CORPORATE ANNOUNCEMENT

22 December, 2004

MOL Develops A New Environment-Friendly Technology for Ballast Water Purification

-- MOL technologies continue to meet the challenge of protecting the marine environment --

TOKYO - Mitsui O.S.K. Lines, Ltd. (MOL; President: Akimitsu Ashida) today announced that they have ensured the company's compliance with new IMO ballast water discharge standards (plankton). The filter ensures removal of marine organisms and features a unique cleaning system that prevents clogging.

Background and results (summary)

MOL has conducted research and development on a filter-based ballast water treatment system since 2003. Following the International Maritime Organization (IMO)'s adoption of an international convention on the control and management of ships' ballast water in February 2004, the company began testing its filter-based ballast water treatment system to ensure compliance with the new standards. MOL's new system achieved the results shown below. (Refer the chart below for discharge standards.)

Number of aquatic organisms over 50µm in minimum dimension: 0 per m3 (October 2004)
Number of aquatic organisms from 10µm to 50µm in minimum dimension: 6 per ml (October 2003)

Aquatic species Discharge standards

Plankton 1) Minimum dimension over 50µ
(mainly zooplankton) Less than 10 per m³

2) Minimum dimension from 10µ to 50µ
(mainly phytoplankton) Less than 10 per ml

Bacteria Toxicogenic Vibrio cholerae (O1 and O139) Less than 1 cfu (=colony forming unit) per 100ml
or less than 1cfu per 1g zooplankton samples

Escherichia coli Less than 250 cfu per 100ml

Intestinal Enterococci Less than 100 cfu per 100ml

Features of MOL's filter-based ballast water treatment system

MOL has applied for a patent on its system, which offers these features:

Incoming ballast water is filtered, removing most aquatic organisms before the water enters the ballast tanks.
MOL's proprietary new cleaning method uses both back-flushing and high-pressure jets to remove foreign matter from clogged filters.
Large filters are adequate for various types of vessels, including large ships.

MOL's future development policies

The tests outlined above demonstrate that the MOL system ensures compliance with IMO standards for plankton. In the future, the company will look at ways to combine the system with another system to ensure more effective removal of bacteria, which is difficult to filter because of its small size. MOL will also examine ways to expand the system's treatment capacity to at least 200m3 per hour to ensure approval under ballast water management treaty guidelines that are now on the table.

The treaty may be applicable to newly built vessels after 2009 if all goes smoothly. Shipping companies face an urgent need to develop a ballast water treatment device that conforms to these new standards. MOL continues to develop the system for practical use in adherence with the purpose of the ballast management treaty and believes it is an appropriate method for ship owners.

Results of two years of testing

The company conducted the following tests to confirm the effectiveness of its filter-based ballast water treatment system:

The tests were conducted at the MOL Yokohama Honmoku Terminal D5 berth.
Seawater surrounding the berth was pumped through the filter to measure size and numbers of plankton in the filtered water. The Marine Biological Research Institute of Japan Co., Ltd. conducted the measurements.
An exclusive filter made by Fuji Filter MFG. Co., Ltd. with a mesh size of 5µm was used for the tests.
During tests in October 2004, over 1m3 of natural seawater was sequentially pumped through the filter to meet IMO standards adopted in February 2004. The seawater contained about 470,000 organisms in minimum dimension (50µm or larger) per 1m3, but there were no species of that size in the water after treatment (Treatment ratio 100%).

Date of test Targets for purification Number of plankton before purification Number of plankton after purification

October 2003 Plankton in minimum dimension from 10μ to 50μ 102-382 (average 254) per ml 4-7 (average 6) per ml

March 2004 Plankton in minimum dimension from 10μ to 50μ 137-181 per ml 2.6-9.9 per ml

October 2004 Plankton in minimum dimension over 50μ 470,000 per m³ 0 per m³

Note: The test in October 2003 was the result of four samplings.
The test in March 2004 was the result of five samplings.

For further information, please contact:

    Mitsui O.S.K. Lines, Ltd.
    Masaaki Yutani
    Manager, Ship Planning and Development Group, Technical Division
    Tel: 81-3-3587-7061
    Fax: 81-3-3587-7722
    Email: spdmo@mail.mol.co.jp

	Aquatic species	Discharge standards
Plankton	1) Minimum dimension over 50µ (mainly zooplankton)	Less than 10 per m³
Plankton	2) Minimum dimension from 10µ to 50µ (mainly phytoplankton)	Less than 10 per ml
Bacteria	Toxicogenic Vibrio cholerae (O1 and O139)	Less than 1 cfu (=colony forming unit) per 100ml or less than 1cfu per 1g zooplankton samples
	Escherichia coli	Less than 250 cfu per 100ml
	Intestinal Enterococci	Less than 100 cfu per 100ml

Date of test	Targets for purification	Number of plankton before purification	Number of plankton after purification
October 2003	Plankton in minimum dimension from 10μ to 50μ	102-382 (average 254) per ml	4-7 (average 6) per ml
March 2004	Plankton in minimum dimension from 10μ to 50μ	137-181 per ml	2.6-9.9 per ml
October 2004	Plankton in minimum dimension over 50μ	470,000 per m³	0 per m³