Cold Vapor Atomic Absorption Spectrometry Research Articles

The mercury levels in crustaceans and cephalopods from Peninsular Malaysia.

This study is to determine total mercury in edible tissues of eight species of cephalopods and 12 species of crustaceans purchased from 11 identified major fish landing ports and wet markets throughout Peninsular Malaysia. The concentration of mercury was measured by cold vapor atomic absorption spectrometry (AAS) technique using the Perkin Elmer Flow Injection Mercury System (FIMS-400). In general, the mercury levels were low with concentrations in cephalopods ranging from 0.099 to 2.715mg/kg dry weight (or 0.0184-0.505mg/kg wet weight) and in crustaceans ranging from 0.057 to 1.359mg/kg dry weight (or 0.0111-0.265mg/kg wet weight). The mercury levels showed no significant differences (P > 0.05) between species for both cephalopods and crustaceans. There was no significant correlation between mercury concentrations and the body size of individual for both groups as well. Comparisons with mercury levels obtained found from other previous studies and/or species noted that they were of the same magnitude or relatively low compared to various locations reported worldwide.

Content of selected elements in Boletus badius fruiting bodies growing in extremely polluted wastes

The aim of the study was to analyse levels of 17 trace elements and 5 major minerals in 11 Boletus badius fruiting bodies able to grow in extremely polluted waste (flotation tailings) and polluted soil in southern Poland. The presented data widen the limited literature data about the abilities of wild-growing mushroom species to grow on heavily contaminated substrates. Content of elements in waste, soil and mushrooms was analysed by flame atomic absorption spectrometry (FAAS) and cold vapour atomic absorption spectrometry (CVAAS - Hg). The industrial areas differed greatly as regards the content of elements in flotation tailings and soil; therefore differences in Ag, Ba, Cd, Co, Fe, Mo, Ni, Pb, Ca, K, Mg, Na and P accumulation in mushrooms were observed. The highest contents of elements in mushrooms were observed for: As, Al, Cu and Zn (86 ± 28, 549 ± 116, 341 ± 59 and 506 ± 40 mg kg−1 dry matter, respectively). Calculated bioconcentration factor (BCF) values were higher than 1 for Al (15.1–16.9), Fe (10.6–24.4) and Hg (10.2–16.4) only. The main value of the presented results is the fact that one of the common wild-growing mushroom species was able to grow on flotation tailings containing over 22 g kg−1 of As and, additionally, effective accumulation of other elements was observed. In view of the high content of the majority of analysed elements in fruiting bodies, edible mushrooms from such polluted areas are nonconsumable.

Determination of mercury(II) ions in seafood samples after extraction and preconcentration by a novel functionalized magnetic metal-organic framework nanocomposite.

This work describes a novel functionalized magnetic metal-organic framework nanocomposite [(Fe3O4-2,5-dimercapto-1,3,4-thiadiazole)/metal-organic framework] and its application in the preconcentration of Hg(II) ions. The parameters affecting the preconcentration procedure were optimized by a Box-Behnken design through response surface methodology. Three variables (uptake time, magnetic nanosorbent amount, and pH value) were selected as the main factors affecting the sorption step, while four variables (type, volume, and concentration of the eluent; and elution time) were selected as main factors in the optimization study of the elution step. Following the sorption and elution of analytes, the ions were quantified by cold vapor atomic absorption spectrometry. Under the optimum conditions, the limit of detection was 0.01 ng/mL and all the relative standard deviations were less than 10%. The obtained sorption capacity (in mg/g) of this new sorbent was 124. Ultimately, this nanocomposite was successfully applied to the rapid extraction of trace quantities of Hg(II) ions in seafood samples and satisfactory results were obtained.

Assessment of selenium and mercury in biological samples of normal and night blindness children of age groups (3-7) and (8-12) years.

The causes of night blindness in children are multifactorial and particular consideration has been given to childhood nutritional deficiency, which is the most common problem found in underdeveloped countries. Such deficiency can result in physiological and pathological processes that in turn influence biological sample composition. This study was designed to compare the levels of selenium (Se) and mercury (Hg) in scalp hair, blood, and urine of night blindness children age ranged (3-7) and (8-12) years of both genders, comparing them to sex- and age-matched controls. A microwave-assisted wet acid digestion procedure was developed as a sample pretreatment for the determination of Se and Hg in biological samples of night blindness children. The proposed method was validated by using conventional wet digestion and certified reference samples of hair, blood, and urine. The Se and Hg in biological samples were measured by electrothermal atomic absorption spectrometry and cold vapor atomic absorption spectrometry, prior to microwave acid digestion, respectively. The concentration of Se was decreased in scalp hair and blood samples of male and female night blindness children while Hg was higher in all biological samples as compared to referent subjects. The Se concentration was inversely associated with the risk of night blindness in both genders. These results add to an increasing body of evidence that Se is a protecting element for night blindness. These data present guidance to clinicians and other professional investigating deficiency of essential micronutrients in biological samples (scalp hair and blood) of night blindness children.

Estimation of seasonal risk caused by the intake of lead, mercury and cadmium through freshwater fish consumption from urban water reservoirs in arid areas of northern Mexico.

Bioavailability and hence bioaccumulation of heavy metals in fish species depends on seasonal conditions causing different risks levels to human health during the lifetime. Mercury, cadmium and lead contents in fish from Chihuahua (Mexico) water reservoirs have been investigated to assess contamination levels and safety for consumers. Muscle samples of fish were collected across the seasons. Lead and cadmium were analyzed by inductively coupled plasma-optical emission spectrometry, and mercury by cold-vapor atomic absorption spectrometry. The highest concentrations of cadmium (0.235 mg/kg), mercury (0.744 mg/kg) and lead (4.298 mg/kg) exceeded the maximum levels set by European regulations and Codex Alimentarius. Lead concentrations found in fish from three water reservoirs also surpassed the limit of 1 mg/kg established by Mexican regulations. The provisional tolerable weekly intake (PTWI) suggested by the World Health Organization for methyl mercury (1.6 µg/kg bw per week) was exceeded in the spring season (1.94 µg/kg bw per week). This might put consumers at risk of mercury poisoning.

Coupling of non-selective adsorption with selective elution for novel in-line separation and detection of cadmium by vapour generation atomic absorption spectrometry

Non-selective adsorption of Cd2+ ions on a cation exchange fiber and subsequent selective elution with a KI solution has been strategically utilized to develop a highly selective in-line separation of Cd2+ ions from other metal ions for its rapid and reliable quantification by cold vapour-atomic absorption spectrometry. After retention of Cd2+ with a high efficiency on cation exchange fiber, selective elution of the retained Cd2+ was subsequently accomplished with 0.3M KI. Vapour generation of Cd for in-line CV-AAS determination was then achieved by merging the eluate with HCl and NaBH4. Interferences from most base metals with the vapour generation of Cd were eliminated by this approach, with the exception of Pb2+ions which was removed by co-precipitation with BaSO4 prior to the in-line separation. Substantial improvement in sensitivity of the in-line CV-AAS determination of Cd was achieved by increasing the sample loading time. A detection limit of 0.6ngL−1 (3σ) was obtained with sample loading time of 120s, corresponding to a consumption of 24mL of sample solution. Application of the method to the determination of Cd in certified sediment and fish samples gave a good agreement with the certified values. Further validation by recovery study in real fish sample digests and water gave average Cd recoveries of 98.7±1.0% for fish and 92±3% for water with RSD of 1.5% for fish and 4% for water, respectively.

Feasibility of Using AAS for the Characterization of a Tuna Fish Candidate Reference Material for Total Hg and Methyl-Hg Measurement

This work describes the evaluation of several parameters for preparing a tuna fish candidate reference material (RM) in order to measure its total Hg and methyl-Hg mass fractions by cold vapor atomic absorption spectrometry (CV-AAS) and solid sampling graphite furnace atomic absorption spectrometry (SS-GF AAS). Best results were acquired after extraction with toluene and L-cysteine for 15 min at 80 °C. The parameters investigated were stability of chemical composition during production, homogeneity and analyte segregation. No analyte segregation was observed and the material was shown to be stable even when stored at 50 °C for 10 months. Total Hg mass fraction was 3.03 ± 0.22 µg g-1 by CV AAS, 2.99 ± 0.43 µg g-1 by SS-GF AAS and 2.95 ± 0.15 µg g-1 by direct mercury analyser (DMA). Methyl-Hg mass fraction was 2.49 ± 0.13 µg g-1 by CV AAS and 2.44 ± 0.46 µg g-1 by SS-GF AAS.

Robust ultrasound assisted extraction approach using dilute TMAH solutions for the speciation of mercury in fish and plant materials by cold vapour atomic absorption spectrometry (CVAAS)

A simple and robust ultrasound assisted extraction (UAE) protocol with dilute solutions of tetramethyl ammonium hydroxide (TMAH) for the speciation of mercury in fish and plant tissues was developed by CVAAS as an alternative to conventional methods.

Development of a deep-sea mercury sensor using <i>in situ</i> anodic stripping voltammetry

Copyright © 2015 by The Geochemical Society of Japan. mercury in seawater can be an indicator of widespread underwater mineral deposits (Marumo et al., 2008; Tomiyasu et al., 2007). Therefore, deep-sea mercury monitoring is very important to both the caution of environmental pollution and the exploration of underwater mineral deposits. Due to their high sensitivity, cold vapor atomic absorption spectrometry (CV-AAS) (Chakraborty et al., 2014a, c), cold vapor atomic fluorescence spectrometry (CV-AFS) (Fernandez-Martinez et al., 2015), and inductively coupled plasma mass spectrometry (ICP-MS) (Baya et al., 2015) have been the most commonly used for the measurement of total mercury. All of these techniques require expensive and sophisticated instrumentation combined with complicated sample preparation processes (Chakraborty et al., 2015; Ferreira et al., 2015; Giacomino et al., 2008). Sample collection needs certain spatial and temporal resolutions of the target fields, and there is a risk of contamination and/or loss of mercury during the sampling and transfer of water from depth to the surface Development of a deep-sea mercury sensor using in situ anodic stripping voltammetry

Total Mercury Determination in Petroleum Green Coke and Oily Sludge Samples by Cold Vapor Atomic Fluorescence Spectrometry

A fast, simple and reliable method for Hg determination in green coke and oily sludge samples by atomic fluorescence spectrometry is described. Microwave digestion and extraction procedures were evaluated for highly complex samples of coke and oily sludge. The concentrations of SnCl2 and HCl to promote Hg vapor, were optimized, as well as the concentration of KMnO4, to stabilize the Hg2+ before the atomic vapor formation. Accuracy of the method was evaluated through certified reference material, for green coke, and comparison with cold vapor atomic absorption spectrometry (CV AAS), for oily sludge. Recovery tests were also performed. Limits of detection and quantification were 0.8 and 2.6 µg kg−1, respectively. Ten green coke and nine sludge samples were analysed and Hg concentrations in coke are very low, between 0.005 and 0.065 mg kg−1, but oily sludge samples have high concentrations, ranging from 42.5 to 376.6 mg kg−1, requiring careful management.

Heavy metals content of canned tuna fish: estimated weekly intake

Present study was aimed at investigating the tree heavy metals namely Cadmium, lead and mercury measured in canned tuna fish which was collected from large Moroccan supermarkets and grocery stores. Heavy metals amounts were determined in samples using graphite furnace and cold vapor atomic absorption spectrometry. The levels of Hg samples were generally higher than those of Pb and Cd. This study has revealed that the concentrations of trace elements in canned tuna fish were below the maximum acceptable concentrations for human consumption. Metal concentrations in the Moroccan canned tuna fish were assessed for human uses according to provisional tolerable weekly and daily intake. The estimated values of all metals in samples in this study were below the established values. Therefore, it can be concluded that those metals in tuna, posed no health problems for consumers.

Mercury and selenium relationship in a tropical estuarine fish

Event Abstract Back to Event Mercury and selenium relationship in a tropical estuarine fish André Pinheiro Almeida1, Ana Carolina Pizzochero1 and Paulo Renato Dorneles1* 1 Federal University of Rio de Janeiro, Carlos Chagas Filho Biophysics Institute, Brazil Aquatic systems have been considered as final sinks for persistent and bioaccumulative toxicants (PBTs), such as metals and organohalogen compounds. Among the trace elements, non-essential metals deserve special attention due to their toxicity. In this context, mercury (Hg) should be highlighted due to its toxic effects, which comprise neurotoxicity, nephrotoxicity, hepatotoxicity, genotoxicity, among others. Several studies have highlighted the selenium-mediated methylmercury detoxification process, via mercury selenide formation in tissues of marine vertebrates. Despite being an essential element, selenium may also be toxic in high concentrations. This study focused on Guanabara Bay (GB), a heavily polluted urban estuary in Rio de Janeiro state (Brazil), where the whitemouth croaker (Micropogonias furnieri) provides a valuable fishery resource. Therefore, hepatic (Hg and Se) and muscular (Hg) concentrations of these elements were determined in GB whitemouth croakers. Mercury and selenium measurements were performed by cold vapor atomic absorption spectrometry (CV-AAS) and electrothermal AAS (ET-AAS), respectively. Total mercury (THg) concentrations in muscle (n=19) ranged from 184.9 to 858.6 (ng/g), while in liver they varied from 11.05 to 1188 (ng/g). Hepatic selenium concentrations ranged from 7820 to 40085 (ng/g). The hepatic Se:THg molar ratio ranged from 40,8 to 3102,5. The results showed a significant correlation between hepatic mercury and selenium levels, but the molar ratio suggests the absence of mercury selenide formation. Some of the Se concentrations found were above the threshold level for freshwater fish (12000 ng/g); however, it is not yet clear if these concentrations are toxic for marine fish as well. More studies are necessary for evaluating the impact of such exposure in fish from Guanabara Bay. Acknowledgements This study was supported by CNPq (National Research Council, Brazilian Ministry of Science and Technology) and FAPERJ (Rio de Janeiro state Research Support Foundation). Keywords: Whitemouth croaker, Micropogonias furnieri, Guanabara Bay, Tropical estuary, mercury selenide. Conference: XV European Congress of Ichthyology, Porto, Portugal, 7 Sep - 11 Sep, 2015. Presentation Type: Poster Presentation Topic: Physiology, Behavior and Toxicology Citation: Almeida A, Pizzochero A and Dorneles P (2015). Mercury and selenium relationship in a tropical estuarine fish. Front. Mar. Sci. Conference Abstract: XV European Congress of Ichthyology. doi: 10.3389/conf.FMARS.2015.03.00146 Copyright: The abstracts in this collection have not been subject to any Frontiers peer review or checks, and are not endorsed by Frontiers. They are made available through the Frontiers publishing platform as a service to conference organizers and presenters. The copyright in the individual abstracts is owned by the author of each abstract or his/her employer unless otherwise stated. Each abstract, as well as the collection of abstracts, are published under a Creative Commons CC-BY 4.0 (attribution) licence (https://creativecommons.org/licenses/by/4.0/) and may thus be reproduced, translated, adapted and be the subject of derivative works provided the authors and Frontiers are attributed. For Frontiers’ terms and conditions please see https://www.frontiersin.org/legal/terms-and-conditions. Received: 24 Nov 2015; Published Online: 27 Nov 2015. * Correspondence: PhD. Paulo Renato Dorneles, Federal University of Rio de Janeiro, Carlos Chagas Filho Biophysics Institute, Rio de Janeiro, Rio de Janeiro, 21941-902, Brazil, dornelespr@biof.ufrj.br Login Required This action requires you to be registered with Frontiers and logged in. To register or login click here. Abstract Info Abstract The Authors in Frontiers André Pinheiro Almeida Ana Carolina Pizzochero Paulo Renato Dorneles Google André Pinheiro Almeida Ana Carolina Pizzochero Paulo Renato Dorneles Google Scholar André Pinheiro Almeida Ana Carolina Pizzochero Paulo Renato Dorneles PubMed André Pinheiro Almeida Ana Carolina Pizzochero Paulo Renato Dorneles Related Article in Frontiers Google Scholar PubMed Abstract Close Back to top Javascript is disabled. Please enable Javascript in your browser settings in order to see all the content on this page.

Lead, mercury and arsenic content in spices: Black, white and green pepper, black cumin and ginger

In order to evaluate the safety of selected commercial spices brands, concentration of lead, mercury and arsenic, as well as moisture and mineral contents were analyzed in samples of dried black and white pepper powders, black, white and green peppercorns, black cumin seeds and ginger powder. Lead (Pb), mercury (Hg) and arsenic (As) concentrations in spice samples purchased from local markets in Belgrade were determined, after a microwave digestion of the samples, by atomic absorption spectrometry (AAS), using the graphite furnace AAS technique (Pb), cold vapor AAS technique (Hg) and hydride generation AAS technique (As). Trace levels of Pb, Hg and As in the selected dried spices samples were in the range 0.10 ppm - 0.79 ppm, 0.01 ppm - 0.10 ppm and 0.01 ppm - 0.51 ppm, respectively. The maximum Pb concentration was determined in the sample of ginger and it was 0.79 ppm, the maximum concentration of Hg was 0.10 ppm, determined in green peppercorns samples, while the maximum concentration of As in powdered black pepper sample was 0.51 ppm. The moisture and mineral contents in the different analyzed spices were in the range 1.70-13.10% and 3.40-6.50%, respectively. According to the obtained results, the concentrations of the analyzed toxic elements, as well as the moisture and mineral content in selected spices, were below the maximum permissible limits declared by the national legislations deemed safe for human consumption.

A Simplified Digestion Protocol for the Analysis of Hg in Fish by Cold Vapor Atomic Absorption Spectroscopy

Analysis of mercury in fish is an interesting problem with the potential to motivate students in chemistry laboratory courses. The recommended method for mercury analysis in fish is cold vapor atomic absorption spectroscopy (CVAAS), which requires homogeneous analyte solutions, typically prepared by acid digestion. Previously published digestion protocols require multiple acids, long heating periods or harsh conditions, and reducing agents for workup. We developed a simplified protocol for the digestion of fish that requires only nitric acid and a short heating period. This protocol was successfully implemented in an instrumental analysis lab and enabled students to perform CVAAS on commercial fish samples within the time constraints of an undergraduate lab course.

Determination of Mercury in Iron Supplement Using Slurry Sampling and Cold Vapor Atomic Absorption Spectrometry

This paper proposes a method using slurry sampling and cold vapor atomic absorption spectrometry (CV AAS) for the determination of mercury in iron supplement used for the treatment of anemia. The optimization step of the slurry preparation was performed using a two-level full factorial design involving the experimental factors: hydrochloric acid concentration, thiourea concentration and sonication time, having as chemometric response the absorbance. Employing the optimized conditions, the method allows the determination of mercury, using external calibration technique, with limits of detection and quantification of 30 and 102 ng L-1, respectively. The precision expressed as a relative standard deviation (RSD) was 10.89 and 6.84% for supplement samples with mercury content of 4.82 and 9.61 ng g-1, respectively. The limits of detection and quantification, considering a sample mass of 1.2 g, were 0.63 a 2.10 ng g-1, respectively. There is no certified reference material of ferrous supplement for evaluation of the accuracy. Thus, addition/recovery tests were performed to evaluate the accuracy of the method. The recovery values achieved varied from 85 to 106%, confirming the applicability of this method for mercury quantification in these iron matrices. The method was satisfactorily applied for the determination of mercury in twelve iron supplement samples with different chemical compositions. In six samples, the mercury content was lower than the limit of quantification (2.10 ng g-1) and in the other six samples, the mercury content varied from 3.17 to 34.86 ng g-1. Keywords: Anemia, CV AAS, iron supplement, mercury, slurry sampling, thiourea.

Highly selective solid phase extraction of mercury ion based on novel ion imprinted polymer and its application to water and fish samples

A novel ion imprinted polymer (IIP) material has been synthesized for mercury ion. The IIP material is applied to the solid phase extraction (SPE) of Hg2+ from complex matrixes including water and fish samples. The IIP-SPE method is operated prior to cold vapor atomic absorption spectroscopy (CV-AAS) to determine mercury ion. In the polymer synthesis, mercury ion, 2-vinylpyridine, ethyleneglycol dimethacrylate and 2,2′-azobisisobutyronitrile are used as target, Hg2+ complexing reagent monomer, cross-linker and initiator, respectively. The polymer is characterized on the basis of FT-IR and thermal analysis (thermogravimetric, TGA; differential thermic, DTA; and differential scanning calorimetry, DSC). The obtained polymer block is ground, sieved and Hg2+ ions are removed from polymer particles by leaching with EDTA, which leaves a cavity in the polymer particles. The maximum Hg2+ adsorption capacity of IIP is 24.6 mg/g. Effective parameters on retaining Hg2+ such as pH, flow rate of sample and eluent, nature of the eluent, ionic strength, selectivity coefficient and retention capacity are investigated. The detection limit and the relative standard deviation are 5 × 10−4 ng/mL and 2.4%, respectively. After 20 adsorption cycles, the recovery of Hg2+ on IIP is only decreased by 3.2%. The column selective adsorption experiments of Na+, Cu2+, Pb2+, Cd2+, Ca2+ and Mg2+ ions with respect to mercury are conducted by using imprinted and non-imprinted polymer. These results showed that the IIP is highly selective for Hg2+ over the other metals.

Investigation on mineral composition and accumulation by popular edible mushroom common chanterelle (Cantharellus cibarius)

In this study accumulation, content and multivariate relationship of Ag, Al, Ba, Ca, Cd, Co, Cr, Cu, Fe, Hg, K, Mg, Mn, Na, Ni, Pb, P, Rb, Sr and Zn in Cantharellus cibarius and topsoil collected from four places of Central and Northeastern Poland were investigated. Mercury was determined using cold vapor atomic absorption spectroscopy and other elements by inductively coupled plasma-optical emission spectroscopy. Principal Component Analysis (PCA) was used to examine the interdependences between 20 elements sequestered in fruit bodies by C. cibarius and in the soil substratum. Fruit bodies of Common Chanterelle from all places investigated can be considered as relatively abundant in essential elements such as: K, P, Mg, Na, Ca, Fe, Zn, Cu, Mn and Co. This mushroom effectively accumulates Rb, K, P, Cu, Cd, Ag, Na and Zn from the soil substratum, while Al, Ba, Cr, Fe and Pb are excluded.

Temperature stability of mercury compounds in solid substrates

Abstract The major aim of the newly adopted Mercury Convention is to reduce global mercury (Hg) emissions to the environment. In high temperature industrial processes, including coal combustion, Hg compounds present as impurities in solid materials are decomposed and evaporated leading to the emission of Hg to the atmosphere. The behaviour of different Hg compounds and their mixtures during heating have been the subject of numerous studies, and is the topic of the present work. Controlled heating can be used to fractionate Hg compounds in solid substrates, offering the possibility of identification and quantification of Hg compounds. In the attempt to develop a method for temperature fractionation of Hg, experiments were conducted with pure Hg compounds, and the compounds mixed with different substrates (SiO2 and CaSO4 • 2H2O), for calibration purposes. Detection was performed by two methods, namely Cold Vapour Atomic Absorption Spectrometry (CV AAS) with Zeeman background correction, and Nier-type Mass Spectrometry with a Knudsen cell (MS). Further investigation is in process.

Bone char surface modification by nano-gold coating for elemental mercury vapor removal

The present work was done to develop a novel nanocomposite using bone char coated with nano-gold for capture of elemental mercury (Hg0) from air. The morphologies, structures, and chemical constitute of the prepared nanocomposite were evaluated by UV–VIS–NIR, dynamic light-scattering (DLS), X-ray diffraction (XRD), transmission electron microscopy (TEM), Fourier transform infra-red (FTIR) spectroscopy, and energy dispersive X-ray spectroscopy (EDS). The capture performance of nanocomposite was evaluated in a needle trap for mercury vapor. An on-line setup based on cold vapor atomic absorption spectrometry (CVAAS) was designed for Hg0 determination. Dynamic capacity of nanocomposite for Hg0 was shown high efficient operating capacity of 586.7μg/g. As temperature increases, the dynamic adsorption capacity of the nanocomposite was decreased, which are characteristics of physicosorption processes. It was found that the surface modification of bone char with nano-gold has various advantages such as high operating dynamic adsorption capacity and low cost preparation. It was also demonstrated that the developed nanocomposite is suitable for on-line monitoring of Hg0. It could be applied for the laboratory and field studies.

Methylmercury: existing recommendations; methods of analysing and interpreting the results; economic evaluation

The beneficial effects of fish consumption are well- known. Nevertheless, there is worldwide concern regard methylmercury concentrations in fish, which is why many countries such as the United States, Australia, New Zealand, Canada and numerous European countries have made fish consumption recommendations for their populations, particularly vulnerable groups, in order to México methylmercury intake. Blood and hair are the best biological samples for measuring methylmercury. The most widely-used method to analyse methylmercury is cold vapor atomic absorption spectrometry, although there are also direct methods based on the thermal decomposition of the sample. In recent years, the number of laboratories that measure mercury by inductively coupled plasma mass spectrometry has increased. In addition, the different kinds of mercury can be distinguished by coupling chromatography methods of separation. Laboratories that analyse mercury in biological samples need to participate in external quality control programmes. Even if mercury emissions are reduced, mercury may remain in the environment for many years, so dietary recommendations are fundamental in order to reduce exposure. It is necessary to propose public health measures aimed at decreasing mercury exposure and to evaluate the benefits of such measures from the economic and social standpoints.