Common Causes Of Mercury Contamination

Mercury is a heavy metal that is a liquid at room temperature. Generally, it is safe in this form, though it can cause skin irritation in sensitive individuals. Mercury is toxic when it is inhaled as a vapor. In this form, it enters the bloodstream through the lungs and is then stored in fatty tissue in the body. As the level of mercury increases, there will be signs of mercury contamination. Early warning signs are headaches and general fatigue. As the level continues to increase, more serious neurological symptoms develop including tremors, memory loss, and slow reaction time. High levels of mercury can also cause damage to the kidneys.

Silver Dental Fillings

Silver dental fillings are one of the most common ways in which individuals are exposed to mercury. These fillings have been used for decades as the main treatment for cavities in children and adults. The decayed area is drilled and then filled with silver dental amalgam. This substance can be forty to fifty percent mercury mixed with silver, tin, and copper. Over time, these fillings will release a small amount of mercury vapor into the bloodstream. In most cases, the amount of mercury is negligible. In the United States, both the Food and Drug Administration and the Centers for Disease Control have found silver dental amalgam to be safe for adults and children over six years old. In a small number of cases, individuals with a genetic predisposition to mercury toxicity can have a reaction to the mercury in these fillings.

Overconsumption Of Seafood

The biggest source of mercury contamination is found in the consumption of seafood. There is some concern the overconsumption of seafood can expose individuals to toxic levels of the metal. However, most medical professionals believe the heart benefits of the omega-3 fatty acids found in seafood outweigh the risk of mercury exposure. There are guidelines recommended for pregnant or nursing women and small children to avoid mercury contamination. For these groups, seafood consumption should be limited to two six-ounce portions per week. The highest levels of mercury are found in larger fish, especially those in the Gulf of Mexico. Shark, king mackerel, and swordfish from this region should be avoided. Instead, at-risk populations should stick to seafood with lower mercury levels such as shrimp, salmon, and pollock.

Broken Thermometers

Broken thermometers can expose individuals to liquid mercury, as older thermometers use the metal to measure temperature. The glass bulb at the bottom of the thermometer is filled with mercury. As the temperature increases, the metal expands into the graded tube. Since these thermometers are made of glass, a hard impact can break the tube, spilling mercury onto nearby surfaces. While touching mercury is not recommended, it is not toxic to the touch. In order to pick up as much mercury is possible, it is best to sweep it onto a dustpan with a squeegee. Dabbing the area with duct tape can pick up small particles of the metal as well. It is important to remove as much of the mercury as possible as it will slowly vaporize at room temperature, releasing toxic mercury vapor.

Exposure To Certain Pieces Of Jewelry

Exposure to certain pieces of jewelry can also lead to a liquid mercury spill. The jewelry in question is commonly manufactured in Mexico. It is normally a necklace with a glass pendant filled with mercury. Sometimes coloring is added to the bulb to give the piece a unique look. The liquid metal flows in its container as it swings back and forth. However, like glass thermometers, these pendants can break on impact, spilling liquid mercury. Although it is a liquid, mercury should never be poured down a drain as it can contaminate waterways downstream. Once the metal is properly cleaned from surfaces, it should be taken to the closest hazardous waste collection center for responsible disposal.

Contact With Older Paints

For many years, mercury was added to indoor, water-based latex paints as an effective way to control the growth of bacteria and prevent mildew. For this reason, contact with older paints can lead to mercury contamination. While in the United States this practice was banned in 1990, individuals may still have these paints sitting in their garages or basements. The greatest concern is after the initial application when the highest amount of mercury vapor is produced. If homeowners find old cans of this paint, it is important to dispose of them properly. They should not pour the paint out of cans and down a drain. Instead, they should bring the paint to a hazardous waste disposal center.