New York's health commissioner is still declining to speculate when his agency will finish a review of the health effects of hydraulic fracturing for natural gas.

Dr. Nirav Shah tells legislators Monday that conclusion is "not in the near future where I can predict it."

He says the review involves many human health studies from around the country, including several published last year, evolving drilling technology and the effort to determine its likely effect in New York's Marcellus Shale formation.

It has involved up to two dozen staff over two years, already cost hundreds of thousands of dollars, and is meant to answer the health questions asked by the state's conservation commissioner, who has authority to regulate drilling.

Shah says Gov. Andrew Cuomo has made no suggestions about the outcome.