Monitoring of metal and metalloid content in dietary supplements on the Croatian market

Mercury Levels in Selected Medicines and Dietary Supplements in Poland

Current trends are promoting youth, beauty, health, and fitness. Individuals often seek out remedies, such as medicines or dietary supplements (DS), to achieve these goals. However, highly processed foods, chronic stress, and environmental pollution contribute to the development of civilization diseases. The aim of this study was to evaluate the mercury (Hg) content in medicines and DS that are available in Poland. A total of 139 preparations were tested (75 drugs, 64 DS). The medicines contained preparations belonging to antibacterial, antiviral, antifungal; analgesic, antipyretic, and anti-inflammatory; heart and blood vessel disease preventatives; respiratory tract infections treatment; diuretics; aiding digestion; supplements; antidiarrhoeals; anti-allergics; anti-rheumatics; antibiotics; and others. The tested dietary supplements had an effect on the following: improve the condition of skin, hair, and nails; vitamins; minerals; probiotics; weight loss; special for women; and others. The Hg content of the samples was determined using atomic absorption spectrometry (AAS). The Hg content of all the preparations varied widely (0.1-57.4 µg/kg), with a median Hg concentration of 1.2 µg/kg. The median Hg concentration for medicines was 0.8 µg/kg, prescription medicines having higher Hg concentrations (0.9 µg/kg) than over-the-counter (OTC) drugs (0.5 µg/kg). For DS, the Hg content was found to be higher than for drugs, at 2.0 µg/kg. The herbal preparations showed the highest Hg content among the individual DS groups (3.4 µg/kg). The Hg concentrations in the tested drug and DS samples did not exceed acceptable standards. However, if multiple pharmaceutical preparations are taken simultaneously over a long period of time, and there is existing environmental exposure, there is a possibility of Hg concentration accumulation and adverse health effects.

Multi-elemental composition of botanical preparations and probabilistic evaluation of toxic metals and metalloids intake upon dietary exposure

The aim of this study was to evaluate the inorganic elemental composition (49 elements) of 29 botanical preparations obtained from fruits, leaves, peels, seeds, roots, fungi, and spirulina by using inductively coupled-mass spectrometry and a mercury analyzer. Simultaneously, the risk associated with the chronic dietary exposure to 12 toxic metals and metalloids among the European population was evaluated by using a probabilistic approach based on Monte Carlo simulations. The analysis revealed worrying intake levels of Al, As, and Ni, primarily stemming from the consumption of spirulina-, peel-, and leaf-based botanicals by younger age groups. The intake of As from all analyzed botanicals posed a significant risk for infants, yielding margins of exposure (MOEs) below 1, while those deriving from peel-based botanicals raised concerns across all age groups (MOEs = 0.04-2.3). The consumption of peel-based botanicals contributed substantially (13-130%) also to the tolerable daily intake of Ni for infants, toddlers, and children, while that of spirulina-based botanicals raised concerns related to Al intake also among adults, contributing to 11-176% of the tolerable weekly intake of this element. The findings achieved underscore the importance of implementing a monitoring framework to address chemical contamination of botanicals, thus ensuring their safety for regular consumers.

Toxic elements in children's multivitamin-multimineral supplements and the health risks they pose

This work aimed to determine the levels of toxic elements (As, Cd, Hg, and Pb) and their risks in children's multivitamin-multimineral (CMVM) supplements. An inductively coupled plasma-mass spectrometer (ICP-MS) was used to quantify the studied elements. The mean concentrations and ranges (μg/kg) of the toxic elements in the CMVM products were as follows: As (32.4, 5.3-90); Cd (58.2, 6-129); Hg (42.2, 6-108); and Pb (231,8.6-541). The estimated oral daily intakes (EODI) were determined to be in the range of 0.01-0.31 g/day, 0.01-0.64 g/day, 0.02-0.53 g/day, and 0.01-2.36 g/day for As, Cd, Hg, and Pb, respectively. All the EODI values were below the tolerable intake limits set for each element. The chronic non-cancer risks associated with oral exposure to studied elements were evaluated using the target hazard quotient (THQ) and the hazard index (HI). The THQ and HI values were below 1, indicating that these products were safe for consumption by children. The potential cancer risks associated with exposure to As and Pb through the consumption of CMVM products were determined using the Incremental Lifetime Cancer Risk (ILCR) and the total cancer risks (TCR). The ILCR and TCR values were below the threshold value of 1 × 10-4, indicating that the risk of developing cancer was very low and ignorable.

Assessment of the Mineral Composition and the Selected Physicochemical Parameters of Dietary Supplements Containing Green Tea Extracts

Our aim was to assess the mineral composition as well as the physicochemical quality of green tea-based dietary supplements (capsules and tablets) with respect to average weight, size and shape, friability, breaking force and disintegration time. Products were analysed by flame atomic absorption spectrometry for Ca, K, Mg, Na, Cr, Cu, Fe, Zn, Mn, Pb and Cd. Approximately 60% of the analysed supplements met the requirements of European and Polish regulations. The dietary supplements passed weight variation tests, but not all products had compliant capsule sizes. One product in tablet form failed the friability test, and eleven dietary supplements in tablet form failed the disintegration test. The supplements were characterised by a varied elemental composition, with the highest values found for Ca, Fe, Zn and Mn. The recommended daily allowance realisation for Fe and Zn in two dietary supplements (capsule form) exceeded 100%. As a result of the estimation of the monthly intake of toxic metals, it was concluded that the tested products do not pose a risk to consumer health. Significant relationships (p < 0.001) were found for K, Mg, Na, Cu, Fe, Mn and Zn. The application of factor and cluster analyses allowed the verification of the similarity of green tea extracts contained in dietary supplements to the natural raw material, green tea leaves, used as a reference material.

Application of Liquid Chromatography Coupled to Mass Spectrometry in Quality Assessment of Dietary Supplements—A Case Study of Tryptophan Supplements: Release Assay, Targeted and Untargeted Studies

Dietary supplements are widely consumed in the EU and the USA. Based on their similarity to pharmaceuticals, consumers mistakenly believe that dietary supplements have also been approved for safety and efficacy. However, in the absence of mandatory testing, data on supplement quality is scarce. Thus, we applied liquid chromatography coupled with tandem mass spectrometry to analyse the quality of dietary supplements containing tryptophan (Trp). We examined 22 supplements in tablets or capsules, produced in the USA, Great Britain, Germany, France, Czech Republic, and Poland. Trp release, crucial for bioavailability and efficiency, was assessed. Additionally, we performed a qualitative analysis of the main ingredient and screened for contaminants. Among the contaminants, we detected Trp’s metabolites, condensation products of Trp and carbonyl compounds, Trp degradation products, degradation products of kynurenine, and other contaminants such as glucosamine and melatonin. The main ingredient content was in the range of 55–100% in capsules and 69–87% in tablets. Surprisingly, almost no Trp release was noted from some supplements. Our study confirms the need to advance research on supplements. We believe that the high-quality analysis of supplements based on reliable analytical techniques will be an important contribution to the discussion on the regulatory framework of these products.

Quality Control of Protein Supplements: A Review

The growing consumer awareness regarding health and fitness has been leading to a huge rise in the consumption of nutritional supplements and, consequently, to an increase in concerns about their quality. In this sense, one of the most consumed products is protein supplements and, despite being safer than other types of supplements, there are several studies showing incompatibilities between what is present on the labels and their actual content. Therefore, this review is focused on gathering information about the problems arising from poor manufacturing practices and inadequate quality control of sport protein supplements. These issues are mainly related to three aspects: reduction of the supplements’ nutritional value, the presence of pharmacological substances, and contamination with microorganisms or toxic metals. Regarding the first aspect, reports about the “classic” addition of nitrogen-rich compounds to mask the protein content measured by the Kjeldahl method were discussed, as well as recent topics such as the addition of cheaper proteins to produce an “undetectable” adulteration in whey protein supplements. With respect to the presence of pharmacological compounds, it is a finding that is not very common in protein supplements; however, even trace amounts of foreign substances in this type of product may cause adverse effects to consumers, and, in the case of an elite athlete, may result in doping. Finally, we discuss about the contamination with microorganisms and toxic metals, this latter being a subject that should be further explored due to few studies in the literature.

Food Supplements for Weight Loss: Risk Assessment of Selected Impurities

Nowadays, food supplements are widely consumed, often without any medical supervision. In this study, 25 food supplements for weight loss, randomly purchased from five different suppliers in the European Union, were analysed by Wavelength Dispersive X ray Fluorescence spectrometry (WDXRF). The aim of this study was the risk assessment of trace elements and the mixture of elements present in food supplements for weight loss. The obtained Hazard Index (0.11) showed no potential risk of non-carcinogenic effects to human health. However, since humans are frequently exposed by different routes and/or sources to toxic metals, the additional consumption of these products may cause potential toxicological risks that cannot be ignored. In one analysed food supplement (FS), the simultaneous presence of Pb and Mn in high concentrations was detected. In two, FS chromium concentrations were above the reference daily dose. Unconformities were detected between the labelled and the detected values, which emphasises the misinformation of labels. This highlights the need for a deeper surveillance of food supplements.

Contaminants: a dark side of food supplements?

Food supplements (FS) are often consumed as one of the strategies to fight ageing-associated pathologies, especially in the case of oxidative stress-related diseases. Despite the popularity of FS, some concerns about their quality and safety have been raised, especially regarding the presence of contaminants. This paper reviews and discusses the occurrence of contaminants in marketed samples of FS in the last two decades, considering both scientific literature and notifications registered on RASFF portal. The most relevant classes of contaminants were included namely metals, toxins, pesticides, dioxins and PCBs, as well as pharmacologically active ingredients. Variable amounts of contaminants were reported in a significant number of commercially available FS. Although the presence of contaminants does not necessarily mean that their levels exceed the regulatory limits or that the FS intake constitutes a risk to human health, it alerts for the need to further monitor FS safety. The evaluation of the risk associated to the consumption of FS, especially in the elderly population, is particularly challenging due to the frequent exposure to multiple toxicants and to different exposure sources, as well as due to possible pre-existing diseases and respective therapeutics. Therefore, improved quality control procedures and monitoring programs should be pursued in order to avoid undesirable products and assure the safety of FS.

Lead and cadmium in foods/drinking water from Slovenian market/taps: Estimation of overall chronic dietary exposure and health risks

Approximately 3000 food samples from the Slovenian market and 2500 drinking (tap) water samples in the period 2011 - 2016 were evaluated for the presence of toxic elements lead (Pb) and cadmium (Cd) and the overall chronic dietary exposure was assessed for each element. The highest mean concentrations were found for Pb in products for special nutritional use - dietary supplements (0.383 mg/kg) and for Cd in fish and seafood (0.117 mg/kg). The consumption data were obtained from the national study of the household budget and from the European Food Safety Authority (EFSA) summary statistics. Chronic dietary exposure was estimated deterministically. The average Pb and Cd intakes from food and drinking (tap) water ranged for children from 0.90 to 1.021 µg/kg bw/day and 4.65 to 5.65 µg/kg bw/week, respectively, and for adults, including adolescents, from 0.40 to 0.53 µg/kg bw/day and 1.98 to 2.82 µg/kg bw/week, respectively. The high consumption of cereal-based foods and vegetables contributed most to overall Pb and Cd intake in the majority of the age groups. The exposure to Pb was generally lower and that to Cd was higher compared to the average EU values. The most exposed were children, as the health-based guidance values were exceeded for both elements, which indicates a health concern. An important contribution to Cd exposure can be attributed to grains and potatoes grown in Slovenia, where the soil contains more Cd than that in other EU countries. Further efforts to reduce Pb and Cd intake are required to minimize potential health risks.

The Content of Mercury in Herbal Dietary Supplements

The dietary supplement market in Poland has been growing rapidly, and the number of registered products and their consumption increases steadily. Among the most popular and the easiest to get are herbal supplements, available in any supermarket. The aim of this paper was to investigate the mercury content in the herbal supplements. The dietary supplements that have been examined (24) are available on the Polish market and contain one or more herbal ingredients. Supplements were pulverized in porcelain mortar and identified by AMA 254 atomic absorption spectrometer. The range of variations for all tested supplements was within 0.02-4293.07 μg/kg. The arithmetic mean of the total result was 193.77 μg/kg. A higher mercury content then this mean was found in preparations-bamboo shoots and alga Chlorella pyrenoidosa. The studies have shown that mercury is present in every examined herbal supplement, and its content exceeds in two preparations (with bamboo and alga) the permissible limit of 0.10 mg/kg. There were statistically significant differences in the occurrence of mercury depending on the herbal ingredient in the supplement. The lowest content was found in the preparation with Tanacetum parthenium and the highest with bamboo shoots. The mercury content in the tested herbal supplements was statistically significant in the form of a supplement-a tablet and a capsule. Daily, weekly, monthly, and yearly consumption of mercury with examined supplements was calculated-the results did not exceed the PTWI-provisional tolerable weekly intake of mercury. To increase consumer safety, it is imperative to conduct further research on dietary supplements and implement a stricter quality control of the dietary supplements.

Is there a risk of trace element contamination in herbal preparations? A test study on the lichen Cetraria islandica

Lichens are a source of unique secondary metabolites, which have been proved to have many biological properties with possible pharmaceutical roles, including e.g. antioxidant, antimicrobial, antifungal or anti-inflammatory activities and to be worth of consideration for potential human use. However, lichens lack cuticolar tissues and are exposed to several atmospheric contaminants, including trace elements. This work aims at exploring the potential toxicity of herbal preparations derived by the lichen Cetraria islandica due to trace element contamination, testing whether different concentrations may be observed, depending on the origin of the raw material. Fourteen samples of C. islandica, as cut dried thalli occurring on the European market, have been bought from different providers. For each sample, the concentrations of As, Cd, Co, Cu, Fe, Mn, Ni, P, Pb, V and Zn were measured on comminuted herbal substance and on the corresponding decoction, using atomic emission spectrometry (ICP-OES). The elemental concentrations in decoctions were significantly lower than those measured in raw materials, dropping down to levels of negligible health concern. Differences observed in raw materials were not observed anymore in the corresponding decoctions. Also, the elemental transfer rate from dried lichen to decoction was extremely element-specific, ranging from 2% for Cu to 95% for Zn.

Method development for the determination of elements in Hypericum perforatum L. (St John's wort) herb and preparations using inductively coupled plasma–optical emission spectroscopy and microwave digestion

Objectives

A method was developed to analyze St John's wort (Hypericum perforatum L.) herb and preparations using inductively coupled plasma–optical emission spectroscopy (ICP-OES) to determine the quantity of 11 elements (Al, B, Ba, Ca, Cu, Fe, Mg, Mn, Ni, Sr and Zn).

Methods

This study includes the evaluation of digestion acids and calibration methods, as well as instrumental parameters such as choice of nebulizer and emission wavelength.

Key findings

Two nebulizers (Conikal and SeaSpray) performed similarly for most elements, and two optimum wavelengths were determined for each element. Five acids were evaluated for the digestion of the Polish Certified Reference Material Tea Leaves (INCT-TL-1), while three were taken forward to use for the different St John's wort formulations (i.e. herb, capsule and tablet). A simple protocol using 5 ml HNO3 was sufficient in most cases; however, variability was observed for elements often bound in silicates (e.g. Al, Fe and Zn). An external weighted calibration was also found to be preferential over unweighted, and the use of standard addition affected some concentration values up to 20%.

Conclusions

Therefore, this paper presents the development and optimized method parameters to be used with ICP-OES that will allow the analysis of 11 key elements present in St John's wort herb and preparations.

Evaluation of heavy metals content in dietary supplements in Lebanon

BACKGROUND

The consumption of dietary supplements is widely spread and on the rise. These dietary supplements are generally used without prescriptions, proper counseling or any awareness of their health risk. The current study aimed at analyzing the metals in 33 samples of imported dietary supplements highly consumed by the Lebanese population, using 3 different techniques, to ensure the safety and increase the awareness of the citizen to benefit from these dietary supplements.

RESULTS

Some samples had levels of metals above their maximum allowable levels (Fe: 24%, Zn: 33%, Mn: 27%, Se: 15%, Mo: 12% of samples), but did not pose any health risk because they were below permitted daily exposure limit and recommended daily allowance except for Fe in 6% of the samples. On the other hand, 34% of the samples had Cu levels above allowable limit where 18% of them were above their permitted daily exposure and recommended daily allowance. In contrast, all samples had concentration of Cr, Hg, and Pb below allowable limits and daily exposure. Whereas, 30% of analyzed samples had levels of Cd above allowable levels, and were statistically correlated with Ca, and Zn essential minerals. Similarly 62% of the samples had levels of As above allowable limits and As levels were associated with Fe and Mn essential minerals.

CONCLUSION

Dietary supplements consumed as essential nutrients for their Ca, Zn, Fe and Mn content should be monitored for toxic metal levels due to their natural geochemical association with these essential metals to provide citizens the safe allowable amounts.

Preliminary investigation of metal and metalloid contamination of homeopathic products marketed in Croatia

BACKGROUND

Due to their popularity as a complementary therapy in many diseases, homeopathic products of animal, vegetable, mineral and chemical origin should be tested for the presence of contaminants to prevent eventual toxic effects.

OBJECTIVE

Thirty samples of homeopathic products were analyzed to estimate possible contamination with potentially toxic elements: Pb, Cd, As, Hg, Cr, Ni and Zn, and to assess human exposure to these metals/metalloid as a consequence of their consumption.

METHODS

Atomic absorption spectrometry was used to determine metal and metalloid concentrations.

RESULTS

Most tested products had very low metal/metalloid levels (below the limit of quantification of the method), but the metal/metalloid levels in the remaining products were in the following ranges (in microg g(-1)): Pb 0.33-1.29 (6 samples), Cd 2.78 (1 sample), As 0.22 (1 sample), Hg 0.02-0.12 (24 samples), Cr 0.40-10.27 (10 samples), Ni 0.43-55.00 (19 samples), and Zn 2.20-27.80 (11 samples). In the absence of regulatory standards for homeopathic products, the obtained results were compared to maximum allowable levels (MALs) as proposed by USP Ad Hoc Advisory Panel. Some analyzed preparations had metal levels above MALs (Pb: 2 samples; Cd: 1 sample; Ni: 2 samples). However, estimated cumulative daily intakes from tested homeopathic products were in all cases lower than permitted daily exposures for all dosage forms.

CONCLUSION

The risk of bioaccumulation of metals/metalloid from the homeopathic medicines seems to be rather low, due to small quantities of those products prescribed to be applied per day, as well as insignificant metal contamination of the majority of tested products. However, the fact that particular formulations were contaminated by metals above MALs indicates potential risk and points to the necessity of regular monitoring of homeopathic products for metal contamination, due to their frequent and mostly unsupervised use.