Epidemiology, clinical presentation, treatment, and follow-up of chronic mercury poisoning in China: a retrospective analysis.

BACKGROUND: There are no reports on the incidence of chronic mercury poisoning in a large population in China. This study investigated the epidemiology, clinical manifestations, treatment, and follow-up of Chinese patients with chronic mercury poisoning. METHODS: Data for 288 mercury poisoning patients were collected at our hospital from July 2014 to September 2019, including sex, age, admission time, blood mercury content, urine mercury content, creatinine, urinary mercury/creatinine ratio, 24-h urinary protein levels, electromyography (EMG) findings, renal biopsy, and follow-up. Patient characteristics were evaluated by statistical and correlation analyses. RESULTS: First, mercury poisoning in China mainly occurred through occupational exposure and the inappropriate use of mercury-containing cosmetics and Chinese folk remedies (CFRs). Second, the most common symptoms were nervous system (50.3 %), kidney (16.4 %) and breathing (8.0 %). Mercury poisoning-induced Nephrotic syndrome (NS) and peripheral neuropathy are common long-term complications. The complications of occupational and cosmetics-induced mercury poisoning are consistent with international belief. However, the NS caused by CFRs is mainly membranous nephropathy and the probability of peripheral neuropathy caused by CFRs is higher than other pathogens. Third, follow-up data shows that 13 patients with EMG-confirmed neurological injury, 10 showed full recovery after 38.50 ± 8.03 months. Furthermore, among 18 patients with NS, 15 had normal urine protein and serum albumin levels after 22.67 ± 10.26 months. CONCLUSIONS: Regulation of skin-lightening cosmetic products, safety surveillance of CFRs, and prevention and control of occupational exposure must be improved to decrease the incidence of mercury poisoning in China.

Blood and Urine Inorganic and Organic Mercury Levels in the United States from 1999 to 2016.

BACKGROUND: Mercury is an environmental hazard. Organic mercury is biologically more toxic than inorganic mercury. Therefore, we studied recent trends in the blood levels of organic and inorganic mercury in the United States. METHODS: A total of 56,445 participants that had blood mercury and urine mercury measurements in National Health and Nutrition Examination Survey (NHANES) 1999-2016 were included. The organic mercury level was obtained by subtracting the inorganic mercury level from the total mercury level. Results were analyzed using SPSS complex sample module version 25. Pregnant women, children ages <20 years, and different ethnicities were analyzed as subgroups. RESULTS: Blood organic mercury level increased from (geometric mean [95% confidence interval]) 0.08 [0.07-0.10] to 0.17 [0.16-0.18] µg/L during 1999-2016. It increased significantly (P <0.001) from 0.03 [0.02-0.03] to 0.07 [0.06-0.07] µg/L in children ages <20 and from 0.14 [0.09-0.21] to 0.36 [0.16-0.83] µg/L in pregnant women in this period (P <0.001). In 2013-2016, non-Hispanic Asians had the highest blood organic mercury level among different ethnicities, 0.93 [0.82-1.05] µg/L (P <0.001). Blood inorganic mercury level decreased from 0.31 [0.31-0.31] in 1999-2000 to 0.21 [0.21-0.22] µg/L in 2015-2016 (P <0.001). Urine mercury level decreased from 0.75 [0.71-0.80] in 1999-2000 to 0.16 [0.16-0.17] µg/L in 2015-2016 (P <0.001). CONCLUSION: Blood organic mercury increased over the period 1999-2016 in the US population, including children and pregnant women, whereas there was a steady decline in both blood inorganic mercury and urine mercury levels.

Mercury intoxication resembling pediatric rheumatic diseases: case series and literature review.

Mercury is the only metal that remains in liquid form at the room temperature. It is a very toxic metal and even short-term exposure can lead to poisoning. Mercury intoxication can affect many systems such as skin, cardiovascular, genitourinary, central and peripheral nervous, respiratory, and musculoskeletal system. Consequently, the diagnosis of mercury intoxication can be challenging due to its non-specific and multisystemic presentation. Herein, we report five pediatric cases with mercury intoxication from two families that were initially misdiagnosed as rheumatic disorders. We also performed a literature review about pediatric cases with mercury intoxication to investigate the clinical findings in children, the source of intoxication, and the current treatment preferences. As in our cases, reported patients were previously misdiagnosed as various infectious and/or rheumatic diseases before the diagnosis of mercury intoxication was established. A delay in diagnosis and treatment can cause serious morbidities and even mortality. We report this case series to emphasize the multisystemic presentation of mercury intoxication, and to remind and provide clues for physicians to recognize this rare toxicologic syndrome.

Application of TDA AAS to Direct Mercury Determination in Postmortem Material in Forensic Toxicology Examinations.

Mercury is a heavy metal with high toxicity, the level of which depends on the form of the metal. One of the newer techniques for determining trace amounts of total mercury in various materials, including biological samples, is thermal decomposition, amalgamation and atomic absorption spectrometry (TDA AAS). The TDA AAS method was optimized and validated using a mercury analyzer (DMA-80). The limits of detection for mercury were 0.10 and 0.20 µg/L (nickel and quartz boats, respectively). The working range of the calibration curve was at least from 0.6 to 200 ng Hg/mL; the intra-day precision in samples (RSD)-in the range of: 1.66-6.86% (blood), 0.82-1.47% (urine) and 2.01-3.44% (hair); the inter-day precision (over 8 days): 2.51%, and 2.5% (blood spiked with 2.5 and 10 ng Hg, respectively), 5.10% and 3.16% (urine spiked with 2.0 and 6.0 ng Hg, respectively). The accuracy (as relative error, mean value) determined on the basis of the study of reference materials of blood (Seronorm Trace Elements Whole Blood L-1, L-2, L-3), urine (Seronorm Trace Elements Urine, Urine L-2), and hair (Human Hair NIES CRM No. 13) was: 2.00% (blood), 0.50% (urine) and 0.86% (hair); recovery of 2.5 ng Hg (blood): 93-97%. The method was used for the determination of mercury in 76 samples of various biological matrices, including samples of whole blood, urine, hair, bile and vitreous humor. Mercury concentrations in postmortem blood (n = 24) were in the range: 0.61-12.4 µg/L (median 3.02 µg/L); urine (n = 12): 0.16-2.19 µg/L (median 0.81 µg/L); hair (n = 14): 0.08-0.53 µg/g (median 0.22 µg/g); bile (n = 12): 1.15-7.11 µg/L (median 2.41 µg/L and vitreous humor (n = 13): 0.22-1.01 µg/L (median 0.47 µg/L). The method is suitable for the purposes of forensic toxicology analysis.

Mercury-induced Oxidative Stress May Adversely Affect Pregnancy Outcome among Dental Staff: A Cohort Study.

BACKGROUND: Dental staff may be at increased risk of adverse pregnancy outcome secondary to their chronic exposure to mercury. OBJECTIVE: To investigate obstetric outcome among dental staff and explore the oxidative stress induced by mercury exposure. METHODS: A cohort of 64 pregnant dental staff (exposed group) and 60 pregnant employees (non-exposed group) were studied. Urinary mercury level and blood antioxidant activity were measured. Participants were followed to assess their obstetric outcome. RESULTS: The exposed group had a higher mean urinary mercury level and a lower blood antioxidant activity during the three trimesters compared to non-exposed group (p<0.001). Women in the exposed group were experienced more frequently spontaneous abortion and pre-eclampsia (p<0.05). Babies born to the women in the exposed group tended to be smaller for gestational age compared to those of non-exposed group (p<0.001). CONCLUSION: Pregnant dental staff suffered higher odds of developing spontaneous abortion and pre-eclampsia and giving birth to babies smaller for gestational age. This may be linked to oxidative stress induced by exposure to mercury.

Endoscopic management of massive mercury ingestion: A case report.

RATIONALE: Ingestion of a massive amount of metallic mercury was thought to be harmless until the last century. After that, in a number of cases, mercury ingestion has been associated with appendicitis, impaired liver function, memory deficits, aspiration leading to pneumonitis and acute renal failure. Treatment includes gastric lavage, giving laxatives and chelating agents, but rapid removal of metallic mercury with gastroscopy has not been used. PATIENT CONCERNS: An 18-year-old man was admitted to our emergency department after drinking 1000 g of metallic mercury as a suicide attempt. DIAGNOSIS: Except from mild umbilical tenderness, he had no other symptoms. Radiography showed a metallic density in the area of the stomach. INTERVENTION: Gastroscopy was performed to remove the mercury. One large pool and several small droplets of mercury were removed from the stomach. OUTCOMES: Blood and urine mercury levels of the patient remained low during hospitalization. No symptoms of mercury intoxication developed during the follow-up period. LESSONS: Massive mercury ingestion may cause several symptoms, which can be prevented with prompt treatment. We used endoscopy to remove the mercury, which shortened the exposure time and minimized the risk of aspiration. This is the first case where endoscopy was used for the management of mercury ingestion.

Intoxicación por mercurio elemental por inyección intramuscular: presentación de caso y revisión de literatura / Poisoning with elemental mercury by intramuscular injection. Case report and review of literature

Se han reportado en la literatura pocos casos de intoxicación por mercurio por administración en tejidos blandos. No se cuenta con suficiente evidencia acerca del manejo con terapia quelante en este tipo de intoxicación. Se reporta el caso de una mujer de 34 años con antecedente psiquiátrico la cual se administró mercurio intramuscular en fosa cubital izquierda con fines autolíticos. Acudió al servicio de urgencias 24 horas posteriores a su administración, el motivo principal fue el dolor intenso en la zona y la presencia de edema, sin efectos sistémicos. La radiografía mostró depósitos metálicos en 1/3 de brazo, localizados en músculo, y que migraron a través de la fascia hacia 2/3 del antebrazo. La placa de tórax no mostró alteraciones. Fue intervenida quirúrgicamente en 3 ocasiones extrayendo mínimas cantidades de mercurio. La paciente fue manejada con antibióticos por presencia de celulitis. Un mes después presentó temblor mercurial, razón por la cual se tomaron muestras de sangre y orina para la determinación de mercurio, el cual resulto elevado en ambas muestras, por lo que se le administró terapia quelante con D-penicilamina.

There are just a few cases of mercury toxicity after administration in soft tissue, reported in the literature. There is insufficient evidence about the management with chelation therapy in this type of poisoning. We report the case of a 34 year-old woman with a psychiatric history who administered herself a mercury injection into de muscle in the left cubital fossa, referred as a suicide attempt. She came to the emergency department 24 hours after administration; the main reason was the intense pain in the area and the presence of edema, with no systemic effects. Radiography showed metallic deposits in 1/3 arm, located in muscle, which moved through the fascia to 2/3 of the forearm. Chest radiography was normal. She underwent surgery trhee times extracting trace amounts of mercury. The patient was managed with antibiotics by the presence of cellulite. One month later she had tremor mercuralis, so a blood and urine samples were sent to the laboratory in order to determinate mercury levels, which resulted high in both fluids, therefore chelation therapy with D-penicillamine was administered.

Ophthalmic findings in acute mercury poisoning in adults: A case series study.

The aim of this study is to report ophthalmic findings of acute mercury poisoning in 48 adults referred to emergency department. Full ophthalmologic examination including the best corrected visual acuity, external eye examination, reaction to light, a slit-lamp examination, funduscopy, intraocular pressure measurements, and visual field (VF) and color vision (CV) tests were performed at the presentation and repeated after 6 months. The parametric values of VF test, the mean deviation (MD), and pattern standard deviation (PSD) were recorded in order to compare patients and the 30 healthy controls. The mean parameter of color confusion index in patients was found to be statistically different than controls (p < 0.01). The MD and PSD in patients were different from controls statistically significant (p < 0.01 and p < 0.01, respectively). There was no correlation between the ocular findings and the urine and blood mercury levels. Methyl mercury, held in the school laboratory for experimental purpose, may be a source of poisoning. In this case series, we showed that acute exposure to mercury had hazardous effect on the visual system, especially CV and VF. We propose that emphasizing the public education on the potential hazards of mercury is crucial for preventive community health.

Occupational exposure to mercury among workers in a fluorescent lamp factory, Quisna Industrial Zone, Egypt.

BACKGROUND: With the fast growth in the market of fluorescent lamps, particularly compact fluorescent light, the associated risk of mercury exposure, which is an essential component in all types of fluorescent lamps, has received increasing public attention worldwide. Even low doses of mercury are toxic. OBJECTIVE: To study the health consequences of occupational exposure to mercury in workers of a fluorescent lamp factory. METHODS: In a cross-sectional study 138 workers of a fluorescent lamp factory and 151 people who had no occupational exposure to mercury (the comparison group) were studied. Environmental study of mercury and noise levels was done. For all participants a neurobehavioral test battery was administered, spirometry was performed and air conduction audiometry was done. Urinary mercury level was also measured for all participants. RESULTS: Prominent symptoms among workers exposed to mercury included tremors, emotional lability, memory changes, neuromuscular changes, and performance deficits in tests of cognitive function. Among the exposed group, the mean urinary mercury level was significantly higher in those who had personality changes or had manifestations of mercury toxicity. With increasing duration of employment and urinary mercury level, the performance of participants in neurobehavioral test battery and spirometric parameters deteriorated. CONCLUSION: Neurobehavioral test battery must be used for studying subclinical central nervous system dysfunction in those with chronic exposure to mercury. The test is especially useful for evaluating the severity of mercury effects in epidemiological studies. This study also reinforces the need for effective preventive programs for fluorescent lamp industry workplaces especially in developing countries with the lowest unhygienic work conditions.

Elemental mercury toxicity due to aspiration following intentional massive ingestion.

Deliberate poisoning with intentional ingestion of elemental mercury is reported not to result in systemic toxicity due to minimal absorption from the gastrointestinal tract. We report a case of a 43 year old male who intentionally ingested 200 ml elemental mercury which resulted in abdominal pain and vomiting. The patient subsequently aspirated globules of mercury which was confirmed on chest x-ray and his blood mercury levels were markedly raised. He was treated with chelating agents and managed in a negative pressure room to reduce the risk of staff being exposed to exhaled mercury vapour from the patient.

Acute mercury poisoning among children in two provinces of Turkey.

Elemental mercury exposure occurs frequently and is potentially a toxic, particularly in children. Children are often attracted to elemental mercury because of its color, density, and tendency to form beads. Clinical manifestations of elemental mercury intoxication vary depending on its form, concentration, route of ingestion, and the duration of exposure. We present data on 179 pediatric cases of elemental mercury poisoning from exposure to mercury in schools in two different provinces of Turkey. Of all patients, 160 children had both touched/played with the mercury and inhaled its vapors, while 26 children had only inhaled the mercury vapor, two children reported having tasted the mercury. The median duration of exposure was 5 min (min 1-max 100), and 11 (6 %) children were exposed to the mercury for more than 24 h at home. More than half of the children (51.9 %) were asymptomatic at admission. Headache was the most common presenting complaint. The results of physical and neurological examinations were normal in 80 (44.6 %) children. Mid-dilated/dilated pupils were the most common neurological abnormality, and this sign was present in 90 (50.2 %) children. Mercury levels were measured in 24-h urine samples daily, and it was shown that the median urinary level of mercury was 29.80 µg/L (min, 2.40 µg/L; max, 4,687 µg/L). A positive correlation was also found between the duration of exposure and urinary mercury levels (r = 0.23, p = 0.001). All patients were followed up for 6 months. On the first follow-up visit performed 1 month after discharge, the neurological examinations of all patients were normal except for those patients with peripheral neuropathy and visual field defects. On the last follow-up visit at the sixth month, only two children still experienced visual field defects. In conclusion, this study is one of the largest case series of mercury intoxication of students in schools. Elemental mercury exposure can be potentially toxic, and its symptomatology is variable, particularly in children. Therefore, school staff and children should be aware of the risk of mercury toxicity. Pediatricians also need to warn parents and children about the hazards of playing with any chemical.

[Metallic mercury poisoning caused by intravenous injection in vague circumstances--a case report]. / Zatrucie rtecia metaliczna podana dozylnie w niejasnych okolicznosciach--opis przypadku.

UNLABELLED: Mercury is a heavy metal found in nature in three forms: metallic mercury, organic and inorganic compounds. It is a general protoplasmatic toxin. The pathophysiology of mercury toxicity is related to its binding to sulfhydryl groups of different receptor proteins and cellular enzymes, interrupting cellular metabolism and in this way causing cell death. In the paper we present a case of 57-year-old woman, who was admitted due to suspicion of metallic mercury parenteral poisoning. The computed tomography (CT) scan of abdomen accidentally revealed multiple disseminated tiny metallic densities. The blood mercury level was high (41.9 microg/l), as well as mercury urine level (85.7 microg/g creatinine which was 42.8 microg/l). Neurologic examination revealed unobtrusive symptoms of cerebellum affection. Psychological examination revealed disturbances of cognitive abilities reliant on the efficiency of vision organ. The results of A. Benton's organic test were abnormal. Psychiatric examination revealed no abnormalities. Results of pulmonary function tests were within normal limits. CONCLUSIONS: The intravenous injection of metallic mercury did not cause serious clinical effects. Followup examination in order to reveal chronic toxic effects is necessary. Diagnostics and treatment of metallic mercury intoxications by parenteral injection should be carried out in the clinical toxicology departments.

[Long-term follow-up after intravenous injection of mercury--two cases report]. / Wieloletnia obserwacja po dozylnym wstrzyknieciu rteci metalicznej--opis dwóch przypadków.

In this paper we present the long-term follow-up of two patients, after injection of metallic mercury. Case 1. In 1997, 29-years-old man injected himself to left elbow about 20 ml of metallic mercury by mistake (he was heroin abuser for short time). Mercury concentration in the blood was 400 microg/L. X-ray of the chest, abdomen and affected elbow area showed radiopaque foreign material (depots of mercury). Depots of mercury were also visible on the tricuspid valve in echocardiography. Mercury from the soft tissue left elbow pit was partially surgically removed. During 15 years follow-up two times chelating therapy was performed with d-penicyllamine and DMPS. In 2012, he was admitted to hospital next time. The blood and urine mercury concentration was still elevated (55.2 microg/L and 197 microg/L), mercury depots in the lung and abdomen were present. The signs and symptoms of CNS damage, like peripheral polyneuropathy and ataxia, were diagnosed. CT of brain did not revealed any changes, despite head trauma before 6 years. However neurological findings are typical for chronic mercury poisoning, it is not possible to determine whether these changes are directly related to mercury, because head trauma history, Case 2. In 2003, 16-years-old woman injected herself one month before, in suicidal attempts to both elbows several millilitres of metallic mercury. Mercury concentration in the blood was 56.2 microg/L, in urine 906 microg/L and in the hair 1.12 microg/g. Chest Xray showed depots of mercury in the lung. Mercury from the soft tissue was two times surgically removed. During 9 years two times chelating therapy was performed with d-penicyllamine and DMPS. After 9 years there is no symptoms of mercury poisoning. Mercury depots in the lung are still present. The blood and urine mercury concentration is low (13.7 microg/L and 2.53 microg/L). In mean time she gave birth two healthy children. Further patients evaluation is necessary.

Mercury vapor inhalation and poisoning of a family.

Acute mercury vapor poisoning is a rare but fatal toxicological emergency. People are exposed to mercury in daily life by the way of foods, vaccines, antiseptics, ointments, amalgam or occupation. We present here, the clinical picture and management of four members of the same family who were exposed to elemental mercury. Three of the family members were seen in another hospital with malaise, fever, eritematous rash and pulmonary problems. Their questioning revealed the mercury exposure. Having a suspicion of heavy metal intoxication, blood and urine mercury levels were measured and mercury intoxication was diagnosed. On admission to our hospital, two patients already had chelation therapy. In three of them we found three distinct abnormalities: encephalopathy, nephrotic syndrome and polyneuropathy. The fourth family member had minor symptoms. This family is an example for the inhalation exposure resulting from inappropriate handling of liquid mercury. During the first days, flu like illness ensues. Then, severe pulmonary, neurological, renal, hepatic, hematological and dermatological dysfunctions develop. Blood and urine mercury levels should be tested on suspicion, but it must be kept in mind that blood level is unreliable in predicting the severity of mercury toxicity. The priority in the treatment should be removing the patient from the source of exposure. Then British anti-Lewisite, edetate calcium disodium, penicillamine, Sodium 2,3-dimercaptopropane-1-sulfhonate and 2,3-dimercaptosuccinic acid can be used for binding the mercury. We conclude that since mercury-containing devices are present in daily life, physicians must be able to recognize the clinical manifestations and treatment of mercury poisoning.

Impact of occupational exposure to elemental mercury on some antioxidative enzymes among dental staff.

OBJECTIVES: The aim of this study is to investigate the effect of elemental mercury exposure on renal function and antioxidative enzymes activity as a possible mechanism of renal affection among dental staff. METHODS: This study was performed on a group of dental staff exposed to elemental mercury (N = 32) and matched control group (N = 37). Urinary and blood level of mercury, albumin α1 microgloblin in urine, glutathione peroxidase and superoxide dismutase blood level were measured for the exposed and control group. RESULTS: Compared to the control group, urinary and blood mercury were significantly higher in the exposed group. Glutathione peroxidase and superoxide dismutase activities in blood were significantly decreased and were negatively correlated with duration of work. CONCLUSION: Oxidative stress is an important molecular mechanism for renal dysfunction in mercury exposure, manifested by decreased activities of antioxidant enzymes.

Care of patients who are worried about mercury poisoning from dental fillings.

INTRODUCTION: Public concern about adverse health effects from mercury exposure from dental amalgams remains a high-profile issue. Patients with nonspecific neuropsychiatric symptoms may incorrectly attribute their complaints to mercury poisoning, and some alternative medical providers diagnose mercury toxicity using nonvalidated tests or without testing at all. CASE REPORT: We report the case of a 37-year-old female who was referred to our outpatient medical toxicology clinic by her family medicine physician after a wellness doctor involved in her care ordered a dimercaptopropanesulfonic acid (DMPS) challenge urine study that revealed an "elevated" mercury level. DISCUSSION: The use of postchelator challenge urine testing to diagnose mercury poisoning has not been validated. Use of such tests may cause falsely elevated urine mercury levels resulting in misdiagnosis of mercury poisoning and unncessary, expensive, and potentially dangerous chelation therapy. CONCLUSION: Family medicine physicians may encounter patients who are concerned about mercury poisoning after undergoing postchelator challenge urine testing. In patients with a low suspicion for mercury toxicity, reassurance is adequate. In patients with moderate to high suspicion for mercury toxicity, a validated test for mercury, such as a 24-hour urine mercury level, or referral to a medical toxicologist is the most appropriate approach.

[The cardiovascular risk in chemical factory workers exposed to mercury vapor]. / Ryzyko sercowo-naczyniowe u narazonych na dzialanie par rteci pracowników zakladów chemicznych.

BACKGROUND: Cardiovascular diseases, including hypertension, are a leading cause of death in developing and developed countries. Mercury can induce hypertension and atherosclerosis in experimental animals and humans. The assessment of the effect of mercury on the occurrence of cardiovascular system disturbances in the population is an essential task. The aim of this study was to assess the association between mercury concentration in urine and the risk of fatal cardiovascular disease during ten coming years. MATERIAL AND METHODS: The study included chemical factory workers who used mercury in the chlorine production. RESULTS: The mean urine concentration of mercury in 154 workers was 4.9 +/- 11.2 microg/g creatinine. The most common disease was hypertension. CONCLUSIONS: The cardiovascular risk was higher in workers exposed to small or moderate mercury levels than in workers exposed to mercury vapor in high concentrations. Furthermore, the negative association was observed between mercury exposure and smoking in workers with low urinary excretion of mercury.