heavy metals

Summary

Summary: Metals with high specific gravity, typically larger than 5. They have complex spectra, form colored salts and double salts, have a low electrode potential, are mainly amphoteric, yield weak bases and weak acids, and are oxidizing or reducing agents (From Grant & Hackh's Chemical Dictionary, 5th ed)

Top Publications

  1. Ibrahim H, Jamil T, Hegazy E. Application of zeolite prepared from Egyptian kaolin for the removal of heavy metals: II. Isotherm models. J Hazard Mater. 2010;182:842-7 pubmed publisher
    ..It was found that the uptake depend on hydrated ion diameter. This study may attract more interest due to the presence of large reservoirs of very cheap kaolin in Egypt from which both zeolite types were prepared...
  2. Drazkiewicz M, Skorzynska Polit E, Krupa Z. Effect of BSO-supplemented heavy metals on antioxidant enzymes in Arabidopsis thaliana. Ecotoxicol Environ Saf. 2010;73:1362-9 pubmed publisher
    ..However, differences between the effects of the individual metals on the enzymes were greater after 7 days of plant exposure...
  3. Zaini M, Amano Y, Machida M. Adsorption of heavy metals onto activated carbons derived from polyacrylonitrile fiber. J Hazard Mater. 2010;180:552-60 pubmed publisher
    ..activated carbons derived from polyacrylonitrile (PAN) fiber and to examine their feasibility of removing heavy metals from aqueous solution...
  4. Hon K, Wang S, Hung E, Lam H, Lui H, Chow C, et al. Serum levels of heavy metals in childhood eczema and skin diseases: friends or foes. Pediatr Allergy Immunol. 2010;21:831-6 pubmed publisher
    ..Environmental and hygiene factors have been incriminated. Although air and food pollution with heavy metals have been considered as possible culprits, these factors have never been investigated in Hong Kong...
  5. Rashed M. Monitoring of contaminated toxic and heavy metals, from mine tailings through age accumulation, in soil and some wild plants at Southeast Egypt. J Hazard Mater. 2010;178:739-46 pubmed publisher
    ..Raddiena and Aerva Javanica) were sampled and analysed for toxic metals (Hg, Cd, Pb and As) and associated heavy metals (Cr, Ag, Ni, Au, Mo, Zn, Mn and Cu) using ICP-MS, ICP-AES, CVAAS and FAAS techniques...
  6. Calabrò P. Impact of mechanical street cleaning and rainfall events on the quantity and heavy metals load of street sediments. Environ Technol. 2010;31:1255-62 pubmed publisher
    ..weather in order to quantify the impact of mechanical street cleaning and rainfall events on the quantity and heavy metals load of street sediments...
  7. Aboal J, Fernandez J, Boquete T, Carballeira A. Is it possible to estimate atmospheric deposition of heavy metals by analysis of terrestrial mosses?. Sci Total Environ. 2010;408:6291-7 pubmed publisher
    Here we present a critical review of diverse research studies involving estimation of atmospheric deposition of heavy metals from the concentrations of the contaminants in terrestrial moss...
  8. De T, De M, Das S, Ray R, Ghosh P. Level of heavy metals in some edible marine fishes of mangrove dominated tropical estuarine areas of Hooghly River, north east coast of Bay of Bengal, India. Bull Environ Contam Toxicol. 2010;85:385-90 pubmed publisher
    ..of some important marine fishes collected in and around Hooghly estuarine coastal areas were analyzed for the heavy metals Cu, Zn, Ni, Cd, Cr and Pb. The concentration range of Cu (16.22-47.97 ppm), Pb (12.40-19.96 ppm) and Zn (12...
  9. Gupta S, Pandotra P, Gupta A, Dhar J, Sharma G, Ram G, et al. Volatile (As and Hg) and non-volatile (Pb and Cd) toxic heavy metals analysis in rhizome of Zingiber officinale collected from different locations of North Western Himalayas by Atomic Absorption Spectroscopy. Food Chem Toxicol. 2010;48:2966-71 pubmed publisher
    Ginger is an important ingredient of spice and herbals. The monitoring of toxic heavy metals in the rhizome of ginger is important for protecting public health against the hazards of metal toxicity...

More Information

Publications62

  1. Huang G, Wang Y. Physiological and biochemical responses in the leaves of two mangrove plant seedlings (Kandelia candel and Bruguiera gymnorrhiza) exposed to multiple heavy metals. J Hazard Mater. 2010;182:848-54 pubmed publisher
    The accumulation of heavy metals and their effect on photosynthetic pigments, proline, glutathione (GSH) and phytochelatins (PCs-SH) were studied in the leaves of two mangrove plants seedlings (Kandelia candel and Bruguiera gymnorrhiza) ..
  2. Schembri M, Peplow G, Camilleri J. Analyses of heavy metals in mineral trioxide aggregate and Portland cement. J Endod. 2010;36:1210-5 pubmed publisher
    ..The raw materials and the manufacturing process can result in the inclusion of heavy metals in Portland cement...
  3. Machado M, Soares E, Soares H. Removal of heavy metals using a brewer's yeast strain of Saccharomyces cerevisiae: chemical speciation as a tool in the prediction and improving of treatment efficiency of real electroplating effluents. J Hazard Mater. 2010;180:347-53 pubmed publisher
    ..S.-Environmental Protection Agency and Portuguese law, respectively. This corresponded to a removal of nickel of 89%...
  4. Nkemka V, Murto M. Evaluation of biogas production from seaweed in batch tests and in UASB reactors combined with the removal of heavy metals. J Environ Manage. 2010;91:1573-9 pubmed publisher
    ..Reducing the concentration of heavy metals in the digestate will enable its use as a fertilizer...
  5. Zheng L, Wang W, Shi Y. The effects of alkaline dosage and Si/Al ratio on the immobilization of heavy metals in municipal solid waste incineration fly ash-based geopolymer. Chemosphere. 2010;79:665-71 pubmed publisher
    ..The methodologies described could provide a powerful set of tools for the systematic evaluation of element release from geopolymers...
  6. Li L, Xu Z, Wu J, Tian G. Bioaccumulation of heavy metals in the earthworm Eisenia fetida in relation to bioavailable metal concentrations in pig manure. Bioresour Technol. 2010;101:3430-6 pubmed publisher
    ..The bioaccumulation factors (BAFs) of E. fetida to heavy metals were Cd (2.749+/-0.441), Zn (0.594+/-0.200), Pb (0.274+/-0.101) and Cu (0.076+/-0.030)...
  7. Chen Y, Huang X, Han Z, Huang X, Hu B, Shi D, et al. Effects of bamboo charcoal and bamboo vinegar on nitrogen conservation and heavy metals immobility during pig manure composting. Chemosphere. 2010;78:1177-81 pubmed publisher
    ..4% BV was 23% lower than that in the treatment with 9% BC. The final results indicated that by adding BC or BC+BV into PM composting is an effective method to reduce TKN loss and control the mobility of Cu and Zn...
  8. Navarro Noya Y, Jan Roblero J, González Chávez M, Hernández Gama R, Hernandez Rodriguez C. Bacterial communities associated with the rhizosphere of pioneer plants (Bahia xylopoda and Viguiera linearis) growing on heavy metals-contaminated soils. Antonie Van Leeuwenhoek. 2010;97:335-49 pubmed publisher
    ..These plants grow on silver mine tailings with high concentration of heavy metals in Zacatecas, Mexico...
  9. Injang U, Noyrod P, Siangproh W, Dungchai W, Motomizu S, Chailapakul O. Determination of trace heavy metals in herbs by sequential injection analysis-anodic stripping voltammetry using screen-printed carbon nanotubes electrodes. Anal Chim Acta. 2010;668:54-60 pubmed publisher
    ..The present method offers high sensitivity and high throughput for on-line monitoring of trace heavy metals. The practical utility of our method was also demonstrated with the determination of Pb(II), Cd(II), and Zn(II) ..
  10. Hernandez A, Daponte A, Aguilera I, Fernández Ajuria A, Toro S, Martin Olmedo P, et al. Urinary levels of arsenic and heavy metals in children and adolescents living in the industrialised area of Ria of Huelva (SW Spain). Environ Int. 2010;36:563-9 pubmed publisher
    ..Between 2003 and 2004, we conducted a biomonitoring study of exposure to arsenic and some heavy metals (cadmium, chromium, copper and nickel) in urine samples of a representative sample (n=227) of children and ..
  11. Mireji P, Keating J, Hassanali A, Mbogo C, Muturi M, Githure J, et al. Biological cost of tolerance to heavy metals in the mosquito Anopheles gambiae. Med Vet Entomol. 2010;24:101-7 pubmed publisher
    ..Investigations were conducted to establish whether there are biological costs for tolerance to heavy metals in Anopheles gambiae Giles sensu stricto and to assess the potential impact of heavy metal pollution on ..
  12. Gnanamani A, Kavitha V, Radhakrishnan N, Suseela Rajakumar G, Sekaran G, Mandal A. Microbial products (biosurfactant and extracellular chromate reductase) of marine microorganism are the potential agents reduce the oxidative stress induced by toxic heavy metals. Colloids Surf B Biointerfaces. 2010;79:334-9 pubmed publisher
    ..Thus, the chosen isolate exhibit tolerance and growth with the increasing concentration of chromium...
  13. Kosnett M. Chelation for heavy metals (arsenic, lead, and mercury): protective or perilous?. Clin Pharmacol Ther. 2010;88:412-5 pubmed publisher
    Despite clinical experience that spans more than half a century, chelation for toxic heavy metals represents one of the most controversial and misapplied interventions in clinical toxicology...
  14. Gulati K, Banerjee B, Lall S, Ray A. Effects of diesel exhaust, heavy metals and pesticides on various organ systems: possible mechanisms and strategies for prevention and treatment. Indian J Exp Biol. 2010;48:710-21 pubmed
    ..Automobile exhaust (in air), heavy metals (in food and water) and pesticides (in air, food, soil and water) are the most common environmental pollutants ..
  15. Kang J, Lee S, Cho K, Ki S, Cha S, Kim J. Linking land-use type and stream water quality using spatial data of fecal indicator bacteria and heavy metals in the Yeongsan river basin. Water Res. 2010;44:4143-57 pubmed publisher
    ..The models proposed in this paper can be considered useful tools for developing land cover guidelines and for prioritizing locations for implementing management practices to maintain stream water quality standard in a large river basin...
  16. Wang Z, Chai L, Yang Z, Wang Y, Wang H. Identifying sources and assessing potential risk of heavy metals in soils from direct exposure to children in a mine-impacted city, Changsha, China. J Environ Qual. 2010;39:1616-23 pubmed
    ..and triangulated irregular network (TIN) model was successfully used to discriminate the sources of heavy metals. The direct exposure method, sequential indicator simulation, and geographical information system (GIS) ..
  17. Lämsä V, Levonen A, Leinonen H, Yla Herttuala S, Yamamoto M, Hakkola J. Cytochrome P450 2A5 constitutive expression and induction by heavy metals is dependent on redox-sensitive transcription factor Nrf2 in liver. Chem Res Toxicol. 2010;23:977-85 pubmed publisher
    ..Therefore, CYP2A5 upregulation could be a useful indicator for hepatic activation of the Nrf2 pathway...
  18. Sullivan J, Greenfield J, Cumberford G, Grant J, Stewart J. Extraction efficiencies of heavy metals in hydroethanolic solvent from herbs of commerce. J AOAC Int. 2010;93:496-8 pubmed
    ..b>Heavy metals may enter into the herbal manufacturing process via bioaccumulation from the harvest site or during postharvest ..
  19. Pikula J, Zukal J, Adam V, Bandouchova H, Beklova M, Hajkova P, et al. Heavy metals and metallothionein in vespertilionid bats foraging over aquatic habitats in the Czech Republic. Environ Toxicol Chem. 2010;29:501-6 pubmed publisher
    ..The present study confirms exposure of vespertilionid bats to toxic heavy metals (Pb, Cd) in the Czech Republic and provides data on the essential element Zn and the metal-binding protein MT ..
  20. Wang J, Zheng S, Shao Y, Liu J, Xu Z, Zhu D. Amino-functionalized Fe(3)O(4)@SiO(2) core-shell magnetic nanomaterial as a novel adsorbent for aqueous heavy metals removal. J Colloid Interface Sci. 2010;349:293-9 pubmed publisher
    ..Findings of the present work highlight the potential for using amino-functionalized Fe(3)O(4)@SiO(2) magnetic nanoparticles as an effective and recyclable adsorbent for the removal of heavy metal ions in water and wastewater treatment...
  21. Li C, Xie F, Ma Y, Cai T, Li H, Huang Z, et al. Multiple heavy metals extraction and recovery from hazardous electroplating sludge waste via ultrasonically enhanced two-stage acid leaching. J Hazard Mater. 2010;178:823-33 pubmed publisher
    An ultrasonically enhanced two-stage acid leaching process on extracting and recovering multiple heavy metals from actual electroplating sludge was studied in lab tests...
  22. Gu Q, Lin R. Heavy metals zinc, cadmium, and copper stimulate pulmonary sensory neurons via direct activation of TRPA1. J Appl Physiol (1985). 2010;108:891-7 pubmed publisher
    ..In addition, our study showed that two other heavy metals, cadmium and copper, also stimulated pulmonary sensory neurons via a direct activation of TRPA1...
  23. Nakipoglu Y, Gümüş D, Sertel Selale D, Küçüker M. [In vitro susceptibility of Enterococcus strains to high level aminoglycosides and heavy metals]. Mikrobiyol Bul. 2009;43:545-51 pubmed
    The widespread use of antimicrobial agents in the hospitals and environmental contamination with heavy metals are increasingly related to resistance progression in microorganisms...
  24. Jia L, Wang W, Li Y, Yang L. Heavy metals in soil and crops of an intensively farmed area: a case study in Yucheng City, Shandong Province, China. Int J Environ Res Public Health. 2010;7:395-412 pubmed publisher
    ..But the long-term accumulation of heavy metals in soil has lead to an increase of Ni, As, Hg and Pb concentrations in some of wheat and corn samples and Cd in ..
  25. Li S, Zhang Q. Risk assessment and seasonal variations of dissolved trace elements and heavy metals in the Upper Han River, China. J Hazard Mater. 2010;181:1051-8 pubmed publisher
    ..The results demonstrated that concentrations of 11 heavy metals showed significant seasonality and most variables exhibited higher levels in the rainy season...
  26. Tabari S, Saravi S, Bandany G, Dehghan A, Shokrzadeh M. Heavy metals (Zn, Pb, Cd and Cr) in fish, water and sediments sampled form Southern Caspian Sea, Iran. Toxicol Ind Health. 2010;26:649-56 pubmed publisher
    Environmental pollution is a worldwide problem, heavy metals belonging to the most important pollutants. The progress of industries has led to increased emission of pollutants into ecosystems...
  27. Kerin E, Lin H. Fugitive dust and human exposure to heavy metals around the Red Dog Mine. Rev Environ Contam Toxicol. 2010;206:49-63 pubmed publisher
    Fugitive dust from the Red Dog Mine is a potential source of exposure to heavy metals for residents of the surrounding area...
  28. Li Y, Liu J, Cao Z, Lin C, Yang Z. Spatial distribution and health risk of heavy metals and polycyclic aromatic hydrocarbons (PAHs) in the water of the Luanhe River Basin, China. Environ Monit Assess. 2010;163:1-13 pubmed publisher
    The objectives of this study were to investigate the contamination levels and dispersion patterns of heavy metals and polycyclic aromatic hydrocarbons (PAHs) and to estimate the risk to health effects within the Luanhe river basin of ..
  29. Nawaz S, Nagra S, Saleem Y, Priyadarshi A, Priydarshi A. Determination of heavy metals in fresh water fish species of the River Ravi, Pakistan compared to farmed fish varieties. Environ Monit Assess. 2010;167:461-71 pubmed publisher
    ..The concentrations of heavy metals, such as As, Cd, Cu, Pb, Hg, and Zn, and electrolytes Ca, K, and Na were determined in different edible and non-..
  30. Mansour S, Belal M, Abou Arab A, Gad M. Monitoring of pesticides and heavy metals in cucumber fruits produced from different farming systems. Chemosphere. 2009;75:601-9 pubmed publisher
    ..Contamination among the three types of cucumber either by pesticides or heavy metals varied from a season to another...
  31. Ogwok P, Muyonga J, Sserunjogi M. Pesticide residues and heavy metals in Lake Victoria Nile perch, Lates niloticus, belly flap oil. Bull Environ Contam Toxicol. 2009;82:529-33 pubmed publisher
    ..The oil was analyzed for pesticide residues and heavy metals. Total residual concentration of dichlorodiphenyltrichloroethane, endosulfan, hexachlorocyclohexane, ..
  32. Xiaoni H, Hong L, Danfeng S, Liandi Z, Baoguo L. Multi-scale spatial structure of heavy metals in agricultural soils in Beijing. Environ Monit Assess. 2010;164:605-16 pubmed publisher
    To effectively investigate the spatial variability of heavy metals in soil, produce a higher quality spatial distribution map, and identify the potential pollution sources of heavy metals, geostatistics was employed to evaluate the effect ..
  33. Whyte A, Hook G, Greening G, Gibbs Smith E, Gardner J. Human dietary exposure to heavy metals via the consumption of greenshell mussels (Perna canaliculus Gmelin 1791) from the Bay of Islands, northern New Zealand. Sci Total Environ. 2009;407:4348-55 pubmed publisher
    ..Based on the average values detected in the current study, the concentrations of heavy metals ingested in a 'typical diet' containing greenshell mussels are below the provisional tolerable weekly intake (..
  34. Chang F, Chen J, Wey M, Tsai S. Effects of particulates, heavy metals and acid gas on the removals of NO and PAHs by V2O5-WO3 catalysts in waste incineration system. J Hazard Mater. 2009;170:239-46 pubmed publisher
    ..for simultaneous removals of NO and polycyclic aromatic hydrocarbons (PAHs) and the influences of particulates, heavy metals, SO(2), and HCl on the performances of catalysts...
  35. Ventrella A, Catucci L, Piletska E, Piletsky S, Agostiano A. Interactions between heavy metals and photosynthetic materials studied by optical techniques. Bioelectrochemistry. 2009;77:19-25 pubmed publisher
    In this work studies on rapid inhibitory interactions between heavy metals and photosynthetic materials at different organization levels were carried out by optical assay techniques, investigating the possibility of applications in the ..
  36. Prasher D. Heavy metals and noise exposure: health effects. Noise Health. 2009;11:141-4 pubmed publisher
    b>Heavy metals are chemical elements with a specific gravity that is atleast five times that of water which is 1 at 4 degrees C. The commonly encountered heavy metals are lead,mercury, cadmium, and arsenic...
  37. Khan S, Ahmad I, Shah M, Rehman S, Khaliq A. Use of constructed wetland for the removal of heavy metals from industrial wastewater. J Environ Manage. 2009;90:3451-7 pubmed publisher
    ..study was conducted to investigate the effectiveness of a continuous free surface flow wetland for removal of heavy metals from industrial wastewater, in Gadoon Amazai Industrial Estate (GAIE), Swabi, Pakistan...
  38. Meers E, Van Slycken S, Adriaensen K, Ruttens A, Vangronsveld J, Du Laing G, et al. The use of bio-energy crops (Zea mays) for 'phytoattenuation' of heavy metals on moderately contaminated soils: a field experiment. Chemosphere. 2010;78:35-41 pubmed publisher
    ..Metal removal is very low for Cd and Pb but more significant for Zn with an annual reduction of 0.4-0.7 mgkg(-1) in the top soil layer...
  39. Yang B, Zhou M, Shu W, Lan C, Ye Z, Qiu R, et al. Constitutional tolerance to heavy metals of a fiber crop, ramie (Boehmeria nivea), and its potential usage. Environ Pollut. 2010;158:551-8 pubmed publisher
  40. Ruta L, Paraschivescu C, Matache M, Avramescu S, Farcasanu I. Removing heavy metals from synthetic effluents using "kamikaze" Saccharomyces cerevisiae cells. Appl Microbiol Biotechnol. 2010;85:763-71 pubmed publisher
    ..designed to clean up heavy metal contaminated environments is growing resistant cells that accumulate the heavy metals to ensure better removal through a combination of biosorption and continuous metabolic uptake after physical ..
  41. Businelli D, Massaccesi L, Said Pullicino D, Gigliotti G. Long-term distribution, mobility and plant availability of compost-derived heavy metals in a landfill covering soil. Sci Total Environ. 2009;407:1426-35 pubmed publisher
    ..The long-term distribution, mobility and phytoavailability of heavy metals in such anthropogenic soils were studied by collecting soil samples at different depths over a 10 y ..
  42. Radwan M, el Gendy K, Gad A. Oxidative stress biomarkers in the digestive gland of Theba pisana exposed to heavy metals. Arch Environ Contam Toxicol. 2010;58:828-35 pubmed publisher
  43. Zhuang P, McBride M, Xia H, Li N, Li Z. Health risk from heavy metals via consumption of food crops in the vicinity of Dabaoshan mine, South China. Sci Total Environ. 2009;407:1551-61 pubmed publisher
    ..Bio-accumulation factors for heavy metals in different vegetables showed a trend in the order: Cd>Zn>Cu>Pb...
  44. Wang J, Chen C. Biosorbents for heavy metals removal and their future. Biotechnol Adv. 2009;27:195-226 pubmed publisher
    ..Biosorbents are cheaper, more effective alternatives for the removal of metallic elements, especially heavy metals from aqueous solution...
  45. Danh L, Truong P, Mammucari R, Tran T, Foster N. Vetiver grass, Vetiveria zizanioides: a choice plant for phytoremediation of heavy metals and organic wastes. Int J Phytoremediation. 2009;11:664-91 pubmed publisher
    ..5 dS m(-1)), sodicity (ESP 48%), anda wide range of heavy metals (As, Cd, Cr, Cu, Hg, Ni, Pb, Se, and Zn). Vetiver can accumulate heavy metals, particularly lead (shoot 0...
  46. Wang W, Shao Z, Liu Y, Wang G. Removal of multi-heavy metals using biogenic manganese oxides generated by a deep-sea sedimentary bacterium - Brachybacterium sp. strain Mn32. Microbiology. 2009;155:1989-96 pubmed publisher
    ..This study provides potential applications of a new marine Mn(II)-oxidizing bacterium in heavy metal bioremediation and increases our basic knowledge of microbial manganese oxidation mechanisms...
  47. Mari M, Nadal M, Schuhmacher M, Domingo J. Exposure to heavy metals and PCDD/Fs by the population living in the vicinity of a hazardous waste landfill in Catalonia, Spain: health risk assessment. Environ Int. 2009;35:1034-9 pubmed publisher
    ..performed a probabilistic study focused on assessing human health risks derived from environmental exposure to heavy metals and polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) around the HWL...
  48. Anwar Mohamed A, Elbekai R, El Kadi A. Regulation of CYP1A1 by heavy metals and consequences for drug metabolism. Expert Opin Drug Metab Toxicol. 2009;5:501-21 pubmed
    ..With the growing human exposure to heavy metals, emerging evidence suggests that heavy metals exposure alter CYP1A1 enzyme activity...
  49. Quandt S, Jones B, Talton J, Whalley L, Galvan L, Vallejos Q, et al. Heavy metals exposures among Mexican farmworkers in eastern North Carolina. Environ Res. 2010;110:83-8 pubmed publisher
    ..Because farmworkers are exposed to neurotoxic pesticides, they may be at risk for adverse health effects from the combined exposure...
  50. Kavamura V, Esposito E. Biotechnological strategies applied to the decontamination of soils polluted with heavy metals. Biotechnol Adv. 2010;28:61-9 pubmed publisher
    Soils have been submitted to several contaminants that vary in concentration and composition. Heavy metals can be widely spread and accumulated in those environments due to some inappropriate actions...
  51. Diels L, Van Roy S, Taghavi S, Van Houdt R. From industrial sites to environmental applications with Cupriavidus metallidurans. Antonie Van Leeuwenhoek. 2009;96:247-58 pubmed publisher
    ..These polysaccharides contribute also to flotation under specific conditions in a soil-heavy metals-bacteria suspension mixture...
  52. Joshi P, Juwarkar A. In vivo studies to elucidate the role of extracellular polymeric substances from Azotobacter in immobilization of heavy metals. Environ Sci Technol. 2009;43:5884-9 pubmed
    ..uptake of cadmium (Cd) and chromium (Cr) by wheat plants cultivated in soils contaminated with the respective heavy metals has been demonstrated. A heavy metal-resistant strain of Azotobacter spp. was isolated and identified...
  53. Thomas L, Hodgson S, Nieuwenhuijsen M, Jarup L. Early kidney damage in a population exposed to cadmium and other heavy metals. Environ Health Perspect. 2009;117:181-4 pubmed publisher
    Exposure to heavy metals may cause kidney damage. The population living near the Avonmouth zinc smelter has been exposed to cadmium and other heavy metals for many decades.