ABSTRACT
Objective@#To evaluate health risks of five heavy metals in drinking water of rural schools in Henan Province, so as to provide scientific basis for drinking water safety in rural schools.@*Methods@#Totally 1 269 drinking water samples were collected and analyzed for five heavy metals (As, Cd, Cr 6+ , Pb, Hg) concentration in 106 cities and counties of Henan Province, and its spatial distribution characteristics were explored by geographic information system (GIS). Risk assessment method recommended by the United States Environmental Protection Agency (U.S. EPA) was applied to evaluate health risks from five heavy metals through oral ingestion.@*Results@#The qualified rate of As concentration was 100%, and the qualified rates of Cd, Cr 6+ , Pb and Hg were 99.9% , 99.9%, 99.5%, 99.6%. The highest carcinogenic risk was As (3.05×10 -5 ), followed by Cr 6+ (2.73×10 -5 ), and the highest non carcinogenic risk was As (0.158 3), followed by Pb(0.041 7). The carcinogenic risk and non carcinogenic risk were all higher in girls than boys. The carcinogenic and non carcinogenic risks were differences in different regions( P <0.05).@*Conclusion@#Health risks of five heavy metals in drinking water for rural schools in Henan Province were within the acceptable risk level recommended by EPA. As, Cr 6+ and Pb were the main health risk factors in drinking water, and that might impact negatively the healthy growth of primary and middle school students. These should be future efforts of drinking water safety management.
ABSTRACT
Background: The presence of toxic metals in human populations is strongly associated with chronic diseases. Aim: To determine levels of lead, chromium, cadmium, mercury and inorganic arsenic (AsIn) in the general population aged over 5 years in Antofagasta, Chile. Material and Methods: People living in Urban Antofagasta for at least five years were considered eligible. Biological samples were obtained to measure heavy metals. Results: One thousand two hundred three participants with a median age of 43 years (656 women) were studied. Their mean time of residence in the city was 30 years, and 52% smoked. Eight percent of the adult population and 12% of children had AsIn values above 35 µg/L, while 75% of the population had levels below 21.9 µg/L. The other metals were below the risk levels defined by the health authority (10 µg/L for chromium, 10 µg/L for mercury, 2 µg/L for cadmium, 5 and 10 μg/dL for blood lead for children and adults, respectively). The factors associated with high levels of AsIn in adults were male sex, living more than 200 meters from monitoring points, and low schooling. In children, the associated variables were high intake of seafood products and having a caregiver with less than 8 years of schooling. Contrary to expectations, the greatest risk of presenting altered levels of the metals occurred in the population living more than 500 meters from the identified risk sources (90% of the population). Conclusions: The findings of this study suggest that all potential sources of exposure to AsIn should be evaluated, and surveillance actions should be established to reduce involuntary exposure to this metalloid.
Subject(s)
Humans , Male , Female , Adult , Metals, Heavy/urine , Lead/blood , Chile/epidemiology , Environmental MonitoringABSTRACT
RESUMEN El plomo (Pb) es un metal pesado cuyas características físico-químicas lo convierten en un contaminante ambiental persistente, bioacumulable y de alta toxicidad. La biorremediación surge como una alternativa con múltiples ventajas en comparación con los tratamientos convencionales para remover contaminantes como metales pesados de aguas residuales, basándose en las capacidades de tolerancia y mecanismos de resistencia de los microorganismos. Con el fin de conocer la tolerancia de Pseudomonas spp. al plomo presente en aguas contaminadas, se obtuvieron cuatro aislados nativos, procedentes de aguas residuales colectadas en el río del Valle de Aburrá (zona norte), los cuales se caracterizaron bioquímicamente. Se realizaron bioensayos de tolerancia en diferentes concentraciones de plomo por difusión en agar, como prueba tamiz, y determinación de la concentración mínima inhibitoria, determinando la viabilidad del microorganismo en cada exposición. No se presentó diferencia significativa para la tolerancia al plomo entre los aislados, identificados bioquímicamente como Pseudomonas aeruginosa, ni entre las diferentes concentraciones de plomo a las cuales fueron expuestos los aislados. A partir de estos resultados, se discute a cerca de los mecanismos reportados por diferentes autores, mediante los cuales Pseudomonas spp. puede actuar en presencia de Plomo. De esta manera, se concluye que los aislados de Pseudomonas spp. presentan mecanismos de tolerancia y/o resistencia hasta concentraciones de 2500 mg/L en presencia de nitrato de plomo, como potenciales agentes que pueden integrarse en procesos que impulsan nuevas tecnologías de biorremediación.
ABSTRACT Lead (Pb) is a heavy metal whose physicochemical characteristics make it a persistent environmental pollutant, bioaccumulable and highly toxic. Bioremediation emerges as an alternative with multiple advantages compared to conventional treatments to remove contaminants such as heavy metals from wastewater, based on the tolerance capacities and/or resistance mechanisms of microorganisms. In order to know the tolerance of Pseudomonas spp. to the lead present in contaminated waters, four native isolates were obtained, coming from wastewater collected in the north from Aburrá Valley River, which were characterized biochemically. Tolerance bioassay was carried out in different concentrations of lead by agar diffusion, as a screening test, and determination of the minimum inhibitory concentration, determining the viability of the microorganism in each exposure. There was no significant difference for lead tolerance between the isolates, identified biochemically as Pseudomonas aeruginosa, nor between the different concentrations of lead to which the isolates were exposed. From these results, we discuss about the mechanisms reported by different authors, by means of which Pseudomonas spp. can act in the presence of lead. In this way, it is concluded that the isolates of Pseudomonas spp. they present tolerance and/or resistance mechanisms up to 2500 mg/L in the presence of lead nitrate, as potential agents that can be integrated into processes that promote new bioremediation technologies.
ABSTRACT
Objective: To assess the levels of nickel and chromium ions in hair and Gingival Crevicular Fluid (GCF) of orthodontic patients and to evaluate the corrosion of orthodontic bracket surfaces. Material and Methods: Nickel and chromium ion concentrations were measured in hair and GCF of 15 patients (9 females and 6 males, aged 16-28 years old) who had fixed orthodontic treatment using atomic absorption spectroscopy. The samples were taken before treatment (baseline), 4, 8, and 16 months later during treatment. Along with ionic sampling, microscopic sampling was done. One of each patient brackets was removed to get 15 brackets per group. Five brackets were taken randomly from each group to be examined under scanning electron microscope (SEM). Data obtained were analyzed using paired t-tests. Results: After 16 months, compared with the baseline, average hair nickel level changed from 0.125 µg/g to 0.956 µg/g with statistically significant difference (p=0.00); average chromium level changed from 0.090 µg/g to 0.295 µg/g but no significant difference (p>0.05); average GCF nickel level changed from 3.335 µg/g to 10.410 µg/g; average chromium level changed from 1.859 µg/g to 9.818 µg/g. Both of these increases were significant (p=0.000). SEM examinations showed that the corrosion on brackets was seen in the fourth month, and more severely visible after 8 and 16 months of uses. Conclusion: After 16 months of treatment, compared with the baseline, the hair nickel level was increased by 7.7 times; while for chromium was by 3.3 times. Gingival crevicular fluid nickel level was increased by 3.1 times and chromium level was by 5.3 times. The longer time of treatment, the more ions released and the more corrosion of brackets will be.
Subject(s)
Humans , Male , Female , Adolescent , Adult , Orthodontics , Longitudinal Studies , Chromium , Dental Etching/methods , Nickel , Indonesia , IonsABSTRACT
Increasing e-waste has become a major problem for global environment and public health. In the process of dismantling and recycling of disordered electronic waste, heavy metals such as lead and brominated flame retardants and organic substances are released into environmental media such as air, soil, dust and water, which is harmful to the health of local residents. Taking an e-waste dismantling area in Guangdong Province as an example, this paper reviews exposure levels of heavy metals and organic matters in e-waste recycling areas in China, as well as the health effects of local residents. Previous studies have found that e-waste recycling activities led to serious environmental pollution and high exposure levels of heavy metals and organic matters in local residents, which has a certain impact on the physiological functions of various human systems. The establishment of a centralized dismantling zone can effectively reduce the load level of various pollutants.
ABSTRACT
Objective@#To evaluate the non-carcinogenic health risk of heavy metals (As, Cd, Cr, Cu, Mn, Pb and Zn) in residential indoor dust for young children around an e-waste dismantling area in South China.@*Methods@#A village around an e-waste dismantling area in South China was selected as a research site in October 2016. Convenience sampling method was used to select 36 houses in the village and 36 dust samples were collected by vacuum cleaner. The concentrations of heavy metals (Cd, Cr, Cu, Mn, Pb and Zn) in each sample were determined and expressed by the average value. Non-carcinogenic health risk assessment was conducted using the US Environmental Protection Agency (EPA) Health Risk Assessment (HRA) model, the American Toxicology and Disease Registry (ATSDR) Target-organ Toxicity Dose (TTD) approach and the ATSDR Binary Weight-of-Evidence (BINWOE) model.@*Results@#The mean ± SD of concentrations of As, Cd, Cr, Cu, Mn, Pb and Zn were (48.90±33.91), (5.95±3.89), (173.57±580.37), (412.71±1 190.00), (612.82±540.70), (297.41±293.22) and (1 052.81±1 156.48) mg/kg, respectively. The HI value of TTD (2.670) and BINWOE (2.933) were higher than the safety threshold of EPA recommended non-carcinogenic health risk. The HI value of TTD and BINWOE were 1.93 and 2.12 times higher than the HI value of HRA (1.386).@*Conclusion@#There was non-carcinogenic health risk of heavy metals (As, Cd, Cr, Cu, Mn, Pb and Zn) via residential indoor dust around the e-waste dismantling area for local children.
ABSTRACT
OBJECTIVES: Heavy metals ingested through the consumption of aquatic products can accumulate in the human body over the long-term and cause various health problems. This study aims to present comprehensive data on the amount of heavy metals found in fish and shellfish in Korea using a systematic review of studies that report on that issue. METHODS: The study used the following databases: PubMed, Korean Studies Information Service System, and Research Information Sharing Service. The search terms for PubMed included fish OR shellfish OR seafood AND mercury OR cadmium OR lead OR heavy metal AND Korea. The search terms for Korean Studies Information Service System and Research Information Sharing Service included eoryu sueun, eoryu kadeumyum, eoryu nab, eoryu jung-geumsog, paeryu sueun, paeryu kadeumyum, paeryu nab, paeryu jung-geumsog, eopaeryu sueun, eopaeryu kadeumyum, eopaeryu nab, and eopaeryu jung-geumsog. RESULTS: A total of 32 articles were selected for review. The total mercury, lead, and cadmium concentrations in fish and shellfish reported in each of the articles are summarized, as are the species of fish and shellfish with relatively high concentrations of heavy metals. Total mercury concentrations tended to be higher in predatory fish species, such as sharks, billfishes, and tuna, while lead and cadmium concentrations tended to be higher in shellfish. CONCLUSION: This paper is the first to report a comprehensive summary of the concentrations of heavy metals in fish and shellfish. This data could be used as evidence to protect Koreans from exposure to heavy metals due to the consumption of highly polluted aquatic products.
Subject(s)
Cadmium , Fishes , Human Body , Information Dissemination , Information Services , Korea , Metals, Heavy , Seafood , Sharks , Shellfish , TunaABSTRACT
BACKGROUND: Despite increasing concern regarding health problems as a result of environmental pollutants, no association of toxic heavy metals with sarcopenia has been demonstrated in the general population. We investigated the association of heavy metals, including lead, mercury and cadmium, with sarcopenia in the Korean population. METHODS: Participants included 344 males and 360 females older than 65 years based on data from the fourth and fifth Korea National Health and Nutritional Examination Surveys. Measurements of blood lead, mercury and cadmium levels were performed. To evaluate the cumulative effect of the three heavy metals, subjects were categorized into quartiles. Sarcopenia was defined according to the criteria for the Asia Working Group for Sarcopenia (AWGS) (SMI<5.4 kg/m2 in females and <7.0 kg/m2 in males). RESULTS: Of 704 elderly persons (344 in males and 360 in females), prevalences of sarcopenia were 26.7% (92/344) in male and 7.5% (27/360) in female. Mean serum levels of lead in sarcopenia group were significantly higher than non-sarcopenia males (P=0.03). After adjustment for confounding factors, odds ratio for sarcopenia were increased with concentration category of lead (P=0.005 and P<0.001), mercury (P=0.001 and P<0.001) and cadmium (P=0.010 and P<0.001) in males and females, respectively. CONCLUSIONS: This study demonstrates that high levels of blood lead, mercury and cadmium increase the prevalence of sarcopenia in both genders of elderly populations.
Subject(s)
Aged , Female , Humans , Male , Asia , Cadmium , Environmental Pollutants , Korea , Metals, Heavy , Odds Ratio , Prevalence , SarcopeniaABSTRACT
ABSTRACT We report two cases of severe thermal burns on the ocular surface and its adnexal appendages that developed secondary to exposure to molten heavy metal with a melting temperature of near-thousand degree Celsius. Despite aggressive intervention and strict monitoring, the profound inflammation caused significant damage to the ocular surface, ending up in an intractable infection with an unfavorable outcome. The heat of the molten metal at impact, the heat-retaining capacity of the heavy metal, the total area of the ocular surface exposed to the molten metal, and the duration of exposure determined the severity of the injury. The unfavorable outcome, despite an intensive treatment, in terms of visual acuity and cosmetic appearance, should be explicitly explained to the patient, and a psychiatrist consultation should be considered if necessary.
RESUMO Relatamos dois casos de queimaduras graves da superfície ocular e seus anexos causadas por exposição à metais pesados derretidos com temperatura de fusão de quase mil graus Celsius. Embora rigorosamente acompanhados, a inflamação intensa causou danos significativos para a superfície ocular, que acabou em uma infecção intratável com um resultado desfavorável. O calor do metal fundido no momento do impacto, a capacidade de retenção de calor do metal pesado, a área total da superfície ocular exposta ao metal fundido e a duração da exposição determinaram a gravidade da lesão que vai ocorrer. O resultado desfavorável, apesar do tratamento intensivo, em relação à acuidade visual e à aparência estética, devem ser claramente explicados ao paciente e uma consulta ao psiquiatra deve ser considerada, se necessário.
Subject(s)
Adult , Humans , Male , Middle Aged , Eye Burns/etiology , Hot Temperature , Metals , Corneal Injuries/etiology , Eye Burns/pathology , Eye Burns/therapy , Trauma Severity Indices , Treatment Outcome , Visual AcuityABSTRACT
Introducción. En Colombia, la minería es una actividad económica importante; sin embargo, genera grandes cantidades de residuos que contienen elementos potencialmente tóxicos, como los metales pesados, que contaminan los ecosistemas y ponen en riesgo la salud humana. La región de La Mojana es una de las zonas más ricas en biodiversidad del planeta y se ha visto sometida a procesos de contaminación muy relacionados con la minería de oro que se desarrolla en sus alrededores. Objetivo. Evaluar la genotoxicidad en una población expuesta a residuos de metales pesados en la región de La Mojana. Materiales y métodos. Se evaluaron los efectos genotóxicos y su relación con la concentración de metales pesados (mercurio, cadmio y plomo) en muestras de sangre de la población expuesta y el grupo de control. El grupo expuesto lo conformaron habitantes de los municipios de Guaranda, Sucre, Majagual y San Marcos; en el grupo de control se incluyó a habitantes del municipio de Montería. Se determinó el daño en el ADN mediante el ensayo cometa en condiciones alcalinas. Las concentraciones de mercurio se establecieron mediante espectrometría de absorción atómica con vapor frío, en tanto que las de cadmio y plomo se determinaron por espectrometría de absorción atómica en horno de grafito. Resultados. Las concentraciones de los metales sobrepasaron los límites permitidos por la Organización Mundial de la Salud. Se evidenciaron efectos genotóxicos posiblemente asociados a la presencia de los metales en la sangre. Se encontraron asociaciones significativas (p<0,05) entre la presencia de mercurio y de cadmio, y el daño en el ADN. Conclusión. Estos resultados sugieren que el daño genético registrado en pobladores de la región de La Mojana, Colombia, puede estar asociado a la presencia de los metales estudiados en las muestras de sangre.
Introduction: Mining is an economically important activity in Colombia which generates large quantities of residues containing potentially toxic elements such as heavy metals. These contaminate ecosystems and place human health at risk. La Mojana lies within one of the most biodiversity-rich zones on Earth and has been subjected to processes of contamination closely related to gold mining activities in the surrounding areas. Objective: To evaluate genotoxicity in the population of La Mojana region exposed to heavy metals. Materials and methods: Genotoxic effects and their relationship with concentrations of heavy metals (mercury, cadmium and lead) in blood were evaluated among an exposed population and a control group. The exposed group comprised inhabitants of the municipalities of Guaranda, Sucre, Majagual and San Marcos; inhabitants of the municipality of Montería were chosen as a control group. DNA damage was determined using the alkaline comet assay. Concentrations of mercury were determined by cold vapor atomic absorption spectrometry, and those of cadmium and lead by graphite furnace atomic absorption spectrometry. Results: Concentrations of the heavy metals exceeded the limits permitted by the World Health Organization. Genotoxic effects were found in the exposed population, possibly associated with the presence of these metals in blood. Significant associations (p<0.05) were found between mercury and cadmium levels and damage to DNA. Conclusion: These results suggest that the genetic damage recorded among inhabitants of the region of La Mojana, Colombia, may be associated with the presence of heavy metals in the blood.
Subject(s)
Adolescent , Adult , Female , Humans , Male , Middle Aged , Young Adult , Environmental Exposure , Metals, Heavy/toxicity , Mutagens/toxicity , Colombia , Cross-Sectional Studies , Cadmium/blood , Lead/blood , Mercury/bloodABSTRACT
Objetivos. Determinar las concentraciones de material particulado (PM10) y metales pesados en el ambiente, así como en población aledaña al proyecto Las Bambas luego de cinco años de exploración minera. Materiales y métodos. Estudio comparativo de corte transversal realizado en tres distritos del área de influencia del proyecto Las Bambas en la región Apurímac, Perú. Se obtuvo muestras de agua, aire y suelo para determinar las concentraciones de PM10 y metales pesados. Se tomó muestras de sangre y orina a 310 pobladores para evaluar niveles de plomo, cadmio, arsénico y mercurio. Los resultados se compararon con los obtenidos el año 2005. Resultados. Concentraciones ambientales de PM10 y metales pesados no sobrepasaron los valores referenciales establecidos. La calidad de agua de consumo y suelo no se encuentra alterada. Para el año 2010 comparado con los valores hallados el 2005, los niveles promedio de cadmio y mercurio en orina se incrementaron significativamente en la población del distrito de Chalhuahuacho (2,4 + 0,8 y 2,6 + 0,4), el Progreso (2,6 + 1,1 y 2,9 + 1,3) y Haquira (3,2 + 1,2 y 2,6 + 0,9). Los valores de cadmio superaron los límites permisibles. Conclusiones. Luego de cinco años de actividad de exploración minera, no se han visto afectadas las características ambientales de la zonas de influencia del proyecto minero Las Bambas, sin embargo, se observan cambios en los niveles de cadmio en orina y en el porcentaje de personas que lo presentan.
Objectives. Determine particulate matter (PM10) and heavy metals concentrations in the environment, as well as in surrounding communities of the Las Bambas project after five years of mineral exploration. Materials and methods. A comparative cross-sectional study was conducted in three districts in the area of influence of the Las Bambas project in Apurimac, Peru. Samples of water, air and soil were obtained to determine the concentrations of PM10 and heavy metals. Blood and urine samples were taken from 310 villagers to evaluate levels of lead, cadmium, arsenic and mercury. Results were compared with those obtained in 2005. Results. Environmental concentrations of PM10 and heavy metals did not exceed the established reference values. The quality of drinking water and soil was not altered. Compared to the values found in 2005, the 2010 average levels of cadmium and mercury in urine increased significantly in the population of the districts of Chalhuahuacho (2.4 + 0.8 and 2.6 + 0.4), El Progreso (2.6 + 1.1 and 2.9 + 1.3) and Haquira (3.2 + 1.2 and 2.6 + 0.9). Cadmium values exceeded permissible limits. Conclusions. After five years of mineral exploration activity, environmental characteristics of the areas of influence of the Las Bambas mining project, have not been affected. However, changes are observed in the levels and percentage of people with cadmium in their urine.
Subject(s)
Humans , Male , Adolescent , Adult , Female , Child, Preschool , Child , Particulate Matter , Metals, Heavy , Mining , Epidemiology, Descriptive , Longitudinal Studies , PeruABSTRACT
A cidade de São Luís, capital do estado do Maranhão, possui um sistema ineficiente de tratamento de seus efluentes e boa parte deles é lançada nos rios ou diretamente nas praias. Este trabalho teve como objetivo avaliar o grau de resistência aos metais pesados de 39 cepas de E.coli, isoladas da água de praias da cidade, além de sua suscetibilidade a antibióticos e sua capacidade de produzir biofilme. A análise da resistência aos metais pesados foi realizada pelo método de diluições sucessivas nas concentrações de 1 a 16mM.O teste de sensibilidade, ou antibiograma, foi executado pelo método de difusão em disco, utilizando-se os seguintes antibióticos: Aztreonam, Imipenem, Cefalotina, Ampicilina/Sulbactam, Gentamicina, Ampicilina, Cefuroxima sódica, Amoxicilina, Piperacilina+Tazobactam (TZP), Trimetoprim-Sulfametoxazol (SXT) e Amoxicilina+Ácido Clavulânico (AMC). Para detecção de biofilme nas cepas de E. coli, foram utilizadas as técnicas de Ágar Vermelho Congo (AVC) e Espectrofotometria (ESP). Os resultados mostraram 2 cepas tolerantes a concentrações de Hg a 1mM, 9 cepas resistentes ao Cu e Cd a 4mM e 12 ao Ni a 4mM. O exame de susceptibilidade aos antibióticos mostrou os seguintes percentuais de resistência das amostras: 15 por cento a ATM, 95 por cento a KF, 85 por cento a ASB, 85 por cento a CN, 87 por cento a AMP, 13 por cento a CXM, 5 por cento a TZP, 74 por cento a SXT e 18 por cento a AMC. Quanto à produção de biofilme, 20 por cento apresentaram elevada produção, 36 por cento fraca produção e 44 por cento não produziram. Pela técnica de espectrofotometria, somente 1 cepa (2,5 por cento) revelou-se produtora moderada de biofilme, 5 (12,5 por cento) foram classificadas como não produtoras e as demais, 34 (85 por cento), como fracas produtoras. A presença de bactérias com múltiplos perfis de resistência nas praias de São Luís pode representar riscos para a saúde pública e causar alterações diretas na ecologia das comunidades de micro-organismos marinhos.
The city of São Luís, located in the State of Maranhão has inefficient treatment of sewage, which isreleased into the rivers or directly on the beaches. This study evaluated the resistance of 39 strainsof Escherichia coli to Cu, Ni, Cd and Hg, their susceptibility to antibiotics and ability for biofilmproduction. Samples were collected from the beaches of Ponta DAreia, São Marcos, Calhau andOlho dÁgua. The antibiotic susceptibility tests were performed by the disk diffusion method withthe following antibiotics: Aztreonam (ATM), Imipenem (IMP), Cephalothin (KF), Ampicillin /Sulbactam (ASB), Gentamicin (CN), Ampicillin (AMP), Cefuroxime sodium (CXM), Amoxicillin(AML), Piperacillin Tazobactam (TZP), Trimethoprim-sulfamethoxazole (SXT) and Amoxicillin+ clavulanic acid (AMC). The detection of biofilm production was performed using Congo RedAgar (CRA) and spectrophotometry (ESP). The results showed 2 strains were Hg tolerant (1mM), 9 strains resistant to Cu and Cd (4 mM) and 12 strains resistant to Ni (4 mM). The antibioticsusceptibility tests showed resistance to ATM (15 percent of samples), KF (95 percent), BSA (85 percent), CN (5 percent),AMP (87 percent), CXM (13 percent), TZP (5 percent), SXT (74 percent) and AMC (18 percent). For the synthesis of biofilm inCRA 20 percent showed strong production, 36 percent low and 44 percent did not produce. By spectrophotometryonly 1 (2.5 percent) proved to be a moderate biofilm producer, 5 (12.5 percent) were classified as non-producersand the other 34 (85 percent) weak producers. The presence of bacteria with antimicrobial and heavy metalresistance profiles, and production of biofilms represents a public health risk and cause of directchanges in ecological communities of marine microorganisms.
Subject(s)
Biofilms , Coliforms , Escherichia coli , Metals, Heavy , Microbial Sensitivity TestsABSTRACT
Objective To know automobile exhaust pollution and population exposure to automobile exhaust in Taiyuan,and to provide the basis for controlling automobile exhaust pollution.Methods Two different automobile pollution areas(A and B) were selected as the monitoring sites,the continue sampling was carried out for one week from March to April in 2008.The concentration of PM2.5 was determined by mass method,the inorganic elements in PM2.5 were extracted by Soxhlet method, arsenic and mercury were measured by atomic fluorescent spectrophotometer(AFS),the other metal elements were measured by atomic absorption spectrophotometer.The concentration of NO_x was detected by Saltzman method,the concentration of CO was measured by non-dispersive infrared absorption method.Results At crossroad A,daily average concentration of PM2.5 was 1.604 mg/m~3,which was significantly higher than that at crossroad B(0.64 rag/m~3),P
ABSTRACT
Objective To analyze the concentrations and sources of heavy metals in the soils in city parks,so as to improve the city ecological environment quality and protect the health of people.Methods In December 2007,the distribution characteristics and concentrations of heavy metals(Hg,Cd,Pb,Cu,Zn,Ni,Cr,As)were investigated by ICP-AES and mercury analyzer after the soil samples were collected from six urban parks in Pudong,Shanghai.Results The results showed that the ranges of concentration were 21.08-69.31 mg/kg for Cu,41.87-91.71 mg/kg for Pb,104.65-213.83 mg/kg for Zn,84.63-894.28 mg/kg for Cr,0.15-0.26 mg/kg for Cd,19.14-25.32 mg/kg for As,0.02-0.55 mg/kg for Hg,39.30-454.36 mg/kg for Ni,which indicated that all heavy metals,but Cd had been accumulated in varying degree compared with the soil background contents of metal elements in Shanghai. Conclusion Based on the assessment with the single contamination index,Ni and Cr is relatively in a high level of the pollution in Park 1,while the other heavy metals are in a lower risk.According to the comprehensive contamination indexes,the heavy metals pollution in Park 1 belongs to a high grade,while the other parks are in little pollution level.
ABSTRACT
0.05).In 25.28% of the population in the Second Songhua River region,the hair Hg content exceeded 1 mg/kg.In 21.85% and 16.67% of the population of Wujiazhan town and Songyuan city,the hair Hg content exceeded 1 mg/kg.Conclusion In the investigated area,the level of hair mercury shows a downtrend,but there still is health risk from mercury exposure.
ABSTRACT
Objective To know the blood lead level among twins in Ji’ning,Shandong province,China and to assess the genetic and environmental influence on blood lead level of children. Methods A total of 144 pairs of same sex twins aged 6-14 years were randomly selected in June,2008,and their blood lead level was determined and assessed into three groups,namely the relatively safe group (blood lead level
ABSTRACT
Objective To study the learning and memory abilities together with the morphological changes in astrocyte and neuron in the hippocampal CA3 area in mice induced by chronic cadmium exposure. Methods Twenty Kunming mice aged 4-5 months were selected by Y-maze and randomly divided into two groups. The cadmium exposed group treated with cadmium (CdCl2,2 mg/kg) by subcutaneous injection,twice a week for 3 consecutive months,and the normal control group were injected with the equal dose of saline. The learning and memory abilities were detected by Y-maze after 3 months of treatment. The structure of astrocytes and neurons in CA3 area of hippocampus were observed under light microscope,and the quantitatively analysis was performed by cell morphometric technique. Results Compared with the control group,learning and memory capacity determined by Y-maze test in the cadmium exposed group were lower (P
ABSTRACT
Objective To study the protective effect of cerium on changes of MDA content and DNA damage induced by cadmium in loach liver.Methods The loaches were randomly divided into control group and low (0.025 mg/L),moderate(0.25 mg/L),high(2.5 mg/L)Cd~(2+) exposed group and low(0.025 mg/L Cd~(2+)+0.025 Ce~(3+)),moderate(0.25 mg/L Cd~(2+)+0.25 mg/L Ce~(3+)),high (2.5 mg/L Cd~(2+)+2.5 mg/L Ce~(3+))CdE~(2+)+Ce~(3+) exposed group,the MDA content in loach liver was determined at 1d,2d,3d,5d,7d and 10 d of exposure with the method of TBA,the MDA damage in loach liver was detected at 7 d with the method of agarose gel electrophoresis.Results The MDA content of low Cd~(2+) exposed group was higher than that in the control at ld and 2 d (P
ABSTRACT
Objective To analyze the concentration of heavy metal elements, C, N and H in PM2.5 in the atmosphere in Hangzhou. Methods Midflow samplers were used to collect the samples in Hangzhou city, the element analyzer and microwave digestion ICP-MS were applied to test the samples. Results The average concentrations of N, C, H were 13.9-14.7, 30.3-30.8 and 7.9-8.9 ?g/m3 respectively in the central and northern east areas. The average mass percent values for the three elements(N、C、H) in the city were 12.8%, 27.8% and 8.1% respectively. The average ratios of total inorganic nitrogen to total organic nitrogen (IN/ON) and total organic hydrogen to total inorganic hydrogen (OH/IH) varied in the range of 2.2-3.5 and 3.5-3.6. Eleven elements showed a higher concentration in PM2.5, in which the values of Zn, Pb, Cu and Mn were all more than 200-11 500 mg/kg and the values of Cr, Ni, Se, Mo, Cd and Sb were 17-108 mg/kg, and that was only 6-8 mg/kg for Ag. The levels of average mass percent of all the metal elements were 1.7%-2.0%. Conclusion Carbon is one of important components in PM2.5 in Hangzhou. N and H exist mainly in the form of inorganic and organic compounds respectively. Zn, Pb, Cu, Mn are major heavy metal elements in PM2.5.
ABSTRACT
As a kind of heavy metal, cadmium has the toxicity to multiple organs and tissues. Much progress has been made in the toxicological research, especially in the toxicity to the reproductive system. The recent researches on the toxicity on Cd, the toxicological mechanism and the preventive methods of cadmium poisoning were reviewed in the present paper.