Gulf of Mexico - Pollution

Pollution

The major environmental threats to the Gulf are agricultural runoff and oil drilling.

There are frequent "red tide" algae blooms that kill fish and marine mammals and cause respiratory problems in humans and some domestic animals when the blooms reach close to shore. This has especially been plaguing the southwest and southern Florida coast, from the Florida Keys to north of Pasco County, Florida.

The Gulf contains a hypoxic dead zone that runs east-west along the Texas-Louisiana coastline. In July 2008, researchers reported that between 1985 and 2008, the area roughly doubled in size and now stretches from near Galveston, Texas, to near Venice, Louisiana. It is now about 8,000 square miles (21,000 km2), nearly the record. Poor agricultural practices in the northern portion of the Gulf of Mexico have led to a tremendous increase of nitrogen and phosphorus in neighboring marine ecosystems, which has resulted in algae blooms and a lack of available oxygen. Occurrences of masculinization and estrogen suppression were observed as a result. An October 2007 study of the Atlantic croaker found a disproportioned sex ratio of 61% males to 39% females in hypoxic Gulf sites. This was compared with a 52% to 48% male-female ratio found in reference sites, showing an impairment of reproductive output for fish populations inhabiting hypoxic coastal zones.

There are 27,000 abandoned oil and gas wells beneath the Gulf. These have generally not been checked for potential environmental problems.