.2 

Assessment factor for HES 

should be scrutinized 

further. 

Taking into 

consideration the latest 

information, HES was 

reevaluated. 

Reevaluation result 

of HES showed low 

risk level for both 

Ozone and Relevant 

Chemicals, which 

cause no effect on 

human health. 

7.2 

7.2.1.1 In case stainless steel is 

used to protect system 

components from corrosion, 

its type and grade is not 

identified. 

Grade was identified. Grade was identified. 3.2.5.6.3, 

7.1.1.2.2 

1.3 Constitution of application (Final Approval) 

This application for Final Approval has been developed in accordance with the Methodology 

for information gathering and the conduct of work of the GESAMP-BWWG (BWM.2/Circ.13). 

The additional tests have been implemented for reapplication for Final Approval. 

The following is the summary of tests: 

 .1 Full-scale land-based acute toxicity test 

The acute toxicity test was performed using a full-scale BWMS 

(capacity 200 m3

/h) and a Discharge Water Treatment Tank (DWTT) with a 

changed activated carbon filling with a high performance of oxidant 

removal. The test system was equipped with automatic control by TRO 

monitor and the tests were conducted using test effluent in accordance with 

Guidelines (G8) conditions of seawater and brackish water and also using 

treated ballast water (holding time; 0 h) after post-treatment as exposure 

water. As in previous acute toxicity tests, no acute toxicity was found even 

for undiluted ballast water. 
MEPC 61/2/2 

Annex, page 7 

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

 .2 Full-scale land-based chronic toxicity test 

The chronic toxicity tests were conducted in the same test system and test 

effluent as in the full-scale land-based acute toxicity test using exposure 

water of treated ballast water (holding time; 0 h) after post treatment in 

the DWTT. As in previous chronic toxicity tests, no chronic toxicity was 

found even for undiluted ballast water. 

 .3 Corrosion test 

The following two assessment tests were conducted in the same full-scale 

test system as the full-scale land-based acute toxicity test using exposure 

water of presumably most corrosive test water of this BWMS immediately 

after Ozone injection: 

.1 corrosion test for ballast tank coatings; test to examine adhesion 

reduction and deterioration of coated film in ballast tank; and 

.2 corrosion test for uncoated materials; test to examine corrosion of 

materials in contact with treated ballast water. 

After immersing various test pieces in treated ballast water for 97 days 

at 40°C to maximize the corrosion rate, it was found that none of the test 

pieces showed any serious corrosion. Therefore, it was confirmed that this 

BWMS causes corrosion effect to the hull within the allowable range. 

 .4 Long-term performance test for activated carbon filled in Discharge Water

 Treatment Tank ( DWTT)

 Performance of the DWTT in removing TRO and Relevant Chemicals was 

examined by operating the same test system as the aforementioned 

full-scale land-based acute toxicity test without daily stoppage extending to 

a total of 508 hours operation. Replacement of activated carbon with the 

material with excellent oxidant removal performance clearly improved the 

result. Bromoform concentration increased from 0.0014 mg/L at the 

beginning of operation to 0.034 mg/L after 508 hours operation and showed 

a slight deterioration in removal performance, however, a certain 

performance of removal was assured. The discharge concentration of 

bromate ion as the oxidant started with 0.033 mg/L at the beginning 

and 0.025 mg/L was observed after 508 hours (maximum 0.082 mg/L), 

which proved a high level of removal performance. The TRO measured by 

the sensor, which represents the total amount of oxidant immediately after 

discharge, did not increase with elapsed time and moved within a range 

from 0.06 mg/L to a maximum of 0.16 mg/L (as Cl2), which also assured the 

maintenance of a high-level removal performance. Therefore, replacement 

of activated carbon to another product with superior oxidant removal 

performance gives assurance that the DWTT maintains high removal 

performance particularly on oxidant. With reference to the life of activated 

carbon filled in the DWTT, a test to predict this life was implemented. 

 .5 Life determination test for activated carbon (WH2c8/32L) filled in Discharge 

Water Treatment Tank (DWTT) 
MEPC 61/2/2 

Annex, page 8 

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

TRO in effluent was measured at multiple positions in the DWTT during the 

aforementioned long-term performance test for activated carbon filled in the 

DWTT and from the chronological variation of reduction of removal 

performance, the time when TRO concentration in the ballast water 

discharged from DWTT reached 0.2 mg/L (as Cl2) was assumed to 

correspond to the life of activated carbon. It was confirmed that in the case 

of operation during a real voyage the life would exceed 2000 hours. 

 .6 In the tests listed in the above subparagraphs 1 to 5, the TRO concentration 

in the ballast water immediately after discharge from the DWTT was always 

under surveillance by sensor (CL17; DPD method, range of 

measurement 0.035 mg/L - 5 mg/L (as Cl2)). If TRO more than 0.2 mg/L 

(as Cl2) is detected, the system automatically stops. The measured TRO 

was less than 0.2 mg/L (as Cl2) in all the tests and the maximum measured 

value was 0.16 mg/L (as Cl2). Furthermore, more than 60% of the 

measurements were below 0.1 mg/L (as Cl2). As the ballast water treated 

by the DWTT immediately after Ozone injection without storage was used 

for the series of tests, in actual practice TRO is likely to be less 

than 0.1 mg/L (as Cl2). 

1.4 Conditions of system application

SP-Hybrid BWMS Ozone version should be applied under the following conditions. 

This application for Final Approval requires review and permission with reference to the use 

of BWMS under these conditions. 

.1 Ballast water required for treatment: 

 Sea and brackish water containing bromide ions is used. 

.2 Times of ballast water treatment: 

 It is treated only once on ballasting. 

.3 Concentration of Active Substance (Ozone) when in use: 

 Ozone as Active Substance is injected on ballasting in such manner to 

achieve the concentration of 3 mg/L in the ballasting water. 

.4 Holding time: 

 Holding time following ballast water treatment is not set up. Ballast water 

can be discharged immediately after treatment. 

.5 Operation of Discharge Water Treatment Tank (DWTT): 

 At the time of the ballast water discharge, TRO concentration prior to 

discharge (prior to DWTT) was under surveillance by TRO monitor. If TRO 

exceeds 0.2 mg/L (as Cl2), discharge follows after removal of Relevant 

Chemicals by the DWTT. Meantime, if TRO is less than 0.2 mg/L (as Cl2), 

discharge follows without going through DWTT. 

.6 The maximum allowable discharge concentration of Relevant Chemicals: 

 The maximum allowable discharge concentration of Relevant Chemicals at 

time of discharge following removal by the DWTT is 0.082 mg/L for bromate 

ion, 0.22 mg/L for bromoform and 0.2 mg/L (as Cl2) for TRO. 
MEPC 61/2/2 

Annex, page 9 

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

 Although the maximum discharge concentration of bromoform 

was 0.034 mg/L observed in tests of ballast water discharge, it was decided 

to adopt 0.22 mg/L as the maximum allowable discharge concentration 

generated by Ozone injection namely the value prior to post-treatment of 

DWTT. This was decided because a slight decrease in removal 

performance by DWTT was observed as time elapsed. 

 With reference to TRO, even in case of post treatment by DWTT 

immediately after Ozone injection which is unlikely to occur in real 

operation, most of the measurements of the ballast water discharge showed 

concentrations less than 0.1 mg/L (as Cl2) and the maximum was 0.16 mg/L. 

Therefore, it was decided to adopt 0.2 mg/L (as Cl2) as the maximum 

allowable discharge concentration. 

1.5 Changes from the previous application for Final Approval (MEPC 59/2/1) 

Changes from the previous application (MEPC 59/2/1, appendix 18) for Final Approval of this 

BWMS are as follows: 

.1 Various tests including toxicity tests and corrosion tests were implemented 

in a full-scale land-based test facility (200 m3/h) and necessary evaluation 

was performed for the treated ballast water. 

.2 Based on data obtained in the aforementioned tests, risk assessment was 

performed again. 

The following changes have been made to this BWMS to cope with changes of application: 

.1 Type of activated carbon filled in DWTT 

 By changing from the previous type to an activated carbon with higher 

performance, the oxidant removal performance of the DWTT was 

reinforced. 

.2 Change of monitor method for TRO concentration in ballast water 

discharge: 

 TRO concentration after the DWTT was put under surveillance of TRO 

monitor which was set up a criterion as 0.2 mg/L (as Cl2) defined as the 

maximum allowable discharge concentration. 

1.6 Conclusion of final assessment report 

The SP-Hybrid BWMS Ozone version uses Ozone, which is a strong oxidizing agent, as an 

Active Substance. Ozone reacts with ballast water to generate the Relevant Chemicals; 

bromate ion, bromoform and Total Residual Oxidants (TRO) in the ballast water. 

This BWMS has been enhanced (compared with the BWMS described in the previous 

application) by improving the oxidant removal performance of Discharge Water Treatment 

Tank (DWTT) and includes thorough safety measures for Ozone, which are put in place 

onboard a vessel so that the safety of the vessel and her shipboard personnel is completely 

secured. Furthermore, as the concentration of generated Relevant Chemicals is reduced 

through the Discharge Water Treatment Tank (DWTT), the potential impact on general public 

health and on the environment in the ambient waters of the ballast discharge is deemed to 

be almost negligible so that environmental safety is secured. Therefore, this system is 

considered to deserve Final Approval under Procedure (G9). 
MEPC 61/2/2 

Annex, page 10 

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

2 APPLICATION DATA SET 

2.1 Identification of the Substance or Preparation (G9: 4.1) 

2.1.1 Preparations (G9: 4.2.2) 

It is the same as previous application (MEPC 59/2/1). 

A sequence of processes is conducted during uptake of ballast water by operation of various 

items of equipment which are all installed onboard. 

Therefore, no additional preparations are required and no Ozone storage onboard is 

necessary to operate the system. 

2.1.2 Active Substances 

The Active Substance in SP-Hybrid BWMS Ozone version is Ozone as described in above 

section. 

Ozone information is the same as previous application (MEPC 59/2/1). 

2.1.3 Relevant Chemicals (G9: 2.1.4) 

Relevant Chemicals are as follows (the same as previous application (MEPC 59/2/1): 

.1 Bromate ion which is the final product by the reaction of seawater and 

Ozone; 

.2 Bromoform which may be generated finally by the reaction of organic matter 

in seawater and Ozone; and 

.3 TRO which are generated by the reaction of seawater and Ozone, including 

all undetected intermediate oxidants. 

Table 2.1-1 shows the concentration of chemical substances in the pre-treatment influent 

water as well as post-treatment discharge water. During the tests to measure relevant 

matters in ballast water discharge above, all tests were re-done using the enhanced DWTT 

and the results include measurements by the TRO monitor during all the tests. 

Table 2.1-2 showed additional information on Relevant Chemicals of this BWMS. 

Comprehensive testing gave these maximum concentrations of Relevant Chemicals in the 

ballast water discharge: bromate ion: 0.082 mg/L, bromoform: 0.034 mg/L and 

TRO 0.16 mg/L (as Cl2). 

As the DWTT performance of removing bromoform shows the tendency of a slight reduction 

according to the elapsed time, the maximum concentration of 0.22 mg/L which was 

generated by the Ozone injection is defined as the maximum discharge concentration. 
MEPC 61/2/2 

Annex, page 11 

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

Table 2.1-1(1): Concentration of chemical substances in pre-treatment influent water 

and in post-treatment ballast water discharge in full-scale land-based 

acute toxicity test (seawater case) 

Items Untreated influent 

water*5 Treated discharge 

water*6

Water Temperature (°C)*1

Salinity (PSU)*1

pH*1 

Dissolved oxygen (mg/L)*1

POC (mg/L)*2

DOC (mg/L)*2

TSS (mg/L)*2

23.9 – 27.5 

32.5 – 34.0 

 8.2 

6.0 – 7.0 

1.0 – 3.8 

2.8 – 3.8 

24 – 40 

23.9 – 27.7 

32.3 – 33.9 

8.2 

9.5 – 14.6 

<0.1 – 0.2 

1.6 – 2.0 

1 – 3 

Bromate ion (mg/L)*3

THM Bromoform (mg/L)*3

 Chloroform (mg/L)*3

Bromodichlotomethane (mg/L)*3

 Dibromochloromethane (mg/L)*3

TRO (mg/L as Cl2)*4

<0.01 

0.0002 – 0.0003 

<0.0001 

<0.0001 

<0.0001 

0.01 – 0.02 

0.04 – 0.07 

0.0058 – 0.029 

<0.0001 

<0.0001 

0.0004 – 0.0006 

0.01 – 0.05 

Brackishwater case 

Items Untreated influent 

water*5 Treated discharge 

water*6

Water Temperature (°C)*1

Salinity (PSU)*1

pH*1

Dissolved oxygen (mg/L)*1

POC (mg/L)*2

DOC (mg/L)*2

TSS (mg/L)*2

18.6 – 22.8 

19.7 – 20.3 

7.7 – 8.1 

5.9 – 6.5 

7.2 – 35.8 

4.4 – 26.0 

110 – 290 

21.9 – 25.0 

19.5 – 20.4 

7.7 – 8.1 

12.2 – 15.1 

0.2 – 0.7 

2.0 – 3.7 

<1 – 1 

Bromate ion (mg/L)*3

THM Bromoform (mg/L)*3

 Chloroform (mg/L)*3

Bromodichlotomethane (mg/L)*3

 Dibromochloromethane (mg/L)*3

TRO (mg/L as Cl2)*4

<0.01 

<0.0001 

<0.0001 

<0.0001 

<0.0001 

<0.01 – 0.01 

0.03 – 0.04 

0.011 – 0.026 

<0.0001 

<0.0001 

0.0001 – 0.0004 

<0.01 – 0.02 

Note: *1 data number: 11, *2;data number:4, *3;data number: 4, *4;data number:11 

 *5 Untreated influent water: Sampling influent water just before treatment and *1 and *2

 analysed immediately, *3 and *4 analysed within 10 hours. 

*6 Treated discharge water: Sampling discharge ballast water just after treatment (Holding 

time in Ballast tank: 0, after DWTT passed) and *1 and *2 analysed immediately, *3 and 

*4 analysed within 10 hours. 

 * Ozone concentration at the time of ballast water injection: 4 mg/L 

 * Analytical methods: 

 Bromate ion: modified ion chromatograph-post column method 

 THM: Purge and trap-gas chromatograph method 

 TRO: DPD method 
MEPC 61/2/2 

Annex, page 12 

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

Table 2.1-1(2:) Concentration of chemical substances in pre-treatment influent water 

and in post-treatment discharged ballast water in full-scale land-based 

chronic toxicity test (seawater case) 

Items Untreated influent 

water*5 Treated discharge 

water*6

Water Temperature (°C)*1

Salinity (PSU)*1

pH*1 

Dissolved oxygen (mg/L)*1

POC (mg/L)*2

DOC (mg/L)*2

TSS (mg/L)*2

23.8 – 27.5 

32.5 – 34.0 

 8.1 – 8.2 

5.6 – 7.1 

1.0 – 10.6 

2.4 – 6.1 

24 – 40 

23.9 – 27.4 

32.4 – 33.9 

8.1 – 8.2 

9.5 – 14.6 

<0.1 – 0.2 

1.5 – 2.5 

<1 – 3 

Bromate ion (mg/L)*3

THM Bromoform (mg/L)*3

 Chloroform (mg/L)*3

Bromodichlotomethane (mg/L)*3

 Dibromochloromethane (mg/L)*3

TRO (mg/L as Cl2)*4

<0.01 

0.0001 – 0.0003 

<0.0001 

<0.0001 

<0.0001 

<0.01 – 0.02 

0.02 – 0.07 

0.017 – 0.033 

<0.0001 

<0.0001 

0.0003 – 0.0006 

0.02 – 0.08 

Brackishwater case 

Items Untreated influent 

water*5 Treated discharge 

water*6

Water Temperature (°C)*1

Salinity (PSU)*1

pH*1

Dissolved oxygen (mg/L)*1

POC (mg/L)*2

DOC (mg/L)*2

TSS (mg/L)*2

19.0 – 24.2 

19.8 – 21.1 

7.7 – 8.1 

5.9 – 6.5 

8.5 – 49.6 

4.1 – 26.0 

79 – 570 

19.1 – 25.0 

19.7 – 21.2 

7.6 – 8.1 

9.7 – 16.3 

0.2 – 1.6 

1.6 – 3.7 

<1 – 3 

Bromate ion (mg/L)*3

THM Bromoform (mg/L)*3

 Chloroform (mg/L)*3

Bromodichlotomethane (mg/L)*3

 Dibromochloromethane (mg/L)*3

TRO (mg/L as Cl2)*4

<0.01 

<0.0001 

<0.0001 

<0.0001 

<0.0001 

<0.01 – 0.03 

0.03 – 0.05 

0.010 – 0.026 

<0.0001 

<0.0001 

0.0001 – 0.0004 

<0.01 – 0.02 

Note: *1 data number:28, *2;data number:8, *3;data number: 8, *4;data number:28 

*5 Untreated influent water: Sampling influent water just before treatment, *1 and *2 

analysed immediately, *3 and *4 analysed in 10 hours. 

*6 Treated discharge water: Sampling ballast water discharge just after treatment (holding 

time in ballast tank: 0, after DWTT), *1 and *2 analysed immediately, *3 and *4 

analysed in 10 hours. 

* Ozone concentration at the time ofbBallast water injection: 4 mg/L 

 * Analytical methods: 

 Bromate ion: modified ion chromatograph-post column method 

 THM: Purge and trap-gas chromatograph method 

 TRO: DPD method 
MEPC 61/2/2 

Annex, page 13 

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

Table 2.1-1(3): Concentration of chemical substances in pre-treatment influent water 

and in post-treatment ballast water discharge during Relevant 

Chemicals removal performance test of Discharge Water Treatment 

Tank in full-scale land-based test facility (seawater case) 

Items Untreated 

influent water 

Treated to 

BWT water 

 Treated 

discharge water

Water Temperature (°C) *1

Salinity (PSU) *1

pH*1

Dissolved oxygen (mg/L) *1

 24.4 – 27.8 

31.2 – 34.0 

7.42 – 8.16 

4.89 – 6.11 

Bromate ion (mg/L) *3

Bromoform (mg/L) *3

TRO (mg/L as Cl2) immed. after sampling*1

TRO (mg/L as Cl2) after 3 hour sampling*2

<0.002 – 0.002 

<0.0001 – 0.0008 

0.01 – 0.02 

<0.02 

0.046 – 0.150 

0.10 – 0.22 

1.86 – 3.50 

2.3 – 3.0 

0.025 – 0.082 

0.0014 – 0.034 

0.02 – 0.07 

<0.02 

Note: *1 After sampling, analysed immediately. Data number: 40 

 *2 3 hours after sampling, analysed. Data number: 7 

 *3 2 days after sampling, analysed. Data number: 7 

 * Ozone concentration at the time of ballast water injection: 4 mg/L 

 * Analytical methods: 

 Bromate ion: modified ion chromatograph-post column method 

 THM: Purge and trap-gas chromatograph method 

 TRO: DPD method 

Table 2.1-1(4): TRO data from various tests of ballast water discharge measured 

by TRO monitor installed in full-scale land-based test facility 

(seawater case) 

Items Treated discharge water 

TRO (mg/L as Cl2) 0.02 – 0.16 (AV. 0.09) 

Note: Data for extension of 520 hour operation, data number; about 14000

Table 2.1-2: Information on Relevant Chemicals in SP-Hybrid BWMS Ozone 

version (including Ozone as Active Substance) 

Chemical 

Name 

Empirical 

Formula 

Molar 

mass 

Structural 

formula 

CAS 

Number 

The classification 

in accordance with 

the UN GHS 

system 

Concentration in 

discharge ballast 

water, after 

treated DWTT*1

(Bio)degradation 

rate or half-life 

AS, 

RC or 

Other 

Ozone O3 48.00 10028-15-6 

(1956) ID692 N/A*2

 5.8 Sec*3 AS 

Bromate 

ion BrO3

-

 127.9 15541-45-4 N/A 0.02 – 0.082 

mg/L Over 40day*3

 RC 

Bromoform CHBr3 252.7 75-25-2 ID165 0.0014 – 0.034 

mg/L 32 ~ 185 day*3

 RC 

TRO N/A N/A N/A N/A N/A 0.16 mg/L 

 (as Cl2) 3day *4 RC 

*.1 DWTT: Discharge Water Treatment Tank. 

*.2 Due to fast degradation rate and extremely short half-life in this system, this is completely 

separated and decomposed at the Gas /Liquid Separation Unit. Injected Ozone did not reach 

the BWT (Ballast Water Tank) and did not exist in the discharge ballast water. 

*.3 Reproduced from document MEPC 59/2/1, confidential version. 

*.4 Assumption based on actual measure of corrosion test. 

Br

C

H

Br Br
MEPC 61/2/2 

Annex, page 14 

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

2.1.4 Other Chemicals 

Hypobromous acid, Hypobromous acid ion and Bromous acid ion are theoretically generated 

in treated ballast water by this BWMS. However, as those substances change to bromoform 

or bromate ion with a reaction timescale of about one second, it can be considered that they 

are not present in the discharged ballast water due to their extremely short lifetime. 

D. Fisher et al. also pointed out that the lifetimes of these substances are extremely short 

(Fisher D. et al. 1999). It is practically impossible to measure their concentrations in the 

treated ballast water. 

Free radicals like the hydroxyl radical (OH.

) are also generated by the Ozone decomposition 

process in water. Meanwhile, the hydroxyl radical is a strong oxidizing agent, with a reaction 

rate of 106 times faster than Ozone and it is not in ballast water except for a extremely short 

time just after treatment. 

Furthermore, the generation of dibromochloromethane as a kind of trihalomethane was 

confirmed in a few tests. However, the maximum concentration in the post-treatment ballast 

water discharge was 0.0006 mg/L (0.6 μg/L), which is extremely low. As NOEC of 

dibromochloromethane is 0.063 mg/L (Ecological Effect Test, Ministry of the Environment, 

Japan 1995), Predicted No Effect Concentration (NOEC) is 0.63 μg/L in case of using the 

assessment factor of 100 and the discharge concentrations observed in various tests is 

equivalent to this PNEC even if dilution after the discharge is not taken into consideration. 

As described above, hypobromous acid, hypobromous acid ion, bromous acid ion, free 

radicals and dibromochloromethane were generated by the ballast water treatment using this 

BWMS but they are not included in the analysis of the discharge ballast water. We judged 

that they are not pertinent as Relevant Chemicals because they are believed not to have the 

potential to affect the marine environment of the discharge. 

2.2 Data on effects on aquatic plants, invertebrates and fish, and other biota, 

including sensitive and representative organisms (G9:4.2.1.1) 

2.2.1 Acute aquatic toxicity 

No further information in addition to that of Active Substance and Relevant Chemicals in the 

previous application (MEPC 59/2/1) was found. 

Concerning treated ballast water (G9: 5.2.3), the acute toxicity test for ballast water treated 

by the SP-Hybrid BWMS Ozone version was applied to the following test water under 

Guidelines (G8) influent test water conditions for seawater and brackish water by using 

full-scale system adopted for Guidelines (G8) land-based test. Ozone was injected in a 

suitable manner to achieve an Ozone concentration of 4 mg/L in the influent ballast 

water (200m3/h). 

Test water: Discharged ballast water after Relevant Chemicals were removed in the 

Discharge Water Treatment Tank immediately following treatment of Ozone injection 

(Holding time; 0 hours) 

No acute toxicity for three kinds of organisms in any undiluted discharge ballast (seawater or 

brackish water) was observed. The maximum concentration of Relevant Chemicals in 

exposure water was 0.07 mg/L for bromate ion, 0.029 mg/L for bromoform and 0.02 mg/L 

(as Cl2) for TRO. 
MEPC 61/2/2 

Annex, page 15 

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

Concentration of both bromate ion and bromoform declined substantially from the acute 

toxicity value of the previous ECOTOX database. Also, the result for TRO showed less 

than 0.02 mg/L of concentration, which was identical to the value for no acute toxicity. 

2.2.2 Chronic aquatic toxicity 

No additional information in addition to that of Active Substance and Relevant Chemicals in 

the previous application (MEPC 59/2/1) was found. 

Concerning treated ballast water (G9: 5.2.3), the chronic toxicity test for ballast water treated 

by the SP-Hybrid BWMS Ozone version was applied to the following test water under 

Guidelines (G8) influent test water conditions for seawater and brackish water by using 

full-scale system adopted for Guidelines (G8) land-based test. Ozone was injected in a 

suitable manner to achieve an Ozone concentration of 4 mg/L in the influent ballast 

water (200 m3/h). 

Test water: Discharged ballast water after Relevant Chemicals were removed in the 

Discharge Water Treatment Tank immediately following treatment of Ozone injection 

(Holding time; 0 hours) 

No chronic toxicity of three kinds of organism in the undiluted ballast water discharge, 

including seawater and brackish water was observed. The maximum concentration of 

relevant chemicals in exposure water was 0.07 mg/L for bromate ion, 0.33 mg/L for 

bromoform and 0.02 mg/L (as Cl2) for TRO. 

Above all, concentration of bromate ion and bromoform substantially declined from the 

chronic toxicity value of the previous ECOTOX. 

2.2.3 Endocrine disruption 

There are no endocrine disruption data for Ozone, bromate ion, bromoform or TRO (as O3). 

The reason is that when considering the structure of these compounds, it is not expected that 

endocrine disruption would occur. 

2.2.4 Sediment toxicity 

Ozone is an inorganic chemical with a short half-life in the aquatic environment 

i.e. 5.3 to 5.8 seconds in seawater and a few minutes to half-hour in fresh water depending 

on water condition. 

Bromate ions are water-soluble and dissolved as ions. 

The logPow for bromoform is 2.4, which is smaller than logPow: 3. 

According to the results of corrosion test the half-life of TRO generated by SP-Hybrid BWMS 

Ozone version is as short as three days. 

Therefore, Ozone and Relevant Chemicals are not expected that TRO would show sediment 

toxicity. 
MEPC 61/2/2 

Annex, page 16 

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

2.2.5 Bioavailability/biomagnification/bioconcentration 

Ozone is an inorganic compound. Its half-life is as short as 5.3 to 5.8 seconds in seawater 

and a few minutes to a half-hour in fresh water though it depends on the water condition. 

The logPow for bromate ion is as very low as -7.18. (SRC Database) 

There is a data item on biomagnification/bioconcentration of bromoform in Cyprinus carpio, a 

fresh water fish. The bioconcentration factor (BCF) values of 7.1 to 21 and 7.7 to 19 were 

obtained after a 6-week exposure to bromoform at concentrations of 0.1 and 0.01 mg/L, 

respectively (NITE, 2007), indicating that the bromoform is not subject to significant 

biomagnification/bioconcentration. In consistency with this, the logPow of bromoform (2.4) is 

also quite low. 

According to the results of corrosion test the half-life of TRO generated by SP-Hybrid 

BWMS Ozone version was as short as three days. Therefore, no significant 

biomagnification/bioconcentration of Ozone and Relevant Chemicals is expected. 

2.2.6 Food web/population effects 

Ozone is an inorganic chemical with a short half-life in the aquatic environment 

i.e. 5.3 to 5.8 seconds in seawater and a few minutes to a half-hour in fresh water. Therefore, 

the possibility of an effect on the food web/population is low because no biomagnification of 

Ozone is expected in all organisms, algae, invertebrates, and fish food webs. 

Bioaccumulation of bromate ions is extremely low as logPow is -7.18. Therefore, the 

possibility of affecting the food web/population is low because the biomagnification of 

bromate ion is expected to be low in all organisms, algae, invertebrates, and fish food webs. 

The BCF of bromoform is under 21. Therefore, the possibility of affecting the food 

web/population is low because the biomagnification of bromoform is expected to be low in all 

organisms, algae, invertebrates, and fish food webs. 

There is no biomagnification/bioconcentration of TRO because the half-life of TRO generated 

by SP-Hybrid BWMS Ozone version was as short as 3 days according to the results of the 

corrosion tests. Therefore, the possibility of affecting the food web/population is low. 

2.3 Data on mammalian toxicity (G9: 4.2.1.2) 

Concerning with mammalian toxicity, Ozone as an Active Substance and bromate ion, 

bromoform and TRO as Relevant Chemicals in SP-Hybrid BWMS are summarized below.

2.3.1 Active Substance 

Ozone shows a strong toxicity with exposure of the inhalation pathway. Therefore, it is 

necessary to take strong measures to prevent Ozone exposure to the human inhalation 

pathway. Moreover, Ozone has a possibility of mutagenicity in humans. 

However, Ozone is classified as A4 (i.e. not classified as a human carcinogen) by the 

American Conference of Governmental Industrial Hygienists (ACGIH) (ACGIH, 2001b). 

Because Ozone is not included in ballast tank or discharge ballast water in this BWMS and 

has short half-life, there is no risk exposure in these inhalation pathways. 
MEPC 61/2/2 

Annex, page 17 

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

2.3.2 Relevant Chemicals 

2.3.2.1 Bromate ion 

There are some research results on potassium bromate and on Sodium bromate. 

Many researchers point out that Potassium bromate and Sodium bromate may cause effects 

on the skin or the eyes resulting from exposure by gavage. 

Lethal doses of Potassium bromate are considered to be 200 mg/kg to 500 mg/kg of 

body-weight. Bromate is absorbed into the gastrointestinal tract by oral administration to both 

humans and animals. Toxic symptoms of bromate include nausea, vomiting, abdominal pain, 

anuria, diarrhoea, various degrees of central nervous system depression, hemolytic anemia 

and pulmonary edema. However, most of these effects are reversible. Sodium bromate is 

reported to cause redness in the skin and redness and pain in the eyes. 

Although there is no information on carcinogenicity of bromates to humans, it is possible that 

bromates are carcinogenic to humans because carcinogenicity tests using experimental 

animals show that there is an apparent dose dependency in the relationship between 

bromates and the incidence rate and degree of severity of tumors (WHO, 2005). 

The International Agency for Research on Cancer (IARC) classifies Potassium bromate as 

Group 2B (the agent is possibly carcinogenic to humans). 

From the above, human exposure to bromate ions needs to be avoided completely. 

When shipboard personnel enter the tank, they need to wear complete protective equipment 

because bromate ions may still be present. Although bromate ions may be present in the 

discharge ballast water under the worst scenario, which is the maximum discharge 

concentration of 0.082 mg/L, there should be no effect on the general public due to natural 

dilution after discharge. 

2.3.2.2 Bromoform 

Based on experimentation with laboratory animals, the acute toxicity oral LD50 values for 

bromoform are reported to be 1,400 mg/kg to 1,550 mg/kg bw in mice and 1,147 to 1,388 mg/kg 

bw in rats. Irritation of the skin and eyes, headache, dizziness, memory loss, loss of 

consciousness, convulsion, pneumonedema were reported. Central nervous system 

depression and effects to the kidneys and liver were also reported. 

In humans, central nervous system depression with coma and loss of reflexes was observed 

following accidental ingestion of liquid bromoform (ACGIH, 2001a). 

The ICSC database mentions irritation for human eyes with a flare reaction which may be 

painful. 

The affected organs resulting from repeated doses of bromoform were the liver and kidney. 

With the effect of 13 weeks oral administration (mixed feeding stuff) to F344 rats (vacuolation 

of hepatic cells) regarded as an indicator, 50 mg/kg/day is judged to be the Lowest Observed 

Adverse Effect Level (LOAEL) of oral administration. 

No toxicity in mice was found to develop at a maximum concentration of 200 mg/kg/day. 

Regarding reproductive toxicity, it was reported that 50 mg/kg bw/day did not cause 

embryonic skeletal mutation or interparietal deviations in rats. 
MEPC 61/2/2 

Annex, page 18 

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

Regarding carcinogenicity, there was no increase in the incidence of lung tumors in mice by 

administration. A significant increase in the incidence of adenomatous polyp and 

adenocarcinomas (combined) of the large intestine was observed in rats of both sexes with 

administration of over 200 mg/kg/day. 

The International Agency for Research on Cancer (IARC) concluded that there were 

inadequate human data and limited animal data and assigned bromoform to the weight of 

evidence group 3, which is not classifiable as to carcinogenicity in humans 

(IARC 1991a, 1999a). 

Regarding genotoxicity, in vitro tests using CHL cells and CHO cells, conflicting results were 

obtained from a DNA damage test and a chromosomal aberration test. 

There were positive results in DNA damage tests using micro-organisms, in a mutagenicity 

study, in a chromosomal aberration test using Aspergillus nidulans, and a mutagenicity study 

using mouse lymphoma cells. 

Furthermore, in vivo, an SCE test using mice and micronucleus assay showed positive. 

From these results, it seems that bromoform is genotoxic. 

In general, trihalomethanes including bromoform are rapidly absorbed after oral 

administration, primarily metabolized to carbon dioxide, and rapidly excreted. 

Although bromoform appears to have a significant propensity for the metabolism, numerous

in vivo toxicity studies indicate that it is not very potent as a toxicant and or as a carcinogen. 

Regarding the mammalian toxicity of bromoform above, the risk is not high because the 

maximum concentration of bromoform generated by this BWMS is as low as 0.22 mg/L. 

However, as is the case for bromate ions, when shipboard personnel enter in the tank, they 

need to wear complete protective equipment because bromoform may exist in the ballast 

tank. 

Although bromoform has the potential to exist in ballast water discharge, in the worst 

scenario, which is the maximum discharge concentration of 0.034 mg/L discharged, there 

would be no effect on the general public due to dilution after the discharge. 

2.3.2.3 Total Residual Oxidants (TRO) 

TRO represents the total quantity of oxidants and is not a specific chemical substance, 

therefore data were not available. 

When shipboard personnel enter the tank, they need to wear complete protective equipment 

because TRO may remain there. 

Although TRO has a potential to exist in the ballast water discharge, in the worst scenario, 

which is the maximum discharge concentration 0.16 mg/L, there would be no effect on the 

general public due to dilution after the discharge. 
MEPC 61/2/2 

Annex, page 19 

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

2.4 Data on environmental fate and effect under aerobic and anaerobic conditions 

(G9: 4.2.1.3) 

2.4.1 Modes of degradation (biotic; abiotic) 

2.4.1.1 Active Substance 

Ozone self-decomposes into oxygen under aerobic or anaerobic conditions. 

Ozone self-decomposes rapidly in water because it is an unstable substance in water. 

Under anaerobic conditions, dissolved oxygen (DO) may increase due to oxygen generated 

by Ozone decomposition. Ozone is not capable of being hydrolyzed. 

2.4.1.2 Relevant Chemicals 

2.4.1.2.1 Bromate ion 

Bromate is decomposed by micro-organism exiting methane bacterium, denitrification 

bacterium, sulfate reducing bacteria under anaerobic condition (Hijnen et al., 1994). Bromate 

is decomposed physicochemically by reaction with ferrous ions (Siddiqui et al., 1995) or 

activated carbon (Siddiqui et al., 1996) if these substances are present. Bromate ions are 

reduced to bromide ion under the environmental condition of high energy electromagnetic 

irradiation (Siddiqui et al., 1996). Bromate ions are not hydrolyzed. 

2.4.1.2.2 Bromoform 

In an aerobic biodegradation test with improved culture flasks for volatile substances based 

on "Law Concerning the Examination and Regulation of Manufacture, etc. of Chemical 

Substances", bromoform was considered to be persistent because its decomposition rate by 

biochemical oxygen consumption (BOD) measurement was 0% under conditions of 

concentration of test article of 100 mg/L, activated sludge of 30 mg/L, and test period of 

four weeks. 

Bromoform decomposition rate was also 0% in gas chromatograph (GC) measurement 

(MITI: the Ministry of Economy, Trade and Industry, Japan, 1986). 

On the other hand, one report showed that biodegradation was confirmed under condition of 

low test article concentration and long naturalization. 

In a test where yeast extract was added to a culture solution at a test temperature of 25°C 

and test article concentration of 5 mg/L and 10 mg/L, the decomposition rate measurement 

by total organic carbon (TOC) was 11% and 4% for 7 days. 

In a test where subculture was conducted every 7 days under the test article concentration 

of 5 mg/L, decomposition rate involved in subculture was increased by phased-naturalization 

as follows: primary culture: 22%; secondary culture: 40%; tertiary culture: 48% 

(Tabak et al., 1981). 

These results suggest that the biodegradability of bromoform is strongly affected by its 

concentration and naturalization of the micro-organism, since biodegradation of bromoform is 

high when its concentration is low and the start of the decomposition is relatively late under 

aerobic conditions. 
MEPC 61/2/2 

Annex, page 20 

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

A report shows that a low concentration of bromoform (less than 100 μg/L) was biodegraded 

under anaerobic conditions. 

More than 99% of bromoform in an average initial concentration of 34 μg/L was decomposed 

in a column filled with carriers of methane bacterium in the presence of acetate 

(retention time: 2 days, 22 to 23°C) (Bouwer and McCarty, 1983a). 

In a test where nitrite and nitrate were reduced to nitrogen and nitrogen monoxide by the 

action of denitrifying bacteria under anaerobic conditions (denitrifying condition), an initial 

bromoform concentration of 66 μg/L decreased to 59 μg/L, 37 μg/L, 35 μg/L and 2 μg/L 

after 2, 3, 4 and 6 weeks (Bouwer and McCarty, 1983b). 

In conclusion, it is assumed that bromoform is not easily biodegraded under aerobic 

conditions. However, it is assumed that bromoform is biodegraded under low concentration 

conditions, naturalization for long period and others. It is also assumed that bromoform is 

biodegraded if its concentration is low, even under anaerobic conditions. 

Since no chemical bond of bromoform is easily hydrolyzed, bromoform is not hydrolyzed in 

water. 

2.4.1.2.3 Total Residual Oxidants (TRO) 

TRO represents the total quantity of oxidants and is not a specific chemical substance and it 

is therefore hard to discuss its degradability. TRO generated by the reaction of seawater with 

Ozone seems to change finally to bromate ion and bromoform as Relevant Chemicals in this 

application. 

The half-life of TRO generated by this BWMS was determined to be 3 days according to the 

result of the corrosion tests. 

2.4.2 Bioaccumulation, partition coefficient, octanol/water partition coefficient 

2.4.2.1 Active Substance 

No data are available on the bioaccumulation of Ozone. 

Ozone is an inorganic compound and its half-life is as short as 5.3 to 5.8 seconds in 

seawater and several minutes to tens of minutes in fresh water depending on water 

condition. Therefore, bioaccumulation is not applicable to Ozone. 

2.4.2.2 Relevant Chemicals 

2.4.2.2.1 Bromate ion 

No information on bioaccumulation of bromate is available. However, it is assumed that 

bromate does not bioaccumulate since its logPow is extremely low at -7.18. 

2.4.2.2.2 Bromoform 

Data on the bioaccumulation potential of bromoform using carp, which is fresh water fish, are 

available (NITE, 2007). In a test where carp were exposed to bromoform of 0.1 

and 0.01 mg/L for 6 weeks, the BCF was 7.1 to 21 and 7.7 to 19. Therefore, it is assumed 

that bromoform has no bioaccumulation. This result is consistent with the low logPow of 

bromoform, which is 2.4. 
MEPC 61/2/2 

Annex, page 21 

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

2.4.2.2.3 Total Residual Oxidants (TRO) 

TRO represent the total quantity of oxidants and is not a specific chemical substance, 

therefore data were not available. However, the half-life of TRO generated by this BWMS 

was determined to be three days according to the results of the corrosion test. It is 

considered that there is no bioaccumulation in view of the decomposition rate. 

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

(ballast water, marine and fresh water) 

No further information in addition to that in the previous application (MEPC 59/2/1) was 

found. 

2.4.3.1 Active Substance 

As the half-life of Ozone is as short as 5.3 to 5.8 seconds in seawater and several to several 

tens minutes in fresh water and Ozone is decomposed in a short period, no Ozone exists in 

the ballast water discharge. Furthermore, this system adopts a Gas/Liquid Separation Tank 

to separate the Ozone, which does not dissolve in ballast water so that it does not remain in 

the ballast tank. The Relevant Chemicals described below are generated if bromide ions 

exist in seawater or intake ballast water but they are not generated in fresh water where 

bromide ions are not present.

2.4.3.2 Relevant Chemicals 

2.4.3.2.1 Bromate ion 

The half-life of bromate ion generated by this BWMS treatment using seawater and brackish 

water is >40 days and therefore bromate ions have high persistence. Bromate ions are not 

generated in fresh water where bromide ion does not exist. 

2.4.3.2.2 Bromoform 

The half-life of bromoform generated by SP-Hybrid BWMS Ozone version treatment using 

seawater and brackish water is 32 to 185 days and therefore bromoform has high 

persistence. Bromoform is not generated in fresh water where bromide ion does not exist. 

As bromoform is highly volatile, it has a nature to disappear promptly from the water. 

2.4.3.2.3 Total Residual Oxidants (TRO) 

If seawater is treated by this BWMS, the half-life of TRO generated by this BWMS was 

determined to be three days according to the results of the corrosion test and persistence is 

low. In the case of brackish water, the half-life is shorter at 0.75 days as Bromide ion 

concentration present in brackish water is at a low level. This implies that there would be 

lower persistence in fresh water. 

2.4.4 Reaction with organic matter 

The formation of halogenated hydrocarbon by reaction with organic matter was examined in 

the test water generated in the chronic toxicity test which was conducted for the previous 

application (MEPC 59/2/1). According to this result, the generation of halogenated 

hydrocarbon was not confirmed at this BWMS. The reaction of the Active Substance and 

Relevant Chemicals with organic matter is shown below. 
MEPC 61/2/2 

Annex, page 22 

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

2.4.4.1 Active Substance 

When Ozone is injected to seawater, Ozone reacts with organic matter and inorganic matter. 

Ozone reacts with organic matter in preference to the inorganic bromide ion and so Ozone is 

consumed. Consequently, the amount of Relevant Chemicals generated by the reaction 

between Ozone and bromide ion is reduced. 

2.4.4.2 Relevant Chemicals 

2.4.4.2.1 Bromate ion 

Bromate ions are oxidants which ultimately revert to bromide ions through the reaction with 

organic matter (WHO, 1996) and through biodegradation (Hijnen et al, 1994). 

2.4.4.2.2 Bromoform 

Bromoform is a THM and hypobromous acid, which is a precursor and intermediate product 

of a THM, generated by reaction with organic matter. 

Bromoform does not react with organic matter due to its stable structure. 

2.4.4.2.3 Total Residual Oxidants (TRO) 

As TRO represents the total mass of oxides, it is not possible to identify a specific reaction 

with organic matter. Generally, oxides such as the bromate ion, hypobromous acid ion and 

bromous acid ion react with organic matter and increase the rate of its degradation. 

2.4.5 Potential physical effects on wildlife and benthic habitats 

2.4.5.1 Active Substance 

As Ozone disappears with self-decomposition and by transformation to Relevant Chemicals 

immediately after injection to water, it has less potential to be discharged. Therefore, it has 

little potential for physical effects on wildlife and benthic habitats. 

2.4.5.2 Relevant Chemicals 

2.4.5.2.1 Bromate ion 

Bromate ions have high solubility (70 g/L at 20°C) and normally dissolve in water as ions. 

Even though ballast water after treatment may contain bromate ions, its maximum discharge 

concentration is low at 0.082 mg/L. 

If discharged, they revert to Bromide ions by reaction with organic matter. Therefore, they 

have little potential for physical effects on wildlife and benthic habitats. 

2.4.5.2.2 Bromoform

As dissolution rate of bromoform to water is 0.1 g/100 ml, it potentially dissolves in water at 

its maximum discharge concentration of 0.22 mg/L. Therefore, there are few potential 

physical effects. Meanwhile, due to its high volatility bromoform dissipates in air. As its 

emission concentration is lower than the background concentration in the air, few potential 

physical effects exist. 
MEPC 61/2/2 

Annex, page 23 

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

2.4.5.2.3 Total Residual Oxidants (TRO)

TRO represents the total quantity of oxidants and is not a specific chemical substance, 

therefore, data were not available. However, it can be considered that there are few potential 

physical effects on wildlife and benthic habitats due to a great magnitude of dissolution to 

water and short half-life of three days. 

2.4.5.3 Treated ballast water 

SP-Hybrid BWMS Ozone version may generate Relevant Chemicals as described above, 

however, they are chemical substances that have no potential physical effects on wildlife and 

benthic habitats. 

If Relevant Chemicals remain in ballast water discharge, Relevant Chemicals can be 

removed by Discharge Water Treatment Tank. 

Therefore, it can be considered there are no potential physical effects on wildlife and benthic 

habitats in discharge ballast water treated by this BWMS. 

2.4.6 Potential residues in seafood 

2.4.6.1 Active Substance 

The half-life of Ozone is as short as 5.3 to 5.8 seconds in seawater and several minutes to 

tens of minutes in fresh water so it decomposes in a short time. 

As described in paragraph 2.4.5.1, it can be considered that there are no potential physical 

effects on wildlife and benthic habitats. Therefore, it can be also considered that there are no 

bioaccumulations in seafood in view of the decomposition of Ozone in the water and the 

solubility to the water. 

2.4.6.2 Relevant Chemicals 

2.4.6.2.1 Bromate ion 

Bromate ion can be considered to have no potential physical effects on wildlife and benthic 

habitats. Therefore, it can be also considered that there are no potential residues in seafood. 

2.4.6.2.2 Bromoform

Bromoform can be considered to have no potential physical effects on wildlife and benthic 

habitats. Therefore, it can be also considered that there are no potential residues in seafood. 

2.4.6.2.3 Total Residual Oxidants (TRO)

TRO can be considered to have no potential physical effects on wildlife and benthic habitats. 

Therefore, it can be also considered that there are no potential residues in seafood. 
MEPC 61/2/2 

Annex, page 24 

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

2.4.7 Any known interactive effects 

2.4.7.1 Active Substance 

Oxygen is generated by Ozone self-decomposition in water. For this reason, the 

concentration of dissolved oxygen is raised. 

2.4.7.2 Relevant Chemicals 

2.4.7.2.1 Bromate ion 

Bromate ions are rarely reduced in general environmental water. 

However, bromate ions are reduced to bromide ions in the presence of ferrous ions or 

activated carbon. 

2.4.7.2.2 Bromoform 

Bromoform is a relatively stable substance and is persistent under aerobic conditions but it is 

biodegraded by methane bacteria or denitrifying bacteria under anaerobic conditions. 

2.4.7.2.3 Total Residual Oxidants (TRO) 

TRO represents the total quantity of oxidants generated by the reaction of Ozone with 

bromide ions, which are then finally converted to bromoform and bromate ions. 

2.5 Physical and chemical properties for the Active Substances and preparations 

and treated ballast water, if applicable (G9: 4.2.1.4) 

Concerning corrosivity to the materials or equipment of normal ship construction, the results 

of the corrosion test using the full-scale land-based test facility showed corrosion effects 

within the allowable range. 

Concerning other items, no further information in addition to that in the previous application 

(MEPC 59/2/1) was found. 

2.6 Analytical methods at environmentally relevant concentration (G9: 4.2.1.5) 

Table 2.6-1 showed measurement method of Ozone as an Active Substance and analytical 

methods of the Relevant Chemicals. 
MEPC 61/2/2 

Annex, page 25 

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

Table 2.6-1: Analytical methods at environmentally relevant concentration of the 

Active Substance and the Relevant Chemicals 

Substance Method Applicability Sensitivity 

Reference/Comments/ 

Justification for missing 

data 

Ozone 

・ UV method 

・ KI method 

(as Oxidants) 

in gas 

in liquid 

0.01 mg/L±1%FS 

(UV absorbance) 

0.15 mg/L (KI method) 

IOA Standardization 

Committee 

Bromate 

ion IC+PC method in liquid 0.01 mg/L ISO 15061:2001 

Bromoform 

PT-GC/MS 

Method or HSGC/MS method 

in liquid 0.0002 mg/L or 

0.0001 mg/L 

tap water test method in 

Japan* 

TRO 

DPD Absorption 

Photometry 

Method

in liquid 0.01 mg/L, 0.02 mg/L 

or 0.035 mg/L 

In accordance with tap 

water test method * VI-2 

17.3 (Japan Water Works 

Association 2001) 

*Water analytical manual published by Japan Water Works Association 

3 USE OF THE ACTIVE SUBSTANCE 

3.1 Summary of SP-Hybrid BWMS Ozone version 

The SP-Hybrid BWMS Ozone version is designed to give sufficient consideration to 

downsizing, modularization, safety and reliability of component units. This BWMS adopts the 

shipbuilding and environmental technologies developed over several years. It is designed to 

be easily adapted to any ballast line of new or existing ships. 

3.1.1 Components and outline 

Figure 3.1-1 showed the configuration of the SP-Hybrid BWMS Ozone version. 

Figure 3.1-1: Configuration of SP-Hybrid BWMS Ozone version 
MEPC 61/2/2 

Annex, page 26 

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

3.1.2 Characteristics 

The SP-Hybrid BWMS Ozone version has characteristics as follows: 

.1 It efficiently utilizes the physical organism deactivation action of the Special 

Pipe and the organism inactivation action of Ozone and Relevant 

Chemicals, which are generated by the reaction between Ozone and 

bromide ions in seawater or other water. 

.2 Since Ozone, which is an Active Substance, is produced by the Ozone 

Generator Module installed on board, there is no need for installation and 

storage on board of either the Active Substance or Preparations. 

.3 The inactivation treatment of aquatic organisms in the ballast water is 

applied only once when it is loaded on board. 

.4 Many of Relevant Chemicals generated by injecting Ozone into the 

seawater (or brackish water) are degraded in the ballast tanks. However, if 

the holding time is short, Relevant Chemicals remain in the ballast water. 

The Discharge Water Treatment Tank (DWTT) is installed for the purpose 

of removing such remaining Relevant Chemicals. 

 If the TRO concentration prior to the DWTT exceeds 0.2 mg/L (as Cl2), 

defined as the maximum allowable discharge concentration, the ballast 

water is discharged through the DWTT. If the TRO concentration is lower 

than 0.2 mg/L (as Cl2), the ballast water is discharged without going 

through the DWTT. 

 If the TRO concentration exceeds 0.15 mg/L (as Cl2) after the DWTT, an 

alarm is raised. Furthermore, if the TRO concentration exceeds 0.2 mg/L 

(as Cl2), defined as the maximum allowable discharge concentration, the 

discharge automatically stops. Safe discharge of the ballast water to the 

environment is secured by these measures. 

 The installation of this DWTT and surveillance of oxidant removal 

performance with the TRO monitor are the most important distinguishing 

features of this BWMS regarding environmental conservation and the 

prevention of inter-oceanic movement of aquatic organisms. 

.5 Each major component and its valves are automatically operated or 

remotely controlled (remote operation) from the Ballast Water Treatment 

Control Panel. The operating condition can be monitored on the display 

screen of this control panel. No manual operation of equipment or valves 

by the officers or crew is required except for maintenance or emergency 

operation, in the case of a serious failure. 

.6 All possible safety measures have been made for Ozone leakage and 

waste Ozone treatment. 

.7 All possible measures have been taken against corrosion for areas affected 

by Ozone. 
MEPC 61/2/2 

Annex, page 27 

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

3.2 Manner of application (G9: 4.2.6 and 7) 

3.2.1 Maximum dosage concentration of Ozone 

In the actual usage of this BWMS, Ozone is injected so that its concentration in the 

loading ballast water is 3 mg/L. The Ozone injection rate is automatically controlled to 

achieve 3 mg/L in the loading ballast water even if the ballast water flow rate fluctuates. 

On the other hand, in the application for approval of this BWMS under Procedure (G9), 

the Ozone injection rate for the loading ballast water was set to achieve a concentration 

of 4 mg/L. The reason for the higher concentration is to evaluate the effects on the hull, 

human and environment at a more severe condition than the actual Ozone concentration 

of 3 mg/L. This creates a safety margin in the operation of the actual system. The Ozone 

injection rate to the loading ballast water used for various tests for Procedure (G9) 

application was also controlled to achieve 4 mg/L. 

3.2.2 Holding time 

The holding time in the ballast tank after the treatment with the SP-Hybrid BWMS Ozone 

version is not specified. The performance of the Discharge Water Treatment Tank to remove 

Relevant Chemicals ensures that the concentration of Relevant Chemicals in the ballast 

water discharge does not exceed the maximum allowable discharge concentration of the 

Relevant Chemicals even if the discharge occurs immediately after the inactivation 

treatment. 

3.2.3 The maximum allowable discharge concentration of the Relevant Chemicals 

The maximum allowable discharge concentration of Relevant Chemicals of the SP-Hybrid 

BWMS Ozone version is 0.082 mg/L for bromate ion, 0.22 mg/L for bromoform and 0.2 mg/L 

(as Cl2) for TRO. 

According to the results of various tests implemented for reapplication of Final Approval, the 

maximum discharge concentration of Relevant Chemicals was 0.082 mg/L for 

bromate ion, 0.034 mg/L for bromoform and 0.16 mg/L (as Cl2) for TRO. 0.082 mg/L is taken 

as the maximum allowable discharge concentration of bromate ion. Removal performance of 

bromoform showed a tendency to decrease after a long period of operation of the DWTT. 

From the standpoint of risk evaluation and safety, the maximum allowable discharge 

concentration of bromoform was defined as 0.22 mg/L, which was the maximum 

concentration before post treatment of DWTT. The majority of TRO concentration 

measurements in the ballast water discharge even in case of post treatment by DWTT 

immediately after ozone injection (which is unlikely to occur in a real operation) showed less 

than 0.1 mg/L (as Cl2) and the maximum was 0.16mg/L. This resulted in establishment 

of 0.2 mg/L (as Cl2) as the maximum allowable discharge concentration. 

3.2.4 Handling, use, storage and transport of the chemicals 

Since Ozone, which is an Active Substance, is generated by the Ozone Generator 

Module on board, its delivery to the ship, loading and storage of such Active Substance 

or Preparations on board are not required. 
MEPC 61/2/2 

Annex, page 28 

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

3.2.5 Procedures and use of the system 

3.2.5.1 Ballasting operation 

The system is operated by the following procedures when the ballast water is loaded: 

.1 ballasting is carried out using the Ballast Water Treatment Control Panel; 

.2 ballasting cannot start if the Ozone Generator Module has not been 

prepared; 

.3 Ozone is injected into the ballast water at a rate which is controlled to 

achieve a constant Ozone concentration of 3 mg/L in the loading ballast 

water. The Ozone flow rate corresponds to the ballast water flow rate 

measured with a flow meter. The Ozone concentration in the loading 

ballast water is set and fixed at the time of shipment from the factory and 

the operator cannot change it. The Ozone supply capacity is sufficient to 

prevent the concentration from decreasing below 3 mg/L based on the 

assumed maximum flow rate of the ballast water; and 

.4 If any significant problem arises in the Ozone Generator, the ballast pump, 

other components, the measurements of pressure, or the flow rate or other 

conditions, an alert is issued and the system automatically makes an 

emergency stop. The appropriate valves are automatically controlled to be 

in the safe position in an emergency stop. 

3.2.5.2 De-ballasting operation 

When the ballast water is discharged, the system is operated by the following procedure: 

.1 de-ballasting is operated using the Ballast Water Treatment Control Panel; 

.2 when de-ballasting starts, the valves are automatically opened or closed as 

appropriate and a de-ballasting line passing through Discharge Water 

Treatment Tank is automatically established. The officers and crew cannot 

change the line by arbitrary actions. If the line is changed or cannot be 

established, an interlock prevents the de-ballasting operation from being 

started, except in the case of operation for maintenance or in emergencies 

such as serious failures; 

.3 if the TRO concentration measured prior to the DWTT exceeds the 

maximum allowable discharge concentration of 0.2 mg/L (as Cl2), the 

ballast water is discharged after post treatment by the DWTT. Otherwise it 

is discharged using the bypass; 

.4 the de-ballast water flow rate can be monitored on the display screen of the 

Ballast Water Treatment Control Panel. If the flow rate is excessively high, 

an opening adjusting valve is automatically controlled to secure the 

performance of Discharge Water Treatment Tank; 

.5 a pressure gauge is installed before and after the Discharge Water 

Treatment Tank to monitor the clogging of the system and arbitrary removal 

of the activated carbon filled in the Discharge Water Treatment Tank by the 

officers or crew. Each pressure value is indicated on the Ballast Water 

Treatment Control Panel and is automatically recorded; 
MEPC 61/2/2 

Annex, page 29 

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

.6 the Clogging of Discharge Water Treatment Tank is prevented by 

backwashing; and 

.7 the TRO concentration even after post treatment by the DWTT is constantly 

surveyed. If the measured TRO concentration exceeds 0.15 mg/L (as Cl2), 

an alert is raised for the operator to check the amount of activated carbon. 

Should the TRO concentration exceed the maximum allowable discharge 

concentration of 0.2 mg/L (as Cl2), the discharge is automatically stopped. 

The monitored TRO concentration is automatically recorded on the Ballast 

Water Treatment Control Panel. 

3.2.6 Risk management measures in case of emergency 

Generally speaking, the major risks with ships are fire and flood. Regarding fire, safety is 

enhanced by implementing the following measures to minimize the risk: 

.1 in case a fire occurs in the engine room or in the room where the Ozone 

Generator is installed, there is a facility to perform an emergency stop from 

outside the engine room or the room housing the Ozone Generator; and 

.2 in the case of a fire, the alarm system gives priority to stopping the electric 

supply to the Ozone Generator. This halts production of Ozone, which 

would otherwise help the fire. 

4 MATERIAL SAFETY DATA SHEETS (G9: 4.2.7) 

The MSDS of Ozone, an Active Substance of the SP-Hybrid BWMS Ozone version, the 

MSDS of bromate ions, potassium bromate and bromoform, which are Relevant Chemicals, 

and the MSDS of activated carbon (brand name; SHIRASAGI WH2c8/32L, which is superior 

in the oxidant removal performance of the Discharge Water Treatment Tank (DWTT)) are 

shown in appendix 7 in the confidential version. 

5 RISK CHARACTERIZATION 

5.1 Screening for persistence, bioaccumulation and toxicity (G9: 5.1) 

5.1.1 Persistence (G9: 5.1.1.1) 

The half-life of Ozone and the TRO in the water is very short as described in section 2.4.1 of 

this annex. On the other hand, the half-life of bromate ion and bromoform is respectively 

more than 40 days and 32 days-185 days so these substances were confirmed to be 

persistent. 

5.1.2 Bioaccumulation (G9: 5.1.1.2) 

As Ozone is an inorganic compound and its half-life in the water is short, it is considered that 

there is no potential for bioaccumulation. 

It is also considered that there is no bioaccumulation potential for bromate ion, bromoform or 

TRO as described in section 2.2.5 of this document. 
MEPC 61/2/2 

Annex, page 30 

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

5.1.3 Toxicity test (G9: 5.1.2.3) 

The toxicity of a chemical is judged using the chronic toxicity value of 0.01 mg/L. 

The chronic toxicity NOEC of Ozone is 0.002 mg/L and therefore Ozone is classed as a toxic 

substance. The chronic toxicity NOEC of bromate ion is 0.125 mg/L and the chronic toxicity 

NOEC (MATC) of bromoform is 4.8 mg/L and so these are not classed as toxic substances. 

No toxic effect was observed according to the result of repeated chronic toxicity tests for the 

test water containing the TRO of 0.02 mg/L (as Cl2) and so the TRO in the ballast water 

discharge of this BWMS is classified as no toxic. 

5.1.4 Do the Ozone and Relevant Chemicals meet all three criteria for PBT? 

The PBT criteria of Active Substance and Relevant Chemicals used in the SP-Hybrid BWMS 

Ozone version as described above are summarized in Table 5.1-1. Active Substance and 

Relevant Chemicals of this BWMS are not identified as PBT substances. 

Table 5.1-1: PBT criteria of Active Substance and Relevant Chemicals 

 Persistent (y/n) Bioacumulative 

(y/n) Toxic (y/n)

Reference/Comments/ 

Justification for 

missing data

PBT criteria 

Half-life: 

> 60 days in 

marine water, or 

> 40 days in 

freshwater,* or 

> 180 days in 

marine 

sediments, or 

> 120 days in 

freshwater 

sediments

Experimentally 

determined BCF 

> 2,000, or if no 

experimentally 

BCF has been 

determined, log 

Pow;3

Toxicity 

Chronic 

NOEC < 0.01 

mg/L

Ozone N N Y Refer to 2.2.2、2.2.5 

Bromate ion Y N N Refer to 2.2.2、2.2.5 

Bromoform Y N N Refer to 2.2.2、2.2.5 

TRO N N N Refer to 6.3 

*: For the purpose of marine environmental risk assessment half-life data in fresh water and fresh 

water sediment can be over ruled by data obtained under marine conditions. 

6 Evaluation of the treated ballast water (G9: 5.2) 

6.1 Tests of the treated ballast water implemented for reapplication of 

Final Approval 

6.1.1 Summary of tests 

The following summarizes the additional tests implemented for reapplication of 

Final Approval. TRO concentration in the ballast water discharge immediately after post 

treatment by DWTT was automatically measured by TRO monitor in all the tests. 
MEPC 61/2/2 

Annex, page 31 

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

.1 Full-scale land-based acute toxicity test 

 Acute toxicity test in the Discharge Water Treatment Tank (DWTT) was 

performed with an improved activated carbon filling (brand name; 

SHIRASAGI WH2c8/32L) with higher oxidant removal performance. This 

test was done in the full-scale land-based test system (capacity; 200 m3/h) 

equipped with control panel and TRO monitor. The influent test water was 

in accordance with the required Guidelines (G8) test conditions for 

seawater and brackish water. Ballast water after post treatment (holding 

time; 0h) was used as the exposure water. 

.2 Full-scale land-based chronic toxicity test 

 Chronic toxicity test in the same test system and influent test water as the 

aforementioned full-scale land-based acute toxicity test was implemented 

by using test water in accordance with Guidelines (G8) conditions for 

seawater and brackish water and adopting treated ballast water after post 

treatment (holding time; 0 h) as exposure water. 

.3 Corrosion test 

The following two assessment tests in the same test system as the 

aforementioned full-scale land-based acute toxicity test were conducted by 

adopting the potentially most corrosive test water in this BWMS after Ozone 

injection: 

.1 corrosion test for ballast tank coatings; test to examine reduction of 

adhesion and deterioration of coated film in ballast tank; and 

.2 corrosion test for uncoated materials; test to examine corrosion of 

materials in contact with treated ballast water 

Test temperature for test 1 was 40°C to maximize the potential for corrosion 

of the various test pieces. Test 2 used 20°C and 40°C. The immersion

period for both tests was 97 days. 

.4 Long-term performance test for activated carbon filled in Discharge Water 

Treatment Tank 

Performance test to remove TRO and Relevant Chemicals in the DWTT 

was conducted by operating the same test system as the aforementioned 

full-scale land-based acute toxicity test every day with an extension 

of 508 hours operation. 

.5 Life determination test for activated carbon filled in Discharge Water 

Treatment Tank 

TRO in effluent was measured at multiple positions in the DWTT for the 

period of the aforementioned long term performance test for the activated 

carbon filled in the Discharge Water Treatment Tank, and a chronological 

change was examined during the transition of reduction in removal 

performance. Then, the time when TRO concentration in ballast water 

discharged from DWTT reached the maximum allowable discharge 

concentration of 0.2 mg/L (Cl2) was estimated as its life. 
MEPC 61/2/2 

Annex, page 32 

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

6.1.2 Test facility 

The full-scale land-based test system (200 m3/h) was used for every test performed. 

The following shows specification of each test facility. The activated carbon filled in the 

Discharge Water Treatment Tank (DWTT) has been changed to the material which is 

superior in removal performance of Relevant Chemicals. The TRO monitor system has also 

been installed. 

6.1.2.1 Full-scale land-based test facility 

This facility was installed to conduct Guidelines (G8) land-based test for the SP-Hybrid 

BWMS Ozone version with 200 m3/h treatment capacity. 

6.1.2.2 Equipment and operational condition of treatment system 

The equipment constituting the test facility is common to all the tests. In the case of system 

installed on board ship, a TRO monitor is set up to monitor ballast water both before and 

after the DWTT. If the TRO concentration in the ballast water discharge does not exceed the 

maximum allowable discharge concentration of 0.2 mg/L (as Cl2), ballast water is discharged 

without post treatment by the DWTT. If it exceeds 0.2 mg/L (as Cl2), ballast water flows into 

the DWTT. However, all the land-based tests for Final Approval were implemented by 

discharging treated ballast water directly into DWTT without storage in the ballast tank which 

would occur in actual operation during a voyage. Therefore, a TRO monitor prior to the 

DWTT was not required in the tests. 

6.1.3 Quality control of test 

The full-scale land-based toxicity tests (acute and chronic) were implemented in accordance 

with GLP standard of OECD "OECD principles of Good Laboratory Practice" (1977) under 

quality control by "Idea Co. Environment Creation Research Center" certified by 

ISO/IEC 17025 (JIS Q 17025). 

The corrosion test was implemented by QAPP based on ISO/IEC 17025 under ISO 9001 of 

"Nippon Paint Co.". 

The long-term performance test for activated carbon filled in the Discharge Water Treatment 

Tank (DWTT) was implemented in accordance with GLP standard of OECD "OECD 

Principles of Good Laboratory Practice" (1977) under quality control by "Chemicals 

Evaluation and Research Institute, Japan" certified by ISO/IEC 17025 (JIS Q 17025). 

The life determination test for activated carbon filled in DWTT was implemented by QAPP 

based on ISO/IEC 17025 under ISO 9001 of "Laboratory of Aquatic Science Consultants Co., Ltd.". 

The TRO analyser used for TRO measurement in various tests including the land-based test 

system was calibrated in accordance with ISO/IEC 17025 (JIS Q 17025) under the 

supervision of "Chemicals Evaluation and Research Institute, Japan". 
MEPC 61/2/2 

Annex, page 33 

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

6.2 Full-scale land-based acute toxicity test (G9: 5.2.2) 

The acute toxicity test for test organisms was performed with treated ballast water discharge 

generated in accordance with Guidelines (G8) of the SP-Hybrid BWMS Ozone version. 

The result of the tests reconfirms the conclusion that there is no acute toxicity in the ballast 

water discharge from the SP-Hybrid BWMS Ozone version. The concentration of Relevant 

Chemicals in the test sample was far less than the existing data on LC50 for acute aquatic 

toxicity reported in section 2.2.1 of this document. Though no data for TRO exists, TRO less 

than 0.02 mg/L (as Cl2) has no potential to create acute toxicity. 

6.3 Full-scale land-based chronic toxicity test (G9: 5.2.1) 

The chronic toxicity test for test organisms was performed with treated ballast water 

discharge generated in the same manner using the full-scale land-based test facility 

(seawater and brackish water) in accordance with Guidelines (G8). 

The result of the tests reconfirms the conclusion that the ballast water discharged from the

SP-Hybrid BWMS Ozone version is free from chronic toxicity. The concentration of Relevant 

Chemicals in the test sample was substantially lower than the acute aquatic toxicity 

described in section 2.2.1 of this document as well as the NOEC in the existing data related 

to chronic aquatic toxicity in section 2.2.2, which met the compliance. Though no data for 

TRO exist, TRO less than 0.02 mg/L (as Cl2) creates no chronic toxicity. 

6.4 Corrosion tests 

The corrosion tests were performed for the purpose of evaluating the corrosion effect on 

coated film in the ballast tank of the treated ballast water after Ozone injection and materials 

in contact with the treated ballast water. The following two tests were performed: 

.1 Corrosion test for ballast tank coatings 

 The purpose of this test is to assess the corrosion effect on corrosion 

resistant coated film, which protects the inside wall of the ballast tank. 

.2 Corrosion test for uncoated materials 

 The purpose of this test is to assess the corrosion effect on the piping in 

contact with the water treated by Ozone and materials constituting the 

system. 

As the result of the tests, the water treated by this BWMS is assessed to have corrosion 

effects within the allowable range on corrosion resistant coatings in the ballast tank. And also 

Ozone-treated water is deemed to have corrosion effect within the allowable range on all 

metallic and non-metallic materials used in the hull. 

TRO as environmental data of the test water was measured in a series of corrosion tests. 

Since Ozone treated water used in corrosion tests was sampled immediately after Ozone 

injection and contained high concentration of oxidant substances, concentrations in the 

range of 2 mg/L to 3.7 mg/L (as Cl2) were observed immediately after sampling. In most 

cases it maintained a high concentration more than 1 mg/L even three days later. There were 

some slight differences in the degradation rate, but this rate was almost same in all cases. 

The TRO concentration resulted in a 50% reduction 3 days (75 hours) later as dissolution 

advanced with the elapsed time. 
MEPC 61/2/2 

Annex, page 34 

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

6.5 Long-term performance test of Discharge Water Treatment Tank 

The purpose of this test is to examine the long term performance in removing Relevant 

Chemicals in the DWTT, which is essential equipment to ensure marine environmental safety 

in the SP-Hybrid BWMS Ozone version. This test was performed to evaluate a new activated 

carbon with a superior performance in removing oxidant substances (brand name: 

SHIRASAGI WH2c8/32L). 

It was confirmed that the removal performance of oxidant substances (particularly TRO) by 

the DWTT, which was improved by filling with the activated carbon with the superior oxidant

removal performance, decreased very little during the 508 hours accumulated operation. 

However, there were some concerns about bromoform which slightly increased according to 

the elapsed time. 

6.6 Life determination test for activated carbon filled in Discharge Water 

Treatment Tank (DWTT) 

The deterioration of removal performance the activated carbon was surveyed by measuring 

TRO in the DWTT during the long term performance test of Discharged Water Treatment 

Tank described in section 6.5. Based on the time when the TRO concentration in the ballast 

water discharged from DWTT reaches the maximum allowable discharge concentration 

of 0.2 mg/L (as Cl2), the life of the activated carbon was predicted. 

The slight increase in the TRO concentration in the DWTT was observed as time passed. 

However, the TRO concentration did not surpass the maximum allowable discharge 

concentration of 0.2 mg/L (as Cl2). 

In this test, the post treatment with the activated carbon was conducted immediately after the 

injection of Ozone (4 mg/L) without storage at the ballast tank. Compared with the actual 

ballast water management system on board, the activated carbon in the DWTT was tested 

under the stringent circumstance. 

In the case of a middle class bulk cargo vessel (Handy Max B.C.) in the unscheduled 

voyage, which is engaged in the longest annual ballasting among the representative vessels, 

she usually repeats approximately 15 hours of intake and discharge of the ballast water per 

one operation with 8 days interval. On the premise of 3 years as the longest interval of the 

routine inspection, an accumulated discharge time during that period amounts to 2070 hours. 

As the half-life of the TRO generated by this BWMS is about 3 days, it will theoretically 

disappear in 6 days. Therefore, the deterioration of removal performance the activated 

carbon is not expected for the operation of representative types of vessel. It is rational to 

define the life of activated carbon namely interval of exchange of the activated carbon as 

2070 hours of an accumulated ballast discharge time. 

6.7 Automatic measurement test of TRO in the ballast water discharge by TRO 

monitor 

During the total length of the test for the treated ballast water implemented for 

Final Approval, TRO in the ballast water discharge was surveyed and documented by the 

TRO monitor. If TRO exceeds the maximum allowable discharge concentration of 0.2 mg/L 

(as Cl2) as measured by the TRO monitor, the full-scale land-based test system is designed 

to stop automatically. 
MEPC 61/2/2 

Annex, page 35 

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

During the test period from 16 June to 21 October, 2009, the highest concentration 

of 0.16 mg/L (as Cl2) was detected four times, namely on 7 July, 9 September, 17 September 

and 21 September. On those days this result was not obtained in consecutive readings and 

there was a quick decline. 0.16 mg/L (as Cl2) detected four times was the highest value of 

TRO in all the tests including the measured data from other instruments besides the TRO 

monitor and was the maximum discharge concentration. 

Since all the data had showed less than 0.16 mg/L (as Cl2) as a maximum under such a 

severe condition which would maintain removal performance of this DWTT, even if the 

ballast water flows to the DWTT immediately after Ozone treatment, a sufficient performance 

to remove Relevant Chemicals by the DWTT was proved. 

6.8 Determination of holding time 

The SP-Hybrid BWMS Ozone version is a BWMS designed to remove residual Relevant 

Chemicals through the Discharge Water Treatment Tank (DWTT) in case TRO concentration 

surpasses the maximum allowable discharge concentration of 0.2 mg/L at time of discharge. 

By this treatment, the concentration of Relevant Chemicals in the ballast water discharge 

under any circumstances does not exceed the maximum allowable discharge concentration 

described in section 3.2.3 of this document namely 0.082 mg/L for bromate ion, 0.22 mg/L for 

bromoform and 0.2 mg/L (as Cl2) for TRO. These maximum allowable discharge 

concentrations of Relevant Chemicals were defined based on the results of various tests, 

which specified no holding time. Therefore, no required holding time is specified for operation 

of this BWMS. 

6.9 Risk characterization and analysis 

6.9.1 Reaction with organic matter (G9: 4.2.1.3) 

The concern that halogenated hydrocarbons could be formed at the time of reaction with 

organic matter was examined by analysing untreated effluent prior to treatment and ballast 

water discharge at the test of the previous application (MEPC 59/2/1). 

As a result, it was confirmed as a result of this analysis that no halogenated hydrocarbon 

existed in the ballast water discharged from this BWMS. 

6.9.2 Characterization of degradation route and rate (G9: 5.3.5) 

Degradation of Active Substances and Relevant Chemicals under abiotic and biotic 

circumstances is described in section 2.4.1 of this annex. This BWMS is designed to 

completely remove Ozone (the Active Substance) either by the gas/liquid separation tank or 

by other treatment. As the half-life of bromate ion is longer than 40 days, it barely dissolves 

in the Discharge Water Treatment Tank (DWTT) and its maximum discharge concentration 

is 0.082 mg/L. Though the half-life of bromoform is also long as 32 days to 185 days, the 

maximum concentration generated by Ozone injection was as low as 0.22 mg/L. As most of it 

is removed by the post treatment of the DWTT, discharge concentration is lower 

than 0.034 mg/L provided that the adsorption capability of the activated carbon in the DWTT 

is maintained. As the half-life of TRO is about 3 days, it is removed by the DWTT. 
MEPC 61/2/2 

Annex, page 36 

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

6.10 Prediction of discharge and environmental concentrations 

Predicted environmental concentration (PEC) for bromate ion, bromoform and TRO of 

Relevant Chemicals in the ballast water discharged from the SP-Hybrid BWMS Ozone 

version was calculated by using MAMPEC model version 2.0 targeting on Tokyo Bay. 

The predicted environmental concentration (PEC) is as shown below: 

.1 PEC of bromate ion; 0.00603 μg/L; 

.2 PEC of bromoform: 0.0131 μg/L; and 

.3 PEC of TRO (as BrO3-): 0.0207 μg/L. 

Table 6.10-1: PEC calculation results in designated sea area using MAMPEC model 

version 2.0 

6.11 Assessment of potential for bioaccumulation 

Log Pow of Relevant Chemicals is -7.18 for bromate ions and 2.4 for bromoform as shown in 

section 2.4.2 of this document. Since TRO indicates total oxidants, direct octanol/water 

partition coefficient does not exist. However, since its half-life is short, logPow will be lower 

than three, which is an index of bioaccumulation potential. Therefore it is considered that 

there is no risk of bioaccumulation by Relevant Chemicals discharged from the SP-Hybrid 

BWMS Ozone version. 

6.12 Effects assessment 

The maximum discharge concentration of Relevant Chemicals discharged from the

SP-Hybrid BWMS Ozone version is 0.82 mg/L for bromate ion, 0.22 mg/L for bromoform 

and 0.16 mg/L (as Cl2) for TRO. And with reference to TRO, it is managed in actual operation 

by defining 0.2 mg/L (as Cl2) as the maximum allowable discharge concentration. 

In contrast, as described in section 2.2.1 of this document, acute toxicity values for bromate 

ion and bromoform substantially surpass these discharge concentrations. Chronic toxicity 

NOEC of bromate ion and bromoform as described in section 2.2.2 of this document also 

substantially surpass these discharge concentrations. Acute toxicity tests as well as chronic 

toxicity tests for the ballast water discharged from this BWMS resulted in no toxic effects on 

the ballast water discharge. 

As summarized in section 6.1.1 of this document, in view of characteristics of discharged 

Relevant Chemicals, bioaccumulation is unlikely to occur and no toxic effects accumulated 

through the food-web are considered to exist. 

From the standpoint of the above view, Relevant Chemicals discharged from this BWMS are 

unlikely to cause effects in either the short term or the long term. 

PEC of Relevant Chemicals (μg L) 

Bromate ion Bromoform TRO (as BrO3

-

) 

Maximum concentration 0.00102 0.0226 0.0350 

95% concentration 0.00940 0.0207 0.0322 

Average concentration 0.00603 0.0131 0.0207 

Median concentration 0.00604 0.0130 0.0207 

Minimum concentration 0.00131 0.0028 0.0044 
MEPC 61/2/2 

Annex, page 37 

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

6.13 Effects on aquatic organisms 

6.13.1 Estimated PNEC 

The PNEC of Relevant Chemicals discharged from the SP-Hybrid BWMS Ozone version is 

estimated as follows: 

.1 Bromate ion: LC50 or EC50 have been obtained for three types of marine 

species and the lowest concentration is 30 mg/L of 96h-EC50. By setting 

the Assessment Factor in this case to 1000 for long term and 100 for short 

term, the results obtained are 30 μg/L for PNEC long and 300 μg/L for 

PNEC short. 

.2 Bromoform: LC50 or EC50 have been obtained for five types of marine 

species and 4 types of fresh water species in total and the lowest 

concentration is 7.1 mg/L of 96h-LC50. By setting the Assessment Factor 

in this case to 1000 for long term and 100 for short term, the results are 7.1 

μg/L for PNEC long and 71 μg/L for PNEC short. 

.3 Total Residual Oxidant (TRO): As TRO represents the total amount of 

oxidants, there exist no toxicity data. Therefore, PNEC was calculated by 

using the results of acute toxicity tests and chronic toxicity tests for three 

marine species as described in sections 6.2 and 6.3 of this document. 

No effect of acute toxicity was observed in acute toxicity tests under the 

maximum concentration of 0.02 mg/L (as Cl2). This maximum concentration 

corresponds to 0.035 mg/L (as BrO3−). If the assessment factor is set to 10, 

PNEC short results in 3.5 μg/L (as BrO3−). Chronic toxicity tests resulted in 

evaluation of 100% (no dilution) concentration for the ballast water 

discharge. The maximum discharge concentration was 0.02 mg/L (as Cl2). 

This concentration corresponds to 0.035 mg/L (as BrO3−). If the assessment 

factor is set to 100, PNEC long results in 0.35 μg/L (as BrO3−). 

6.13.2 PEC/PNEC ratio 

Based on the PEC obtained in paragraph 6.10.4 of this document and the PNEC estimated 

in paragraph 6.13.1 of this document, PEC/PNEC was calculated. The results are shown in 

Table 6.13-1. 

PEC/PNEC of Relevant Chemicals generated from the SP-Hybrid BWMS Ozone version 

were far lower than 1. 

Table 6.13-1: PEC, PNEC and PEC/PNEC ratio 

PNEC (μg/L) PEC/PNEC Relevant Chemicals PEC 

(μg/L) long short long short 

Bromate ion 0.00603 30 300 0.00020 0.00002 

Bromoform 0.0131 7.1 71 0.0018 0.0001 

Total Residual 

Oxidants 

(TRO as BrO3

-

) 

0.0207 0.35 3.5 0.0591 0.0059 
MEPC 61/2/2 

Annex, page 38 

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

6.14 Effects on sediment 

Adsorption and accumulation on sediment of Relevant Chemicals discharged from the 

SP-Hybrid BWMS Ozone version are not expected for the reasons described in section 2.2.4 

of this document. Therefore, it is considered that these substances have no effect on 

sediment. 

6.15 Comparison of effect assessment with discharge toxicity 

As described above, the evaluation of the treated ballast water concluded in sections 6.9 

to 6.14 of this document coincides with the evaluation results that neither acute toxic nor 

chronic toxic effects were observed in the ballast water discharged from the SP-Hybrid 

BWMS Ozone version in various toxicity tests carried out for the treated ballast water. 

7 RISK ASSESSMENT 

7.1 Risk to safety of ship 

7.1.1 Increased corrosion 

The materials which are subject to corrosion effects were selected as follows as an 

anti-corrosion measure in this BWMS. Selection of these materials ensures prevention of 

corrosion effects. Consideration shall be given to prevent galvanic corrosion between 

different kinds of metal. 

.1 Ozone gas line 

 .1 Piping from Ozone Generator outlet to Ozone Injector inlet 

Stainless steel pipe (SUS304) is used as its Ozone resistance is 

essential under high concentration of Ozone gas. 

 .2 Piping from Gas/Liquid Separation Tank outlet to Waste Ozone 

Destruction Unit inlet 

Though the Ozone gas concentration is low (0.2 ppm in the 

land-based test), its influence on shipboard personnel is serious if 

a leak occurs as a result of corrosion. For safety, stainless steel 

pipe (SUS304) or pipe with an Ozone-resistant coating is used. 

 .3 Ozone Generator 

Stainless steel (part of Ozone generation; SUS316L, piping; 

SUS304) is used in the part of Ozone generation and piping. 

 .4 Waste Ozone Destruction Unit 

Though the Ozone gas concentration is low (0.2 ppm in the 

land-based test), stainless steel (SUS316L) is used in 

consideration of wet and decomposition heat. 
MEPC 61/2/2 

Annex, page 39 

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

 .2 Ozone seawater line 

.1 Piping from Ozone Injector outlet to Gas/Liquid Separation Tank 

inlet 

 For corrosion resistance to seawater containing a high 

concentration of Ozone, stainless steel pipe (SUS316) or pipe with 

an Ozone-resistant coating is used. 

.2 Ozone Injector 

 As the Ozone Injector contacts with seawater containing a high 

concentration of Ozone, stainless steel (SUS316) is used. 

.3 Ballast Pump (including valve, etc.) 

 As the Ballast Pump feeds seawater containing a high 

concentration of Ozone, Ozone-resistant bronze or stainless steel 

(SUS316) is used for the pump casing, impeller and other parts in 

contact with the seawater. For valves, etc., the same materials are 

used. 

.4 Special Pipe (slit plate) 

 For corrosion resistance to seawater containing a high 

concentration of Ozone seawater, stainless steel (SUS316) is 

used. 

.5 Gas/Liquid Separation Tank 

 For corrosion resistance to seawater containing a high 

concentration of Ozone, stainless steel (SUS316) or steel with an 

Ozone-resistant coating is used. 

.3 Relevant Chemicals seawater line 

.1 Piping from Ozone Injector outlet to Gas/Liquid Separation Tank 

inlet (same as in above paragraph 7.1.1.2.1). 

.2 Piping from Gas/Liquid Separation Tank outlet to ballast tank inlet 

Corrosion influence of Relevant Chemicals is slightly higher than 

seawater. Galvanized pipe or pipe with an epoxy coating is used 

(the same as usual for seawater pipes). 

.3 Piping from ballast tank outlet to Discharge Water Treatment Tank 

Same as in above paragraph 7.1.1.3.2. 

.4 Ballast tank 

 Influence of Relevant Chemicals only. Steel with epoxy coating is 

used (the same as usual for seawater tanks). 
MEPC 61/2/2 

Annex, page 40 

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

 The "Performance Standard for Protective Coatings of dedicated 

seawater ballast tanks on all new ships and of double-side skin 

spaces of bulk carriers" ("PSPC") shall be applied to all new ships. 

Since an epoxy coating will be used in ballast tanks according to 

"PSPC", there will not be any problem. 

.5 Discharge Water Treatment Tank 

Influence of Relevant Chemicals only. However, as activated 

carbon is contained inside, a synthetic resin lining or rubber lining 

should be applied to prevent galvanic corrosion. 

7.1.2 Fire and explosion 

Generally speaking, the major risks with ships are fire and flood. Regarding fire, safety is 

enhanced by implementing the following measures to reduce the risk: 

.1 in case of fire occurring in the engine room or in another room where the 

Ozone Generator is installed, the Ozone Generator can be stopped from 

outside the room; and 

.2 in case of a fire alarm, the electric power supply to Ozone Generator will be 

shut down immediately to halt production of Ozone which would otherwise 

help the fire. 

7.1.3 Storage and handling of the substances 

The SP-Hybrid BWMS Ozone version is a system which uses Ozone as the 

Active Substance generated by the Ozone Generator Module installed on board. There is no 

need to store and handle the Active Substance on board, which reduces the risk. 

7.1.4 Contact with, or inhalation of, process products 

Ozone (as Active Substance) and Relevant Chemicals may cause the following potential 

risks to shipboard personnel when this system is operated: 

 .1 hazard to respiratory organs by inhalation of Ozone; and 

 .2 hazard to the eyes and dermis by contact with Ozone and 

Relevant Chemicals. 

This system is applied with the following measures to prevent all potential risks. Bromoform 

is volatile and causes exposure effect to shipboard personnel, as mentioned by 

GESAMP-BWWG when reviewing the application for Basic Approval (MEPC 55/2/16, annex 5). 

The air in ballast tank was sampled immediately following operation of this system, and the 

bromoform concentration in the sampling air was analysed. The result showed the value to 

be under lower limit of detection of 0.019 μg/m3 and proved that bromoform had no exposure 

effect on shipboard personnel. 
MEPC 61/2/2 

Annex, page 41 

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

7.1.5 Noise 

The noise of the SP-Hybrid BWMS Ozone version installed on board was measured when 

the system was operated. The results were below 110 dB(A), which is the upper limit for 

machinery space (not continuously manned ) and the safety to shipboard personnel could be 

confirmed. 

7.2 Risk to human health 

7.2.1 Health effects in humans (G9: 5.3.12) 

The health effect scenario in humans (except for shipboard personnel) is estimated by 

consideration of the seafood web and the ecosystem. As the ballast water discharged from 

this system is unlikely to cause any impact on the environment, however, this route has a 

little risk. As described in section 7.1.4, bromoform is potentially dissipated from the ballast 

tank. When the bromoform was measured, it was under lower limit of detection 0.019 μg/m3 

and was not at a level to affect human health. Therefore, volatile bromoform has no risk to 

human health. 

Though residual bromate ion and TRO in the ballast water are unlikely to affect human health 

during inspection of the ballast tank, protective equipment should be worn during inspection 

to avoid any risk. 

7.2.2 Human Exposure Scenario (HES) (G9: 6.3.3) 

A third party organization conducted an assessment of the exposure to humans of the 

Active Substance and Relevant Chemicals of this system. 

The upshot is that the results of the investigation into the toxicity and exposure to Ozone as 

the Active Substance and to the Relevant Chemicals shows that the risk to human health is 

low for all substances and that no effect on human health is expected. 

7.2.3 Conclusion 

The results of the investigation into the toxicity and exposure to Ozone as the 

Active Substance and to the Relevant Chemicals shows that the risk to human health is low 

for all substances and that no effect on human health is expected. 

7.3 Risk to the aquatic environment 

As summarized in section 6 of this document, ballast water discharged from this system has 

no potential effect on the environment. 

8 CONCLUSION 

The SP-Hybrid BWMS Ozone version uses extremely oxidizing Ozone as the Active 

Substance and Ozone reacts with ballast water to generate the Relevant Chemicals 

consisting of bromate ions, bromoform and Total Residual Oxidants (TRO). However, as this 

BWMS has thorough safety measures for Ozone which are put in place onboard a vessel, 

safety to the vessel and her shipboard personnel is completely secured. Furthermore, as the 

concentration of generated Relevant Chemicals can be reduced through the Discharge 

Water Treatment Tank, the potential impact to public health and to the environment in the 

ambient waters of the ballast discharge is deemed almost negligible. Therefore, this system 

is considered to deserve Final Approval under Procedure (G9). 
MEPC 61/2/2 

Annex, page 42 

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

REFERENCES 

ACGIH 2001b; American Conference of Governmental Industrial Hygienists (2001) 

Ozone.Documentation of the threshold limit values and biological exposure indices, 7th ed. 

Cincinnati, OH. 

Bouwer E.J. and McCarty P.L. (1983a) Transformations of 1- and 2-carbon halogenated 

aliphatic organic compounds under methanogenic conditions. Appl. Environ. Microbiol, 

45,1286-1294. 

Bouwer E.J. and McCarty P.L. (1983b) Transformations of halogenated organic compounds 

under denitrification conditions. Appl. Environ. Microbiol. 45, 1295-1299. 

ECOTOX DATA BASE (U.S EPA, 2007a). 

Fisher D.J., Burton D.T., Yonkos L.T., Turley S.D.andZiegler G.P. (1999) The relative acute 

toxicity of continuous and intermittent exposures of chlorine and bromine to aquatic 

organisms in the presence and absence of ammonia. WATER RESEARCH, 33, 

760-768. 

Hijnen W, R Voogt, HR Veenendaal, H van der Jagt and D van der Kooij (1994), Bromate 

Reduction by Denitrifying Bacteria; Appl. Environ. Microbiol., Jan 1995, Vol 61, No. 239-244. 

NITE 2007; National Institute of Technology and Evaluation, Biodegradation and 

Bioconcentration of Existing Chemical Substances under the Chemical Substances Control 

Law, http://www.safe.nite.go.jp/data/hazkizon/pk_e_kizon_disp.html?k_no=0657. 

Siddiqui, M.S., Amy, G.L. and Rice, R.G., 1995. Bromate ion formation: A critical review. 

Journal of American Water Works Association 87, pp. 58–70. 

Siddqui M S., Thai W., Amy G., Mysore C. ( ) 1996 Bromate ion removal by activated carbon 

Water Research Volume 30, Issue 7, July 1996, Pages 1651-1660. 

SRC Database; Bromate ion. 

Tabak H.H., Quaze S.A., Mashni C.I. and Barth E.F. (1981) Biodegradability studies with 

organic priority pollutant compounds. J. Water Pollut. Control Fed. 53, 1503-1518. 

WHO (1996) Guidelines for drinking- water quality, Second Edition Volume 2, pp 851. 

http://www.who.int/water_sanitation_health/dwq/en/2edvol2p1.pdf. 

* * * 
MEPC 61/2/2 

Annex, page 43 

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

APPENDIX 1 

STATEMENT 

Example; Acute and chronic toxicity test for the treated water discharge (seawater, treated 

before discharge, holding time 0 Day) with Special Pipe Ballast Water Treatment System 

(combined with Ozone Treatment Version) using 3 kinds of organism 

* * * 
MEPC 61/2/2 

Annex, page 44 

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

APPENDIX 2 

QUALITY ASSURANCE STATEMENT 
MEPC 61/2/2 

Annex, page 45 

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

___________