A 19-year-old man has been arrested after trace amounts of mercury spilled at three locations in Houston, leading dozens of people to be decontaminated as a precaution, FBI said Monday.
The agency's Houston office said on Twitter that Christopher Lee Melder has been charged with burglary and unlawful disposal of hazardous material. The FBI announced early Monday that he was taken into custody for questioning in connection with the spill. He is also charged on an outstanding felony drug possession warrant.
It wasn't immediately known whether he had a lawyer and authorities didn't immediately say why the mercury was spilled.
Houston Fire Chief Sam Pena said at a news conference Sunday evening that the situation was under control and crews were cleaning up the spills. There's no timetable for when the cleanup will be complete.
Someone called 911 around 11:15 a.m. Sunday to report a white liquid on the ground, Pena said. Officials later determined that mercury was spilled outside a Walmart, a Sonic Drive-In and a nearby gas station. All three locations were evacuated and between 30 and 60 people were asked to take decontamination showers as a precaution, Pena said.
The fire chief added that one woman was taken to a hospital as a precaution because she was pregnant.
Police said it's unclear how or when the toxic metal was spilled. Federal and local investigators were trying to determine whether it was intentional.
Authorities also said they're looking into reports that someone checked into a hospital Friday in Harris County, where Houston is located, claiming to have been exposed to mercury.
According to the Centers for Disease Control and Prevention, mercury exists in three forms. Elemental mercury is liquid at room temperature. It is used in some thermometers, fluorescent light bulbs and electrical switches. High mercury vapor concentrations can cause severe lung damage, the CDC said.
Dr. David Persse with the Houston Health Department said that because all three spills happened outdoors, the risk to people in the area is minimal.
WHAT IS MERCURY? Mercury is a heavy, silvery liquid that occurs naturally in the earth's crust, and is released into the air, water and soil in several forms. It's used in such things as thermometers, batteries. fluorescent light bulbs and dental fillings, though its use has diminished because of concerns about its toxicity. Sources of mercury in the environment include the burning of coal and mining activities.
WHAT ARE THE POTENTIAL HEALTH EFFECTS? Mercury is a potent neurotoxin, but health effects depend on how much mercury you're exposed to, how long you're exposed and your age. Small children are most vulnerable.
Liquid mercury can change into a gas. Short-term exposure to metallic mercury vapors -- such as from spills -- can cause lung damage, nausea, vomiting, diarrhea, increased blood pressure and heart rate, skin rashes, and eye irritation. Exposure to high levels can permanently damage the brain, kidneys and developing fetuses.
Bacteria in water and soil can transform mercury into another form, called methylmercury, which builds up in the food chain. Most people are exposed by eating fish contaminated with mercury.
There are blood and urine tests that can measure mercury levels in a person's body.
WHAT IF I SPILL MERCURY? Emergency officials should be called for any spill greater than the amount found in a thermometer, thermostat or light bulb. A hazardous materials team was called last week to clean up a half cup of mercury found on the basement floor at a water treatment plant in Oswego, New York.
If a small item such as a thermometer or compact fluorescent light bulb breaks, the Centers for Disease Control and prevention says it can be cleaned up by following specific instructions. Any clothing that comes in contact with the liquid should be thrown away. Mercury should not be washed down the drain.
In all cases, all outside windows and doors should be opened, and people and pets should leave without walking through the spill.