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New Information Limiting Mercury Hazards From Rubber Like Floors

Limiting Mercury Hazards from Rubber-Like Floors

We don't usually re-send ADVISOR articles, but reports of elevated mercury in gym floors in NJ schools have recently been in the news.  For example, a new NJ.Com article about the Washington Township School District in Gloucester County which found elevated mercury in 8 out of 11 gym floors tested. These important findings highlight the need to conduct testing for mercury as soon as possible to determine if the risk of mercury exposure exists in your schools.
Please read on for additional information about mercury hazards.

The NJ School Boards Association distributed a report titled, Health and Safety Guide:  Mercury Hazard in Schools from Rubber-Like Polyurethane Floors, which was prepared by the NJ Education Association and the NJ Work Environment Council. The NJ Department of Health, Division of Epidemiology and Environmental and Occupational Health has also issued a Fact Sheet titled, Guidance of NJ Schools: Evaluating Mercury in Synthetic Flooring.

The reports are designed to alert school officials to a potential health risk associated with exposure to metallic mercury vapors from rubber-like polyurethane floors. These floors, which have been in use since the 1960's, may be found in school multi-purpose rooms, gyms, cafeterias, auditoriums, stages and indoor and outdoor tracks. Suspect floors are synthetic polyurethane, not wood or vinyl tile.  They are resilient and rubber-like, water resistant, and may be tinted any color. They may be one piece, sometimes pieced or poured in place.

Some of this flooring material has been shown to contain a mercury containing chemical, PMA, which under certain conditions may emit colorless and odorless metallic mercury vapors into the air. 

Mercury may affect you when inhaled and may be absorbed through the skin. Symptoms of exposure include:

-          Irritation of the eyes, skin nose, throat and lungs
-          Metallic taste in the mouth
-          Nausea and vomiting
-          Abdominal pain
-          Mercury poisoning, with tremors
-          Personality changes
-          Trouble remembering and concentrating
-          Gum problems
-          Kidney damage

Mercury exposures may be worse if the floors are damaged or have deteriorated, or are located in hot rooms with poor ventilation. Exposure to mercury vapors may be a serious health hazard to both students and school employees, such as custodians who clean this flooring material.  Some floors have been shown to contain enough mercury to create significant airborne exposures and require disposal as hazardous waste.

Fortunately, there is an easy way to find out if this is an issue in your school.  Garden State Environmental, Inc. (GSE) recommends collecting and submitting small representative (full-thickness) pieces of the flooring (bulk samples) to an accredited laboratory for mercury analysis.  If the mercury content is less than one (1) Part Per Million (PPM) there should be no concerns about mercury exposure. However, if mercury levels exceed 1 PPM, additional follow-up work is indicated, including possible full day air sampling, which is recommended to determine if a mercury exposure issue exists. Such testing must be done by a qualified and experienced Industrial Hygienist to ensure that the proper methodologies are used and the results are interpreted in accordance with the most protective exposure levels.  This can be tricky since there are a number of differing exposure guidelines published from governmental and advisory agencies including the NJDOH, OSHA, ACGIH, TSDR and USEPA.  

There are no good estimates about the number of these floors that are currently installed in school buildings, or if they are still being installed, and many NJ school districts may not be aware of this potential hazard.  The school should inspect each school facility to identify any "rubber-like" flooring that may be present. They should note the location, square footage and overall condition of such flooring. 
Once the initial survey is completed, GSE can help design and conduct a simple and inexpensive bulk sampling strategy to determine if mercury exposure from this flooring is a concern. If necessary, we can also develop and implement an air sampling program in accordance with published methods to further delineate possible exposures and guide the District in appropriate protective actions. 
GSE recently conducted mercury sampling at a local NJ public school.  The school had rubber-like synthetic flooring in the gym and was concerned about the possibility that the floor contained mercury and could pose a risk to students and employees.  GSE conducted bulk sampling, and determined that the flooring did indeed contain mercury at levels above 1 PPM, the level that indicates additional follow-up work is needed.  GSE mobilized immediately to conduct air sampling to determine if the mercury vapors were being emitted into the air and if a hazard existed.  We found that while there were measurable airborne mercury exposures, they were below the most current guidelines established by the NJ Department of Health.  GSE is working with the District to make sure the room is properly ventilated and will be conducting additional air sampling to verify that the levels of exposure remain safe, until such time as the district replaces the flooring material.
                NJ School Boards Association
                NJEA Mercury Information

                NJEC Fact sheet