A.M. Best Downgrades and Withdraws Ratings of Quanta Capital Holdings Ltd

Business Wire, June 7, 2006

OLDWICK, N.J. -- A.M. Best Co. has downgraded the financial strength ratings (FSR) to B (Fair) from B (Very Good) and the issuer credit ratings (ICR) to "bb" from "bbb" for the insurance/reinsurance subsidiaries of Quanta Capital Holdings Ltd. (Quanta) (NASDAQ: QNTA) (Hamilton, Bermuda). These rating actions apply to Quanta Reinsurance Ltd. (Quanta Re) (Hamilton, Bermuda), its subsidiaries and Quanta Europe Ltd. (Dublin, Ireland). A.M. Best has also downgraded Quanta's ICR to "b" from "bb" and the securities rating to "ccc" from "b " for its $75 million 10.25% Series A non-cumulative perpetual preferred shares. All ratings have been removed from under review with negative implications and assigned a negative outlook.

Subsequently, all ratings of Quanta will be withdrawn and the FSRs will be assigned a rating of NR-4 (Company Request) in response to management's request that Quanta be removed from A.M. Best's interactive rating process.

A.M. Best maintained a conservative view in evaluating the group's run-off given the potential for catastrophe and non-catastrophe related adverse reserve development, exposure to potential 2006 catastrophes due to the risk attaching nature of the remaining reinsurance business and execution risk with regard to dismantling the existing infrastructure.

These rating actions follow A.M. Best's previous downgrading of Quanta's ratings on March 2, 2006 after Quanta reported a significant fourth-quarter 2005 net loss.

The FSRs of B (Very Good) and the ICRs of "bbb" have been downgraded to B (Fair) and "bb", respectively, for the following insurance/reinsurance subsidiaries of Quanta Capital Holdings Ltd.:

--Quanta Reinsurance Ltd.

--Quanta Europe Ltd.

--Quanta Indemnity Company

--Quanta Reinsurance U.S. Ltd.

--Quanta Specialty Lines Insurance Company

The ICR of "bb" has been downgraded to "b" for Quanta Capital Holdings Ltd.

The following securities' rating has been downgraded:

Quanta Capital Holdings Ltd.--

--to "ccc" from "b " on $75 million 10.25% Series A non-cumulative perpetual preferred shares

Subsequently, all the above ratings will be withdrawn.

For Best's Debt Ratings, all other Best's Ratings, an overview of the rating process and rating methodologies, please visit www.ambest.com/ratings.> A.M. Best Co., established in 1899, is the world's oldest and most authoritative insurance rating and information source. For more information, visit A.M. Best's Web site at www.ambest.com.