Texas Business reports: The Texas Department of State Health Services issued an advisory warning people not to consume blue marlin caught in all waters off the Texas coast due to unsafe levels of mercury.

Mercury is a naturally occurring element that can also be a byproduct of human activity. If consumed regularly, it can cause harmful effects to the central nervous system, particularly in children including infants exposed before birth. Symptoms of prolonged exposure include tingling of the skin, loss of coordination, visual and hearing impairment and slurred speech.

Additionally, women of childbearing age, including women who are nursing, and children under 12 years old should not consume swordfish caught off the Texas coast. The advisory recommends women past childbearing age and adult men limit their consumption of swordfish from this area to no more than two meals per month.

The advisory was issued after testing revealed that blue marlin and swordfish examined from the northwestern Gulf of Mexico contained mercury at concentrations that exceed DSHS health guidelines of no more than 0.7 mg/kg. The average levels found in blue marlin were 12.9 mg/kg, more than 18 times the DSHS guidelines. The levels in swordfish, 1.18 mg/kg, were more than 1.6 times the recommended levels. Regular or long-term consumption of blue marlin and swordfish from these waters may result in adverse health effects.

While most recreational fishermen catch and release blue marlin and swordfish in the Gulf of Mexico, some fish is kept for personal consumption. Because of the large minimum catch size, any legally caught blue marlin will have high levels of mercury. With increased recreational swordfish catches, anglers are eating more and larger swordfish that can have elevated mercury levels.

Note: An advisory for the Texas Gulf Coast is already in place recommending that king mackerel greater than 43 inches total length not be consumed; for king mackerel 37 to 43 inches total length, women of child bearing age and children less than 12 years of age should consume no more than one meal per month, and women past childbearing age and adult men should consume no more than one meal per week; and king mackerel less than 37 inches total length are safe for unrestricted consumption.  A meal is 8 ounces of fish.