Analysis of food for toxic elements

Potential toxic elements in breakfast cereals in the Kurdistan region, Iraq

Potential toxic elements are substances that can accumulate in foodstuffs and pose risks to human health even at low levels, or when their levels exceed safety thresholds. A total of 78 breakfast cereals were purchased from the Kurdistan region, Iraq. Their PTE levels were analysed and associated health risks were calculated. The levels of As, Cd, Pb, Cu and Cr ranged from 0.055 ± 0.02-0.12 ± 0.05 mg/kg, 0.024 ± 0.009-0.08 ± 0.03 mg/kg, 0.015 ± 0.003-0.12 ± 0.06 mg/kg, 1.93 ± 0.5-3.9 ± 0.1 mg/kg and 0.36 ± 0.02-0.84 ± 0.1 mg/kg, respectively. The PTE levels were mostly below the Codex Alimentarius maximum limits, except in 11 samples, which exceeded the limits for As, Cd and Pb. Risk assessment data of HQ and HI (below 1) showed no non-carcinogenic health risks for both adults and children. However, due to the high levels of As, Cd and Pb in some samples, continuous monitoring is advisable to ensure the constant quality of these products.

Mercury Determination in Certifiable Color Additives Using Thermal Decomposition Amalgamation and Atomic Absorption Spectrometric Analysis

BACKGROUND

Color additives requiring batch certification by the U.S. Food and Drug Administration (FDA) have Code of Federal Regulations (CFR) specification limits for certain elements and are usually analyzed by x-ray fluorescence spectrometry (XRF). However, sensitivity for Hg is too low in some color additives.

OBJECTIVE

The thermal decomposition amalgamation-atomic absorption spectrometric (TDA-AAS) technique was investigated for providing quick and accurate determinations of Hg in certifiable color additives.

METHODS

Tests were performed to optimize conditions and test reliability of Hg determinations at and below the CFR specification limit of 1 mg/kg.

RESULTS

Sensitivity is much improved over XRF with limits of quantitation of 0.03 mg/kg for highly homogeneous color additives.

CONCLUSIONS

The TDA-AAS method can be used for determining Hg concentrations at and below the CFR specification limit. The technique is effective for all color additives, including those that are difficult to analyze by XRF, but less efficient for color additives that quickly deteriorate the catalyst. Regular quality checks using certified reference materials and in-house matrix-matched check standards are essential.

HIGHLIGHTS

The TDA-AAS method is applicable for use in routine color additive batch certification. Certain matrices (notably those that release nitrogen or sulfur oxides or halogens upon combustion) necessitate more frequent replacement of the catalyst and recalibration, impacting productivity. Color additives containing BaSO4, in color additive lakes, that are difficult to analyze by other techniques are well suited for TDA-AAS analysis.

Trace Elements in Breakfast Cereals and Exposure Assessment in Moroccan Population: Case of Lead and Cadmium

The role of breakfast cereals in a balanced diet has been recognized for many years. Such foods should be safe and not contain toxic substances, especially trace elements. Among these elements, lead (Pb) and cadmium (Cd) are two important inorganic food contaminants. In this study, we assessed the contamination levels of breakfast cereal samples available in Morocco with Pb and Cd. For this, a total of sixty-two (n = 62) samples of breakfast cereals purchased in different markets in the country were surveyed for their Pb and Cd contents by using atomic absorption spectrophotometer (GF-AAS) after total mineralization of samples. Results showed that out of 62 total samples, 47 samples (75.8%) were contaminated with Pb concentrations in the range of 0.016-1.057 μg/g. The remaining samples (24.2%) were under the detection limit (LOD) of Pb. In the case of Cd, 41 samples (66.1%) were contaminated with Cd levels that ranged between 0.011 and 0.123 μg/g. In the present study, four samples (6.45%) of breakfast cereals are above the maximum limit (0.2 μg/g) set by the European Commission Regulation No 1881/2006 for Pb in cereals. However, for the Cd, only one sample exceeded the maximum limit set for this element (0.1 μg/g). The levels compare well with those reported worldwide for similar foodstuffs. The estimation of the provisional weekly intakes of the two elements (Pb and Cd) showed that the risks of development of toxicological effects through breakfast cereals are very low. However, it is important that the long-term exposure to these elements be kept to minimum. This is the first study on the co-occurrence of the two trace elements (Pb and Cd) in breakfast cereal samples commercialized in Morocco.

Selective electromembrane extraction and sensitive colorimetric detection of copper(II)

In this study, an extremely effective electromembrane extraction (EME) method was developed for the selective extraction of Cu(II) followed by Red-Green-Blue (RGB) detection. The effective parameters optimized for the extraction efficiency of EME include applied voltage, extraction time, supported liquid membrane (SLM) composition, pH of acceptor/donor phases, and stirring rate. Under optimized conditions, Cu(II) was extracted from a 3 mL aqueous donor phase to 8 µL of 100 mM HCl acceptor solution through 1-octanol SLM using an applied voltage of 50 V for 15 min. The proposed method provides a working range of 0.1–0.75 µg·mL−1 with 0.03 µg·mL−1 limit for detection. Finally, the developed technique was applied to different environmental water samples for monitoring environmental pollution. Obtained relative recoveries were within the range of 93–106%. The relative standard deviation (RSD) and enhancement factor (EF) were found to be ≤4.8% and 100 respectively. We hope that this method can be introduced for quantitative determination of Cu(II) as a fast, simple, portable, inexpensive, effective, and precise procedure.

Elemental metabolomics

Elemental metabolomics is quantification and characterization of total concentration of chemical elements in biological samples and monitoring of their changes. Recent advances in inductively coupled plasma mass spectrometry have enabled simultaneous measurement of concentrations of > 70 elements in biological samples. In living organisms, elements interact and compete with each other for absorption and molecular interactions. They also interact with proteins and nucleotide sequences. These interactions modulate enzymatic activities and are critical for many molecular and cellular functions. Testing for concentration of > 40 elements in blood, other bodily fluids and tissues is now in routine use in advanced medical laboratories. In this article, we define the basic concepts of elemental metabolomics, summarize standards and workflows, and propose minimum information for reporting the results of an elemental metabolomics experiment. Major statistical and informatics tools for elemental metabolomics are reviewed, and examples of applications are discussed. Elemental metabolomics is emerging as an important new technology with applications in medical diagnostics, nutrition, agriculture, food science, environmental science and multiplicity of other areas.

Human health risks due to heavy metals through consumption of wild mushrooms from Macheke forest, Rail Block forest and Muganyi communal lands in Zimbabwe

The levels and sources of toxic heavy metals in Amanita loosii (AL) and Cantharellus floridulus (CF) mushrooms and their substrates were studied in some parts of Zimbabwe, Rail Block forest (mining town), Macheke forest (commercial farming), and Muganyi communal lands. The mushrooms and their associated soils were acid digested prior to Al, Pb, and Zn determination by inductively coupled plasma optical emission spectroscopy. The transfer factors, mushrooms-soil metal correlation coefficients, daily intake rates, weekly intake rates, and target hazard quotients were calculated for each metal. The concentration of Zn, Al and Pb in mushrooms ranged from 1.045 ± 0.028 to 7.568 ± 0.322, 0.025 ± 0.001 to 0.654 ± 0.005, and a maximum of 5.78 ± 0.31 mg/kg, respectively, in all the three sampling areas. The mean heavy metal concentrations among the three sampling areas decreased as follows: Rail Block forest (mining town) > Macheke forest (commercial farming) > Muganyi communal lands for the concentrations in both mushrooms and total concentration in their substrates. C. floridulus accumulated higher concentrations of Al, Zn, and Pb than A. loosii at each site under study. Zn in both AL and CF (Muganyi communal lands) and Pb in AL (Rail Block forest) were absorbed only from the soils, while other sources of contamination were involved elsewhere. The consumption of 300 g of fresh A. loosii and C. floridulus per day by children less than 16 kg harvested from Rail Block forest would cause health problems, while mushrooms from Macheke Forest and Muganyi communal lands were found to be safe for human consumption. Due to non-biodegradability and bioaccumulation abilities of heavy metals, people are discouraged to consume A. loosii and C. floridulus from Rail Block forest for they have significant levels of heavy metals compared to those from Macheke forest and Muganyi communal lands.

Study of the migration phenomena of specific metals in canned tomato paste before and after opening. Validation of a new quality indicator for opened cans

A method for the simultaneous determination of Cd-Pb, As-Cu, Cr-Ni and Fe-Mn in canned tomato paste samples by Electrothermal Atomic Absorption Spectrometry was developed and validated. The validation procedure was conducted according to the terms of the European regulation for the official control of contaminants in foods. The validated method was applied for the determination of these metals and metalloids in 13 different tomato paste samples and the results showed that Cd content was higher than the maximum permissible value of 0.050 mg kg(-1) as proposed in European Regulation (EC) No 1881/2006 concerning fresh fruits and vegetables. Furthermore, a new quality indicator was evaluated in order to provide information about tomato paste quality and the appropriate storage time of an opened canned tomato paste. Finally, a migration test was accomplished based on the calculation of mass balance and the comparison of the elemental content in canned tomato paste samples and in aseptic paper pack and it was proved that Fe and Pb were the main metals migrating in tomato paste samples.

Cancer and non-cancer health effects from food contaminant exposures for children and adults in California: a risk assessment

BACKGROUND

In the absence of current cumulative dietary exposure assessments, this analysis was conducted to estimate exposure to multiple dietary contaminants for children, who are more vulnerable to toxic exposure than adults.

METHODS

We estimated exposure to multiple food contaminants based on dietary data from preschool-age children (2-4 years, n=207), school-age children (5-7 years, n=157), parents of young children (n=446), and older adults (n=149). We compared exposure estimates for eleven toxic compounds (acrylamide, arsenic, lead, mercury, chlorpyrifos, permethrin, endosulfan, dieldrin, chlordane, DDE, and dioxin) based on self-reported food frequency data by age group. To determine if cancer and non-cancer benchmark levels were exceeded, chemical levels in food were derived from publicly available databases including the Total Diet Study.

RESULTS

Cancer benchmark levels were exceeded by all children (100%) for arsenic, dieldrin, DDE, and dioxins. Non-cancer benchmarks were exceeded by >95% of preschool-age children for acrylamide and by 10% of preschool-age children for mercury. Preschool-age children had significantly higher estimated intakes of 6 of 11 compounds compared to school-age children (p<0.0001 to p=0.02). Based on self-reported dietary data, the greatest exposure to pesticides from foods included in this analysis were tomatoes, peaches, apples, peppers, grapes, lettuce, broccoli, strawberries, spinach, dairy, pears, green beans, and celery.

CONCLUSIONS

Dietary strategies to reduce exposure to toxic compounds for which cancer and non-cancer benchmarks are exceeded by children vary by compound. These strategies include consuming organically produced dairy and selected fruits and vegetables to reduce pesticide intake, consuming less animal foods (meat, dairy, and fish) to reduce intake of persistent organic pollutants and metals, and consuming lower quantities of chips, cereal, crackers, and other processed carbohydrate foods to reduce acrylamide intake.

Investigating the origin of tomatoes and triple concentrated tomato pastes through multielement determination by inductively coupled plasma mass spectrometry and statistical analysis

The concentration of 32 elements (Al, As, Ba, Be, Ca, Cd, Ce, Cu, Dy, Fe, K, La, Lu, Mg, Mn, Na, Nd, Pb, Rb, Sm, Sr, Th, U, V, Zn) was determined in tomatoes harvested in different four Italian regions and in triple concentrated tomato paste samples coming from Italy, China, Greece and California. The resulting multielement profiles were processed using three chemometric techniques to evaluate the possibility of discrimination between different cultivation areas. The closed-vessel microwave digested samples were diluted and analyzed by DRC-ICP-MS with CH(4) as reaction gas. The accuracy of the proposed method was considered acceptable (values in the range 75-120%) for 25 out of the 35 elements of the reference material NCS ZC85006 Tomato. The origin of tomato fruits and the areas of production as "Italy" and "non-Italy" of the triple concentrated pastes were evaluated by three supervised pattern recognition procedures, linear discriminant analysis (LDA), soft independent modeling of class analogy (SIMCA) and K-nearest neighbors (KNN).