SAFC, a leading custom chemical manufacturer and a division of Sigma-Aldrich Corporation (NASDAQ: SIAL - News), announced that it has broken ground on a major expansion at its Madison, Wisconsin, facility. The 38,000 square foot expansion will more than double the size of its existing 23,500 square foot building.

The expansion is being driven by an increase in demand for custom chemical manufacturing services for highly potent APIs, including category III and category IV compounds. "The expansion further positions us to provide unparalleled service in the high potency API manufacturing market," said Frank Wicks, President of Sigma-Aldrich Fine Chemicals. "Initiating the Madison expansion reinforces the decision we made back in June when we acquired Tetrionics. The new addition allows us to continue to grow our high potency business and provides resources that enables us to meet the needs of current and future customers."

The new two-story addition will include:

The company anticipates the expansion will be complete in early 2006.

About SAFC:

SAFC is the custom manufacturing group within Sigma-Aldrich that focuses on both biochemical production and the manufacturing of complex, multi-step organic synthesis of APIs and key intermediates. SAFC has manufacturing facilities around the world dedicated to providing manufacturing services for companies requiring a reliable partner to produce their custom manufactured materials.

About Sigma-Aldrich:

Sigma-Aldrich is a leading Life Science and High Technology company. Our biochemical and organic chemical products and kits are used in scientific and genomic research, biotechnology, pharmaceutical development, the diagnosis of disease and as key components in pharmaceutical and other high technology manufacturing. We have customers in life science companies, university and government institutions, hospitals, and in industry. Over one million scientists and technologists use our products. Sigma-Aldrich operates in 34 countries and has over 6,000 employees providing excellent service worldwide. We are committed to the success of our Customers, Employees and Shareholders through leadership in Life Science, High Technology and Service.

Cautionary Statement:

This release contains forward-looking statements relating to future performance, goals, strategic actions and initiatives and similar intentions and beliefs and other statements regarding Sigma-Aldrich�s expectations, goals, beliefs, intentions and the like regarding future sales, earnings and other matters. These statements involve assumptions regarding Company operations, investments and conditions in the markets the Company serves. Although the Company believes its expectations are based on reasonable assumptions, such statements are subject to risks and uncertainties, including, among others, certain economic, political and technological factors. Actual results could differ materially from those stated or implied in this news release, due to, but not limited to, such factors as (1) changes in pricing and the competitive environment, (2) other changes in the business environment in which the Company operates, (3) uncertainties surrounding government healthcare reform, (4) government regulations applicable to the business, (5) the impact of fluctuations in foreign currency exchange rates, and (6) the ability to retain customers, suppliers and employees. (7) the success of research and development activities and (8) the impact of acquisitions and success in integrating and obtaining projected results from the acquisitions. The Company does not undertake any obligation to update these forward-looking statements.