PORTLAND, Maine (AP) — A team from the University of Southern Maine and the conservation organization Ocean Alliance is headed to the Gulf of Mexico to take tissue samples from whales to determine what toxic substances they’ve been exposed to.

They’ll also be doing cell cultures to find out what it takes to make whales sick.

Scientific Director John Wise says the project was in the works before the massive oil spill, but that it has taken on greater urgency because of the spill.

Wise says researchers will use special equipment to take tissue samples from four types of whale: humpbacks, sperm, Bryde’s (BROO’-tah) and killer whales.

The team is leaving Saturday aboard the Ocean Alliance’s laboratory-equipped sailboat Odyssey.