FROM THE BENCH
Mercury Surveillance : A Collaborative Effort to Help a Family
By Jocelyn Hover-Jeansonne , MPH , CT coordinator , Texas Department of State Health Services – Central Campus
Early one evening in mid-November 2021 , the Texas Department of State Health Services ( DSHS ) Chemical Threat ( CT ) Response Laboratory in Austin received an inquiry about capabilities to analyze biological specimens for mercury levels . It was suspected that multiple linked families had been exposed to significant amounts of elemental mercury , but their exposure had gone undiagnosed for many months . The primary exposure took place in Missouri during July 2021 and would move within the borders of the Lone Star State in August 2021 . The causative agent would not be identified for several months , and the source material would not be recovered . Three children would continue to experience symptoms , including a 2-year-old in Texas , leading to many medical clinic visits , trips to the emergency room department , hospitalization , laboratory testing and a variety of diagnoses prior to heavy metal exposures being considered . A breakthrough would come when exposure to elemental mercury was confirmed by treating physicians in Missouri after two adolescents had been hospitalized . This information soon was brought to the attention of treating physicians in Dallas where the youngest exposed was in the hospital . Mercury is a liquid element that is easily vaporized and inhaled at room temperature . Exposure to mercury , even small amounts , may cause serious health problems and impact the nervous , digestive , and immune systems , lungs , kidneys , eyes and skin .
Journey to Diagnosis
Symptoms in the family members started to appear as early as July 2021 in the form of rashes ; however , the rashes were not linked to mercury . Two of the adolescents in Missouri developed high persistent pain and weakened immune systems leading to hospitalization . From July through November , the youngest child of the Texas family presented with fever , cough , rash , anorexia , abnormal white blood cell counts , conjunctivitis and ear pain . Testing for respiratory syncytial virus ( RSV ), COVID-19 , influenza and streptococcal pharyngitis , along with other viruses and bacteria typically tested for on hospital respiratory panels , were repeatedly negative . Prior to July 2021 , the 2-year-old female had no significant medical history . On October 31 , 2021 , after many out- and in-patient assessments , referrals to pulmonary and rheumatology specialists , the parents informed treating physicians of extended family members who were being treated for confirmed mercury toxicity . Two urine samples were collected and sent for commercial laboratory testing for mercury . Empiric treatment for mercury toxicity was initiated prior to receiving the laboratory results due to the long turnaround times . The advantage of sending these samples to the DSHS CT Laboratory in Austin would be expedited testing with results available within 24 hours of sample receipt , thus providing the treating physicians tangible information for treatment decisions . The commercial laboratory was also only able to report “ greater than 80 mcg / L ” for these samples . Through the DSHS CT Laboratory , a greater analytical measurement range ( AMR ) for mercury in biological specimens is available allowing for more significant measurements of the mercury bio-burden for potentially exposed individuals .
Collaboration
The Agency for Toxic Substances and Disease Registry ( ATSDR ) Region 6 notified the DSHS Health Assessment and Toxicology ( HAT ) program of the potential mercury exposure of the Texas family and thus began a collaboration — facilitated by DSHS HAT — involving the exposed family , the Texas Commission on Environmental Quality ( TCEQ ) Amarillo Regional Office , the DSHS Public Health Region ( PHR ) 9 / 10 and the DSHS CT Laboratory to help the
Mercury exposure rash in 2-year-old female . Photo : TX DSHS
family of five children , two adults and two canines .
Decontamination
Mercury testing of the homes revealed hazardous mercury vapors as high as 3 mcg / m 3 ( Texas ) and 40 mcg / m 3 ( Missouri ). The Texas family relocated until remediation was complete . TCEQ removed mercury-contaminated household items and ventilated the home . The remediation was completed and TCEQ cleared the home when mercury concentrations were < 0.5 mcg / m 3 . Residential mercury contamination was below those expected to cause immediate health concerns , but were still higher than the ATSDR ’ s action level ( 0.001 mg / m 3 ) for long-term exposure . Therefore , DSHS HAT worked with DSHS Region 9 / 10 staff and DSHS CT Laboratory to conduct biosurveillance of the exposed family members and pets until their mercury levels returned within normal / reference range .
Biosurveillance & Laboratory Testing
The DSHS CT Laboratory prepared and analyzed a total of 78 urine samples and 21 blood samples for mercury testing . These samples were prepared and
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