Evaluating the accuracy of Chat Generative Pre-trained Transformer version 4 (ChatGPT-4) responses to United States Food and Drug Administration (FDA) frequently asked questions about dental amalgam.

BACKGROUND: The use of artificial intelligence in the field of health sciences is becoming widespread. It is known that patients benefit from artificial intelligence applications on various health issues, especially after the pandemic period. One of the most important issues in this regard is the accuracy of the information provided by artificial intelligence applications. OBJECTIVE: The purpose of this study was to the frequently asked questions about dental amalgam, as determined by the United States Food and Drug Administration (FDA), which is one of these information resources, to Chat Generative Pre-trained Transformer version 4 (ChatGPT-4) and to compare the content of the answers given by the application with the answers of the FDA. METHODS: The questions were directed to ChatGPT-4 on May 8th and May 16th, 2023, and the responses were recorded and compared at the word and meaning levels using ChatGPT. The answers from the FDA webpage were also recorded. The responses were compared for content similarity in "Main Idea", "Quality Analysis", "Common Ideas", and "Inconsistent Ideas" between ChatGPT-4's responses and FDA's responses. RESULTS: ChatGPT-4 provided similar responses at one-week intervals. In comparison with FDA guidance, it provided answers with similar information content to frequently asked questions. However, although there were some similarities in the general aspects of the recommendation regarding amalgam removal in the question, the two texts are not the same, and they offered different perspectives on the replacement of fillings. CONCLUSIONS: The findings of this study indicate that ChatGPT-4, an artificial intelligence based application, encompasses current and accurate information regarding dental amalgam and its removal, providing it to individuals seeking access to such information. Nevertheless, we believe that numerous studies are required to assess the validity and reliability of ChatGPT-4 across diverse subjects.

Imaging gastrointestinal damage due to acute mercury poisoning using a mitochondria-targeted dual near-infrared fluorescent probe.

Mercury (Hg) is one of the most widespread pollutants that pose serious threats to public health and the environment. People are inevitably exposed to Hg via different routes, such as respiration, dermal contact, drinking or diet. Hg poisoning could cause gingivitis, inflammation, vomiting and diarrhea, respiratory distress or even death. Especially during the developmental stage, there is considerable harm to the brain development of young children, causing serious symptoms such as intellectual disability and motor impairments, and delayed neural development. Therefore, it's of great significance to develop a specific, quick, practical and labor-saving assay for monitoring Hg2+. Herein, a mitochondria-targeted dual (excitation 700 nm and emission 728 nm) near-infrared (NIR) fluorescent probe JZ-1 was synthesized to detect Hg2+, which is a turn-on fluorescent probe designed based on the rhodamine fluorophore thiolactone, with advantages of swift response, great selectivity, and robust anti-interference capability. Cell fluorescence imaging results showed that JZ-1 could selectively target mitochondria in HeLa cells and monitor exogenous Hg2+. More importantly, JZ-1 has been successfully used to monitor gastrointestinal damage of acute mercury poisoning in a drug-induced mouse model, which provided a great method for sensing Hg species in living subjects, as well as for prenatal diagnosis.

Single-Nucleotide Polymorphisms Associated with Mercury Levels and Neurological Symptoms: An Overview.

Mercury (Hg) pollution is a global public health concern because of its adverse effects on the environment and health. Single-nucleotide polymorphisms (SNPs) have been associated with Hg levels and outcomes. The aim of this review was to describe the research and discuss the evidence on the genetic susceptibility of Hg-exposed individuals to the development of neurocognitive disorders. A systematic review was performed to identify the genes/SNPs associated with Hg toxicokinetics and that, therefore, affect neurological function in exposed populations. Observational and experimental studies were identified by screening three databases. Thirteen articles were included (quality score 82-100%) and 8124 individuals were evaluated. Hg exposure was mainly fish consumption (77%) and, in 31% of the studies, the Hg levels exceeded the reference limits. Genetic susceptibility to higher Hg levels and neurotoxicity risk in Hg poisoning were associated with eight (ALAD rs1800435, CYP3A4 rs2740574, CYP3A5 rs776746, CYP3A7 rs2257401, GSTP1 rs1695, MT1A rs8052394, MT1M rs2270836, and MT4 rs11643815) and three (MT1A rs8052394, MT1M rs2270837, and MT2A rs10636) SNPs, respectively, and rs8052394 was associated with both outcomes. The MT1A rs8052394 SNP may be used as a susceptibility biomarker to identify individuals at greater risk for higher Hg levels and the development of neurocognitive disorders in metal-exposed populations.

Long-Term Environmental Methylmercury Exposure Is Associated with Peripheral Neuropathy and Cognitive Impairment among an Amazon Indigenous Population.

Widespread contamination of the Amazon basin with mercury has been reported to occur since at least the mid-80s due to heavy gold mining activity. Although initial studies have indicated that this may lead to deleterious neurological consequences to the indigenous populations living in the region, further research is needed to better characterize the neurological burden of such long-term exposure. With this aim, a cross-sectional exploratory study has been conducted with the Yanomami indigenous population residing in a northern Amazon region. All participants underwent a structured interview; detailed neurological examination, including assessment for cognitive, motor, coordination, and sensory functions; and laboratorial testing for serum hemoglobin, blood glucose, and methylmercury levels in hair samples. This study enrolled 154 individuals of 30.9 ± 16.8 years of age, of which 56.1% were female. Mean methylmercury levels in hair were 3.9 ± 1.7 µg/g. Methylmercury levels in hair > 6.0 µg/g were found in 10.3%. Among participants with hair methylmercury levels ≥ 6.0 µg/g, the prevalences of peripheral neuropathy and reduced cognitive performance were, respectively, 78.8% (95%CI 15-177%, p = 0.010) and 95.9% (95%CI 16-230.8%, p = 0.012) higher than those of individuals with lower levels. These results suggest that chronic mercury exposure may lead to significant and potentially irreversible neurotoxicity to Yanomami population living in the northern Amazon basin.

Pathology of human organic mercury poisoning: Lessons from an autopsy case.

We had an opportunity to perform a general autopsy of a case with chronic organic mercury toxicosis in 2017. He had been engaged in synthesizing a variety of organic mercury compounds throughout the four years from 1966 and developed chronic organic mercury poisoning in 1969. Almost forty years on, he still remained to complain of persistent paresthesia at finger tips and tongue, and of narrowed visual field. Neurological examinations clarified a rise of two-point discrimination thresholds, a systemic increase of touch thresholds, constriction of the visual field caused by general visual depression, and sensorineural hearing loss while primary modalities of his somatic, visual, and auditory sensations were preserved. These symptoms and signs are characteristic of human organic mercury poisoning. Furthermore, he had difficulty in processing a lot of visual and auditory information at a time. His two-point discrimination thresholds and systemic elevation of touch thresholds were comparable to those of mild organic mercury poisoning cases. He had slight sensory ataxia, but not cerebellar ataxia. Brain [18F]-2-fluorodeoxyglucose positron emission tomography analysis exhibited marked hypometabolism at bilateral postcentral gyrus, striate cortex, and superior temporal gyrus, but not the cerebellum. Histopathological studies revealed considerable decrease of granular neurons and neuronal networks in bilateral primary somatosensory, visual, and auditory cortices. Those characteristic brain lesions fairly explain increase of thresholds of somatic, visual, and auditory sensations, and degradation of integrating sensory information. It is noted that damages to the peripheral nervous system and the cerebellum were not detected and that his intellectual faculties were preserved.

Monitoring Hg2+ and MeHg+ poisoning in living body with an activatable near-infrared II fluorescence probe.

Noninvasively imaging mercury poisoning in living organisms is critical to understanding its toxicity and treatments. Especially, simultaneous fluorescence imaging of Hg2+ and MeHg+in vivo is helpful to disclose the mysteries of mercury poisoning. The key limitation for mercury imaging in vivo is the low imaging signal-to-background ratio (SBR) and limited imaging depth, which may result in unreliable detection results. Here, we designed and prepared a near-infrared II (NIR II) emissive probe, NIR-Rh-MS, leveraging the "spirolactam ring-open" tactic of xanthene dyes for in situ visualization of mercury toxicity in mice. The probe produces a marked fluorescence signal at 1015 nm and displays good linear responses to Hg2+ and MeHg+ with excellent sensitivity, respectively. The penetration experiments elucidate that the activated NIR-II fluorescence signal of the probe penetrates to a depth of up to 7 mm in simulated tissues. Impressively, the probe can monitor the toxicity of Hg2+ in mouse livers and the accumulation of MeHg+ in mouse brains via intravital NIR-II imaging for the first time. Thus, we believe that detecting Hg2+ and MeHg+ in different organs with a single NIR-II fluorescence probe in mice would assuredly advance the toxicologic study of mercury poisoning in vivo.

[Report on a case of significant increase in urine mercury due to excessive mercury in cosmetics].

Mercury is highly toxic and can be absorbed through skin contact. From December 5, 2020 to February 16, 2021, occupational disease laboratory of the First People's Hospital of Baiyin received 30 urine mercury test samples from a beauty salon in Lanzhou City. The test results showed that 28 samples exceeded the normal value (normal value: 4 µg/g Cr) . 15 patients were treated with sodium dimertopropyl sulfonate for mercury removal and tiopron for liver protection, and the prognosis was good.

Report on a case of significant increase in urine mercury due to excessive mercury in cosmetics / 中华劳动卫生职业病杂志

Mercury is highly toxic and can be absorbed through skin contact. From December 5, 2020 to February 16, 2021, occupational disease laboratory of the First People's Hospital of Baiyin received 30 urine mercury test samples from a beauty salon in Lanzhou City. The test results showed that 28 samples exceeded the normal value (normal value: 4 μg/g Cr) . 15 patients were treated with sodium dimertopropyl sulfonate for mercury removal and tiopron for liver protection, and the prognosis was good.

Roadmap to mercury-free dentistry era: Are we prepared?

From the perspectives of longevity, mechanical performance, and economics, amalgam has long been considered the material of choice, especially for certain types of restorations in posterior teeth, including replacement therapy for existing amalgam fillings. In spite of numerous advantages over other filling materials, its use has been decreasing in recent years and the alternative tooth-colored filling materials are increasingly used. There is a trend towards minimal interventional, adhesive, techniques in dentistry, which are based on adhesion to tooth structure by chemical interaction and/or micromechanical retention. At the same time, the quality and durability of alternative materials have improved. Mercury is the metallic element of concern used in dental amalgam. Mercury is a well-documented toxicant, with reasonably well-defined characteristics for the major forms of exposure, involving elemental mercury as well as organic and inorganic mercury compounds. Looking into the kind of practice and its popularity among dentists and the patients in India, even we have to comply with the use of amalgam by implementing the best possible ways to minimize the extent of damage to nature.

Heavy metals intoxication in a patient with POEMS-like symptoms: a case report.

BACKGROUND: POEMS syndrome (polyneuropathy, organomegaly, endocrinopathy, M-protein, skin changes) is a kind of plasma cell disease with complex clinical manifestations involving multiple systems. Metal poisonings through a mucocutaneous are rare in clinic and reported less in the literature. People may exposure to toxic metals through air, food, water, or inappropriate use of drugs. Acute or chronic poisonings can lead to various toxic effects on body tissues and organs. Both POEMS syndrome and heavy metal intoxication are uncommon with multifarious and nonspecific clinical manifestations. Here we describe a case of a 54-year-old man with polyarticular pain and IgA lambda type monoclonal protein in his serum. The diagnosis was confirmed by heavy metals testing in his urine and the herbal mixtures he took. This is the first available report of arsenic and mercury intoxication mimicking POEMS syndrome.

Toxic Nephropathy Secondary to Chronic Mercury Poisoning: Clinical Characteristics and Outcomes.

Introduction: Kidney disease secondary to mercury poisoning has not been well documented and is often misdiagnosed and mistreated. Methods: We performed a retrospective analysis of patients diagnosed with having mercury poisoning over a 6-year period between July 2013 and June 2019. Demographics, clinical measures, renal pathologic examinations, treatments, and outcomes were compared between patients with kidney disease and those without kidney disease. Results: Of the 172 patients with mercury poisoning, 46 (26.74%) had renal damage. Among the 46 patients, 41 (89.13%) presented nephrotic syndrome, and 5 (10.87%) showed proteinuria alone. The pathologic abnormality associated with kidney disease caused by mercury poisoning was mainly membranous nephropathy (18 of 35 patients, 51.43%). Among 41 patients with nephrotic syndrome, 25 were treated with chelation therapy alone and 12 with mercury chelation therapy and glucocorticoids. The remaining 4 patients were treated with chelation therapy, glucocorticoids, and immunosuppressive therapies. The overall effective rate was 97.5% (40 patients). There was no significant difference in complete remission rate among the 3 treatment methods (P < 0.05). Conclusion: The main clinical manifestation of kidney disease secondary to chronic mercury poisoning was nephrotic syndrome, which was reflected in pathologic examinations as membranous nephropathy. Kidney disease to chronic mercury poisoning is prone to misdiagnosis and missed diagnosis. Chelation therapy is the main treatment, and the prognosis is good. Patients with severe condition can be supplemented with glucocorticoid.

[Study on the difference of curative effect of conventional mercury displacement treatment on mercury in brain and kidney].

Objective: To explore the expulsion effect of sodium dimercaptopropanesulfonate (DMPS) on mercury in different organs of mercury poisoning and the therapeutic effect of glutathione (GSH) combined with antioxidant therapy on mercury poisoning. Methods: In February 2019, 50 SPF male SD rats were randomly divided into 5 groups, 10 rats in each group: A (saline negative control group) , B (HgCL2 positive control group) , treatment group (C: intramuscular injection of DMPS 15 mg/kg treatment, D: intramuscular injection of DMPS30 mg/kg treatment, E: intramuscular injection of DMPS 15 mg/kg and intraperitoneal injection of GSH200 mg/kg treatment) . Rats in group B, C, D and E were subcutaneously injected with mercury chloride solution (1 mg/kg) to establish a rat model of subacute mercury poisoning kidney injury. Rats in group A were subcutaneously injected with normal saline. After the establishment of the model, rats in the treatment group were injected with DMPS and GSH. Rats in group A and group B were injected with normal saline. At 21 d (treatment 7 d) and 28 d (treatment 14 d) after exposure, urine and blood samples of 5 rats in each group were collected. Blood biochemistry, urine mercury, urine microalbumin and mercury content in renal cortex, cerebral cortex and cerebellum were detected. Results: After exposure to mercury, the contents of mercury in renal cortex, cerebrum and cerebellum of rats in group B, C, D and E increased, and urine microalbumin increased. Pathology showed renal tubular injury and renal interstitial inflammation. Compared with group B, urinary mercury and renal cortex mercury in group C, D and E decreased rapidly after DMPS treatment, and there was no significant decrease in mercury levels in cerebellum and cerebral cortex of rats, accompanied by transient increase in urinary albumin after DMPS treatment (P<0.05) ; the renal interstitial inflammation in group E was improved after GSH treatment. There was a positive correlation between urinary mercury and the contents of mercury in renal cortex, cerebral cortex and cerebellum (r=0.61, 0.47, 0.48, P<0.05) . Conclusion: DMPS mercury expulsion treatment can significantly reduce the level of metal mercury in the kidney, and there is no significant change in the level of metal mercury in the cortex and cerebellum.

Molecular Fates of Organometallic Mercury in Human Brain.

Mercury is ubiquitous in the environment, with rising levels due to pollution and climate change being a current global concern. Many mercury compounds are notorious for their toxicity, with the potential of organometallic mercury compounds for devastating effects on the structures and functions of the central nervous system being of particular concern. Chronic exposure of human populations to low levels of methylmercury compounds occurs through consumption of fish and other seafood, although the health consequences, if any, from this exposure remain controversial. We have used high energy resolution fluorescence detected X-ray absorption spectroscopy to determine the speciation of mercury and selenium in human brain tissue. We show that the molecular fate of mercury differs dramatically between individuals who suffered acute organometallic mercury exposure (poisoning) and individuals with chronic low-level exposure from a diet rich in marine fish. For long-term low-level methylmercury exposure from fish consumption, mercury speciation in brain tissue shows methylmercury coordinated to an aliphatic thiolate, resembling the coordination environment observed in marine fish. In marked contrast, for short-term high-level exposure, we observe the presence of biologically less available mercuric selenide deposits, confirmed by X-ray fluorescence imaging, as well as mercury(II)-bis-thiolate complexes, which may be signatures of severe poisoning in humans. These differences between low-level and high-level exposures challenge the relevance of studies involving acute exposure as a proxy for low-level chronic exposure.

Exposição ao mercúrio e anemia em crianças e adolescentes de seis comunidades da Amazônia Brasileira / Mercury exposure and anemia in children and adolescents from six riverside communities of Brazilian Amazon

Resumo O mercúrio (Hg) é uma substância tóxica, sendo o consumo de pescados uma das principais fontes de exposição da população. Este artigo visa avaliar a associação entre anemia e exposição ao Hg na população infanto-juvenil de seis comunidades ribeirinhas da Amazônia Brasileira. Realizou-se a análise secundária de dados de estudos seccionais, incluindo 1.318 indivíduos, divididos em dois grupos segundo a influência do garimpo (grupo A sob influência, e grupo B sem influência). Métodos de análise multivariada foram realizados para verificar a associação entre variável de exposição (Hg no cabelo) e anemia, estratificando pelos grupos. Foram observados 348 casos de anemia (27,1%), sendo 206 entre o grupo B e 142 no grupo A. Houve diferença na mediana dos níveis de Hg entre os grupos (A = 12,8µg/g e B = 4,3µg/g, p = 0,01). Foi observada associação entre Hg no cabelo ≥ 6,0µg/g e anemia (OR = 1,38; IC95% = 1,02-1,87), fato que foi magnificado para o grupo A quando realizada estratificação (OR = 2,23; IC95% = 1,28-3,90). O estudo mostrou elevados níveis de Hg, principalmente no grupo A, e que essa substância pode ser um possível fator de risco para anemia. Além disso, as áreas geográficas pareceram modificar esse efeito, apontando para influência de outros fatores, fato que deve ser melhor avaliado.

Abstract Mercury (Hg) is a toxic substance, and fish consumption is one of the main sources of exposure for the population. This article aims to evaluate the association between exposure to Hg and anemia among children and adolescents from six riverside communities in the Brazilian Amazon. Secondary data analysis from cross-sectional studies, including 1,318 individuals, divided into two groups according to gold mining exposure (group A under the influence, and group B without it). Multivariate analysis methods were performed to assess the association between exposure to Hg (hair Hg) and anemia, stratifying by groups. Three hundred and forty-eight anemia cases were observed (27.1%), with 206 from group B and 142 out of group A. There was a difference in the median of Hg levels between groups (A = 12.8µg/g and B = 4.3µg/g, p = 0.01). An association was observed between hair Hg levels ≥ 6.0µg/g and anemia (OR = 1.38; 95%CI = 1.02-1.87), a fact that was magnified for group A, when stratification was performed (OR = 2.23; 95%CI = 1.28-3.90). This study showed high Hg levels, especially in group A and this substance might be a possible risk factor for anemia. Also, geographical areas seemed to modify this effect, pointing to the influence of other factors, which should be better evaluated.

Comprehensive Review Regarding Mercury Poisoning and Its Complex Involvement in Alzheimer's Disease.

Mercury (Hg) is considered one of the most widespread toxic environmental pollutants, which seems to have multiple effects on organisms even at low concentrations. It has a critical role in many health problems with harmful consequences, with Hg primarily targeting the brain and its components, such as the central nervous system (CNS). Hg exposure was associated with numerous CNS disorders that frequently trigger Alzheimer's disease (AD). Patients with AD have higher concentrations of Hg in blood and brain tissue. This paper aims to emphasize a correlation between Hg and AD based on the known literature in the occupational field. The outcome shows that all these concerning elements could get attributed to Hg. However, recent studies did not investigate the molecular level of Hg exposure in AD. The present review highlights the interactions between Hg and AD in neuronal degenerations, apoptosis, autophagy, oxidative stress (OS), mitochondrial malfunctions, gastrointestinal (GI) microflora, infertility and altering gene expression.

Mercury Exposure in Artisanal Mining: Assessing the Effect of Occupational Activities on Blood Mercury Levels Among Artisanal and Small-Scale Goldminers in Ghana.

A cross-sectional survey of 425 male artisanal and small-scale goldminers (ASGM) was conducted to examine the relationship between the occupational activities of the miners and their blood mercury levels while controlling for relevant biosocial and socio-cultural factors. The data was subjected to descriptive and inferential statistics. Initial findings showed that 43.29% of the ASGM miners had blood mercury levels above the occupational exposure threshold. Among the occupational factors, ASGM miners who amalgamate gold, burn amalgam, and ASGM miners who smelt gold were 2.260, 1.881, and 2.094 times respectively more likely to have high blood mercury levels as compared to ASGM miners who did not carry out these activities. Also, ASGM miners who suck excess mercury with their mouth (OR = 0.197, p < 0.001) were less likely to have high blood mercury levels. For the biosocial and socio-cultural attributes, high blood mercury levels was less likely among older ASGM miners (OR = 0.507, p < 0.05). Inversely, high blood mercury levels was more likely among ASGM miners who are married (OR = 1.627, p < 0.05), ASGM miners with junior (OR = 2.240, p < 0.001) and senior (OR = 1.575, p < 0.05) high school education, and ASGM miners who have 6-10 years (OR = 3.802, p < 0.001) and above 10 years (OR = 2.591, p < 0.001) work experience. ASGM miners who amalgamate gold, burn amalgam, and smelt gold are exposed to mercury and are at risk of mercury poisoning. This could, however, be minimized with the right capturing devices and personal protective equipment. This notwithstanding, unsafe, and unsustainable occupational practices such as working in mercury contaminated water and sucking excess mercury with the mouth should be discouraged.

Uma revisão de escopo de revisões sistemáticas sobre exposição humana ao mercúrio / A scoping review of systematic reviews on human exposure to mercury

Resumo: Introdução: a promulgação da Convenção de Minamata no Brasil em 2018 incentivou o cumprimento dos seus objetivos em reduzir o uso e a poluição por mercúrio. Objetivo: caracterizar a produção científica sobre exposição humana ao mercúrio e identificar lacunas de conhecimento a fim de subsidiar a tomada de decisão em saúde. Métodos: revisão de escopo de revisões sistemáticas e metanálises, sem restrição de idioma ou data de publicação, utilizando as bases PubMed, BVS e Cochrane Library. Resultados: 71 estudos atenderam aos critérios de elegibilidade, com 40 revisões sistemáticas, 30 metanálises e 1 overview. Amálgama dentário e contaminação alimentar e ambiental por atividades que utilizam mercúrio foram as fontes de exposição mais mencionadas. Os temas mais estudados contaram com transtornos mentais e comportamentais, assim como uso de biomarcadores e testes neurocomportamentais relacionados à exposição ao mercúrio. Discussão: lacunas como a exposição ocupacional ao mercúrio, uso em práticas tradicionais e em cosméticos apontam para a necessidade de mais estudos. As revisões identificadas podem oferecer subsídios para sínteses de evidências e protocolos de atenção à saúde de populações expostas, assim como para a elaboração de políticas públicas que visem o controle do uso e da exposição ao mercúrio.

Abstract: Introduction: in 2018, the promulgation of the Minamata Convention in Brazil encouraged compliance with its goals of reducing mercury use and pollution. Objective: to characterize the scientific production and identify the knowledge gaps to subsidize decision-making in healthcare on human exposure to mercury. Methods: a scoping review was carried out of systematic reviews and metanalysis, without language and publication date restriction, retrieved from the PubMed, BVS, and Cochrane Library databases. Results: a total of 71 studies met the eligibility criteria, of which 40 were systematic reviews, 30 meta-analyses, and one overview. Dental amalgam as well as food and environmental contamination by mercury-based activities were the most cited sources of exposure. Most studies focused on mental and behavioral disorders, as well as the use of biomarkers and neurobehavioral tests related to mercury exposure. Discussion: knowledge gaps on occupational exposure to mercury, mercury use in both traditional practices and cosmetics point to the need for further studies. The reviews identified could provide data for evidence synthesis and healthcare protocols for affected populations, as well as for elaborating public policies aimed at controlling mercury use and exposure.

Study on the difference of curative effect of conventional mercury displacement treatment on mercury in brain and kidney / 中华劳动卫生职业病杂志

Objective: To explore the expulsion effect of sodium dimercaptopropanesulfonate (DMPS) on mercury in different organs of mercury poisoning and the therapeutic effect of glutathione (GSH) combined with antioxidant therapy on mercury poisoning. Methods: In February 2019, 50 SPF male SD rats were randomly divided into 5 groups, 10 rats in each group: A (saline negative control group) , B (HgCL2 positive control group) , treatment group (C: intramuscular injection of DMPS 15 mg/kg treatment, D: intramuscular injection of DMPS30 mg/kg treatment, E: intramuscular injection of DMPS 15 mg/kg and intraperitoneal injection of GSH200 mg/kg treatment) . Rats in group B, C, D and E were subcutaneously injected with mercury chloride solution (1 mg/kg) to establish a rat model of subacute mercury poisoning kidney injury. Rats in group A were subcutaneously injected with normal saline. After the establishment of the model, rats in the treatment group were injected with DMPS and GSH. Rats in group A and group B were injected with normal saline. At 21 d (treatment 7 d) and 28 d (treatment 14 d) after exposure, urine and blood samples of 5 rats in each group were collected. Blood biochemistry, urine mercury, urine microalbumin and mercury content in renal cortex, cerebral cortex and cerebellum were detected. Results: After exposure to mercury, the contents of mercury in renal cortex, cerebrum and cerebellum of rats in group B, C, D and E increased, and urine microalbumin increased. Pathology showed renal tubular injury and renal interstitial inflammation. Compared with group B, urinary mercury and renal cortex mercury in group C, D and E decreased rapidly after DMPS treatment, and there was no significant decrease in mercury levels in cerebellum and cerebral cortex of rats, accompanied by transient increase in urinary albumin after DMPS treatment (P<0.05) ; the renal interstitial inflammation in group E was improved after GSH treatment. There was a positive correlation between urinary mercury and the contents of mercury in renal cortex, cerebral cortex and cerebellum (r=0.61, 0.47, 0.48, P<0.05) . Conclusion: DMPS mercury expulsion treatment can significantly reduce the level of metal mercury in the kidney, and there is no significant change in the level of metal mercury in the cortex and cerebellum.

Long-term visual pathway alterations after elemental mercury poisoning: report of a series of 29 cases.

BACKGROUND: There are few clinical data on retinal involvement after acute exposure to high concentrations mercury and the available reports are based on a small number of patients suffering chronic exposure. The purpose of this paper is to report findings in workers acutely exposed to very high concentrations of mercury vapor with the aim of providing data on a possible direct retinal involvement. METHODS: Twenty-nine patients and 16 controls were evaluated in a comparative case series. Mercury levels in blood and urine samples, visual acuity (VA), contrast sensitivity (CS), visual field (VF), color discrimination and optical coherence tomography (OCT) were recorded. The pattern reversal visual-evoked potentials (PRVEP), full-field and multifocal electroretinography (ffERG/mfERG), pattern electroretinography (PERG), systemic symptoms, presence of erethism, and electromyography (EMG) were also gathered. A descriptive analysis was performed. The correlations between variables also were studied. In addition, electrophysiological data from those patients with deeper VF defects (group 1) were compared with a normal control group. RESULTS: Twenty-six workers exhibited symptoms of erethism. The EMG showed sensorimotor polyneuropathy and multiple mononeuropathy. The VA was slightly affected in 48.27% (n = 14) of subjects. Loss of CS in at least one of four spatial frequencies and color vision alterations occurred in 96.5% (n = 28) and 44.8% (n = 13), respectively. VF alterations were identified in 72.4% (n = 21) patients. No morphologic changes were seen in the OCT scans. Latencies over 100 milliseconds and reduced amplitudes of P100 were found in the PRVEP (p < 0.05). The reduced amplitude of the b wave at the ffERG, of the P50 at the PERG and of the P1 wave at the mfERG results (p < 0.05) suggested that the outer retina was involved. Significant negative correlations among blood mercury levels, VA, and ffERG were observed. CONCLUSIONS: In this case series, showed that acute exposure to mercury vapor had a hazardous effect on the visual system. Although neurologic and visual pathway involvement was clearly demonstrated, the differences found compared to control support the existence of a direct functional retinal damage and participation in impaired vision in mercury poisoning.