BOSTON (AP) -- Massa chusetts Public Health Com mis sioner John Auerbach resigned Monday in the wake of a growing investigation into a chemist whose alleged mishandling of drug samples led police to shut down the state crime lab and re-examine tens of thousands of drug cases.

Auerbach said it's clear that there was "insufficient quality monitoring, reporting and investigating on the part of supervisors and managers" at the lab, which had been overseen by the Depart ment of Pub lic Health before being transferred to state police as part of a budgetary realignment.

"What happened at the drug lab was unacceptable and the impact on people across the state may be devastating, particularly for some within the criminal justice system." Auerbach said in a written statement Monday. "We owe it to ourselves and the public to make sure we understand exactly how and why this happened."

Auerbach said he will continue to work with investigators.

Gov. Deval Patrick accepted the resignation, calling the failures at the lab serious. He said the actions and inactions of lab management compounded the problem.

No Berkshire impact

Berkshire District Attorney David F. Capeless has said he is confident there will be no impact in the Berkshires because testing of samples from local cases occured at a different lab.

Authorities have not released specific details about what chemist Annie Dookhan allegedly did.

But in a letter sent last week to defense attorneys around the state, Max Stern, the president of the Massachusetts Assoc iation of Criminal Defense Lawyers said he was told in a meeting with Patrick and other administration officials that the chemist is accused of deliberately tampering with some drug samples, including the weight of the samples, which can affect the length of prison sentences given to people convicted of drug offenses.

"The lab is apparently unable to tie this conduct to specific cases. And the conduct appears to have occurred over a prolonged period. There are also questions about supervision of the lab generally, failure to follow and update protocols through out the lab, the quality of the analyst's work due to the exceptional number of analyses she conducted, and the particular analyst's sign-off on the work of others. "

‘Breakdown in oversight'

State police took over the lab July 1 and closed it last month after discovering the extent of Dookhan's alleged mishandling of drug samples.

"The commissioner recognizes that, as the head of DPH, he shares accountability for the breakdown in oversight," Patrick said in a statement.

Patrick also defended Auer bach's overall record at the department during the past six years, calling his commitment to the common good and the people of Massa chusetts unquestioned.