Exposure assessment of a mercury spill in a Nevada school -- 2004

Case series of mercury toxicity among children in a hot, closed environment

Mercury poisoning is much more prevalent in the general population than possibly many physicians realize. We present data on 26 pediatric cases with mercury intoxication from exposure to mercury by inhalation or skin contact as a result of a broken thermometer in a school laboratory. This is the largest pediatric series in Turkey. During a 3-month period, the study team observed the children for clinical symptoms, physical findings, and blood and mercury levels. Of all patients, 21 inhaled, 3 inhaled and touched the element, and 2 took the mercury home. Sixteen children were symptomatic at admission, although blood mercury levels in the symptomatic children were higher than those in asymptomatic children (P = 0.003). The urine mercury levels were not statistically different between the groups at the admission (P > 0.05). The exposure times were 3.5 and 2 hours for symptomatic and asymptomatic children, respectively (P = 0.003). The 2 children who took the mercury home had the highest blood mercury levels and the most prolonged exposure time. N-acetylcysteine and chelation treatments were started in 21 children who had symptoms of mercury intoxication and high mercury levels in their blood or urine. No adverse effects were observed during chelation therapy. Prompt removal of children from contaminated environments and proper decontamination or elimination of devices containing large amounts of mercury from schools are necessary to prevent serious complications caused by exposure to mercury.

Household poisoning cases from mercury brought from school

Mercury has a number of unique and fascinating properties. It is present in the environment in several forms, both organic and inorganic. Each of these forms has somewhat unique properties that differentiate them from the other forms, but all are toxic to humans in one way or the others. Mercury has been proven to be a potential source of poisoning in children as a result of the inappropriate handling of a liquid mercury. The cases of metallic mercury vapor intoxication not associated with occupational exposure may occur in school science laboratories, from mercury dust and powders, from latex paint containing a mercury-based fungicide, and from normal wear or installation of dental amalgam fillings. Another source of toxic mercury exposure can be broken thermometers, barometers, or sphygmomanometers that may occur in the home, and children are often victims of environmental exposure. In this paper, we present three members of a family who were exposed to mercury brought home from school by a family member. Since the mercury exposure was not known, the initial presentation and clinical picture suggested a misdiagnosis, a contagious infectious disease, because the onset of symptoms occurred at different times in the same family members. A subsequent change to a diagnosis of mercury intoxication and chelation therapy with meso-2,3-dimercaptosuccinic acid was started.

Mercury exposure and children's health

Acute or chronic mercury exposure can cause adverse effects during any period of development. Mercury is a highly toxic element; there is no known safe level of exposure. Ideally, neither children nor adults should have any mercury in their bodies because it provides no physiological benefit. Prenatal and postnatal mercury exposures occur frequently in many different ways. Pediatricians, nurses, and other health care providers should understand the scope of mercury exposures and health problems among children and be prepared to handle mercury exposures in medical practice. Prevention is the key to reducing mercury poisoning. Mercury exists in different chemical forms: elemental (or metallic), inorganic, and organic (methylmercury and ethyl mercury). Mercury exposure can cause acute and chronic intoxication at low levels of exposure. Mercury is neuro-, nephro-, and immunotoxic. The development of the child in utero and early in life is at particular risk. Mercury is ubiquitous and persistent. Mercury is a global pollutant, bio-accumulating, mainly through the aquatic food chain, resulting in a serious health hazard for children. This article provides an extensive review of mercury exposure and children's health.

A review of events that expose children to elemental mercury in the United States

Concern for children exposed to elemental mercury prompted the Agency for Toxic Substances and Disease Registry and the Centers for Disease Control and Prevention to review the sources of elemental mercury exposures in children, describe the location and proportion of children affected, and make recommendations on how to prevent these exposures. In this review, we excluded mercury exposures from coal-burning facilities, dental amalgams, fish consumption, medical waste incinerators, or thimerosal-containing vaccines. We reviewed federal, state, and regional programs with data on mercury releases along with published reports of children exposed to elemental mercury in the United States. We selected all mercury-related events that were documented to expose (or potentially expose) children. Primary exposure locations were at home, at school, and at others such as industrial property not adequately remediated or medical facilities. Exposure to small spills from broken thermometers was the most common scenario; however, reports of such exposures are declining. The information reviewed suggests that most releases do not lead to demonstrable harm if the exposure period is short and the mercury is properly cleaned up. Primary prevention should include health education and policy initiatives.

A review of events that expose children to elemental mercury in the United States

OBJECTIVE

Concern for children exposed to elemental mercury prompted the Agency for Toxic Substances and Disease Registry and the Centers for Disease Control and Prevention to review the sources of elemental mercury exposures in children, describe the location and proportion of children affected, and make recommendations on how to prevent these exposures. In this review, we excluded mercury exposures from coal-burning facilities, dental amalgams, fish consumption, medical waste incinerators, or thimerosal-containing vaccines.

DATA SOURCES

We reviewed federal, state, and regional programs with information on mercury releases along with published reports of children exposed to elemental mercury in the United States. We selected all mercury-related events that were documented to expose (or potentially expose) children. We then explored event characteristics (i.e., the exposure source, location).

DATA SYNTHESIS

Primary exposure locations were at home, at school, and at other locations such as industrial property not adequately remediated or medical facilities. Exposure to small spills from broken thermometers was the most common scenario; however, reports of such exposures are declining.

DISCUSSION AND CONCLUSIONS

Childhood exposures to elemental mercury often result from inappropriate handling or cleanup of spilled mercury. The information reviewed suggests that most releases do not lead to demonstrable harm if the exposure period is short and the mercury is properly cleaned up.

RECOMMENDATIONS

Primary prevention should include health education and policy initiatives. For larger spills, better coordination among existing surveillance systems would assist in understanding the risk factors and in developing effective prevention efforts.