Dietary intake of toxic and essential trace elements by the children and parents living in Tokyo Metropolitan Area, Japan

Dietary heavy metal(loid)s exposure and prevalence of chronic kidney disease of unknown aetiology (CKDu) in Sri Lanka

Intake of heavy metals and metalloids through the diet is posing a big research challenge in Sri Lanka due to the increasing occurrence of chronic kidney disease of unknown aetiology (CKDu) among the farming communities pursuing their livelihoods in the North Central Province (NCP). Duplicated diet studies were conducted on a sample of 62 individuals comprising adult males, adult females, boys, and girls who were selected following a demographic survey in an area of the NCP where there was a high incidence of CKDu. A health risk assessment was made by analysing the heavy metal(loid)s content in the diet samples, by means of inductively coupled plasma mass spectrometry. Rice and vegetables constituted the main diet in the CKDu prevalent areas, with all gender and age categories adhering to similar daily diet patterns. Results of the heavy metal(loid) analysis of duplicated food intake samples indicated that the amounts of Pb in rice, As and Pb in vegetables, and Cd in fish exceeded the recommended daily limits. Because consumption of rice was much higher than the other food items, the estimated daily intake of Pb exceeded the permissible daily intake of 3.5 µg/kg_BW/day. There were no significant differences between the age and gender categories in respect of estimated daily intake of Pb, which suggested that the entire population of the study area faced the risk of a high level of Pb exposure. Further, the hazard quotient of Pb was greater than 1. Influence of heavy metal(loid)s on the prevalence of CKDu cannot be understated, and as such interventions are required as a matter of urgency to reduce the local population's dietary exposure to heavy metal(loid)s.

Interactions between Environmental Factors and Glutathione S-Transferase (GST) Genes with Respect to Detectable Blood Aluminum Concentrations in Jamaican Children

Aluminum (Al) is a metallic toxicant at high concentrations following natural or unnatural exposures. Dietary intake is considered as the main source of aluminum exposure in children. We used data from 366 typically developing (TD) children (ages 2−8 years) who participated as controls in an age- and sex-matched case−control study in Jamaica. We investigated additive and interactive associations among environmental factors and children’s genotypes for glutathione S-transferase (GST) genes (GSTT1, GSTM1, GSTP1), in relation to having a detectable blood aluminum concentration (BAlC) of >5.0 μg/L, using multivariable logistic regression models. Findings from interactive models revealed that the odds of having a detectable BAlC was significantly higher among children who ate string beans (p ≤ 0.01), whereas about 40% lower odds of having a detectable BAlC was observed in children with higher parental education level, (p = 0.02). A significant interaction between consumption of saltwater fish and GSTP1 in relation to having a detectable BAlC using either co-dominant or dominant genetic models (overall interaction p = 0.02 for both models) indicated that consumption of saltwater fish was associated with higher odds of having a detectable BAlC only among children with the GSTP1 Ile105Val Ile/Ile genotype using either co-dominant or dominant models [OR (95% CI) = 2.73 (1.07, 6.96), p = 0.04; and OR (95% CI) = 2.74 (1.08, 6.99), p = 0.03]. Since this is the first study from Jamaica that reports such findings, replication in other populations is warranted.

Dietary Intake of Toxic Heavy Metals with Major Groups of Food Products—Results of Analytical Determinations

Food contains a complex matrix of various substances, including essential nutrients, non-nutritive substances, and toxins, including metals. The main purpose of the study was to evaluate the contribution of major groups of food products to an overall intake of toxic heavy metals (Cd, Pb, Hg, and Ni) using a combination of the 24-dietary recall technique, the ICP-OES (Inductively Coupled Plasma Optical Emission Spectrometry) method, and chemometric tools. The obtained results reveal that there is a high potential risk of developing nephrotoxicity through the dietary intake of Pb in the case of both genders. The dietary intake determined for other elements (Cd, Hg, and Ni) was far below the limits established by European Food Safety Authority (EFSA). Principal Component Analysis (PCA) supported analytical determinations and revealed that cereals and vegetables were major contributors to a total intake of Cd (39.6 and 17.4% of the total exposure, respectively), Ni (40.4 and 19.3%), and Hg (16.8 and 19.6%), while water and beverages were major dietary sources of Pb (31% of the total daily intake). In contrast, eggs, fats and oils, and milk and dairy products provided the smallest amounts of Cd, Pb, and Ni. Despite containing high amounts of Hg, considering very low consumption, fish were not found to be an important source of this element.

Preliminary assessment of health risks associated with consumption of grapevines contaminated with mining effluents in Turkey: Persistent trace elements and critical raw materials

In this study, some persistent trace elements and critical raw materials were investigated in grapevines contaminated with Pb-Zn mining effluents. The persistent trace elements under certain conditions remain without any change in form in the environment over long periods. The critical raw materials are the ones that have economic importance and have the risks associated with their supply. The health risks of persistent trace elements and critical raw materials in the leaves of grapevine that are consumed by humans were determined. The highest persistent trace elements concentrations followed the order of root > stem > leaf for Mn, Cu, Cd, Ni, and Cr while root > leaf > stem for Zn and leaf > root > stem for Pb. The maximum critical raw material concentrations for Co and V followed the order of root > stem > leaf. For Sb and La, these were leaf > root > stem and root > stem > leaf, respectively. The maximum critical raw materials concentrations for W was leaf > stem = root. The total maximum carcinogenic value was 0.146 for Cd while the total minimum carcinogenic value was 0.0054 for Pb. In this study, potential carcinogenic risk values in terms of ingestion of contaminated soil (Cr, Cd, and Ni) and dietary take of grapevine leaves (Ni, Cr, Cd, and Pb) are higher than acceptable levels (1 × 10^-4  - 1 × 10^-6 ). Maximum cancer risk on human health was determined as dietary intake of grapevine leaves. When hazard quotient for dietary (HQ_die ), hazard quotient for ingestion (HQ_ing ), and hazard quotient for inhalation (HQ_inh ) values ​​of critical raw materials were examined, the maximum values ​​were observed for children. Also, the highest hazard quotient for dermal (HQ_der ) value was determined for men. The hazard index and total hazard index values were >1 for critical raw materials. As a result, values >1 indicated potential non-carcinogenic human health risk associated with the consumption of grapevines contaminated with mining effluents. Actual region-specific exposure estimates for consumption of grapevines, however, were not evaluated. Integr Environ Assess Manag 2022;18:517-527. © 2021 SETAC.

Aluminum reproductive toxicity: a summary and interpretation of scientific reports

Publications addressing aluminum (Al)-induced reproductive toxicity were reviewed. Key details were compiled in summary tables. Approximate systemic Al exposure, a measure of bioavailability, was calculated for each exposure, based on the Al percentage in the dosed Al species, Al bioavailability, and absorption time course reports for the exposure route. This was limited to laboratory animal studies because no controlled-exposure human studies were found. Intended Al exposure was compared to unintended dietary Al exposure. The considerable and variable Al content of laboratory animal diets creates uncertainty about reproductive function in the absence of Al. Aluminum-induced reproductive toxicity in female mice and rats was evident after exposure to ≥25-fold the amount of Al consumed in the diet. Generally, the additional daily Al systemic exposure of studies that reported statistically significant results was greater than 100-fold above the typical human daily Al dietary consumption equivalent. Male reproductive endpoints were significantly affected after exposure to lower levels of Al than females. Increased Al intake increased fetus, placenta, and testes Al concentrations, to a greater extent in the placenta than fetus, and, in some cases, more in the testes than placenta. An adverse outcome pathway (AOP) was constructed for males based on the results of the reviewed studies. The proposed AOP includes oxidative stress as the molecular initiating event and increased malondialdehyde, DNA and spermatozoal damage, and decreased blood testosterone and sperm count as subsequent key events. Recommendations for the design of future studies of reproductive outcomes following exposure to Al are provided.

Lead exposure in an Italian population: Food content, dietary intake and risk assessment

BACKGROUND AND AIM

Lead is a highly toxic heavy metal released into the environment after natural and anthropogenic activities. Excluding populations in occupations where there is possible lead contamination, food is the major source of human exposure. In this study, we determined lead contamination in food and beverages consumed in a Northern Italy community and performed a health risk assessment.

METHODS

We collected a total of 908 food samples and measured lead levels using inductively coupled plasma mass spectrometry. Using a validated food frequency questionnaire, we assessed the dietary habits and estimated daily lead dietary intakes in a sample of 719 adult individuals. We performed risk assessment using a benchmark dose and margin of exposure approach, based on exposure levels for both adverse effect of systolic blood pressure and chronic kidney disease.

RESULTS

Foods with the highest lead levels include non-chocolate confectionery (48.7 µg/kg), leafy (39.0 µg/kg) and other vegetables (42.2 µg/kg), and crustaceans and molluscs (39.0 µg/kg). The estimated mean lead intake was 0.155 µg/kg bw-day in all subjects, with little lower intakes in men (0.151 µg/kg bw-day) compared to women (0.157 µg/kg bw-day). Top food contributors were vegetables, cereals, and beverages, particularly wine. In relation to risk assessment, the estimated dietary intake was lower than levels associated with cardiovascular risk and nephrotoxicity.

CONCLUSIONS

Our study provides an updated assessment of lead food contamination and dietary exposure in a Northern Italian community. The margin of exposure risk assessment approach suggests that risk of detrimental effects due to dietary lead intake is low in the investigated population. Nonetheless, these exposure levels for adverse effects are not reference health standards, and no safety threshold value can be established for lead. As a consequence, other and more subtle adverse effects may still occur in vulnerable and occupationally exposed individuals, particularly in relation to the nervous system.

Health Risk Assessment and Source Apportionment of Mercury, Lead, Cadmium, Selenium, and Manganese in Japanese Women: An Adjunct Study to the Japan Environment and Children's Study

Toxic element pollution is a serious global health concern that has been attracting considerable research. In this study, we elucidated the major routes of exposure to three toxic elements (mercury, cadmium, and lead) and two essential elements (manganese and selenium) through diet, soil, house dust, and indoor air and assessed the potential health risks from these elements on women from the coastal area of Miyagi prefecture, Japan. Twenty-four-hour duplicate diet, house dust, soil, and indoor air samples were collected from 37 participants. Cd, Pb, Mn, and Se concentrations were measured using inductively coupled plasma mass spectrometry, and Hg concentrations using cold vapor atomic absorption spectrometry. We found that soil and house dust were the primary reservoirs of these elements. Diet contributed most strongly to the daily intake of these elements, with mean values of 0.72, 0.25, 0.054, 47, and 0.94 μg/kg/day for Hg, Cd, Pb, Mn, and Se, respectively. The mean hazard quotient of Hg was 1.53, indicating a high potential health risk from Hg exposure in daily lives. The intakes of other elements were below the tolerable limits. Future studies with a larger sample size are warranted to confirm our findings.

Gap analysis of nickel bioaccessibility and bioavailability in different food matrices and its impact on the nickel exposure assessment

The metal nickel is well known to cause nickel allergy in sensitive humans by prolonged dermal contact to materials releasing (high) amounts of nickel. Oral nickel exposure via water and food intake is of potential concern. Nickel is essential to plants and animals and can be naturally found in food products or contamination may occur across the agro-food chain. This gap analysis is an evaluation of nickel as a potential food safety hazard causing a risk for human health. In the first step, the available data regarding the occurrence of nickel and its contamination in food and drinks have been collected through literature review. Subsequently, a discussion is held on the potential risks associated with this contamination. Elevated nickel concentrations were mostly found in plant-based foods, e.g. legumes and nuts in which nickel of natural origin is expected. However, it was observed that dedicated and systematic screening of foodstuffs for the presence of nickel is currently still lacking. In a next step, published studies on exposure of humans to nickel via foods and drinks were critically evaluated. Not including bioaccessibility and/or bioavailability of the metal may lead to an overestimation of the exposure of the body to nickel via food and drinks. This overestimation may be problematic when the measured nickel level in foods is high and bioaccessibility and/or bioavailability of nickel in these products is low. Therefore, this paper analyzes the outcomes of the existing dietary intake and bioaccessibility/bioavailability studies conducted for nickel. Besides, the available gaps in nickel bioaccessibility and/or bioavailability studies have been clarified in this paper. The reported bioaccessibility and bioavailability percentages for different food and drinks were found to vary between <LOD and 83% and between 0 and 30% respectively. This indicates that of the total nickel contained in the foodstuffs only a fraction can be absorbed by the intestinal epithelium cells. This paper provides a unique critical overview on nickel in the human diet starting from factors affecting its occurrence in food until its absorption by the body.

Aluminum and tin: Food contamination and dietary intake in an Italian population

Aluminum and tin are ubiquitous in the environment. In normal biological systems, however, they are present only in trace amounts and have no recognized biological functions in humans. High exposure to these metals can result in adverse health effects such as neurodegenerative diseases. In non-occupationally exposed subjects, diet is the primary source of exposure. In this study, we aimed at estimating dietary aluminum and tin intake in an Italian adult population. We measured aluminum and tin concentrations through inductively-coupled plasma mass spectrometry in 908 food samples. We also estimated dietary intake of these two metals, by using a validated semi-quantitative food-frequency questionnaire administered to 719 subjects (319 men and 400 women) recruited from the general population of the Emilia Romagna region, Northern Italy. We found the highest aluminum levels in legumes, sweets, and cereals, while the highest tin levels were in sweets, meat and seafood. The estimated median daily dietary intake of aluminum was 4.1 mg/day (Interquartile range - IQR: 3.3-5.2), with a major contribution from beverages (28.6%), cereals (16.9%), and leafy vegetables (15.2%). As for tin, we estimated a median intake of 66.8 μg/day (IQR: 46.7-93.7), with a major contribution from vegetables (mainly tomatoes) (24.9%), fruit (15.5%), aged cheese (12.2%), and processed meat (10.4%). This study provides an updated estimate of the dietary intake of aluminum and tin in a Northern-Italy adult population, based on data from a validated food-frequency questionnaire. The intake determined for this population does not exceed the established thresholds of tolerable intake.

Analysis of lead and cadmium in cereal products and duplicate diets of a small group of selected Brisbane children for estimation of daily metal exposure

Exposure to toxic metals such as lead (Pb) and cadmium (Cd) from foods is a concern for young children. The aims of the study were to analyse the levels of Pb and Cd in breakfast cereals, rice products and diets of selected children, and to estimate the daily intakes of Pb and Cd in these children. The samples (n = 82) of ready-to-eat breakfast cereals and rice products (n = 36) were collected and obtained from various markets in Brisbane, Australia. The samples for a duplicate diet study were collected for 3 consecutive days from normal healthy children (n = 15). The analysis was performed using ICP-MS after microwave digestion. The levels of Pb and Cd found in breakfast cereals and rice products ranged from <0.01 to 0.25 mg/kg for Pb and <0.01 to 0.11 mg/kg for Cd. The estimated daily intakes of Pb and Cd in children varied widely and ranged from 0.90 to 11.7 (5.6 ± 3.5 μg/day) for Pb and 0.98 to 9.5 (4.0 ± 2.2 μg/day) for Cd. The study shows low intakes of Pb and Cd in children.

Lead in duplicate diet samples from an academic community

Lead is a naturally occurring element that with the advent of the industrial era became a serious environmental and public health issue. Leaded gasoline, lead based paints, use of lead in plumbing and water pipes, ceramics with lead-containing glazes and tobacco smoke are potential sources of lead exposure for humans. Despite these multiple sources, food is still considered the most important one for the general non-smoking population. Hence, in the present study, the dietary intake of lead was determined in duplicate diet samples provided by 30 participants working or studying at University of Aveiro, Portugal. Pb was detected in all the analysed samples with values ranging between 0.009 and 0.10mgkg^-1 ww which correspond to estimated daily intakes between 0.22 and 3.5μgkg-bw^-1day^-1. Risk estimations disclose that at least 3.3% and 26.7% of the participants might suffer cardiovascular and nephrotoxic effects, respectively.

A pilot duplicate diet study on manganese, selenium and chromium intakes in institutionalised children and adolescents from Guatemala

Hidden hunger occurs in the presence of an otherwise nutritionally or energetically appropriate diet that is deficient in essential vitamins and minerals. Guatemala has the highest rate of child malnutrition in Latin America and the prevalence of hidden hunger is high. The aim of this study was to determine the Mn, Se and Cr dietary intakes in Guatemalan institutionalised children (4-14 years), a population group at high risk of mineral deficiency. For this purpose, the contents of Mn, Se and Cr were analysed in a duplicate diet (for 7 consecutive days) by electrothermal atomisation-atomic absorption spectrophotometry following acid digestion. Mn, Se and Cr intakes from the duplicate diets were in the range of 1·3-2·31 mg/d, 58·7-69·6 µg/d and 6·32-27·57 µg/d, respectively. Mn and Cr values were below current recommended daily intakes. A cereal- and legumes-based diet is habitually consumed by this population. Local vegetables, fruits and nutritional supplements are included daily, but the consumption of fish, meat, eggs and dairy products is very infrequent or negligible. Mean daily energy intake from the 7-d diet was 8418·2 kJ (2012 kcal), with a macronutrient energy distribution of carbohydrates 69·4 %, proteins 12·3 % and fats 18·3 %. Correlations between Mn, Se and Cr intakes and energy and other nutrient intakes were also evaluated. The present findings will help establish new nutritional strategies for this and similar population groups.

Daily dietary intakes of zinc, copper, lead, and cadmium as determined by duplicate portion sampling combined with either instrumental analysis or the use of food composition tables, Shiraz, Iran

Estimation of essential and toxic element intakes is crucial to evaluate the risks of deficiency or toxicity. The purpose of this study was to investigate and also to compare the dietary intakes of zinc (Zn) and copper (Cu) by adults living in Shiraz, Iran, determined by two procedures: duplicate portion sampling of 21 hospital meals combined with either instrumental analysis (voltammetric measurement) or the use of food composition tables (FCTs). The level of exposure to lead (Pb) and cadmium (Cd) was evaluated as well. The daily Zn intakes of both methods were not significantly different and were higher than the RDA values except the value measured by the instrumental analysis which was lower than the RDA established for a male adult. Daily intake of Cu determined by instrumental analysis was significantly lower and closer to RDA for adults compared with the value estimated by FCTs. The dietary intakes of Pb and Cd were 313 and 61% of the respective provisional tolerable weekly intakes (PTWIs), respectively. The accuracy of two methods used for estimation of Zn intake was similar. In the case of Cu, the use of FCTs, in which the influence of environmental conditions and dietary habits of meal preparation is not taken into account, overestimated dietary intake. The risk of zinc deficiency was found in adult males. Moreover, the estimated intake of Pb, but not Cd, could be a cause of concern for Shiraz population. Thus, conducting regular periodic studies to assess the dietary intake of mentioned elements are recommended.

Metals in commonly eaten groceries in Western Australia: a market basket survey and dietary assessment

Children's dietary exposure to metals has received limited attention in Australia. This study undertook a market basket survey and analysed 253 food and beverages for metals. These data were used in conjunction with recent average diet data for children in Western Australia to model dietary metals exposure, with mean metals intakes calculated for boys and girls aged 8, 12, 13 and 16 years. Results show that for some metals, including cadmium, nickel and manganese, dietary intake guidelines have been exceeded in younger children. The mean modelled cadmium intake in children aged 8 years was almost 60% of the World Health Organisation (WHO) guideline and exceeded the European Food Safety Authority (EFSA) guideline. Nickel and manganese intake was higher in younger children than reported in international studies. Modelling based on the 95% percentile of dietary consumption exceeded the respective guidelines or upper level of intake for several of the metals studied. The findings from this study support the need for further investigation into the exposure of children to metals from diet and the health implications of exposure.

Lead and other elements in house dust of Japanese residences--source of lead and health risks due to metal exposure

The levels of 25 elements in house dust collected from 100 general Japanese residences were measured. Factor analysis was applied on the multi-element data to explore source of Pb (median concentration 49.1 mg/kg) in house dust. Six factors were extracted and Pb was found to have great loading on the fifth factor with Sb and Sn, suggesting solder (Sn), and plastic and metals (Sb) may be the sources of Pb in the house dust of Japanese residences. No significant loading was found on soil-related factors indicating non-significant contribution of Pb in track-in soil. Seven heavy metals (Cd, Cu, Mo, Pb, Sb, Sn, and Zn) were found in house dust at >10 times more condensed than crustal abundance. Health risk of these elements to children via the ingestion of house dust was estimated based on the comparison with tolerable daily intake and found to be non-significant for most of the elements.

Usual dietary intakes of selected trace elements (Zn, Cu, Mn, I, Se, Cr, and Mo) and biotin revealed by a survey of four-season 7-consecutive day weighed dietary records in middle-aged Japanese dietitians

We aimed to identify food sources of selected trace elements (Zn, Cu, Mn, I, Se, Cr, Mo) and biotin in the Japanese diet and to assess usual dietary intakes based on the ratios of within-person to between-person variance. Subjects were 98 middle-aged dietitians living in central Japan who participated in a survey of four-season 7 consecutive day weighed diet records. Based on the latest Standard Tables of Food Composition in Japan published in 2010, food sources of selected nutrients were located according to a contribution analysis, and computed usual dietary intakes. Dietary intakes were checked with the Dietary Reference Intakes for Japanese 2010. Prevalence of inadequacy in a group was determined using the Estimated Average Requirement cut-point method. The major contributors to selected trace elements and biotin were not only meat and milk, but also traditional Japanese food items, including rice, tofu and tofu products, fish, seaweed, chicken eggs, fermented soy bean seasonings, and green tea. Medians of usual intakes were estimated for Zn (men 8.9 mg, women 8.4 mg), Cu (1.32 mg, 1.21 mg), Mn (3.73 mg, 3.76 mg), I (312 μg, 413 μg), Se (97 μg, 94 μg), Cr (10 μg, 9 μg), Mo (226 μg, 184 μg), and biotin (51.7 μg, 47.6 μg). The prevalence of inadequacy of dietary intakes was high for Zn, Cu and Cr. Regarding I, the proportion above the Tolerant Upper Level was overestimated based on the crude mean value. We first identified food sources of selected trace elements and biotin in the Japanese diet, and assessed the usual intakes.

Dietary exposure to aluminium and health risk assessment in the residents of Shenzhen, China

Although there are great changes of dietary in the past few decades in China, few are known about the aluminium exposure in Chinese diet. The aim of this study is to systematically evaluate the dietary aluminium intake level in residents of Shenzhen, China. A total of 853 persons from 244 household were investigated their diet by three days food records. Finally, 149 kinds of foods in 17 food groups were selected to be the most consumed foods. From them, 1399 food samples were collected from market to test aluminium concentration. High aluminium levels were found in jellyfish (median, 527.5 mg/kg), fried twisted cruller (median, 466.0 mg/kg), shell (median, 107.1 mg/kg). The Shenzhen residents' average dietary aluminium exposure was estimated at 1.263 mg/kg bw/week which is lower than the PTWI (provisional tolerable weekly intake). But 0-2 and 3-13 age groups have the highest aluminium intake exceeding the PTWI (3.356 mg/kg bw/week and 3.248 mg/kg bw/week) than other age groups. And the main dietary aluminium exposure sources are fried twisted cruller, leaf vegetables and bean products. Our study suggested that even three decades rapid economy development, children in Shenzhen still have high dietary aluminium exposure risk. How to control high dietary aluminium exposure still is a great public health challenge in Shenzhen, China.

Evaluation of seasonal dietary exposure to arsenic, cadmium and lead in schoolchildren through the analysis of meals served by public schools of Ribeirão Preto, Brazil

Dietary exposure to arsenic (AS), cadmium (Cd), and lead (Pb) of Brazilian schoolchildren living in Ribeirão Preto, Brazil, was assessed. Food samples including rice, beans, vegetables, fruits, and meat served daily by public schools were collected as presented in different seasons. Metallic elements were determined by inductively coupled plasma-mass spectrometry (ICP-MS).The main sources of As, Cd, and Pb were found to be rice, vegetables, and pork, respectively. Further, in some food types there were seasonal differences in the concentrations of metallic elements. The mean daily intakes of As, Cd, and Pb based upon the association between food consumption data and the observed concentrations of metals in their diet were 6.9 μg, 0.9 μg, and 0.6 μg for As, Cd, and Pb, respectively. These findings are below the toxicological reference values provided by the European Food Safety Authority (EFSA) and the World Health Organization (WHO).

Human dietary exposure to uranium in catalonia, Spain

The purpose of this study was to determine the daily dietary intake of uranium (U) by the general population of Catalonia, Spain. Uranium concentrations were measured in foods widely consumed by the population living in that autonomous community. Food samples were randomly acquired in 12 representative cities of Catalonia. The dietary intake of U was estimated for various age-gender groups: children, adolescents, adults, and seniors. Fish and seafood was the food group showing the highest U concentrations (0.090 μg/g of fresh weight (fw)), followed by dairy products (0.044 μg/g fw). In contrast, the lowest U levels were found in oils and fats (0.003 μg/g fw), while in tubers and milk, U was not detected in any sample. The estimated dietary intake of U for a standard male adult of 70 kg body weight living in Catalonia was 15.48 μg/day. According to the age/gender of the population, the highest dietary intake of U corresponded to children (20.32 μg/day), while senior females was the subgroup with the lowest U intake (10.04 μg/day). Based on the tolerable daily intake established for U, the current dietary intake of this metal by the general population of Catalonia should not mean health risks for any of the different age/gender groups of consumers.

Lead in the Japanese living environment

Lead has long been known to be a neurotoxic heavy metal, particularly in the context of occupational health. However, its adverse effect on the cognitive development of children at lower exposure levels has only recently received attention. Although the exposure level of contemporary Japanese children is among the lowest in the world, it is desirable to reduce exposure as much as reasonably possible due to the absence of a threshold of exposure for adverse effects. In this review, information on lead levels in milieus of our proximate environment, such as the atmosphere, drinking water, soil, house dust, diet and others, of contemporary Japan was compiled with the aim of updating our knowledge on lead distribution. Monitoring data demonstrates that lead concentrations in the atmosphere and lead intake from food consumption have decreased substantially from the 1970s. Lead was hardly detectable in tap water in a recent nation-wide monitoring survey. To the contrary, elevated lead concentrations were detected in surface soil and house dust in one of the studies on daily exposure to lead from all potential sources, and both of these sources were regarded by the authors as significant contributors of lead exposure to general Japanese children. A similar study indicated that diet is the sole major source of lead for Japanese children. A significant difference was present in the estimated dietary lead intake levels in different studies, resulting in significant discrepancies in the current knowledge on lead in our environment. Further studies are warranted to identify the major source(s) of lead exposure in Japanese children in order to establish an effective countermeasure to reduce lead exposure to children.

Dietary intake of metals by the population of Tarragona County (Catalonia, Spain): results from a duplicate diet study

The daily intakes of arsenic (As), beryllium, cadmium (Cd), cobalt, chromium, copper, mercury (Hg), manganese, nickel, lead (Pb), antimony, tin, thallium, uranium, vanadium, and zinc by an adult population living in Tarragona County (Catalonia, Spain) were determined by the duplicate diet method with a 10-day sampling period. Duplicate diet samples, prepared as per consumption, were collected during September 2010 in 20 restaurants offering a variety of daily menus (breakfast, lunch, and dinner). A total of 200 composite samples, corresponding to 600 individual samples, were prepared for trace elements analyses, which were carried out by inductively coupled plasma mass spectrometry. The results were compared with data from previous total diet studies (TDS) recently performed in the same geographical area. Notable differences in the intake of the toxic elements As, Cd, Hg, and Pb were found depending on the method used. It is concluded that both the duplicate diet method and the TDS may provide important and useful information to estimate human exposure to metals through the diet and their derived health risks. However, for comparison between surveys or for establishing temporal trends in the intake of metals, it seems to be recommendable to use always the same method. Notwithstanding, if the interest is only to know whether the intake of a certain element is below the tolerable intake, both methods are useful.

The estimated daily manganese intake of Korean children aged 11-12

The purpose of this study was to estimate the daily manganese (Mn) intake of Korean children. This study was done using a three-day dietary intake survey of 257 Korean children (boys 123; girls 134). The Mn intake values were calculated based on a database that provides the Mn content of the frequently consumed Korean foods, alongside the food composition table provided by the Korean National Rural Living Science Institute. The average age, height, weight and body mass index of our subjects were 11.9 years, 155.4 cm, 48.9 kg and 20.2 kg/m² in boys and 11.9 years, 154.1 cm, 43.5 kg and 18.3 kg/m² in girls. The average daily energy intakes were 2,249.2 kcal in boys and 2,044.5 kcal in girls. Boys consumed significantly more Mn than girls, based on intake estimates of 4,585.3 µg (117.6% of adequate intake) and 4,029.3 µg (117.1% of adequate intake), respectively (P < 0.001). Boys had a Mn intake of 2,041.1 µg per 1,000 kcal of energy consumption, whereas for girls this was at 1,983.9 µg per 1,000 kcal. Neither group exceeded the tolerable upper intake level for Mn. The major food groups which contributed to Mn intake in our subjects were cereals (50.8%), vegetables (21.0%), seasonings (8.9%), and pulses (7.7%). Notably, boys derived a higher Mn intake through cereals and vegetable than did girls (P < 0.001, P < 0.05). The key food sources of Mn, in descending order, were rice, soybean curd, kimchi, black rice and cereals. We propose that the results of our study may be used as a basis for follow-up studies that examine the Mn intake of children.

Betel quid chewing as a source of manganese exposure: total daily intake of manganese in a Bangladeshi population

BACKGROUND

A relationship between betel quid chewing in Bangladeshi populations and the development of skin lesions and tremor has been previously reported, for people exposed to high levels of arsenic (As) through drinking contaminated groundwater. Exposure to manganese (Mn) is also known to induce neurotoxicity and levels of Mn in Bangladeshi groundwater are also high. The present study evaluates betel quid chewing as an overlooked source of Mn exposure in a Bangladeshi population.

METHODS

Inductively coupled plasma mass spectrometry (ICP-MS) was used to determine (1) urinary Mn levels for 15 chewers and 22 non-chewers from the ethnic Bangladeshi community in the United Kingdom, and (2) Mn levels in betel quids, its individual components and other Bangladeshi foods.

RESULTS

Betel quid chewers displayed a significantly higher (P = 0.009) mean Mn concentration in urine (1.93 μg L(-1)) compared to non-chewers (0.62 μg L(-1)). High levels of Mn were detected in Piper betel leaves with an overall average of 135 mg kg(-1) (range 26 -518 mg kg(-1)). The mean concentration of Mn in betel quid was 41 mg kg(-1) (SD 27) and the daily intake of Mn in the Bangladeshi population was estimated to be 20.3 mg/day. Chewing six betel quids could contribute up to 18% of the maximum recommended daily intake of Mn.

CONCLUSION

We have demonstrated that Mn in betel quids is an overlooked source of exposure to Mn in humans. Chewers display a 3.1 fold increased urinary Mn concentration compared to non-chewers. The practice of betel quid chewing contributes a high proportion of the maximum recommended daily intake of Mn, which could make chewers in Bangladesh more vulnerable to Mn neurotoxicity.

Dietary intake of aluminum in a Spanish population (Canary Islands)

The aim of this study was to analyze the aluminum content in foods and beverages most commonly consumed by the Canary Island population to determine the dietary intake of this metal throughout the Canary Islands as a whole and in each of the seven islands (Gran Canaria, Lanzarote, Fuerteventura, Tenerife, La Palma, La Gomera, and El Hierro). Four hundred and forty samples were analyzed by ICP-OES. Estimated total intake of aluminum for the Canary population was 10.171 mg/day, slightly higher than the provisional tolerable weekly intake (PTWI; 10 mg/day for a person weighing 70 kg). Aluminum intake by age and sex of the Canary Island population was also determined and compared values from other populations, both national and international.

Dietary intake of lead and cadmium by children and adults - Result calculated from dietary recall and available lead/cadmium level in food in comparison to result from food duplicate diet method

The dietary intakes of lead and cadmium by 30 children and 30 adults living in Jinhu area in China were determined by the duplicate method with a 3-day sampling period. Dietary recall and available lead/cadmium level in food were also used to calculate dietary intakes. Lead intakes based on duplicate method were 15.66μg(kg(bw))(-1)week(-1) for children and 8.83μg(kg(bw))(-1)week(-1) for adults. Cadmium intakes were 2.07μg(kg(bw))(-1)week(-1) for children and 1.49μg(kg(bw))(-1)week(-1) for adult. The results from the dietary record method were as follows: lead intakes were 11.84μg(kg(bw))(-1)week(-1) for children and 7.70μg(kg(bw))(-1)week(-1) for adult. Cadmium intakes were 2.20μg(kg(bw))(-1)week(-1) for children and 1.44μg(kg(bw))(-1)week(-1) for adults. Children's dietary intakes were higher than those of adults'. The results of the dietary intakes calculated from two methods did not have significant difference. Compared to the FAO/WHO PTWIs for lead and cadmium, the average lead and cadmium dietary intakes are all below PTWIs. It was concluded that dietary record method can give comparatively accurate result for lead and cadmium dietary intakes compared with duplicate method. The average lead and cadmium dietary intakes for children and adults in Jinhu area are considered safe. However, the high level of dietary lead and cadmium intakes of children in this area deserves our attention.

Iron, zinc, manganese and copper intakes in Japanese children aged 3 to 5 years

This study aimed to measure and evaluate the intakes for the four trace elements of Fe, Zn, Mn, and Cu in 3- to 5-y-old Japanese preschool children. The study group consisted of a total of 90 3- to 5-y-old children living in Yokkaichi, Mie, Japan. Diet samples were collected by the duplicate-portion technique on 3 d at three different seasons between summer in 1999 and winter in 2000. The medians of annual mean daily intakes (25th-75th percentile) of Fe, Zn, Mn, and Cu in the 3- to 5-y-old children were 3.1 mg (2.4 to 3.6), 4.0 mg (3.4 to 4.7), 1.3 mg (1.1 to 1.6), and 0.45 mg (0.35 to 0.56), respectively. The annual mean value of the total daily diet intake had significant correlations with the Fe, Zn, Mn and Cu intakes (Spearman's r=0.55, 0.67, 0.58, and 0.55, respectively; p<0.001 for all). There were significant correlations between each mineral intake. The Zn and Mn intakes had differences among ages (p=0.003 and 0.005, respectively) and the Zn intake significantly differed between boys and girls (p=0.031). The proportion of subjects whose Mn intake was the AI or less was 82%, and the proportions of subjects whose Fe, Zn, and Cu intakes were the estimated average requirements (EARs) or less were 72, 83, and 13%, respectively. Many Japanese children are deficient in Fe and Zn compared with the dietary reference intakes (DRIs). However, data in a balance study examining intakes and excretion of trace minerals are insufficient in children and DRIs for trace elements may change in future.

Dietary intake of nickel and zinc by young children--results from food duplicate portion measurements in comparison to data calculated from dietary records and available data on levels in food groups

The daily dietary intake of nickel (Ni) and zinc (Zn) by 42 young children, 21 boys and 21 girls, from 4 to 7 years of age, living in urban and rural areas of Germany and having different food consumption behaviour, was determined by the duplicate method with a 7-day sampling period. Dietary records were also kept by the children's parents for the 7-day sampling period. Individual reported food items were identified, assigned to food groups and, together with known Ni and Zn concentrations of foodstuffs, daily intake rates were calculated. The same method was used for calculations of the energy, fat, protein and carbohydrate intake rates. The levels in the food duplicates, determined by atomic absorption spectrometry, were in the range of 69-2000 microg Ni/kg(dry weight) (geometric mean (GM): 348) and 7.1-43 mg Zn/kg(dry weight) (GM: 17.5). Daily intake rates based on the 294 individual food duplicate analyses were 12-560 microgNi/d (GM: 92.3) and 1.5-11 mgZn/d (GM: 4.63). The results from the dietary records were 35-1050 microg Ni/d (GM: 123) and 1.7-15 mg Zn/d (GM: 5.35). The results of the daily intake rates from both methods showed a correlation with regard to Zn (r=0.56), but no correlation was found between either the Ni intake rates determined with both methods or between the Ni intake rates measured by the duplicate method and calculated intake rates from the dietary records of energy, fat, protein, carbohydrates or drinking water. In the case of nickel, the discrepancies between the methods lead one to suppose that the main factors influencing Ni intake by food are not directly caused by easily assessable food ingredients themselves. It is possible that other factors, such as contaminated drinking water or the transition of Ni from kettles or other household utensils made from stainless steel into the food, may be more relevant. In addition there are some foodstuffs with great variations in concentrations, often influenced by the growing area and environmental factors. Further, some food groups naturally high in Nickel like nuts, cocoa or teas might not have been kept sufficient within the records. In summary, the dietary record method gave sufficient results for Zn, but is insufficient for Ni. Based on the food duplicate analysis, children living in urban areas with consumption of food products from a family-owned garden or the surrounding area and/or products from domestic animals of the surrounding area had about one-third higher Ni levels in their food than children either living in an urban area or children consuming products exclusively from the supermarket. Only slight differences were found with regard to Zn. Compared to the recommendations of the German Society of Nutrition (DGE) (25-30 microgNi/d and 5.0 mgZn/d), the participants of the study had a clearly increased Ni and, in view of the geometric mean value, a nearly adequate Zn intake. Health risks are especially given with regard to the influence of nickel intake by food on dermatitis for nickel-sensitive individuals.

Dietary exposure estimates of twenty-one trace elements from a Total Diet Study carried out in Pavia, Northern Italy

The significant role of trace elements in human health is well documented. Trace elements are those compounds that need to be present in the human diet to maintain normal physiological functions. However, some microelements may become harmful at high levels of exposure, or, on the other hand, may give rise to malnutrition, when their exposure is too low. The aim of the present study was to provide a reliable estimate of the dietary exposure of twenty-one trace elements in a Northern Italian area. For this purpose, trace element analyses were undertaken on total diet samples collected from a university cafeteria in Pavia, Northern Italy. The average daily exposure for the adult people was calculated on the basis of food consumption frequency, portion size and trace element levels in foodstuffs. The mean exposure values satisfy the Italian RDA for all the essential trace elements, except for Fe exposure in females, and are well below the Provisional Tolerable Daily Intake for all the toxic compounds, showing that the probability of dietary exposure to health risks is overall small. As far as Fe exposure is concerned, a potential risk of anaemia in the female adult population should be considered, then studies aimed at evaluating the Fe nutritional status of adult Italian women should be addressed. In conclusion, while not excluding the possibility that the daily exposure determined in the present study may not be representative of the population as a whole, this study provides a good estimate of the Italian adult consumer exposure to twenty-one trace elements.

Time to re-evaluate the guideline value for manganese in drinking water?

OBJECTIVE

We reviewed the scientific background for the current health-based World Health Organization (WHO) guideline value for manganese in drinking water.

DATA SOURCES AND EXTRACTION

The initial starting point was the background document for the development of the WHO's guideline value for manganese in drinking water as well as other regulations and recommendations on manganese intake levels. Data referred to in these documents were traced back to the original research papers. In addition, we searched for scientific reports on manganese exposure and health effects.

DATA SYNTHESIS

The current health-based guideline value for manganese in drinking water is based partly on debatable assumptions, where information from previous reports has been used without revisiting original scientific articles. Presently, preparation of common infant formulas with water containing manganese concentrations equivalent to the WHO guideline value will result in exceeding the maximum manganese concentration for infant formula. However, there are uncertainties about how this maximum value was derived. Concurrently, there is increasing evidence of negative neurologic effects in children from excessive manganese exposure.

CONCLUSIONS

The increasing number of studies reporting associations between neurologic symptoms and manganese exposure in infants and children, in combination with the questionable scientific background data used in setting the manganese guideline value for drinking water, certainly warrant a re-evaluation of the guideline value. Further research is needed to understand the causal relationship between manganese exposure and children's health, and to enable an improved risk assessment.