A flammable chemical was spilled at Morgan's Point on the Houston Ship Channel on Monday when two vessels collided.

Two tanks on board the Carla Maersk, a 600-foot chemical tanker, were punctured when it collided with the Conti Peridot, a 623-foot bulk carrier, USA Today reported. The Danish-flagged vessel was carrying approximately 216,000 barrels of Methyl tertiary-butyl ether, or MTBE, a gasoline additive.

An unknown quantity of the chemical leaked into the water, prompting the Coast Guard to close the Houston Ship Channel in both directions between light 86 and the Fred Hartman Bridge. Authorities said they were working to help ensure that the remaining product in the ship was safely secured in order to begin reopening the ship channel.

Following the incident there were public warnings about fumes from the chemical, which can be dangerous if inhaled in high doses, causing dizziness and suffocation. Air quality monitoring throughout the area confirmed that fumes were present, but showed they were below toxic levels.

A narrow sheen about two miles long has been seen in the water as a result of the incident, but water monitoring has also shown no public health concern at this time, according to the Central Texas Coastal Area Committee (CTCAC).

On Tuesday evening CTCAC reported that one of the two vessels, the Conti Peridot, was being moved to the Port of Houston Authority's Turning Basin terminal.

The cause of the collision is still under investigation.