By GREGORY N. HEIRES

Mail ballots went out today  to more than 90,000 members for a vote on a contract extension to protect the union’s popular prescription drug plan, which has been rocked in recent years by the pharmaceutical industry’s pursuit of excessive profits.

The contract extension, which the union and city agreed to in January, will enable the DC 37 Health & Security Plan to continue to provide stable benefits to members and retirees.

During the past eight years, the pharmaceutical industry has raised prescription drug prices by 105 percent. Today, prescription drugs consume 76 percent of the costs of the welfare fund, which also covers the dental benefit and other benefits managed by the plan.

The DC 37 Health & Security Plan faces a $55 million deficit.

The contract extension is one of a number of critical steps the union is taking to protect the drug benefit.

Under the DC 37 Constitution, the contract extension must be ratified by the membership. Ballots are due back Friday, March 10.

The agreement between the union and the city would extend the current 2010-17 agreement from July 2 to Sept. 25. All other terms of the contract will remain the same.

The union and the city negotiate welfare benefit funding during collective bargaining. Benefits are funded with the pot of money negotiated at the bargaining table. (Union dues do not pay for benefits.)

“The Fund urgently needs additional, recurring revenue in order to continue providing benefits to our members,” said DC 37 Executive Director Henry Garrido. “It’s a good deal for the hard-working members of District Council 37.”

Garrido urged members to fill out and return the ballot to AAA  and to encourage coworkers to do so as well.

Willie Chang, administer of the DC 37 Health & Security Plan, said that without additional funding provided by the contract extension, the plan would be unable to cover the solvency of all of its benefits.

An independent monitor will tally the vote and report the results to the union.

The union’s welfare benefits are fully-funded by the city’s annual payment, which under the contract extension will increase from $1,575 to $1,775 for each member and retiree.

The extension covers DC 37 members working in mayoral agencies, NYC Health+Hospitals, the Dept. of Education and the New York City Housing Authority.

Members at the School Construction Authority, NYC Transit, and the Triborough Bridge and Tunnel Authority will be asked to vote on a similar contract extension.

City University of New York employees and Local 924 members have already approved contracts that include the extra $200 payment. Some DC 37 members are covered by contracts with different expiration dates. Those contracts will similarly be extended to two months and 23 days.

Members should call 1-800-529-5218 if they don’t receive the mail ballot.