Mercury Analysis

Adelana Adesuyi

Faculty Advisor: Jennifer Look, Ph. D.

Mercer University, Macon, GA

Introduction

Types of Mercury

There are two main, dangerous types of mercury that are particularly relevant to the Neighborhood Chemistry Research Team’s study. These two forms are methylmercury and elemental mercury. Methylmercury is a form of mercury that is particularly harmful and can accumulate in fish populations, whereas elemental mercury is contained in light bulbs and older models of thermometers. If these common household items are broken and not properly disposed of in a safe and timely matter, several negative health effects can occur. The proper disposal techniques of broken light bulbs and thermometers will be discussed later in the article.

Dangers of Mercury

Power plants tend to emit largest amounts of mercury on a regular basis, according to the Environmental Protection Agency (EPA). When discussing the large amounts of mercury emissions released by major power plants, it is also necessary to understand the dangers and effects of this mercury on the surrounding area and population. Many power plants tend to dump their remaining waste into neighboring bodies of water. This results in fish acquiring growing amounts of methylmercury within them. After that, people tend to consume fish, along with the mercury already located in the fish. This is a process called biomagnification. When a person consumes several fish with mercury detected in it, the person begins to accumulate the mercury levels within their body. This is particularly hazardous as every year, more than 300,000 newborns children are born with an increased risk of learning disabilities and developmental complications from in utero mercury exposure. This is because mercury is a neurotoxin than can impair neurological developments in newborns and young children. According to the EPA, over “200,000 children may be born in Georgia with dangerously high levels of mercury in their blood.” This has resulted in issuances of warnings regarding toxic levels of mercury contained in the fish that people consume.

In household objects, similar dangers occur from breaking elemental mercury-based thermometers, compact fluorescent light bulbs (CFL), and ritualistic and religious objects that contain mercury. The main demographic that is most easily affected by mercury (Hg) exposure is young children. This is due to three main reasons. The first is that Hg vapors tend to settle lower in the air, around the height where many young children play. This means that young kids have an increased amount of exposure to Hg. Second, children are less capable of keeping mercury out of the brain due to their age and lack of development. Therefore, the Hg that they intake, tends to make its way to the brain and stay

there. Lastly, children tend to have higher respiration rates than adults. Thus, they have more opportunities to breathe in Hg vapors. Despite all this, everybody can be negatively affected by Hg exposure; young children tend to receive the effects sooner. Some of the main effects of Hg exposure include kidney and nervous system damage. When the nervous system is affected by Hg, it can result in a decrease of motor skills, poor concentration, tremors, difficulty walking, trouble sleeping, decrease of nerve impulse conduction, potentially permanent short-term memory loss along with many other health effects. The most serious effect of mercury exposure is death, which only occurs if a large amount of mercury has been built up within one’s body. As a result, the EPA has set a standard safety limit for how much mercury can be safely breathed in as 300 nanograms per cubic meter (ng/m 3 ). Any value below this level is not deemed as critically dangerous for breathing.

Mercury in the Air

Major Sources of Mercury in the Air

According to the EPA, in the United States, power plants are responsible for more than 50% of all domestic human-produced emissions of mercury. These power plants oftentimes dump their waste into neighboring bodies of water, which causes reservoirs and lakes to exceed the safety limit proposed by the EPA. Data from the EPA also reveals that there has been in an increase in mercury emissions from 2007 to 2008. Additionally, from the year 2000 to 2008, there were approximately 417.1 tons of mercury (Hg) emissions in the United States. This data was self-reported by the power plants themselves, which may indicate that the amount of emissions may be much higher than each plant actually reported.

The state of Georgia has two of the top 50 dirtiest power plants in the nation. One of the two is the Scherer Power Plant. Taking into consideration the large amount of mercury emissions that power plants produce, it was expected that the local Plant Scherer, rated third dirtiest power plant in 2008, would report high levels of mercury during testing. There has also been an increase in Hg emissions compared to the year 2000, which further led the Research Team to expect higher mercury levels. On the other hand, several new regulations regarding mercury emissions at Georgia power plants have been implemented in the past few years. These regulations resulted in adjustments being made to the plant in 2009 and 2010. As a result of these new pollution regulations, Plant Scherer has decreased its mercury output from its previously 1,589 pounds in 2008 to only 221 pounds of mercury in 2011. This new number shows a drastic change of 1,368 pounds less of mercury emissions during a three-year span. Additionally displaying the progress of the plant, Scherer was no longer a member of the top ten list (provided by the same organization that placed them at third previously) of the largest mercury emitting power plants in 2013. After considering these new advancements that were made, the Research Team then expected lower levels of mercury to be found in the data than there would be if testing were done in the earlier 2000s.

Testing for Mercury in Macon’s Air

To measure the amount of elemental mercury in the air at several locations (pictured below), the Team used a device called the RA-915M Mercury Lumex (also show below). This device is a high precision device that is used to measure the concentration of mercury vapor in ambient air. The Lumex can also be used to detect amounts of mercury in liquids, solids, and gases. The Lumex device works based on absorption spectrometry, which is a method used to detect the concentrations or amount of an element in a sample. The concentration is measured in nanograms per cubic meter (ng/m3). According to the EPA, the safety limit for daily outdoor inhalation is 300 ng/m 3 . In other words, if the amount of mercury measured in ng/m3 is above 300, then the people located in those regions are inhaling dangerous amounts of mercury that can cause serious health complications. Additionally, because power plants release the largest amount of mercury into the air, they hold a lot of responsibility when it comes to the effect of mercury pollution on people.

Results of Testing- Macon and Bibb County Air

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Above: An image of the RA-915M Mercury Lumex used for testing.

The data results, found from testing various locations around Macon and Bibb County, reveal that Macon does not have dangerous levels of mercury in the air, and it is well below the safety limit (each of the values is between 1.5 and 4 ng/m3). Additionally, the low standard deviation of our data reveals that the results that we obtained are consistent with one another, thus they are reliable. We decided to test at these locations as Plant Scherer is located nearby each of the selected sites. We wanted to see if the close proximity of the power plant caused a significant amount of mercury air pollution. This is because Plant Scherer is a coal-driven power plant, and coal releases a significant amount of air pollution. This particular plant is also particularly known for its large amount of air pollution as it is referred to as the nation’s largest emitter of greenhouse gases as well as the “dirtiest power plant in the nation.” However, as we can see from the data, the power plant has not had a major impact on increasing the mercury air levels, as the levels are safe for daily inhalation (below 300 ng/m3).

Mercury in Household Items: Compact Fluorescent Light Bulbs

Note: When mercury is not properly disposed of and cleaned up, mercury vapor may begin to build up within the location, causing serious health conditions. Instructions for cleaning household mercury spills are recommended by the EPA can be found here.

Introduction

The Compact Fluorescent light bulb (CFL) has become one the main types of light bulbs used in the nation as Incandescent light bulbs have become phased out. CFLs have been used to replace the incandescent light bulb, as it requires less electricity to generate light and are more energy efficient. However, CFLs tend to have hazardous elemental mercury contained within them, but only around 3-5 milligrams (mg) of mercury (It is important to note that no mercury is released from the bulb as long as it is intact). This amount is typically not dangerous enough to cause severe danger if a CFL bulb is broken from time to time. A 2011 study revealed that only a minute fragment of hazardous mercury is actually released when a CFL is broken. However, if the mercury is not properly cleaned up after the CFL breaks, the amount of dangerous mercury vapor can begin to build up and begin having adverse health effects on those who live in the location.

Testing of Compact Fluorescent Light Bulbs

Two separate tests were conducted regarding CFLs. The first test was designed to compare the Hg concentration levels of two different manufacturing brands, EcoSmart (which is intended to be more

Above: This graph shows the atmospheric mercury concentration at each of the sites tested throughout Macon and Bibb County. The purple dotted line

represents the EPA's determined safe daily limit for mercury inhalation as 300 ng/m 3 , and each of the determined values are well below the safety limit. See

map or click here for location of sites.

environmentally friendly than most light bulbs) and Philips (which represents the more standard CFL). The second test was conducted to test the EPA’s recommended cleaning procedure (found here) for released Hg from a broken CFL. To test the two brands of CFL and the EPA clean up procedure, the Research Team used the Mercury Lumex device previously used to test levels of Hg in Macon’s air. The results of the testing are found below.

Results of Testing-Compact Fluorescent Light Bulb Brands

To conduct the test, each of the light bulbs from each brand was placed into a closed jar without any additional means of sealing besides tightening the lid. The data results reveal that the more “environmentally friendly” light bulb (EcoSmart) has significantly lower levels of mercury detected by the Lumex than the Philips light bulb does. The varying values of the bar graph indicate varying readings by the Lumex, as the amount of mercury emitted may fluctuate over time. However, the general trend reveals that the EcoSmart CFL has consistently lower levels of mercury emissions. It is also important to note that, when broken, both brands have Hg levels well below the 300 ng/m3 EPA limit.

Results of Testing-Environmental Protection Agency Recommended Clean Up Procedure

To test EPA’s recommended clean up procedure, the Research Team placed a broken CFL into a jar, following the instructions set by the EPA. The instructions can be found here. The mercury readings

Above: Hg concentrations of both the Philips and EcoSmart brand CFl as read by the Mercury Lumex device. Results show that the EcoSmart brand has lower levels of Hg than the standard Philips CFL.

were taken at varying distances of 1.5 inches, 6 inches, 12 inches, 36 inches, and 72 inches in order to simulate at-home interactions with broken mercury and the dangers that correspond with it. The first trial yielded the results as follows in the graph below.

The data shows that at one and half inches from the sealed jar, the mercury readings were as high as almost 4,000 ng/m3, which is well above the 300 ng/m3 safety limit. However, at around six inches from the jar, the reading dropped drastically to a value between 500 and 1,000, which is still above the safety limit. It only reached a value below the safety limit at a distance of twelve inches and

Above: This graph represents the mercury concentrations taken at each distance from the closed jar containing a broken fluorescent light. It demonstrates that merely closing the object in a jar is not enough to keep mercury levels at a safe level.

more. The significance of the data reveals that merely following the EPA’s procedure is not enough to maintain the Hg concentration at a safe level of less than 300 ng/m3.

After this initial trial, the test was repeated with the addition of electrical tape as an additional means of sealing the jar. The results of this test coincided with the initial testing of the room. This means that the mercury emission level decreased drastically with the addition of the electrical tape as a

sealant. Therefore, the electrical tape is a safer method, in addition to the already sealed jar, for disposing of and containing mercury from broken light bulbs. The readings also revealed that the concentrations were below the safety limit. Thus, it is recommended to follow the suggested EPA clean up procedure along with electrical tape as an added safety feature. A photo of the sealed CFL with the electrical tape used to seal the jar is below.

Mercury in Household Items: Thermometers

Introduction

Just as CFL bulbs contain mercury, the more traditional (and now more outdated) type of thermometers is the mercury thermometer. In this type of thermometer, the section that is commonly red holds the mercury. However, in mercury thermometers, the mercury is a silver color, not red. From this coloring, it is usually easy to determine if a thermometer is mercury-based or alcohol, as alcohol based thermometers are colors other than silver (red, blue, purple, etc.). On the other hand, if a thermometer is broken, it is recommended that the thermometer be treated as though it contains mercury, for safety reasons. Common household thermometers that contain mercury are fever, oven, candy, and meat thermometers. The Research Team conducted a test identical to the broken CFL test by following the recommended EPA procedure with and without the additional electrical tape for further sealing. The results can be seen below.

Above: An image of the sealed light bulb with electrical tape used as an added step yielding lower levels of released mercury emissions.

Results of Testing-Thermometer

Jar sealed with EPA recommended instructions

EPA safety limit- 300ng/m3

Above: Results of Hg readings of following EPA recommended clean up of a broken thermometer sealed in a jar compared to sealing with electrical tape. Results reveal

that electrical tape reduces exposure to below the EPA safety limit.

The results of testing reveal that sealing the jar with the broken thermometer keeps the level of Hg below the 300 ng/m3 safety limit. On the other hand, without the additional electrical tape, the Mercury Lumex readings indicate levels well above the safety limit, such as at 2,000 ng/m3, similar to CFL testing.

Ritualistic and Religious Items

Introduction

In the world today, there are many religious and ritualistic practices involving mercury. These practices are most often deemed as unsafe. Some religious purposes for using mercury include bringing love, luck, and fortune, protection from evil, and spiritual cleansing, while some ritualistic practices include consuming mercury-filled pills to heal physical ailments, placing mercury under the bed night, rubbing a mercury and alcohol combination on areas of skin with arthritis, evaporating mercury by candle, etc. Many of the practices involving mercury tend to cause further issues rather than solving the initial problem. However, each of these practices tends to pose health threats.

The Research Team decided to conduct a test measuring the Hg concentrations from five different religious objects using the Mercury Lumex. Each object was sealed in a jar (as in previous tests without the electrical tape) along with a segment of carpet for 20 minutes then with a piece of tile for 20 minutes. This was done to replicate the absorption levels of mercury onto the floor of a home where mercury objects are used. The read values would indicate how much exposure a resident would be exposed to over time. The readings were taken every minute and graphed below.

Results of Testing of Ritualistic and Religious Items

The mercury object and the surface (carpet/tile) are placed in a fixed-volume container with the end of the Lumex hose running through the top hole of the container. For this set up, the container used is a Styrofoam cooler. An image of the experimental set up is depicted below.

The results of the testing reveal that the carpet surface absorbs higher Hg concentrations than the tile surface. However, both of the surfaces retain unsafe levels of Hg for the first several minutes as they both reach at least 2,000 ng/m3 , which is well above the 300 ng/m3 safety limit. These values represent what a ritualistic or religious user may be regularly exposed to when they exercise their particular practices involving mercury.

Above: Results of the surface and mercury object testing showing that carpet has higher amounts of Hg absorbed than tile.

Above: Experimental setup used in testing the mercury objects and