Lead contamination in food consumed and produced in Brazil: Systematic review and meta-analysis

Appropriate supply of sulfur alleviates lead toxicity and stimulates its accumulation in hyperaccumulator Arabis alpina

Widespread lead (Pb) contamination of agricultural soils is a global issue stemming from human activities. The remediation of Pb-contaminated soils used for agricultural purposes is critically important to safeguard food crop safety. Despite the modulating effects of sulfur (S) on plant responses to toxic heavy metals, the ecological, physiological, and molecular mechanisms driving such modulation in the Pb hyperaccumulator Arabis alpina L. remain unclear. Here, we investigated the effects of five S concentrations (0, 50, 100, 150, and 200 mg kg-1) on A. alpina grown in Pb-contaminated soil from a lead-zinc mining area. Under S50 (i.e., 50 mg kg-1) and S100 treatments, the Pb concentration in both shoots and roots of A. alpina significantly decreased compared to the control (S0). Specifically, the S50 treatment significantly enhanced Pb accumulation, plant biomass, and plant height, indicating that low S applications facilitate Pb accumulation from the soil and alleviate Pb toxicity. Additionally, S50, S100, and S150 treatments significantly improved photosynthetic rate, stomatal conductance, and intercellular CO2 concentration in A. alpina. Transcriptomic analysis showed that S50 and S100 treatments increased the expression of the LHCA, LHCB, psa, and psb genes, which had a significant impact on photosynthetic efficiency. S50 and S100 boosted glutathione (GSH) levels in A. alpina roots, and the increased expression of GST gene enhanced tolerance to environmental stress. In summary, these results suggest that an appropriate supply of S (S50 and S100) not only alleviates Pb toxicity by enhancing plant biomass, height, photosynthetic features, and sulfur metabolites but also stimulates Pb accumulation in the hyperaccumulator A. alpina. Our study elucidated the specific concentrations of sulfur that optimally enhance both Pb accumulation and stress tolerance in the hyperaccumulator A. alpina, providing novel insights into the practical application of sulfur in phytoremediation strategies and advancing our understanding of the underlying molecular mechanisms.

Lead Levels in the Most Consumed Mexican Foods: First Monitoring Effort

Globally, there is growing concern over the presence of lead (Pb) in foods because it is a heavy metal with several toxic effects on human health. However, monitoring studies have not been conducted in Mexico. In this study, we estimated the concentrations of Pb in the most consumed foods and identified those that exceeded the maximum limits (MLs) for Pb in foods established by the International Standards. Based on the Mexican National Health and Nutrition Survey, 103 foods and beverages were selected and purchased in Mexico City retail stores and markets. Samples were analyzed twice using atomic absorption spectrophotometry. Values above the limit of quantification (0.0025 mg/kg) were considered to be detected. The percentage of detected values was 18%. The highest concentration was found in infant rice cereal (1.005 mg/kg), whole wheat bread (0.447 mg/kg), pre-cooked rice (0.276 mg/kg), black pepper (0.239 mg/kg), and turmeric (0.176 mg/kg). Among the foods with detected Pb, the levels in infant rice cereal, whole wheat bread, pre-cooked rice, and soy infant formula exceeded the MLs. The food groups with the highest percentages of exceeded MLs were baby foods (18%) and cereals (11%). Monitoring the concentration of contaminants in foods is essential for implementing food safety policies and protecting consumer health.

Essential and Toxic Elements in Infant Cereal in Brazil: Exposure Risk Assessment

Infant cereals, one of the first solid foods introduced to infants, have been reported to pose risks to human health because they contain toxic elements and an excess of essential elements. The objective of this study was to assess the cancer and non-cancer risk of exposure to essential and toxic elements in infant cereal in Brazil. In our analyses, we included data from 18 samples of infant cereals made from different raw materials and estimated the incremental lifetime cancer risks and non-cancer hazard quotients (HQs) for their consumption. Rice cereal is particularly concerning because it is immensely popular and usually contains high levels of inorganic arsenic. In addition to arsenic, we assessed aluminum, boron, barium, cadmium, chromium, copper, lead, manganese, nickel, selenium, silver, strontium, and zinc. The cancer risk was highest for rice cereal, which was also found to have an HQ > 1 for most of the tested elements. Inorganic As was the element associated with the highest cancer risk in infant cereal. All of the infant cereals included in this research contained at least one element with an HQ > 1. The essential and non-essential elements that presented HQ > 1 more frequently were zinc and cadmium, respectively. The cancer and non-cancer risks could potentially be decreased by reducing the amount of toxic and essential elements (when in excess), and public policies could have a positive influence on risk management in this complex scenario.

Concentration of potentially harmful elements (PHEs) in eggplant vegetable (Solanum melongena) irrigated with wastewater: a systematic review and meta-analysis and probabilistic health risk assessment

The main objectives of this study were PHEs concentration meta-analysis (Fe, Zn, Cr, Ni, Cu, Pb, and Cd) in eggplant irrigated by wastewater and the following estimation of non-carcinogenic (n-CR) risk for the consumers based on countries. According to the results, the rank order of PHEs concentration in eggplant was Fe (88.3 mg/kg -dry weight) > Zn (10.1 mg/kg -dry weight) > Pb (3.0 mg/kg -dry weight) > Ni (2.7 mg/kg -dry weight) > Cu (1.1 mg/kg -dry weight) > Cd (0.9 mg/kg -dry weight) > Cr (0.05 mg/kg -dry weight). Moreover, n-CR risk showed that all investigated countries (China, India, Pakistan, Turkey, and Jordan) except for United Arab Emirates (UAE) had a considerable n-CR in both age groups (adults and children).

Characterization of the chemical composition (mineral, lead and centesimal) in pine nut (Araucaria angustifolia (Bertol.) Kuntze) using exploratory data analysis

In this study, mineral composition, centesimal composition and lead were evaluated in pine nut seeds (raw and cooked) from five Brazilian states. Mineral composition was determined by ICP OES and lead by GF AAS. The results for minerals were evaluated by Boxplot, PCA and HCA, using the R software. Average minerals in raw and cooked samples (mg 100 g^-1) were: 15.2 and 10.8 (Ca), 0.168 and 0.113 (Cu), 0.506 and 0.330 (Fe), 536 and 420 (K), 51.3 and 40.6 (Mg), 0.373 and 0.208 (Mn), 132 and 102 (P) and 0.746 and 0.520 (Zn). The average centesimal composition (raw and cooked) was: 53.5 and 47.2% (moisture), 1.76 and 1.26% (ash), 3.90 and 3.53% (protein), 40.8 and 48.0% (carbohydrate) and 179 and 206 kcal/100 g (total caloric value) and Pb was not detected. The chemometric analysis showed a distinction of raw and cooked samples due to significant nutrient losses after thermal processing.

Temporal trend of the dietary exposure to metals/metalloids: A case study in Tarragona County, Spain

In 2018, samples of various food groups were randomly purchased in different establishments of Tarragona County (Catalonia, Spain). The levels of As, Be, Cd, Cr, Hg, Mn, Ni, Pb, Sn, Tl and V were determined in the analyzed foodstuffs and their dietary intakes were estimated. Manganese was the element showing the highest concentration, while Be, Cr and Tl were not detected in any of the samples. Fish and shellfish was the only food group with detectable traces of all the remaining elements. The current levels were compared with the results of two previous surveys conducted in 1998 and 2013 in the same area. Although the levels of the analyzed elements in foodstuffs increased during the period 2013-2018, their intakes decreased by an average of 60%, due to consumption patterns changes by the population. Children and adolescents exceeded the maximum recommended intake of Ni set by the EFSA, while the dietary exposure to Pb for children was also above safety values. Compared with the concentrations found in 2013, Ni was the only element showing an increase, as well as an increase of human dietary intake. Meat, vegetables and milk were identified as the main contributors to Ni exposure. This trend was also correlated with changes in the biological burden of the same elements previously reported for the population of the area, for whom an increase of Ni in lungs was reported. Based on these results, Ni should be included as a target metal by food safety authorities, being suggested its inclusion in future Total Diet Studies.

High Concentration of Heavy Metal and Metalloid Levels in Edible Campomanesia adamantium Pulp from Anthropic Areas

This study aimed to quantify the extent of heavy metal, non-metal and metalloid levels in the Campomanesia adamantium pulp obtained from an area crossed by road experiencing high large vehicle traffic and intensive agriculture modern farming, to monitor the health risks associated with pulp consumption by humans. For this purpose, in three spots located within this area, ripe fruits were collected on the roadside, bush and farm-margin. Pulp samples were digested by microwave-assisted equipment, and chemical elements were quantified by ICP OES. The concentrations of K, Pb, Se, Fe, Mo, Zn, Co, Ni and Mn in the pulp collected in roadside/bush points showed statistical differences (p < 0.05). The heavy metals and metalloid concentrations that exceeded FAO/WHO standards were ordered Pb > As > Mo > Co > Ni > Mn > Cr. Therefore, among these metalloid and heavy metals, As, Pb and Cr were found to be higher in farm-margin > roadside > bush (1.5 × 10⁻³, 1.1 × 10⁻³ and 6.2 × 10⁻⁴), respectively. Therefore, As is the most important metalloid with higher levels in farm-margin, roadside and bush (1.5 × 10⁻³, 1.0 × 10⁻³ and 6.0 × 10⁻⁴ > 10⁻⁶–10⁻⁴ and 3.33, 2.30 and 1.34 > 1), respectively, to total cancer risk and hazard quotient, if 10 g daily of pulp are consumed.

Lead in Brazilian food: Exposure assessment and risk characterization

A risk assessment was performed to estimate the lead (Pb) dietary intake in the Brazilian population. Data on Pb concentration in food were obtained through a systematic review with meta-analyses and from the GEMS/Food database, both involving data through 2018. Food consumption data were obtained from a Brazilian official dietary survey. Pb dietary intakes were estimated by a deterministic approach. Risk characterisation was conducted using the margin of exposure approach (MOE). The total Pb intake in the Brazilian population ranged from 1.53 to 2.01 μg/kg bw/day. Major contributors to Pb dietary exposure were the vegetable and vegetable products and beverage categories. From the results obtained, a risk of increased systolic pressure, nephrotoxicity and decrease of 0.5 point intelligence quotient can be expected, MOE<1, with greater magnitudes of risk observed for men in rural areas and in the Midwest, Southeast and South Brazilian regions. The dietary risk assessment indicates a health concern for the Brazilian population associated with Pb dietary intake.

Heavy metals levels in raw cow milk and health risk assessment across the globe: A systematic review

This systematic review presents the potential toxicity of heavy metals such as lead (Pb), mercury (Hg), cadmium (Cd), iron (Fe), nickel (Ni), aluminum (Al), and copper (Cu) in raw cow milk, focusing on their contamination sources and on the assessment of the related human health risk. Multiple keywords such as "raw cow milk, heavy metals, and human health" were used to search in related databases. A total of 60 original articles published since 2010 reporting the levels of these metals in raw cow's milk across the world were reviewed. Data showed that the highest levels of Ni (833 mg/L), Pb (60 mg/L), Cu (36 mg/L) were noticed in raw cow milk collected in area consists of granites and granite gneisses in India, while the highest level of Cd (12 mg/L) was reported in barite mining area in India. Fe values in raw cow milk samples were above the WHO maximum limit (0.37 mg/L) with highest values (37.02 mg/L) recorded in India. The highest Al level was (22.50 mg/L) reported for raw cow's milk collected close to food producing plants region in Turkey. The Target Hazard Quotients (THQ) values of Hg were below 1 suggesting that milk consumers are not at a non-carcinogenic risk except in Faisalabad province (Pakistan) where THQ values = 7.7. For the other heavy metals, the THQ values were >1 for Pb (10 regions out of 70), for Cd (6 regions out of 59), for Ni (3 out of 29), and for Cu (3 out of 54). Exposure to heavy metals is positively associated with diseases developments. Moreover, data actualization and continuous monitoring are necessary and recommended to evaluate heavy metals effects in future studies.

Food-triad: An index for sustainable consumption

This study proposes an index for food labeling in order to promote sustainable consumption. The index is calculated by ranking multiple features from the environmental, health and nutritional dimensions of the target product in relation to a pre-set reference value; the obtained scores from each dimension are plotted in a radar chart resulting in a triangular area. An increase in area represents a greater impact. As examples, tuna and the potato-based foods at three different processing levels (in natura or minimally processed, processed and ultra-processed) were analyzed. For both cases, the index increases according to the processing grades and has proved to be capable of expressing in numbers and graphically a wide range of environmental, nutritional and health issues.

Development and Validation of a Spectrometric Method for Cd and Pb Determination in Zeolites and Safety Evaluation

An analytical method based on microwave-assisted acid digestion and atomic absorption spectrometry with graphite furnace as atomization source was developed and validated for determining trace elements (Cd and Pb) in zeolites used as dietary supplements, for their characterization and safety evaluation. The method was checked for the main performance parameters according to the legislation requirements in the field of dietary supplements. In all cases, the obtained performance parameters were satisfactory. The selectivity study showed no significant non-spectral matrix effect. The linearity study was conducted for the calibration curves in the range of 0–10 ng mL⁻¹ for Cd and 0–30 ng mL⁻¹ for Pb. The obtained limits of detection (LoDs) and the limits of quantification (LoQs) were sufficiently low in order to allow Pb and Cd determination in dietary supplements. For the internal quality control, certified reference materials were analysed and good recoveries were obtained. The precision study was performed in terms of repeatability and reproducibility, considering the requirements imposed by the Commission Decision (2007/333/EC) and the method fulfilled these performance parameters. Expanded measurement uncertainties were estimated to 11% for Cd and 10% for Pb. Cd and Pb content were measured in real zeolite samples and, using these data, a safety evaluation was carried out.