NEW YORK--(BUSINESS WIRE)--DWS, one of the world's leading asset managers, announced today that a sustainable investments private equity fund advised by the firm has invested $23 million USD in International Environment Group Limited (IEG). IEG is a leading environmental service provider focusing on waste treatment and waste management. The company has supplied environmental equipment and services in more than 30 countries over the past 20 years, and is now applying its expertise and experience.