Mercury (Hg)-contaminated soil poses a significant threat to the environment and human health. Hg-resistant microorganisms have the ability to survive under the stress of inorganic and organic Hg and effectively reduce Hg levels and toxicity. Compared to physical and chemical remediation methods, microbial remediation technologies have garnered increasing attention in recent years due to their lower cost, remarkable efficacy, and minimal environmental impact. This paper systematically elucidates the molecular mechanisms of Hg resistance in microbes, with a focus on their potential applications in phytoremediation of Hg-contaminated soils through plant-microbe interactions. Furthermore, it highlights the critical role of microbes in enhancing the effectiveness of transgenic plants for Hg remediation, aiming to provide a theoretical foundation and scientific basis for the bioremediation of Hg-contaminated soils.
Mercury/toxicity* ; Biodegradation, Environmental ; Soil Pollutants/isolation & purification* ; Soil Microbiology ; Plants, Genetically Modified/metabolism* ; Bacteria/genetics*

Mercury is a global pollutant. Children are vulnerable to environmental toxicants. Seafood consumption is a major source of methylmercury exposure. In order to ascertain children's mercury exposure levels and study their relationship with seafood consumption, we conducted a cross-sectional study among preschool children in Shanghai. According to our data, the geometric mean of the mercury levels in children's hair was 191.9 (95% CI: 181.8, 202.4) μg/kg. These results indicate that high income may be a predictor of elevated mercury levels in children's hair. Intake of marine fish, especially tuna and pomfret, was documented in our study and found to increase the risk of high mercury levels. Frequency of fish consumption was positively related with hair mercury levels. Our study is the first to provide baseline data for hair mercury concentration among preschool children in Shanghai.
Child, Preschool ; China ; Food Contamination ; Hair ; chemistry ; Humans ; Mercury ; chemistry ; metabolism ; Seafood ; analysis ; Socioeconomic Factors ; Water Pollutants, Chemical ; chemistry

α-HgS is the main component of traditional Chinese medicine cinnabar, while β-HgS is the main component of Tibetan medicine Zuotai. However, there was no comparative study on the dissolution and absorption in gastrointestinal tract and bioaccumulation in organs of mercury in Cinnabar, Zuotai, α-HgS and β-HgS. In this study, the dissolution process of the four compounds in the human gastrointestinal tract was simulated to determine the mercury dissolutions and compare the mercury dissolution of different medicines and the dissolution-promoting capacity of different solutions. To explore the absorption and bioaccumulation of cinnabar and Zuotai in organisms, mice were orally administered with clinical equivalent doses cinnabar and Zuotai. Meanwhile, a group of mice was given α-HgS and β-HgS with the equivalent mercury with cinnabar, while another group was given β-HgS and HgCl2 with the equivalent mercury with Zuotai. The mercury absorption and bioaccumulation capacities of different medicines in mice and their mercury bioaccumulation in different tissues and organs were compared. The experimental results showed a high mercury dissolutions of Zuotai in artificial gastrointestinal fluid, which was followed by β-HgS, cinnabar and α-HgS. As for the mercury absorption and bioaccumulation in mice, HgCl2 was the highest, β-HgS was the next, and a-HgS was slightly higher than cinnabar. The organs with the mercury bioaccumulation from high to low were kidney, liver and brain. This study is close to clinical practices and can provide reference for the clinical safe medication as well as a study model for the safety evaluation on heavy metal-containing medicines by observing the mercury dissolution, absorption, distribution and accumulation of mercury-containing medicines cinnabar and zuotai.
Animals ; Brain ; metabolism ; Drugs, Chinese Herbal ; chemistry ; pharmacokinetics ; Gastrointestinal Tract ; metabolism ; Kidney ; metabolism ; Liver ; metabolism ; Male ; Mercury ; chemistry ; pharmacokinetics ; Mercury Compounds ; chemistry ; pharmacokinetics ; Mice ; Solubility

OBJECTIVETo study the effect of Zhusha Anshen pill, cinnabar, HgS, HgCl2 and MeHg on the gene expression of renal transporters in mice.

METHODHealthy male mice were given equivalent physiological saline, Zhusha Anshen pill (1.8 g · kg(-1), containing 0.17 g · kg(-1) of mercury), cinnabar (0.2 g · kg(-1), containing 1.7 g · kg(-1) of mercury), high dose cinnabar (2 g · kg(-1), containing 1.7 g · kg(-1) of mercury), HgS (0.2 g · kg(-1), containing 0.17 g · kg(-1) of mercury), HgCl2 (0.032 g · kg(-1), containing 0. 024 g · kg(-1) of mercury), MeHg (0.026 g · kg(-1), containing 0.024 g · kg(-1) of mercury), once daily, for 30 d, measuring body mass gain. 30 days later, the mice were sacrificed. The mercury accumulation in kidneys was detected with atomic fluorescence spectrometer. Expressions of Oat1, Oat2, Oat3, Mrp2, Mrp4, Urat1 were detected with RT-PCR.

RESULTCompared with the normal control group, a significant accumulation of Hg in kidney in HgCl2 and MeHg groups was observed (P <0.05), but these changes were not found in other groups. Compared with normal control group, mRNA expressions of Oat1 and Oat2 were evidently lower in HgCl2 and MeHg groups, but mRNA expressions of Mrp2 were apparently higher in HgCl2 group (P <0.05), mRNA expression of Mrp4 was significant higher in HgCl2 and MeHg groups, and mRNA expression of Urat1 was apparently lower in MeHg group.

CONCLUSIONHgCl2 and MeHg groups show significant difference from the normal group in mercury accumulation in kidneys and gene expression of kidney transporters, but with no difference between other groups and the normal group. Compared with HgCl2 and MeHg, cinnabar and its compounds could cause lower renal toxicity to mice.

Animals ; Carrier Proteins ; genetics ; Drugs, Chinese Herbal ; toxicity ; Gene Expression ; drug effects ; Kidney ; drug effects ; metabolism ; Male ; Mercuric Chloride ; toxicity ; Mercury Compounds ; toxicity ; Methylmercury Compounds ; toxicity ; Mice ; Multidrug Resistance-Associated Proteins ; genetics ; Organic Anion Transport Protein 1 ; genetics ; Organic Anion Transporters, Sodium-Independent ; genetics

Methylmercury is a hazardous substance that is of interest with regard to environmental health, as inorganic mercury circulating in the general environment is dissolved into freshwater and seawater, condensed through the food chain, ingested by humans, and consequently affects human health. Recently, there has been much interest and discussion regarding the toxicity of methylmercury, the correlation with fish and shellfish intake, and methods of long-term management of the human health effects of methylmercury. What effects chronic exposure to a low concentration of methylmercury has on human health remains controversial. Although the possibility of methylmercury poisoning the heart and blood vessel system, the reproductive system, and the immune system is continuously raised and discussed, and the carcinogenicity of methylmercury is also under discussion, a clear conclusion regarding the human health effects according to exposure level has not yet been drawn. The Joint FAO/WHO Expert Committee on Food Additives proposed to prepare additional fish and shellfish intake recommendations for consumers based on the quantified evaluation of the hazardousness of methylmercury contained in fish and shellfish, methylmercury management in the Korea has not yet caught up with this international trend. Currently, the methylmercury exposure level of Koreans is known to be very high. The starting point of methylmercury exposure management is inorganic mercury in the general environment, but food intake through methylation is the main exposure source. Along with efforts to reduce mercury in the general environment, food intake management should be undertaken to reduce the human exposure to methylmercury in Korea.
Animals ; *Environmental Exposure ; Fishes/metabolism ; Food Chain ; Humans ; Mercury Poisoning, Nervous System/etiology ; Methylmercury Compounds/chemistry/*metabolism/toxicity ; Neurons/drug effects ; Oxidative Stress/drug effects ; Public Health ; Reproduction/drug effects ; Thymocytes/cytology/drug effects

Mercury is a toxic and non-essential metal in the human body. Mercury is ubiquitously distributed in the environment, present in natural products, and exists extensively in items encountered in daily life. There are three forms of mercury, i.e., elemental (or metallic) mercury, inorganic mercury compounds, and organic mercury compounds. This review examines the toxicity of elemental mercury and inorganic mercury compounds. Inorganic mercury compounds are water soluble with a bioavailability of 7% to 15% after ingestion; they are also irritants and cause gastrointestinal symptoms. Upon entering the body, inorganic mercury compounds are accumulated mainly in the kidneys and produce kidney damage. In contrast, human exposure to elemental mercury is mainly by inhalation, followed by rapid absorption and distribution in all major organs. Elemental mercury from ingestion is poorly absorbed with a bioavailability of less than 0.01%. The primary target organs of elemental mercury are the brain and kidney. Elemental mercury is lipid soluble and can cross the blood-brain barrier, while inorganic mercury compounds are not lipid soluble, rendering them unable to cross the blood-brain barrier. Elemental mercury may also enter the brain from the nasal cavity through the olfactory pathway. The blood mercury is a useful biomarker after short-term and high-level exposure, whereas the urine mercury is the ideal biomarker for long-term exposure to both elemental and inorganic mercury, and also as a good indicator of body burden. This review discusses the common sources of mercury exposure, skin lightening products containing mercury and mercury release from dental amalgam filling, two issues that happen in daily life, bear significant public health importance, and yet undergo extensive debate on their safety.
Biological Availability ; Biological Markers/blood/urine ; Blood-Brain Barrier/metabolism ; Body Burden ; Dental Amalgam/chemistry/metabolism ; *Environmental Exposure ; Humans ; Mercury/chemistry/*metabolism ; Mercury Compounds/chemistry/*metabolism ; Skin Lightening Preparations/chemistry/metabolism

Mercury is emitted to the atmosphere from various natural and anthropogenic sources, and degrades with difficulty in the environment. Mercury exists as various species, mainly elemental (Hg0) and divalent (Hg2+) mercury depending on its oxidation states in air and water. Mercury emitted to the atmosphere can be deposited into aqueous environments by wet and dry depositions, and some can be re-emitted into the atmosphere. The deposited mercury species, mainly Hg2+, can react with various organic compounds in water and sediment by biotic reactions mediated by sulfur-reducing bacteria, and abiotic reactions mediated by sunlight photolysis, resulting in conversion into organic mercury such as methylmercury (MeHg). MeHg can be bioaccumulated through the food web in the ecosystem, finally exposing humans who consume fish. For a better understanding of how humans are exposed to mercury in the environment, this review paper summarizes the mechanisms of emission, fate and transport, speciation chemistry, bioaccumulation, levels of contamination in environmental media, and finally exposure assessment of humans.
Air Pollutants/chemistry/metabolism ; *Environmental Exposure ; Environmental Remediation ; Food Chain ; Humans ; Mercury/chemistry/*metabolism ; Methylmercury Compounds/chemistry/metabolism ; Photolysis ; Sulfur-Reducing Bacteria/metabolism ; Water Pollutants, Chemical/metabolism

Mercury-containing preparations are widely used in surgery department of traditional Chinese medicine and have made remarkable achievements. But they are toxic to human kidney, nerve, immune, etc. Smilacis Glabrae Rhizoma is sweet, tasteless and neutral in nature and able to enter liver and stomach channels and detoxify mercury poisoning. This article summarizes the mercury poisoning and the detoxification effect of Smilacis Glabrae Rhizoma in ancient records, pharmaceutical studies and clinical application, in order to provide ideas and methods for the safe use of mercury-containing preparations in surgery department of traditional Chinese medicine.
Drugs, Chinese Herbal ; therapeutic use ; Humans ; Inactivation, Metabolic ; Liliaceae ; chemistry ; Liver ; drug effects ; metabolism ; Medicine, Chinese Traditional ; Mercury Compounds ; adverse effects ; pharmacokinetics ; therapeutic use ; Mercury Poisoning ; prevention & control ; Plants, Medicinal ; chemistry ; Rhizome ; chemistry ; Stomach ; drug effects ; metabolism

OBJECTIVETo study the effects of Zhuhong ointment on accumulation in the body of mercury and the pathological morphology changes of kidney, via the measurement of related indicators of the skin-impaired model rat.

METHODEighty-eight SD rats were randomly divided into the impairment control group, and high-, middle-, low-dose Zhuhong ointment groups. Each group was treated by corresponding methods for 4 weeks, and recovering for 4 weeks. Urinary potein (PRO), pH, Beta N-acetyl aminoglycosidase enzymes (NAG) and beta2-microglobulin (beta2-MG) contents in urine were taken as monitoring indexes, blood urea nitrogen (BUN) and serum creatinine (SCr) in blood and the levels of mercury in urine, blood and kidney were tested, and the pathological morphology changes of kidney were observed.

RESULTAfter treatment for 4 weeks, compared with impairment control group, the levels of mercury in urine, blood and kidney in every dose group increased significantly (P < 0.01). And the relation exists between toxicity and dose on Zhuhong ointment. After recovery for 4 weeks, the levels of mercury in urine and blood in every dose group restore normal, while the level of mercury in kidney in high- dose group still increased (P < 0.01). The level of NAG increased only in high-dose group. There was no significant difference in NAG contents between Zhuhong ointment groups and the impairment control group (P < 0.05).

CONCLUSIONExcess using Zhuhong ointment repeatedly may lead to accumulation of mercury and pathological morphology changes of kidney. So the levels of mercury in the body and related indicators of renal functions should be tested in clinical when long-term using Zhuhong ointment.

Acetylglucosaminidase ; drug effects ; urine ; Animals ; Blood Urea Nitrogen ; Creatinine ; blood ; Disease Models, Animal ; Drugs, Chinese Herbal ; pharmacology ; toxicity ; Female ; Hydrogen-Ion Concentration ; drug effects ; Kidney ; drug effects ; enzymology ; metabolism ; pathology ; Male ; Mercury ; blood ; metabolism ; urine ; Ointments ; Random Allocation ; Rats ; Rats, Sprague-Dawley ; Retinol-Binding Proteins ; drug effects ; urine ; Skin ; drug effects ; injuries ; Time Factors ; beta 2-Microglobulin ; urine

OBJECTIVETo study the effect of repeated administration of Zhuhong ointment on renal antioxidant capability of ulcerous skin in rats, in order to further discuss the mechanism of mercury contained in Zhuhong ointment on the antioxidant capability of kidney in skin ulcer rats.

METHODEighty SD rats were randomly divided into eight groups: Zhuhong ointment A, B, C, D, E (1.219, 0.609, 0.305, 0.152, 0.76 g x kg(-1)) groups, the vaseline group, the ulcer model group and the impairment control group. The levels of NAG and RBP of toxicity for early kidney tubular injury and T-AOC, SOD, GSH-PX and GSH in kidney were determined after consecutive administration for 14 days.

RESULTCompared with ulcer model group, the levels of RBP in groups A, B, C and D increased, while the levels of NAG increased only in the group A. The level of T-AOC increased in groups A, B and C. The level of T-SOD increased in the group E, while it dropped down greatly in the group A. The level of GSH-PX increased in groups A, B and C. The content of GSH increased in every dose groups.

CONCLUSIONAntioxidant capacity in rats can be increased in a reasonable dose of Zhuhong ointment, but some antioxidant activity can be notably inhibited by with the increase of dose.

Acetylglucosaminidase ; drug effects ; urine ; Animals ; Antioxidants ; analysis ; metabolism ; Disease Models, Animal ; Dose-Response Relationship, Drug ; Drugs, Chinese Herbal ; administration & dosage ; pharmacology ; toxicity ; Glutathione ; drug effects ; metabolism ; Glutathione Peroxidase ; drug effects ; metabolism ; Kidney Tubules ; drug effects ; injuries ; metabolism ; Male ; Mercury ; metabolism ; Ointments ; Random Allocation ; Rats ; Rats, Sprague-Dawley ; Retinol-Binding Proteins ; drug effects ; urine ; Skin Ulcer ; metabolism ; microbiology ; Specific Pathogen-Free Organisms ; Staphylococcal Skin Infections ; metabolism ; Superoxide Dismutase ; drug effects ; metabolism ; Time Factors