Boron accumulates in plants with the same isotopic ratio as found in the source soil and water, producing isotope ratios (11B/10B) that reflect those of the sources, thus indicating the provenance of products derived from vegetative matter. We developed and validated a simple analytical method based on gas collision inductively coupled plasma quadrupole mass spectrometry (ICP-QMS) for the determination of B isotope ratios to distinguish the geographic origins of wines. Use of the gas collision technique (using Ne as the collision gas) in ICP-QMS can effectively improve the precision and accuracy of 11B/10B determination, which may be due to improvement of the ion transmission or sensitivity (via collisional focusing) and a reduction in plasma noise (via collisional energy damping). Compared with the conventional method (without Ne gas collision), the precision of the 11B/10B ratio was improved 3.2-fold (from 3.15‰ to 0.94‰) and the accuracy was improved from an error of −5.5% to −0.1%. The −0.1% error represents mass bias, resulting from in-cell gas collision, and can be accurately corrected using an external bracketing technique with NIST SRM-951 B isotope standard. Direct dilution of the wines by a factor of 100 with 1% HNO3 was found to substantially reduce matrix-induced mass discrimination. Other important parameters such as detector dead time, dwell time per data acquisition, and total integration time per isotope were also optimised. Twenty wines from nine countries were analysed, and δ11B values ranged from +1.73 to +46.6‰ with an average external precision (N = 5) of 0.82–1.63‰. The proposed method has sufficient precision to distinguish between 20 wine brands originating from four different geographic regions.

•Fe(OH)3 co-precipitation aerosol dilution ICP-MS method developed for REE analysis•Over 93% of matrix elements were removed by the Fe(OH)3 co-precipitation procedure.•The target REEs were concentrated 15-fold by this precipitation procedure.•Online aerosol dilution technique decreased the rates of interfered oxide by up to 10-fold.•The residual matrix effects were effectively reduced by this dilution technique.Analysis data of rare earth elements (REEs) in high-salt groundwater can potentially provide a series of geochemical indicators. Accurate determination of sub-ng L− 1 levels of REEs by inductively coupled plasma-mass spectrometry (ICP-MS) is still a challenge because of low concentrations, significant matrix effects from the highly dissolved salts, and mass spectral interferences. A reliable method, based on online aerosol dilution ICP-MS after co-precipitation with Fe(OH)3, was evaluated for the determination of REEs in high-salt groundwater. First, an Fe(OH)3 co-precipitation procedure effectively separated the target REEs from the high-content matrix elements (i.e. K, Na, Ca, and Mg); over 93% of the matrix elements were removed and target REEs were concentrated 15-fold. Secondly, using the proposed online aerosol dilution technique resulted in diminished residual matrix effects and the reduction of mass spectral interferences from oxide ions (i.e. Ba and light REE-oxides) by up to 10-fold. The detection limits of the method ranged from 0.05 ng L− 1 for Lu to 0.6 ng L− 1 for Nd, with the REE recoveries between 90% and 125%. The results for a seawater standard reference material (NASS-6) agreed with literature reported values. The proposed method was employed for the analysis of five high-salt groundwater samples. The accurate results showed that this method has great potential for the determination of ultra-trace levels of REEs in various high-salt water samples.

The determination of cadmium (Cd) in geological samples by inductively coupled plasma mass spectrometry (ICP-MS) suffers from significant Mo and/or Zr based oxide interference. We have developed a valid method for Cd determination using Ar aerosol dilution ICP-MS after extraction with inverse aqua regia. Over 90% of the Zr was removed in the extraction procedure, and the residual Zr-hydroxides and Mo-oxides or hydroxides were successfully eliminated by adding an amount of Ar to the sample aerosol prior to the plasma. Compared to the conventional mode without adding Ar, the amount of oxide and hydroxide ions formed in the plasma was reduced by up to 90%. The relative yields of the interfering oxides and hydroxides were as low as 0.005% (MoOH/Mo or MoO/Mo) and 0.007% (ZrOH/Zr). Under the optimized dilution gas flow rate (0.85 L min−1) and carrier gas flow rate (0.24 L min−1), the limit of detection (LOD, 3σ) for 111Cd was 1.6 ng g−1. The proposed method was applied to the determination of Cd in 81 soil, sediment, and rock standard reference materials (SRMs). The results for 68 of these geological SRMs were in good agreement with the reference values. The Cd levels in 10 limestone SRMs (GSR-22, GSR-23, GSR-24, GSR-27, GSR-28, GUI-1, GUI-2, DIAN-1, DIAN-2, and DIAN-3) were reported for the first time, and reference Cd values for other 3 geological SRMs (GSD-7, GSD-19, and GSM-1) were updated by this method. The results showed that this method has great potential for Cd determination in geological samples.

Direct determination of sub-ng g−1 levels of gold by inductively coupled plasma mass spectrometry (ICP-MS) is complicated because of the presence of serious mass interferences, and the high first ionisation energy of Au (9.225 eV) also results in poor analytical sensitivity. A reliable method based on the combination of ion molecule reaction (IMR) ICP-MS and addition of a CH4 plasma modifier technique was evaluated for the direct determination of Au in geological samples. The interfering 181Ta16O+ and 180Hf16OH+ (the sample matrix source) on the mono-isotope 197Au were successfully eliminated by oxidation using O2 as the reaction gas. The deduced IMR mechanism in the reaction cell involved the oxidation of 197TaO+ and 197HfOH+ to the higher oxides 213TaO2+ and 213HfO2H+, 229TaO3+ and 229HfO3H+, and 245TaO4+ and 245HfO4H+, while the target Au does not react with O2. In addition, to further improve the method's signal to background ratio (SBR), a CH4 modifier was introduced to the ICP plasma at 2 mL min−1; the poor sensitivity of Au+ was increased by a factor of four and the background signal (at m/z 197) was decreased to 50%. The improvement of the SBR (eight fold) was due to both the carbon enhancement effect (for Au) and the carbon competition effect (with the interfering oxide ions) in the CH4 modified plasma. The proposed method was applied to the direct determination of Au in ten different types of geological standard reference materials (SRMs). The results of all SRMs were found to agree well with the certified values. This method has great potential for the direct determination of trace levels of Au in various geological samples.

Trace Pb is accumulated in the same isotopic ratio as it occurs in the source soil, and the isotopic composition of Pb could be used to reflect these sources and provide powerful indicators of the geographic origin of agricultural products. In this study, we developed a simple and valid method based on inductively coupled plasma dynamic reaction cell mass spectrometry (ICP-DRC-MS) for the determination of Pb isotope ratios to distinguish between the geographic origins of cigarettes. The cigarette digestion solutions were directly analysed by ICP-DRC-MS with pressuring a non-reactive gas Ne. In the DRC, Ne molecules collide with Pb ions and result in a 2.4-fold improvement in the average internal precision of Pb isotope ratios, which may be due to the improvement of the ion transmission or sensitivity (via collisional focusing) and the reduction of the plasma noise (via collisional energy damping). Under an optimum DRC rejection parameter q (RPq = 0.45), the main matrix components (K, Na, Ca, Mg, Al, Fe, etc.) originating from cigarettes were filtered out. Other important parameters such as detector dead time, dwell time per data acquisition and total integrated time per isotope were also optimized. Mass discrimination of the 208Pb/206Pb ratio in Ne DRC mode increased to 0.3% compared to the vented mode; this mass bias could be accurately corrected by using the NIST 981 Pb isotope standard solution. The accuracy and precision of this method were evaluated by using two cigarette reference materials (Oriental tobacco leaves CTA-OTL-1 and Virginia tobacco leaves CTA-VTL-2). The results of 208Pb/206Pb and 207Pb/206Pb were 2.0842 ± 0.0028 (2δ) and 0.8452 ± 0.0011 (2δ) for CTA-VTL-2, which were in agreement with the literature values (208Pb/206Pb = 2.0884 ± 0.0090 and 207Pb/206Pb = 0.8442 ± 0.0032), respectively. The Pb isotopic composition (208Pb/206Pb = 2.0812 ± 0.0028 and 207Pb/206Pb = 0.8460 ± 0.0018) of CTA-VTL-1 was reported for the first time in our study. The precision of Pb isotope ratios (208Pb/206Pb and 207Pb/206Pb) for the cigarette samples ranged from 0.05 to 0.12 % (N = 6). The proposed method has sufficient precision to distinguish between 91 cigarette brands that originated from four different geographic regions.

Cadmium (Cd) is an important element for the assessment of environmental pollution. An accurate and high throughput method involving slurry sampling electrothermal atomic absorption spectrometry (ETAAS) was developed to detect trace Cd content in geological samples. After sonication of the sample with 0.5% v/v HNO3 and 0.5% v/v Triton X-100 solution, the slurry was directly introduced into a graphite atomizer and detected by AAS. This simple method was shown to take 80% less time, and resulted in 90% less reagent waste than the conventional acid digestion method. Under optimized conditions (sample size ≤ 75 μm, sonication time: 20 min, pyrolysis temperature: 450 °C, and atomization temperature: 1600 °C), the characteristic mass and limit of detection for Cd were 0.8 pg and 0.002 μg g−1, respectively. The proposed method was applied to the determination of Cd in 86 soil, sediment, and rock standard reference materials (SRMs). The results for 78 of these materials were in good agreement with the reference values. The Cd levels in five limestone SRMs (GUI-1, GUI-2, DIAN-1, DIAN-2, and DIAN-3) and one clay SRM (GBW03103) were reported for the first time. The proposed method shows great potential for the direct determination of trace Cd in various geological samples.

A simple and high throughput method involving heat-extraction electrothermal atomic absorption spectrometry was developed to monitor the Cd content in rice, and 184 rice samples purchased from supermarkets in Beijing were surveyed. The main advantages of using heat-extraction in comparison to slurry sampling are doubling of the graphite tube lifetime and 80% decrease in the background absorbance signal, most likely because the less sample matrix was introduced into the atomizer, avoiding buildup of carbonaceous residues or silicates on the graphite platform. Heat-extraction provides better detection limits and precision than microwave acid digestion. In the heat-extraction method, slurries in 3% v/v HNO3 were heated on a heating block. After centrifugation, the supernatant was introduced into a graphite tube pretreated with a W–Rh permanent modifier. The optimum conditions for Cd detection were 0.2–5.0% m/v slurry concentration, 3% HNO3 extract, 10 min heating at 120 °C, rice-particle size <150 μm (after 3 min of sample grinding), 600 °C pyrolysis temperature, and 1500 °C atomization temperature. The extraction recovery for Cd in rice standard reference materials was 98.4–101.1%. The characteristic masses and detection limit for Cd based on the integrated absorbance for a 2.5% m/v rice sample were 0.7 ± 0.1 pg and 1 ng g−1, respectively. The mean Cd content was 0.076 μg g−1 (ranging from 0.004 to 0.876 μg g−1), and only 4.3% of investigated rice samples exceeded the maximum allowable Cd concentration of 0.20 μg g−1. This simple and rapid method has great potential for monitoring trace Cd in food samples for market survey.

Selenium can be emitted to the environment during the combustion of Se-rich stone coal, both polluting the air and wasting a scarce resource of Se. In this work, the nanosized metal oxides ZnO, Al2O3, and Fe3O4 were combined with CaO to form composite materials. These were investigated as sorbents for the removal of Se from the flue gases generated by Se-rich stone coal combustion over the temperature range of 700–1000 °C during laboratory scale testing. It was found that these composite materials, especially those containing ZnO and Fe3O4, exhibited higher adsorption efficiency than pure CaO. The highest adsorption efficiency of 95.46% was obtained with the CaO-ZnO composite sorbent under optimized experimental conditions. FT-IR and X-ray diffraction results indicated that the adsorbed Se was predominantly in the form of CaSeO3, with a minor amount of ZnSeO3. Both the formation of ZnSeO3 and the enhanced reaction interface contribute to the higher adsorption of Se on the CaO-ZnO composite sorbent as compared with pure CaO. These newly developed CaO-ZnO composite materials show potential as sorbents for the capture and recovery of Se during industrial-scale Se-rich stone coal combustion.

A robust method for trace element determination in food samples by addition of methane to the plasma of a dynamic reaction cell mass spectrometer (CH4 mixed plasma-DRC-MS) was developed. Addition of 3 mL min−1 methane to Ar-plasma eliminates the signal suppressions of various elements (As, Se, Hg, etc.) due to the high concentration of nitric acid (10%, v/v). The CH4–Ar mixed plasma may compensate for the plasma cooling effects due to the highly concentrated nitric acid. The interfering polyatomic ions 40Ar12C+, 40Ar35Cl+ and 40Ar40Ar+ on 52Cr+, 75As+ and 80Se+ determination were removed effectively using the DRC with CH4 as the reaction gas. The limits of quantification (LOQ, 10σ) were 0.35 ng g−1, 0.07 ng g−1, 0.35 ng g−1, 0.07 ng g−1, 0.15 ng g−1, and 0.07 ng g−1 for As, Cd, Cr, Hg, Pb and Se, respectively. The proposed method was applied to the determination of these trace elements in four food standard reference materials (NIST1577b, GBW10018, NIST1570a and GBW10016), and the results were in good agreement with the certified values.Highlights► Addition of methane to Ar-plasma can eliminate the acid effects in ICP-MS. ► Polyatomic interferences on Cr, As and Se were removed by CH4 as the DRC gas. ► The valid method has great potential for the trace elements in various food samples.

Mercury is subject to severe tungsten oxide (WO) interference in the direct ICP-MS analysis for soil or sediment samples. In this study, a method based on ion molecule reaction (IMR) was used to eliminate the WO spectral interference in a dynamic reaction cell (DRC). Interfered ion (202WO+) was drastically oxidized to higher oxide ions (218WO2+ or 234WO3+) by O2 as the reaction gas in the DRC, while the analyte ion (202Hg+) cannot react with O2. Under the optimized O2 flow rate (1.9 mL min−1) and DRC rejection parameter q (Rpq, 0.80), the background signal was reduced by up to 1000-fold at m/z 202 and the limit of quantitation (LOQ, 10σ) for 202Hg was 1 ng g−1. The proposed method was applied to direct determination of Hg in a series of soil and sediment standard reference materials (SRMs) and the satisfactory results indicate that it has great potential for the determination of trace or ultra-trace level mercury in various environmental or geological samples.

Trace levels of arsenic (As) in soil samples can be determined by conventional ICP-QMS with closed vessel digestion, but always suffer from interference of ions originating from the complicated matrix, mainly including 40Ca35Cl+, 40Ar35Cl+, 39K36Ar+, 150Nd2+, 150Eu2+ and 150Sm2+etc. In this study, 75As+, the mass for general detection, was effectively changed to 75As16O+ which could be detected at m/z 91 by reaction with oxygen in a Dynamic Reaction Cell (DRC). For the new interference of 91Zr+ on 75As16O+, boiling aqua regia extraction was used to remove most of the zirconium in the sample preparation procedure, and the residual 91Zr+ was oxidized to 91Zr16O+ by oxygen in the DRC. In addition, the signal intensity of 75As16O was improved 4-fold by addition of 4% methanol into the sample solution. The signal to background ratio (SBR) of As was obviously improved from 0.18 to 205 (the certified arsenic concentration is 1 μg L−1), and a limit of quantification (LOQ, 10σ) of 0.1 ng g−1 was obtained. The proposed method was successfully applied to analyze 20 soil samples collected from pig farms in livestock farming processes, and shows its great potential for trace As determination in environmental and geological samples.

A novel, fast and simple non-chromatographic approach for determination of inorganic and total mercury has been developed by cold vapor atomic absorption spectrometry based on dielectric barrier discharge (DBD) atomizer. The determination of inorganic mercury and total mercury can be achieved in a fast sequential fashion (1 min sample−1). In the proposed method, with 0.01% (m/v) NaBH4 used as reductant, inorganic mercury is reduced to elemental mercury, whereas the methylmercury forms an intermediate volatile methylmercury hydride (CH3HgH). A low temperature DBD atomizer was employed for the atomization of CH3HgH. Only inorganic mercury can be measured in the absence of the DBD plasma. However, in addition to inorganic mercury, CH3HgH can be atomized and total mercury is determined in the presence of the plasma. The methylmercury concentration can then be obtained from the difference. The effects of several experimental parameters, such as NaBH4 concentration, HCl concentration, discharge gas and gas flow rate on the analytical performance were investigated. The method provided good reproducibility (<3% RSD) and the detection limits of Hg2+ and CH3Hg+ were found to be 0.35 ng mL−1 and 0.54 ng mL−1, respectively. The proposed method was validated by the analysis of a certified reference material (tuna fish). In addition, it was successfully applied to the analysis of fish samples. The method is excellent for mercury speciation measurements as it provides short analysis time and good reproducibility.

Mercury is subject to severe tungsten oxide (WO) interference in the direct ICP-MS analysis for soil or sediment samples. In this study, a method based on ion molecule reaction (IMR) was used to eliminate the WO spectral interference in a dynamic reaction cell (DRC). Interfered ion (202WO+) was drastically oxidized to higher oxide ions (218WO2+ or 234WO3+) by O2 as the reaction gas in the DRC, while the analyte ion (202Hg+) cannot react with O2. Under the optimized O2 flow rate (1.9 mL min−1) and DRC rejection parameter q (Rpq, 0.80), the background signal was reduced by up to 1000-fold at m/z 202 and the limit of quantitation (LOQ, 10σ) for 202Hg was 1 ng g−1. The proposed method was applied to direct determination of Hg in a series of soil and sediment standard reference materials (SRMs) and the satisfactory results indicate that it has great potential for the determination of trace or ultra-trace level mercury in various environmental or geological samples.

Trace levels of arsenic (As) in soil samples can be determined by conventional ICP-QMS with closed vessel digestion, but always suffer from interference of ions originating from the complicated matrix, mainly including 40Ca35Cl+, 40Ar35Cl+, 39K36Ar+, 150Nd2+, 150Eu2+ and 150Sm2+etc. In this study, 75As+, the mass for general detection, was effectively changed to 75As16O+ which could be detected at m/z 91 by reaction with oxygen in a Dynamic Reaction Cell (DRC). For the new interference of 91Zr+ on 75As16O+, boiling aqua regia extraction was used to remove most of the zirconium in the sample preparation procedure, and the residual 91Zr+ was oxidized to 91Zr16O+ by oxygen in the DRC. In addition, the signal intensity of 75As16O was improved 4-fold by addition of 4% methanol into the sample solution. The signal to background ratio (SBR) of As was obviously improved from 0.18 to 205 (the certified arsenic concentration is 1 μg L−1), and a limit of quantification (LOQ, 10σ) of 0.1 ng g−1 was obtained. The proposed method was successfully applied to analyze 20 soil samples collected from pig farms in livestock farming processes, and shows its great potential for trace As determination in environmental and geological samples.

Trace Pb is accumulated in the same isotopic ratio as it occurs in the source soil, and the isotopic composition of Pb could be used to reflect these sources and provide powerful indicators of the geographic origin of agricultural products. In this study, we developed a simple and valid method based on inductively coupled plasma dynamic reaction cell mass spectrometry (ICP-DRC-MS) for the determination of Pb isotope ratios to distinguish between the geographic origins of cigarettes. The cigarette digestion solutions were directly analysed by ICP-DRC-MS with pressuring a non-reactive gas Ne. In the DRC, Ne molecules collide with Pb ions and result in a 2.4-fold improvement in the average internal precision of Pb isotope ratios, which may be due to the improvement of the ion transmission or sensitivity (via collisional focusing) and the reduction of the plasma noise (via collisional energy damping). Under an optimum DRC rejection parameter q (RPq = 0.45), the main matrix components (K, Na, Ca, Mg, Al, Fe, etc.) originating from cigarettes were filtered out. Other important parameters such as detector dead time, dwell time per data acquisition and total integrated time per isotope were also optimized. Mass discrimination of the 208Pb/206Pb ratio in Ne DRC mode increased to 0.3% compared to the vented mode; this mass bias could be accurately corrected by using the NIST 981 Pb isotope standard solution. The accuracy and precision of this method were evaluated by using two cigarette reference materials (Oriental tobacco leaves CTA-OTL-1 and Virginia tobacco leaves CTA-VTL-2). The results of 208Pb/206Pb and 207Pb/206Pb were 2.0842 ± 0.0028 (2δ) and 0.8452 ± 0.0011 (2δ) for CTA-VTL-2, which were in agreement with the literature values (208Pb/206Pb = 2.0884 ± 0.0090 and 207Pb/206Pb = 0.8442 ± 0.0032), respectively. The Pb isotopic composition (208Pb/206Pb = 2.0812 ± 0.0028 and 207Pb/206Pb = 0.8460 ± 0.0018) of CTA-VTL-1 was reported for the first time in our study. The precision of Pb isotope ratios (208Pb/206Pb and 207Pb/206Pb) for the cigarette samples ranged from 0.05 to 0.12 % (N = 6). The proposed method has sufficient precision to distinguish between 91 cigarette brands that originated from four different geographic regions.

A novel, fast and simple non-chromatographic approach for determination of inorganic and total mercury has been developed by cold vapor atomic absorption spectrometry based on dielectric barrier discharge (DBD) atomizer. The determination of inorganic mercury and total mercury can be achieved in a fast sequential fashion (1 min sample−1). In the proposed method, with 0.01% (m/v) NaBH4 used as reductant, inorganic mercury is reduced to elemental mercury, whereas the methylmercury forms an intermediate volatile methylmercury hydride (CH3HgH). A low temperature DBD atomizer was employed for the atomization of CH3HgH. Only inorganic mercury can be measured in the absence of the DBD plasma. However, in addition to inorganic mercury, CH3HgH can be atomized and total mercury is determined in the presence of the plasma. The methylmercury concentration can then be obtained from the difference. The effects of several experimental parameters, such as NaBH4 concentration, HCl concentration, discharge gas and gas flow rate on the analytical performance were investigated. The method provided good reproducibility (<3% RSD) and the detection limits of Hg2+ and CH3Hg+ were found to be 0.35 ng mL−1 and 0.54 ng mL−1, respectively. The proposed method was validated by the analysis of a certified reference material (tuna fish). In addition, it was successfully applied to the analysis of fish samples. The method is excellent for mercury speciation measurements as it provides short analysis time and good reproducibility.

Cadmium (Cd) is an important element for the assessment of environmental pollution. An accurate and high throughput method involving slurry sampling electrothermal atomic absorption spectrometry (ETAAS) was developed to detect trace Cd content in geological samples. After sonication of the sample with 0.5% v/v HNO3 and 0.5% v/v Triton X-100 solution, the slurry was directly introduced into a graphite atomizer and detected by AAS. This simple method was shown to take 80% less time, and resulted in 90% less reagent waste than the conventional acid digestion method. Under optimized conditions (sample size ≤ 75 μm, sonication time: 20 min, pyrolysis temperature: 450 °C, and atomization temperature: 1600 °C), the characteristic mass and limit of detection for Cd were 0.8 pg and 0.002 μg g−1, respectively. The proposed method was applied to the determination of Cd in 86 soil, sediment, and rock standard reference materials (SRMs). The results for 78 of these materials were in good agreement with the reference values. The Cd levels in five limestone SRMs (GUI-1, GUI-2, DIAN-1, DIAN-2, and DIAN-3) and one clay SRM (GBW03103) were reported for the first time. The proposed method shows great potential for the direct determination of trace Cd in various geological samples.

The determination of cadmium (Cd) in geological samples by inductively coupled plasma mass spectrometry (ICP-MS) suffers from significant Mo and/or Zr based oxide interference. We have developed a valid method for Cd determination using Ar aerosol dilution ICP-MS after extraction with inverse aqua regia. Over 90% of the Zr was removed in the extraction procedure, and the residual Zr-hydroxides and Mo-oxides or hydroxides were successfully eliminated by adding an amount of Ar to the sample aerosol prior to the plasma. Compared to the conventional mode without adding Ar, the amount of oxide and hydroxide ions formed in the plasma was reduced by up to 90%. The relative yields of the interfering oxides and hydroxides were as low as 0.005% (MoOH/Mo or MoO/Mo) and 0.007% (ZrOH/Zr). Under the optimized dilution gas flow rate (0.85 L min−1) and carrier gas flow rate (0.24 L min−1), the limit of detection (LOD, 3σ) for 111Cd was 1.6 ng g−1. The proposed method was applied to the determination of Cd in 81 soil, sediment, and rock standard reference materials (SRMs). The results for 68 of these geological SRMs were in good agreement with the reference values. The Cd levels in 10 limestone SRMs (GSR-22, GSR-23, GSR-24, GSR-27, GSR-28, GUI-1, GUI-2, DIAN-1, DIAN-2, and DIAN-3) were reported for the first time, and reference Cd values for other 3 geological SRMs (GSD-7, GSD-19, and GSM-1) were updated by this method. The results showed that this method has great potential for Cd determination in geological samples.

A simple and high throughput method involving heat-extraction electrothermal atomic absorption spectrometry was developed to monitor the Cd content in rice, and 184 rice samples purchased from supermarkets in Beijing were surveyed. The main advantages of using heat-extraction in comparison to slurry sampling are doubling of the graphite tube lifetime and 80% decrease in the background absorbance signal, most likely because the less sample matrix was introduced into the atomizer, avoiding buildup of carbonaceous residues or silicates on the graphite platform. Heat-extraction provides better detection limits and precision than microwave acid digestion. In the heat-extraction method, slurries in 3% v/v HNO3 were heated on a heating block. After centrifugation, the supernatant was introduced into a graphite tube pretreated with a W–Rh permanent modifier. The optimum conditions for Cd detection were 0.2–5.0% m/v slurry concentration, 3% HNO3 extract, 10 min heating at 120 °C, rice-particle size <150 μm (after 3 min of sample grinding), 600 °C pyrolysis temperature, and 1500 °C atomization temperature. The extraction recovery for Cd in rice standard reference materials was 98.4–101.1%. The characteristic masses and detection limit for Cd based on the integrated absorbance for a 2.5% m/v rice sample were 0.7 ± 0.1 pg and 1 ng g−1, respectively. The mean Cd content was 0.076 μg g−1 (ranging from 0.004 to 0.876 μg g−1), and only 4.3% of investigated rice samples exceeded the maximum allowable Cd concentration of 0.20 μg g−1. This simple and rapid method has great potential for monitoring trace Cd in food samples for market survey.