2008-04-02 23:56:54 -

- Nalco Holding Company (NYSE:NLC) today announced it will release its first-quarter 2008 sales and earnings results after market close on April 29.

At 10 a.m. ET on April 30, the Company will hold a conference call and live audio-only Webcast led by Nalco Chairman, President and Chief Executive Officer J. Erik Fyrwald and other senior management team members

to discuss these results.

Date: 4/30/2008

Start Time: 10 a.m. ET / 9 a.m. CT / 8 a.m. MT / 7 a.m. PT

Length: 60 minutes

Dial-in Telephone Number: 1- 719-325-4813

Confirmation Code: 4436695

To help ensure the conference call begins in a timely manner, please dial in 5 to 10 minutes prior to the scheduled start time on April 30.

The audio-only Webcast will be available through the Investor Relations section of Nalco's Web site, www.nalco.com. Following the live event, an archived version of the Webcast will also be available on the Nalco Web site under Investor Relations, Event Calendar.

About Nalco

Nalco is the world's leading water treatment and process improvement company, delivering significant environmental, social and economic performance benefits to our customers. We help our customers reduce energy, water and other natural resource consumption, enhance air quality, minimize environmental releases and improve productivity and end products while boosting the bottom line. Together our comprehensive solutions contribute to the sustainable development of customer operations. More than 11,500 Nalco employees operate in 130 countries supported by a comprehensive network of manufacturing facilities, sales offices and research centers to serve a broad range of end markets. In 2007, Nalco achieved sales of more than $3.9 billion. For more information visit www.nalco.com.

Nalco Holding Company
Media Contact:
Charlie Pajor, 630-305-1556
cpajor@nalco.com
or
Investor Contact:
Mike Bushman, 630-305-1025
mbushman@nalco.com