Automated microwave digestion of certifiable color additives for determination of mercury by cold vapor atomic absorption spectrometry

A procedure using an automated microwave flow digestion technique was developed and validated for the digestion of samples of certifiable color additives before mercury determination by cold vapor atomic absorption spectrometry. Recovery studies were performed by spiking most of the color additives subject to batch certification by the U.S. Food and Drug Administration with inorganic mercury (HgNO3) and with organic mercury (CH3HgCl). Successful recoveries of 72-113% Hg added at the 1 microg/g level were obtained. A method detection limit of 0.2 microg Hg/g was estimated from a Hg-spiked FD&C Yellow No. 6 sample. At the specification level of 1 ppm Hg (1 microg Hg/g), the 95% confidence interval was +/- 0.2 ppm (0.2 microg Hg/g).     

Speciation of metal-EDTA complexes by flow injection analysis with electrospray ionization mass spectrometry and ion chromatography with inductively coupled plasma mass spectrometry

Flow injection analysis (FIA) with ESI-MS and ion chromatography (IC) with inductively coupled plasma-MS (ICP-MS) as the complementary technique have been explored for the determination of metal ions as their metal-EDTA complexes. ESI-MS enabled the identification of metal-EDTA complexes such as [Mn(EDTA)](2-), [Co(EDTA)](2-), [Ni(EDTA)](2-), [Cu(EDTA)](2-), [Zn(EDTA)](2-), [Pb(EDTA)](2-), and [Fe(EDTA)](1-) and their MS spectral showed that these metal-EDTA complexes were present in solution. Based on the ESI-MS, ion chromatographic separation and ICP-MS detection of these complexes are possible because IC-ICP-MS requires stable metal-EDTA complex during the chromatographic separation. The separation of these metal-EDTA complexes was achieved on an anion-exchange column with a mobile phase containing 30 mM NH(4)(HPO(4))(2) at pH 7.5 within 7 min with ICP-MS providing element specific detection. The ICP-MS LODs for the metal-EDTA were in the range of 0.1-0.5 microg/L with the exception of Fe (15 microg/L). The proposed method was a simple procedure for sample processing, using direct injection of sample without removal of sample matrix and was successfully applied to the determination of metal-EDTA complexes in real samples.     

Inductively coupled plasma mass spectrometric determination of molybdenum in urine

A method was developed for the determination of molybdenum (Mo) in human urine by direct dilution of the sample in doubly distilled water with 1% HNO3 (v/v) and inductively coupled mass spectrometry (ICP-MS). In and Y were used as internal standards. Since (98)Mo provides a higher sensitivity, it was chosen as the reference isotope. The influence of different factors, such as sample dilution, HNO3 concentration and the stability of the analyte were evaluated. The detection limit (LOD) was assessed at 0.2 microg/L Mo, while the lower limit of quantification (LOQ) was 0.6 microg/L. Recoveries ranged between 97.2 and 100.7% from solutions containing from 10 to 50 microg/L Mo. Linear calibration curves were generated from 2.1 and 52.1 microg/L with coefficients of variation (CV ) ranging from 1.62 to 3.56%. In order to establish reference values (RV) for molybdenum, the procedure presented here was used to determine Mo in the urine of a population group living in Tuscany, Italy.     

Microwave digestion methods for the determination of trace elements in brain and liver samples by inductively coupled plasma mass spectrometry

Two microwave digestion systems (open-focused and closed-pressurized) were tested for the mineralization of human brain and bovine liver (NIST SRM 1577a) as dissolution steps prior to the determination of 16 trace elements (Bi, Cd, Co, Cs, Cu, Fe, Hg, Mn, Mo, Pb, Rb, Sb, Sn, Sr, Tl, and Zn) by inductively coupled plasma mass spectrometry (ICP-MS). Digestion parameters (mass of sample, digestion mixture, and power/time steps) were optimized using temperature and pressure sensors. Digestions with the open-focused microwave system require larger volumes of conc. HNO(3) and 30% H(2)O(2) than digestions with the closed-pressurized system. Both systems produce correct results for the bovine liver samples. The concentrations obtained for the digests of the open-focused system tend to be less precise than the concentrations from the "closed-pressurized" digests. Because the "open-focused" digests must be diluted to 50 mL to bring the acid concentration to 0.7-2.0 mol/L required by the ICP-MS (closed-pressurized digests need to be diluted to only 20 mL), the detection limits for the system with the open-focused digestion are higher than for the system with the closed-pressurized digestor. The open-focused digestor cannot handle more than 150 mg brain tissue, whereas the closed-pressurized system can mineralize 470 mg. The latter method gave better results with brain tissue than the open-focused system. The preparation of brain tissue as reference material for the determination of trace elements in brain samples is described.     

Determination of As, Sb, Bi and Hg in water samples by flow-injection inductively coupled plasma mass spectrometry with an in-situ nebulizer/hydride generator

A simple and very inexpensive in-situ nebulizer/hydride generator was used with inductively coupled plasma mass spectrometry (ICP-MS) for the determination of As, Sb, Bi and Hg in water samples. The application of hydride generation ICP-MS alleviated the sensitivity problem of As, Sb, Bi and Hg determinations encountered when the conventional pneumatic nebulizer was used for sample introduction. The sample was introduced by flow injection to minimize the deposition of solids on the sampling orifice. The elements in the sample were reduced to the lower oxidation states with L-cysteine before being injected into the hydride generation system. This method has a detection limit of 0.003, 0.003, 0.017 and 0.17 ng ml⁻¹ for As, Bi, Sb and Hg, respectively. This method was applied to determine As, Sb, Bi and Hg in a CASS-3 nearshore seawater reference sample, a SLRS-2 riverine water reference sample and a tap water collected from National Sun Yat-Sen University. The concentrations of the elements were determined by standard addition method. The precision was better than 20% for most of the determinations.     

Analytical method for the quantitative determination of urinary ethylenethiourea by liquid chromatography/electrospray ionization tandem mass spectrometry

A direct, rapid and selective method for the quantitative determination of the ethylenethiourea (ETU) in human urine has been validated and is reported in the present study. It allows the accurate quantification of ETU in this complex matrix without the use of any internal standard as the sample cleanup is effective enough for the removal of interferences that could lead to ion suppression in the electrospray ionization (ESI) source. This simple and rapid purification system, based on the use of a Fluorosil phase of a BondElut column followed by a liquid-liquid extraction procedure, achieves mean extracted recoveries, assessed at three different concentrations (2.5, 10.0, and 25.0 microg/L), always more than 85%. High-performance liquid chromatography (HPLC) with positive ion tandem mass spectrometry, operating in selected multiple reaction monitoring (MRM) mode, is used to quantify ETU in human urine. The assay is linear over the range 0-50 microg/L, with a lower limit of quantification (LOQ) of 1.5 microg/L and a coefficient of variation (CV) of 8.9%. The lower limit of detection (LOD) is assessed at 0.5 microg/L. The overall precision and accuracy were determined on three different days. The values for within- and between-day precision are < or = 8.3 and 10.1%, respectively, and the accuracy is in the range 97-118%. The relative uncertainties for the LOQ and QC concentrations have been estimated to be 18 and 8%, respectively. The assay was applied to quantify ETU in human urine from growers that regularly handle ethylenebisdithiocarbamate pesticides in large crop plantations. The biological samples were collected at the start and end of the working day, and the ETU urine levels were found to vary between 1.9 and 8.2 microg/L.     

Iodine speciation in biological samples by capillary electrophoresis-inductively coupled plasma mass spectrometry.

A hyphenation of capillary electrophoresis (CE) to inductively coupled plasma mass spectrometry (ICP-MS) was employed for the speciation of iodine. The separation method used a buffer sandwich of phosphate (pH 2.3), NaOH, sodium dodecyl sulfate (SDS) and borate buffer (pH 8.3) for stacking, aiming at sufficient separation of iodide, iodate, thyroxine (T4) and triiodothyronine (T3). These four iodine species were separated within 15 min and subsequently detected during a pressure-driven detection step (baseline-separated) at 19.5, 29.1, 36.6 and 42.2 s. The detection limits were determined at 0.08 microg I/L (iodide), 0.3 microg I/L (iodate), 3.5 microg I/L (thyroxine) and 2.5 microg I/L (triiodothyronine). This method was applied on iodine speciation in human serum ("healthy" and after thyroid gland operation) and urine. The serum from the healthy person contained iodide (13 microg I/L), T4 (61 microg I/L) and T3 (7.5 microg I/L), whereas the serum from the thyroid-operated person lacked T3. As no "free" I-hormones are known in serum, the role of the thyroid hormone binding globulin (TBG) was investigated. We found that spiked T4 or T3 immediately bound to TBG. Investigations on human urine showed only a peak for iodide.     

Simultaneous determination of Hg(II) and alkylated Hg, Pb, and Sn species in human body fluids using SPME-GC/MS-MS

A GC/MS-MS method for the determination of Hg(II) and alkylated Hg, Pb, and Sn species in human urine is described. Separation and identification of the metal species are performed by capillary gas chromatography coupled with an ion-trap mass spectrometer with electron impact ionization in the tandem-MS mode. For sample preparation a very promising technique was applied that is based on a derivatization with sodium tetraethylborate followed by headspace solid phase microextraction (SPME). Operation of the used ion trap in the tandem-MS mode yields in improved detection limits because of a signal-to-noise ratio that is at least one order of magnitude better than in the MS mode. The detection limits in real matrices like urine are between 7 and 22 ng/L for all species investigated. Urinary levels of inorganic Hg in non-occupationally exposed persons with and without dental amalgam were found to be between 0.1 and 1.4 μg/L. A reference material (“ClinRep, Level I”) was used for quality assurance. Compared to the coupling of GC with ICP-MS (“inorganic” MS), the advantage of the proposed method using an “organic” MS is that (i) the species can be directly identified via their precursor and daughter ions and (ii) analysis can be performed with a commercially available hyphenated technique at moderate costs and needs no lab-made interfacing. Moreover, it offers a real multi-element/multi-species capability with low detection limits and a minimum of sample preparation.     

Determination of Mercury in Urine and Seawater by Flow Injection Vapor Generation Isotope Dilution Inductively Coupled Plasma Mass Spectrometry

A simple and inexpensive laboratory-built vapor generator was used with inductively coupled plasma mass spectrometry (ICP-MS) for the determination of mercury in urine and seawater samples. The applications of vapor generation ICP-MS alleviated the non-spectroscopic interferences and the sensitivity problem of mercury determination encountered when the conventional pneumatic nebulizer was used for sample introduction. The concentration of mercury was determined by isotope dilution method. The isotope ratio of mercury was calculated from the peak areas of each injection peak. The repeatability of the peak areas and isotope ratio determinations of seven consecutive injections of 1 ng mL^?1 Hg solution were 2.3% and 2.2%, respectively. This method has a detection limit of 0.07 ng mL^?1 for mercury. This method was applied to determine mercury in a CASS-3 nearshore seawater reference sample, NASS-4 open ocean seawater reference sample, NIST SRM 2670 freeze-dried urine reference sample and several urine and seawater samples collected from National Sun Yat-Sen University. The results for the reference samples agreed satisfactorily with the reference values. Results for other samples analyzed by the isotope dilution method and the method of standard additions agreed satisfactorily. Precision was better than 10% for most of the determinations.     

High-throughput determination of seven trace elements in food samples by inductively coupled plasma-mass spectrometry

A method was developed for high-throughput determinations of 7 elements in food samples, namely antimony (Sb), arsenic (As), cadmium (Cd), chromium (Cr), lead (Pb), mercury (Hg), and tin (Sn). The samples were digested by closed-vessel microwave-assisted digestion using concentrated nitric acid (HNO3) as the medium, followed by microwave- assisted evaporation to concentrate the sample solutions before dilution to the desired volume. The microwave-assisted evaporation procedure effectively reduced the final acid concentration to around 8% before analysis by inductively coupled plasma-mass spectrometry (ICP-MS). This reduction allows determination by ICP-MS to proceed without further sample dilution, which would affect the detection limit. The method was validated, and method recoveries for As, Cd, Cr, Pb, and Hg were within the certified ranges of the chosen certified reference materials. Recoveries of the 7 elements from spiked samples ranged from 93.1 to 103.6%. The standard uncertainties of precision for the 7 elements were between 3.1 and 4.3%. Interlaboratory comparison studies for As, Cd, and Pb gave z-scores ranging from -0.2 to 0.3.     

On-line hyphenation of capillary electrophoresis with flame-heated furnace atomic absorption spectrometry for trace mercury speciation

Capillary electrophoresis (CE) was directly interfaced to flame-heated furnace atomic absorption spectrometry (FHF-AAS) via a laboratory-made thermospray interface for nanoliter trace element speciation. The CE-FHF-AAS interface integrated the superiorities of stable CE separation, complete sample introduction, and continuous vaporization for AAS detection without the need of extra external heat sources and any post-column derivation steps. To demonstrate the usefulness of the developed hybrid technique for speciation analysis, three environmentally significant and toxic forms of methylmercury (MeHg), phenylmercury (PhHg), and inorganic mercury (Hg(II)) were taken as model analytes. Baseline separation of the three mercury species was achieved by CE in a 60 cm long x 75 microm inner diameter fused-silica capillary at 20 kV and using a mixture of 100 mM boric acid and 10% v/v methanol (pH 8.30) as running electrolyte. The precision (relative standard deviation, RSD, n = 7) of migration time, peak area and peak height for the mercury species at 500 microg x L(-1) (as Hg) level were in the range of 0.9-1.2%, 1.5-1.9%, and 1.4-2.0%, respectively. The detection limit (S/N = 3) of three mercury species was 3.0 +/- 0.15 pg (as Hg), corresponding to 50.8 +/- 2.4 microg x L(-1) (as Hg) for 60 nL sample injection, which was almost independent on specific mercury species. The developed hybrid technique was successfully applied to the speciation analysis of mercury in a certified reference material (DORM-2, dogfish muscle).     

Determination of arsenic species in marine samples by HPLC-ICP-MS.

Arsenic speciation analysis in marine samples was performed using high performance liquid chromatography (HPLC) with ICP-MS detection. The separation of eight arsenic species viz. arsenite (As(III)), monomethylarsonic acid (MMA), dimethylarsinic acid (DMA), arsenate (As(V)), arsenobetaine, trimethylarsine oxide (TMAO), arsenocholine and tetramethylarsonium ion (TeMAs) was achieved on a Shiseido Capcell Pak C18 column by using an isocratic eluent (pH 3.0), in which condition As(III) and MMA were co-eluted. The entire separation was accomplished in 15 min. The detection limits for 8 arsenic species by HPLC/ICP-MS were in the range of 0.02 - 0.10 microg L(-1) based on 3sigma of blank response (n=9). The precision was calculated to be 3.1-7.3% (RSD) for all eight species. The method then successfully applied to several marine samples e.g., oyster, scallop, fish, and shrimps. For the extraction of arsenic species from seafood products, the low power microwave digestion was employed. The extraction efficiency was in the range of 52.9 - 112.3%. Total arsenic concentrations were analyzed by using the microwave acid digestion. The total arsenics in the certified reference materials (DORM-2 and TORT-2) were analyzed and agreed with the certified values. The concentrations of arsenics in marine samples were in the range 6.6 - 35.1 microg g(-1).     

Microwave digestion methods for the determination of trace elements in brain and liver samples by inductively coupled plasma mass spectrometry

Two microwave digestion systems (open-focused and closed-pressurized) were tested for the mineralization of human brain and bovine liver (NIST SRM 1577a) as dissolution steps prior to the determination of 16 trace elements (Bi, Cd, Co, Cs, Cu, Fe, Hg, Mn, Mo, Pb, Rb, Sb, Sn, Sr, Tl, and Zn) by inductively coupled plasma mass spectrometry (ICP-MS). Digestion parameters (mass of sample, digestion mixture, and power/time steps) were optimized using temperature and pressure sensors. Digestions with the open-focused microwave system require larger volumes of conc. HNO₃ and 30% H₂O₂ than digestions with the closed-pressurized system. Both systems produce correct results for the bovine liver samples. The concentrations obtained for the digests of the open-focused system tend to be less precise than the concentrations from the closed-pressurized digests. Because the open-focused digests must be diluted to 50 mL to bring the acid concentration to 0.7–2.0 mol/L required by the ICP-MS (closed-pressurized digests need to be diluted to only 20 mL), the detection limits for the system with the open-focused digestion are higher than for the system with the closed-pressurized digestor. The open-focused digestor cannot handle more than 150 mg brain tissue, whereas the closed-pressurized system can mineralize 470 mg. The latter method gave better results with brain tissue than the open-focused system. The preparation of brain tissue as reference material for the determination of trace elements in brain samples is described.     

Simultaneous determination of t,t-muconic, S-phenylmercapturic and S-benzylmercapturic acids in urine by a rapid and sensitive liquid chromatography/electrospray tandem mass spectrometry method

We describe a rapid and sensitive high-performance liquid chromatography/electrospray tandem mass spectrometry (HPLC/ESI-MS/MS) method for simultaneous determination of the most relevant metabolites of benzene and toluene, t,t-muconic acid (t,t-MA), S-phenylmercapturic acid (S-PMA), and S-benzylmercapturic acid (S-BMA). Urine samples were purified before analysis by solid-phase microextraction (SPE) on SAX cartridges with 50 mg sorbent mass. The developed method fulfils all the standard requirements of precision and accuracy. Calibration curves were linear within the concentration range of the standards (0-80 microg/L(urine) for t,t-MA, and 0-25 microg/L(urine) for S-PMA and S-BMA), and had correlation coefficients > or =0.997. Limits of detection were 6.0 microg/L for t,t-MA, 0.3 microg/L for S-PMA, and 0.4 microg/L for S-BMA. The method was used to determine t,t-MA, S-PMA and S-BMA levels in urine of 31 gasoline-station workers, with personal monitoring data obtained from radial symmetry passive diffusive samplers. In the context of mean work-shift exposures of 75.9 microg/m(3) (range 9.4-220.2) for benzene and 331.9 microg/m(3) (78.2-932.1) for toluene, metabolite concentrations in end-of-shift urine samples ranged from 23.5-275.3 microg/g(creatinine) for t,t-MA, non-detectable to 0.9 microg/g(creatinine) for S-PMA, and 3.8-74.8 microg/g(creatinine) for S-BMA. No significant correlation was found between the environmental concentrations and urinary metabolites (p > 0.05 for all cases); the ratios of benzene metabolites could be influenced by exposure levels and co-exposure to xylenes and toluene. The high throughput of this procedure should facilitate exploration of the metabolic effects of benzene-related co-exposure to toluene and alkylbenzenes in large populations of subjects exposed to gasoline.     

Analysis of solid samples by ICP-mass spectrometry

Summary ICP-Mass spectrometry is typically used as a technique for very rapid multielement analysis at trace and ultra-trace levels of solutions by continuous sample aspiration and nebulization. However, ICP-MS is well suited to be used as a detector for other sample introduction devices. For the analysis of solid samples laser sampling and electrothermal vaporization accessories may be used as sample introduction devices for ICP-MS. Laser sampling permits the analysis of many different types of solid materials. For solid sampling ETV-ICP-MS analysis it is of advantage to reduce the sample to a fine powder prior to analysis. For automated analysis powders may be introduced as slurries into the graphite furnace by means of a slurry sampling device. Since appropriate certified solid reference materials are not always available for calibration, or since they are not certified for all analyte elements of interest, the analyses discussed in this contribution were performed semiquantitatively. The instrument response function was established using reference materials which were similar in their composition to the samples. The results of semiquantitative bulk analyses of glass (NIST 612) and geological material (USGS GXR-3) by laser sampling ICP-MS are in good agreement with the certified values. The concentrations of the analytes determined in the glass sample were in the range of 10 g/g to 80 g/g. The lowest analyte concentration in the geological sample was 0.4 g/g (Eu) and the highest was approximately 186 mg/g (Fe). The precision achieved was in the order of 5% to 15%. Laser sampling ICP-MS is not only suitable to bulk analysis but also to analyses where spatial information is required. As an example for such an application the determination of Pb in a wine bottle cork stopper is dicussed. The slurry sampling technique was used for the semiquantitative analysis of NIST coal reference samples by electrothermal vaporization ICP-MS. The accuracy achieved with this approach was within a factor of ±2 of the reference values.     

Single-step microwave digestion with HNO(3) alone for determination of trace elements in coal by ICP spectrometry

A microwave digestion method with HNO₃ alone was conducted at a temperature as high as 250 °C for determination of 19 trace elements (Li, Be, V, Cr, Mn, Co, Ni, Cu, Zn, Ga, As, Se, Rb, Sr, Cd, Cs, Ba, Hg, and Pb) in coal jointly by inductively coupled plasma optical emission spectrometry (ICP-OES), inductively coupled plasma mass spectrometry (ICP-MS), and flow injection ICP-MS (FI-ICP-MS). The validity of determination was assessed by using three standard coals, SRM 1632c, BCR 180, and SARM 19. It was found that the high-temperature digestion led to an extensive decomposition of the organic matrix and clay in coal, and no dissolved and solid carbon remained in the final solution after evaporation. Good recoveries were observed for all trace elements in three coals, with the exception of V, Rb, and Cs in high-ash SARM 19. Additionally, FI-ICP-MS combined with the present digestion without evaporation pretreatment was proved to be a rapid and efficient approach for determination of ultra-trace elements such as Se, Cd, and Hg in coal.     

Precise determination of boron in titanium by inductively coupled plasma mass spectrometry

A method was developed for the determination of boron in titanium by inductively coupled plasma mass spectrometry (ICP-MS). A commercially available PTFE sample introduction system, leading to the desired low detection limits for boron, was used. The method is suitable for the determination of boron concentrations down to about 1 μg g^?1 in the solid material. The influence of the internal standard on the precision was studied and beryllium was selected as the internal standard. For the titanium analysed (BCR reference material 090), the ICP-MS result agreed with those obtained using other techniques. Several bars of titanium reference material were supplied and a study of the homogeneity of boron in this material was made. Using analysis of variance on the results obtained for the different bars, the homogeneity of boron in the reference material could be estimated to be better than 2.1%.     

Multielement determination of cadmium and lead in urine by simultaneous electrothermal atomic absorption spectrometry with an end-capped graphite tube.

A method for the multielement determination of cadmium and lead in urine is proposed by simultaneous electrothermal atomic absorption spectrometry (SIMAAS) with an end-capped transversely heated graphite atomizer (EC-THGA). The best conditions for cadmium and lead determination were obtained in the presence of NH4H2PO4 as a chemical modifier, using 500 degrees C and 1800 degrees C as the pyrolysis and atomization temperatures, respectively. Urine samples were diluted 1 + 4 directly in autosampler cups with a mixture of 0.125% (w/v) Triton X-100 + 2.5% (v/v) HNO3 + 0.31% (w/v) NH4H2PO4. The optimized heating program was carried out in 57 s, and the instrument calibration was done with aqueous reference solutions. The use of EC-THGA increased the sensitivity of cadmium and lead by 14% and 25%, respectively. The detection limits (n = 20, 3delta) were 0.03 microg L(-1) (0.36 pg) for cadmium and 0.57 microg L(-1) (6.8 pg) for lead. The performance of EC-THGA was acceptable up to 500 heating cycles. The reliability of the entire procedure was checked with the analysis of a lyophilized urine certified reference material. The found concentrations were in agreement with the recommended values (95% confidence level).     

Determination of rare earth elements in urine by electrothermal vaporization inductively coupled plasma mass spectrometry

A method was developed for the determination of rare earth elements (REEs) in urine with electrothermal vaporization inductively coupled plasma mass spectrometry (ETV-ICPMS). The undiluted sample was directly injected into the graphite tube and trifluoromethane (Freon-23) was used as chemical modifier in order to reduce the vaporization temperature and the memory effect of most of the lanthanides. The detection limits were in the range 1-10 ng/L with relative standard deviation of 3-5% at concentration levels of 1microg/L, and less than 10-15% at 100 ng/L. Two different procedures, external calibration and a standard additions method, were evaluated to measure the concentration levels of lanthanides in the urine samples and the second procedure was considered to be the best choice for calibration in this work. The level of REEs in urine of 50 healthy volunteers was in the range 5-20 ng/L, above the detection limit of ETV-ICPMS.     

Determination of metals in marine species by microwave digestion and inductively coupled plasma mass spectrometry analysis

A microwave digestion method suitable for determination of multiple elements in marine species was developed, with the use of cold vapor atomic spectrometry for the detection of Hg, and inductively coupled plasma mass spectrometry for all of the other elements. An optimized reagent mixture composed of 2 ml of HNO₃, 2 ml of H₂O₂ and 0.3 ml of HF used in microwave digestion of about 0.15 g (dry weight) of sample was found to give the best overall recoveries of metals in two standard reference materials. In the oyster tissue standard reference material (SRM 1566b), recoveries of Na, Al, K, V, Co, Zn, Se, Sr, Ag, Cd, Ni, and Pb were between 90% and 110%; Mg, Mn, Fe, Cu, As, and Ba recoveries were between 85% and 90%; Hg recovery was 81%; and Ca recovery was 64%. In a dogfish certified reference material (DORM-2), the recoveries of Al, Cr, Mn, Se, and Hg were between 90% and 110%; Ni, Cu, Zn, and As recoveries were about 85%; and Fe recovery was 112%. Method detection limits of the elements were established. Metal concentrations in flounder, scup, and blue crab samples collected from coastal locations around Long Island and in the Hudson River estuary were determined.