Change of Arsenic Speciation in Shellfish after Cooking and Gastrointestinal Digestion

α-Glucosidase Inhibitors from Cold-Pressed Black Sesame (Sesamum indicum) Meal: Characterization of New Furofuran Lignans, Kinetic Study, and In Vitro Gastrointestinal Digestion

Black sesame (Sesamum indicum) meal is an agricultural waste obtained after oil extraction. It is used as a key protein source in animal feed. Previous investigations have indicated that its health benefits, such as antidiabetic activity, are mainly due to its high lignan content. In the present study, we applied α-glucosidase inhibitory guided isolation to identify the active components responsible for the above claim. Twenty-nine compounds, mostly lignans, were isolated and identified, of which five (2-3, 12-13, and 28) were newly isolated. Of the isolated compounds, 20 and 21 were the most potent inhibitors, retarding enzyme function in noncompetitive and uncompetitive manners. Structure-activity relationship analysis suggested that the number of phenolic hydroxyl groups in the structures was significantly related to the inhibitory effect against α-glucosidase. A gastrointestinal digestion study of the major lignan sesaminol triglucoside (STG, 9) suggested that the transformation of dioxymethylene and glucoside moieties gradually began in the late process, thus enhancing the α-glucosidase inhibitory effect.

Effects of foods and food components on the in vitro bioaccessibility of total arsenic and arsenic species from Hizikia fusiforme seaweed

Seaweed is an important food source, especially in many Asian countries, because of its high nutritional value; however, increasing arsenic (As) accumulation may pose serious hazards to human health. The influence of food components on As bioaccessibility and transformation in the high As-containing seaweed Hizikia fusiforme was determined using an in vitro gastrointestinal digestion method. The results showed that co-digestion with several daily foods (such as celery, broccoli, onion, green chili, tomato) produced a higher As bioaccessibility (approximately 6-11 % increase) compared with that of seaweed alone. Vegetables such as fennel (Foeniculum valgare Mill.), celery (Apium grareolens L.), blanched garlic leaves (Allium sativum L.), scallions (Allium fistulosum L.), ginger (Zingiber officinale Rosc.), and green pepper (Capsicum frutescens L. vat. grussum Bailey) decreased bioaccessible inorganic As (18-35 %) in both the gastric and small intestinal phases. Meanwhile, the process of reducing As(V) to As(III) also occurred during co-digestion with some food matrices. Egg white and other animal proteins were the most effective reducing agents, transforming >70 % As(V) into As(III) in the solution system. These results may have important implications for health risk assessment via co-consumption. The present study provides the first evidence showing that the co-consumption of some vegetables and proteins leads to a higher toxicity of inorganic arsenic-containing food. In addition, the positive and negative effects of co-digestion on the bioaccessibility of essential metals (iron, manganese) compared to single digestion were evaluated in this study.

Transformation of arsenic species from seafood consumption during in vitro digestion

Arsenic (As) species analysis is important for the risk evaluation of seafood. Until now, there has been limited information on the change of As species during digestion. Here, the As species in different types of seafood before and after in vitro digestion were investigated. Although inorganic As was not detected in digested fish samples, As(V) contents in digested crabs and scallops were 17.12 ± 1.76 and 138.69 ± 7.53, respectively, which were approximately 2-3 times greater than those of the pre-digestion samples. In further experiments, arsenocholine, dimethylarsinate, arsenobetaine, and monomethylarsonate were all convertible to As(V) during in vitro digestions with different rates. The transformation demonstrates a complex process and could be affected by many factors, such as pH, time, and digestion juice composition, of which pH seemed to be particularly important. Free radicals were responsible for the oxidation in the transformation reactions. Unlike arsenobetaine, arsenocholine seemed to be able to directly transform to monomethylarsonate without the intermediate dimethylarsinate. This study reveals and validates the potential of other species (oAs or/and unknown species) to convert to iAs, identifies the main factors affecting this process, and proposes a reaction pathway. There is an important implication for promoting a more accurate risk assessment of arsenic in foodstuffs.

Effects of Culinary Procedures on Concentrations and Bioaccessibility of Cu, Zn, and As in Different Food Ingredients

Although cooked diets are the primary sources for humans to absorb trace elements, there is limited data available on the concentrations and bioaccessibility of trace elements in cooked food ingredients. This work aims to evaluate the effects of culinary procedures on the concentrations and bioaccessibility of trace elements in common food ingredients. Twelve food species from the local market were treated with four culinary procedures (boiling, steaming, baking, and frying), then the bioaccessibility of copper (Cu), zinc (Zn), and arsenic (As) were evaluated using the in vitro digestion method. The subcellular distribution of these elements was also determined using the sequential fractionation method. The results show that culinary procedures decreased the retention rate of As during cooking (100% for raw and 65-89% for cooked ingredients) and the bioaccessibility of Cu and Zn during digestion (nearly 75% for raw and 49-65% for cooked ingredients), resulting in a reduction of the total bioaccessible fraction (TBF) of Cu, Zn, and As in food ingredients. The TBF of Cu, Zn, and As in all tested food ingredients followed the order: raw (76-80%) > steaming and baking (50-62%) > boiling and frying (41-50%). The effects of culinary procedures were associated with the subcellular distribution of trace elements. As was dominantly distributed in heat-stable proteins (51-71%), which were more likely to be lost during cooking. In comparison, Cu and Zn were mainly bound to the insoluble fraction and heat-denatured proteins (60-89% and 61-94% for Cu and Zn, respectively), which become less digestible in cooked ingredients. In conclusion, these results suggest that culinary procedures reduce the absorption of Cu, Zn, and As in various food ingredients, which should be considered in the coming studies related to nutrition and risk assessment of trace elements.

Chronic dietary exposure to total arsenic, inorganic arsenic and water-soluble organic arsenic species based on results of the first German total diet study

For risk assessment purposes, the dietary exposure to total arsenic and inorganic arsenic was estimated within the first German total diet study (BfR MEAL Study) for the whole population in Germany. Therefore, occurrence data of 356 different foods from the BfR MEAL Study were combined with consumption data from German nutrition surveys. Due to the different toxicological potentials of other water-soluble organic arsenic species present in rice-based foods, fish and seafood, dietary exposure to dimethylarsinic acid, monomethylarsonic acid and arsenobetaine was assessed in consumers in Germany through such foods for the first time. Related to the bodyweight, dietary exposure to total arsenic and inorganic arsenic in infants and young children (0.5-<5 years) were higher than in adolescents/adults (≥14 years). The highest median exposure estimates to inorganic arsenic resulted for the age group of infants from 0.5 to <1 year under modified lower bound conditions and for young children from 1 to <2 years under upper bound conditions (0.17 μg kg^-1 bodyweight day^-1-0.24 μg kg^-1 bodyweight day^-1 and 0.26 μg kg^-1 bodyweight day^-1-0.34 μg kg^-1 bodyweight day^-1, respectively). 'Grains and grain-based products' (especially rice) were identified as the main contributors for dietary exposure to total arsenic and inorganic arsenic for all age classes. Especially, for infants and young children, high consumption of rice-based foods and fish fingers is driving the dietary exposure to dimethylarsinic acid. The dietary exposure calculations indicate that a further reduction of dietary exposure to inorganic arsenic and further investigations to water-soluble organic arsenic species are necessary.

Changes in Arsenic Speciation in Wild Edible Fungi after Different Cooking Processes and Gastrointestinal Digestion

Arsenic (As) is enriched in wild edible fungi, which is one of the main important sources of As in humans' diet. In this study, two wild edible fungi were employed for investigation: (1) Pleurotus citrinopileatusone, which contains a high content of inorganic As (iAs) and (2) Agaricus blazei Murill, which contains a high content of organic As. This study investigated the changes in As content and its speciation after different daily cooking methods. We found that the content of As in Pleurotus citrinipileatus and Agaricus blazei Murill reduced by soaking plus stir-frying by 55.4% and 72.9%, respectively. The As content in Pleurotus citrinipileatus and Agaricus blazei Murill decreased by 79.4% and 93.4%, respectively, after soaking plus boiling. The content of As speciation in dried wild edible fungi reduced significantly after different treatments. Among them, iAs decreased by 31.9~88.3%, and organic As decreased by 33.3~95.3%. This study also investigated the bioaccessibility of As in edible fungi after different cooking processes via an in-vitro physiologically based extraction test (PBET). The results showed that the bioaccessibility of As was relatively high if the edible fungi were uncooked, boiled, or stir-fried. The gastric (G) bioaccessibility of As ranged from 51.7% to 93.0% and the gastrointestinal (GI) bioaccessibility of As ranged from 63.5% to 98.1%. Meanwhile, the bioaccessibility of inorganic As was found to be as high as 94.6% to 151%, which indicates that further evaluation of the potential health risks of wild edible fungi is necessary.

Dietary exposure to heavy metals and iodine intake via consumption of seaweeds and halophytes in the European population

EFSA assessed the relevance of seaweed and halophyte consumption to the dietary exposure to heavy metals (arsenic, cadmium, lead and mercury) and the iodine intake in the European population. Based on sampling years 2011-2021, there were 2,093 analytical data available on cadmium, 1,988 on lead, 1,934 on total arsenic, 920 on inorganic arsenic (iAs), 1,499 on total mercury and 1,002 on iodine. A total of 697 eating occasions on halophytes, seaweeds and seaweed-related products were identified in the EFSA Comprehensive European Food Consumption Database (468 subjects, 19 European countries). From seaweed consumption, exposure estimates for cadmium in adult 'consumers only' are within the range of previous exposure estimates considering the whole diet, while for iAs and lead the exposure estimates represent between 10% and 30% of previous exposures from the whole diet for the adult population. Seaweeds were also identified as important sources of total arsenic that mainly refers, with some exceptions, to organic arsenic. As regards iodine, from seaweed consumption, mean intakes above 20 μg/kg body weight per day were identified among 'consumers only' of Kombu and Laver algae. The impact of a future increase in seaweed consumption ('per capita') on the dietary exposure to heavy metals and on iodine intake will strongly depend on the seaweeds consumed. The exposure estimates of heavy metals and iodine intakes in 'consumers only' of seaweeds were similar to those estimated in a replacement scenario with selected seaweed-based foods in the whole population. These results underline the relevance of the current consumption of seaweeds in the overall exposure to different heavy metals and in the intake of iodine. Recommendations are provided for further work needed on different areas to better understand the relationship between seaweed consumption and exposure to heavy metals and iodine intake.

Determination of arsenic in Chinese mitten crabs (Eriocheir sinensis): Effects of cooking and gastrointestinal digestion on food safety

This study used the sexually mature Chinese mitten crabs as the research object, and the total arsenic and six major species were determined by high-performance liquid chromatography-inductively coupled plasma mass spectrometry (HPLC-ICP-MS). The influence of three common cooking methods on the forms of arsenic and content in different edible parts of crabs were explored. Furthermore, the bioavailability of arsenic and its different forms in the crabs were studied by in vitro gastrointestinal digestion. Based on the risk assessment of arsenic in gastrointestinal digestion, the results showed that the Target Hazard Quotient (THQ) of arsenic was less than 1, which did not pose a significant health risk, but the risk of carcinogenesis of arsenic can not be ignored. Considering the effects of cooking and gastrointestinal digestion into account, a more realistic estimate of the risk associated with the consumption of Chinese mitten crabs can be deciphered.

Chemical Content of Five Molluscan Bivalve Species Collected from South Korea: Multivariate Study and Safety Evaluation

Bivalves are a good source of nutrients but also a potential source of environmental contaminants, which could pose a risk for consumers. The aims of this study were: the determination of 16 elements by ICP-MS in 48 samples of five bivalve species purchased from market in Korea; the identification of elements useful for species classification using multivariate analyses; and the benefit-risk evaluation associated to the consumption of these bivalves. The highest difference among content of elements between species was found for Cd, Mn, Ni, Zn, and Fe. Partial last squares discriminant analysis revealed elements with a VIP score >1 which were considered as the most relevant for explaining certain species. As, Cd, Co, and Ni were found as taxonomical markers of V. philippinarum; Mn, Zn, Mg, and Na of A. irradians; and Cd, Ni, and Fe of M. yessoensis. These species could serve as good dietary sources of essential elements. Cd exposure by consumption of Manila clams is not representing a health risk for the Korean population; however, through consumption of Yesso scallops, 5.3% of the Korean population has a potential health risk. Removal of the digestive gland before eating will drastically reduce the amount of Cd ingested.

Bioaccessibility and bioavailability adjusted dietary exposure of cadmium for local residents from a high-level environmental cadmium region

The critical health risks caused by cadmium (Cd) via dietary exposure are commonly assessed by detecting Cd concentrations in foods. Differently, in this study, the bioaccessibility and bioavailability of Cd in major local harvests were introduced to assess the dietary exposure of local residents from a high-level environmental Cd region. The results indicated that certain Cd was released into the digestive juice after in vitro digestion with a bioaccessibility of 20-63% for rice and 3-32% for leafy vegetables, and the released portion was partially absorbed by Caco-2 cells with a bioavailability of 2-21% for rice and 0.2-13% for leafy vegetables. The results obtained from the toxicokinetic model revealed that the predicted urinary Cd values from the estimated daily intake (EDI) of Cd, which accounted for bioaccessibility and bioavailability, were consistent with the actual measured values, and the EDIs were considerably lower than the acceptable daily intake. This suggests that the bioaccessibility and bioavailability adjusted dietary Cd exposure should be more precise. The key issues addressed in our study implores that a potential health risk cannot be neglected in people with high consumption of rice from high-level zone.

Arsenic speciation and bioaccessibility in raw and cooked seafood: Influence of seafood species and gut microbiota

Seafood is an important source of arsenic (As) exposure for humans. In this study, 34 seafood samples (fishes, shellfishes, and seaweeds) collected from different markets in China were analysed for total and speciated As before and after boiling. Furthermore, the As bioaccessibility was also assessed using a physiologically based extraction test combined with the Simulator of Human Intestinal Microbial Ecosystems. The results showed that the total As (tAs) contents of seaweeds (raw: 44.12; boiled: 31.13, μg·g^-1 dw) were higher than those of shellfishes (raw: 8.34; boiled: 5.14, μg·g^-1 dw) and fishes (raw: 6.01; boiled: 3.25, μg·g^-1 dw). Boiling significantly decreased the As content by 22.24% for seaweeds, 32.27% for shellfishes, and 41.42% in fishes, respectively (p < 0.05). During in vitro digestion, the bioaccessibility of tAs and arsenobetaine (AsB) significantly varied between the investigated species of seafood samples in gastric (G) and small intestinal phases (I) (p < 0.05). Higher tAs bioaccessibility (G: 68.6%, I: 81.9%) were obtained in fishes than shellfishes (G: 40.9%, I: 52.5%) and seaweeds (G: 31%, I: 53.6%). However, there was no significant differences in colonic phase (C) (p > 0.05). With the effect of gut microbiota, arsenate (As^Ⅴ) was transformed into monomethylarsonic acid (MMA) and arsenite (As^Ⅲ) in C. Moreover, as for seaweeds, an unknown As compound was produced.

Total arsenic and water-soluble arsenic species in foods of the first German total diet study (BfR MEAL Study)

Arsenic can occur in foods as inorganic and organic forms. Inorganic arsenic is more toxic than most water-soluble organic arsenic compounds such as arsenobetaine, which is presumed to be harmless for humans. Within the first German total diet study, total arsenic, inorganic arsenic, arsenobetaine, dimethylarsinic acid and monomethylarsonic acid were analyzed in various foods. Highest levels of total arsenic were found in fish, fish products and seafood (mean: 1.43 mg kg-1; n = 39; min-max: 0.01-6.15 mg kg-1), with arsenobetaine confirmed as the predominant arsenic species (1.233 mg kg-1; n = 39; min-max: 0.01-6.23 mg kg-1). In contrast, inorganic arsenic was determined as prevalent arsenic species in terrestrial foods (0.02 mg kg-1; n = 38; min-max: 0-0.11 mg kg-1). However, the toxicity of arsenic species varies and measurements are necessary to gain information about the composition and changes of arsenic species in foods due to household processing of foods.

A survey of arsenic, mercury, cadmium, and lead residues in seafood (fish, crustaceans, and cephalopods) from the south-eastern Mediterranean Sea

Seafood is capable of bioaccumulating heavy metals (HM), making it a potentially major dietary source of HM for humans. Presently, little data exists on seafood from the eastern-most boundary of the Mediterranean Sea. This study aims to provide exposure insight of the Israeli population to HM through the consumption of locally caught seafood by assessing the levels of arsenic, mercury, cadmium, and lead in raw tissues of seafood. A wide survey of local fisheries was conducted providing 296 samples from 11 different species, including seven fish, two crustacean, and two cephalopod species. Total arsenic, cadmium, and lead were analyzed by graphite-furnace atomic absorption. Total mercury was measured by cold-vapor mercury analyzer. Arsenic speciation was performed by anion chromatography-inductively coupled plasma sector field mass spectrometry. Results suggested that the total arsenic concentrations were significantly higher in crustaceans and cephalopods than fish. Arsenic speciation revealed two samples that exceed 1 mg/kg of inorganic arsenic, whereas methylated arsenic was below the detection limit. Elevated mercury levels were detected in the commercial benthic species Mullus barbatus (red mullet), cadmium was detected in one-third of the samples, and lead detected in eight samples. Comparing the results to health guidelines, 99.4% of seafood tested in this study abide with acceptable levels of heavy metals in seafood, as defined by both Israeli and European Union guidelines.

Processing Aids in Food and Beverage Manufacturing: Potential Source of Elemental and Trace Metal Contaminants

There are currently increased efforts to determine potential sources of trace metal contaminants in the food supply. While there are likely many sources of these elements, processing of foods has gained attention as one such route. Research is reviewed on how processing aids used for food production, including beverage filtration and fining, have been targeted as potential sources of trace metals. Potential remediation methods to reduce elemental transfer occurring during processing is discussed. While food processing aids are often a critical part of food manufacturing, they can be a potential source of trace metal contaminants, including heavy metals.

Multiple metal(loid)s bioaccessibility from cooked seafood and health risk assessment

Seafood has been generally considered to be the main diet exposure source of metal(loid)s. We evaluated health risk of mercury (Hg), arsenic (As), cadmium (Cd), lead (Pb), chromium (Cr), nickel (Ni), copper (Cu), and zinc (Zn) through consumption of cooked seafood based on bioaccessibility, which was obtained by physiologically based extraction test method. Results showed that cooking practices could decrease metal(loid)s concentration from seafood (by 6.0-45.7%). Metal(loid)s release from seafood in this study followed the descending order of Hg > Zn > Ni > Cd > Pb > As > Cu > Cr. On average, cooking lowered the bioaccessibility of As, Hg, Cd, Pb, Ni, Cr, Cu, and Zn by 15.2, 26.1, 30.9, 30.7, 25.7, 31.2, 17.6, and 22.4%, respectively. Health risk calculation results showed that Cr, Ni, and Zn in seafood species in this study were within the human health benefits range. Hg, Cd, Pb, and Cu exposure from cooked seafood was within the safe dose. However, we found that there is a potential of having cancer (especially bladder and lung cancer) for people exposure to iAs from seafood based on bioaccessible contents the first time.

Bioaccessibility of arsenic from gastropod along the Xiangjiang River: Assessing human health risks using an in vitro digestion model

The bioaccessibility of total arsenic (tAs) and arsenic species in Bellamya aeruginosa collected from Xiangjiang River was evaluated using an in vitro digestion model, to assess the potential health risks to local residents. The tAs concentrations in gastropod samples ranged from 1.98 to 6.33 mg kg^-1 (mean 3.79 ± 1.60 mg kg^-1). Five arsenic species including arsenite [As(III)], arsenate [As(V)], dimethylarsinic acid (DMA), arsenobetaine (AsB), and arsenocholine (AsC) were detected. Inorganic arsenic (iAs) concentrations, which were about a half of organic arsenic (oAs), were higher than the maximum permissible limit (≤0.50 mg kg^-1 in aquatic products). Bioaccessible concentrations of tAs in digestive juices were found to be decreased in the order: intestinal phase > gastric phase > salivary phase. As(III) and AsC were the predominant species, but AsB was not detectable in all digestive juices. Bioaccessible iAs concentrations, which were close to the level of bioaccessible oAs, were not significantly different among three digestive juices, but also above 0.50 mg kg^-1. Accordingly, bioaccessibility of tAs was highest in intestinal phase (48%), then in gastric phase (40%), and lowest in salivary phase (33%). Bioaccessibility of As(III) was close to 100%, and bioaccessibility of iAs was much higher than that of oAs. The mean values of target hazard quotient (THQ) and bioaccessible THQ were 0.80 and 0.70, respectively. The probability of experiencing non-carcinogenic effects was reduced to 18% down from 22% as considering iAs bioaccessibility. The mean values of carcinogenic risk (CR) and bioaccessible CR were higher than the acceptable value (1 × 10^-4). Gastropod consumption from sampling sites may cause a potential carcinogenic risk.

Evaluation of the influence of different cooking pot types on the metallic elements content in edible chicken tissues by MIP OES

Abstract This work describes the analysis of different chicken tissues (gizzard, heart, and liver) both raw and cooked with seasonings in different types of cooking pots (iron pot, , aluminum pot and hammered aluminum pot) commonly used in Brazil. The samples were decomposed using microwave-assisted digestion with diluted nitric acid; and the contents of Al, Ca, Cu, Fe, Mn and Ni were determined using Microwave Induced Plasma Optical Emission Spectrometry (MIP OES). The Fe content was also determined by Flame Atomic Absorption Spectrometry, and the comparison showed good accuracy of the method. The limits of quantification were below 0.011 mg kg-1, showing adequate detectability. Cooking in the different pots increased the ash and protein contents as well as decreased the moisture content. Box-plot and Principal Components Analysis showed that Ca and Fe contents present the largest variations in the samples, followed by Al and moisture. The variables Al, Cu, Mn, Ni, ash, and protein presented similar behavior after cooking in all different pots. In addition, liver cooked in both iron and hammered aluminum pots presented similar Fe contents, while gizzard and heart showed similar Ca contents.

Polybrominated diphenyl ethers in the environment and human external and internal exposure in China: A review

Polybrominated diphenyl ethers (PBDEs) are widely used as brominated flame retardants. Because of their toxicity and persistence, some PBDEs were restricted under the Stockholm Convention in 2009. Since then, many studies have been carried out on PBDEs in China and in many other countries. In the present review, the occurrences and contamination of PBDEs in air, water, sediment, soil, biota and daily food, human blood, hair, and other human tissues in China are comprehensively reviewed and described. The human exposure pathways and associated health risks of PBDEs are summarized. The data showed no obvious differences between North and South China, but concentrations from West China were generally lower than in East China, which can be mainly attributed to the production and widespread use of PBDEs in eastern regions. High levels of PBDEs were generally observed in the PBDE production facilities (e.g., Jiangsu Province and Shandong Province, East China) and e-waste recycling sites (Taizhou City, Zhejiang Province, East China, and Guiyu City and Qingyuan City, both located in Guangdong Province, South China) and large cities, whereas low levels were detected in rural and less-developed areas, especially in remote regions such as the Tibetan Plateau. Deca-BDE is generally the major congener. Existing problems for PBDE investigations in China are revealed, and further studies are also discussed and anticipated. In particular, non-invasive matrices such as hair should be more thoroughly studied; more accurate estimations of human exposure and health risks should be performed, such as adding bioaccessibility or bioavailability to human exposure assessments; and the degradation products and metabolites of PBDEs in human bodies should receive more attention. More investigations should be carried out to evaluate the quantitative relationships between internal and external exposure so as to provide a scientific basis for ensuring human health.

Change in mercury speciation in seafood after cooking and gastrointestinal digestion

Mercury (Hg) is readily bioaccumulated in seafood, a common ingredient in indigenous cuisines throughout the world. This study investigates Hg speciation in cooked seafood after gastric and intestinal digestion. The results showed that the removal of Hg by washing was negligible. Additionally, the results of our calculations regarding the mass balance of Hg concentration indicated that cooking reduced Hg mainly by means of volatilization and that Hg²⁺ was more readily reduced than MeHg. Moreover, cooking lowered the bioaccessibility of Hg in seafood: the reduced percent of bioaccessible Hg²⁺ after cooking ranged from 2 to 35% (on average, 16%). The corresponding numbers were slightly lower compared with those for MeHg (on average, 19%). Furthermore, there might be a chemical transformation of Hg during in vitro gastrointestinal digestion. The results of in vivo tests in laboratory mice suggested that methylation of Hg mainly took place in the gastric tract, whereas demethylation of Hg occurred primarily during intestinal digestion. These findings indicate that the bioaccessibility of Hg²⁺ and MeHg was not only related to their initial concentrations in the food samples, but also that further studies on the mechanisms of Hg demethylation and methylation during gastrointestinal digestion are essential for more realistic risk assessments.

Factors Affecting Transfer of the Heavy Metals Arsenic, Lead, and Cadmium from Diatomaceous-Earth Filter Aids to Alcoholic Beverages during Laboratory-Scale Filtration

Filtration methods for alcoholic fermented beverages often use filter aids such as diatomaceous earth (DE), which may contain elevated amounts of the heavy metals arsenic (As), lead (Pb), and cadmium (Cd). Here, we evaluated factors affecting transfer of these heavy metals from DE to beer and wine. A laboratory-scale filtration system was used to process unfiltered ale, lager, red wine, and white wine with three types of food-grade DE. Filtrate and DE were analyzed for heavy metals using ICP-MS, in addition to LC-ICP-MS for As-speciation analysis. Use of 2 g/L DE containing 5.4 mg/kg soluble inorganic As (iAs) for filtering beer and wine resulted in significant ( p < 0.05) increases of 11.2-13.7 μg/L iAs in the filtered beverage. There was a significant ( p < 0.05) effect from the DE quantity used in filtration on the transfer of iAs in all beverage types, whereas no alterations were observed for Pb and Cd levels. Methods to wash DE using water, citric acid, or EDTA all significantly ( p < 0.05) reduced iAs concentrations, whereas only EDTA significantly reduced Pb levels. Cd concentrations were not affected by any wash method. These data indicate that specific steps can be taken to limit heavy-metal transfer from DE filter aids to beer and wine.