Cadmium Intake Research Articles

Toxic Elements in Commercial Infant Food, Estimated Dietary Intake, and Risk Assessment in Poland

This paper presents results of heavy metals determination in infant foods available in Poland during a monitoring programme in 2009-13. This study investigated levels of lead, cadmium, arsenic, and mercury in infant formulae and other infant foods intended for consumption during the first 6 to 12 months of life, and an intake of heavy metals was assessed. Food consumption data based on the artificial feeding scheme of infants established by the Mother and Child Institute in Poland were taken into account to estimate dietary exposure. The reported levels of elements in infant foods are comparable with contamination of such products in other countries. The mean values for lead do not exceed 0.013 mg/kg (90 th percentile, 0.028 mg/kg). Lead levels in infant formulae (as sold, mainly powder) did not exceed 0.010 mg/kg, while mean contamination was 0.005 mg/kg. The highest mean cadmium level of 0.010 mg/kg was reported in vegetable meal (90 th percentile, 0.017 mg/kg); in infant formulae (undiluted) milk-based it was below 0.003 mg/kg, and for soya-based it was 0.009 mg/kg. Arsenic and mercury contents – highest in fish-based infant foods – did not exceed 0.18 mg/kg and 0.013 mg/kg, respectively. In rice products for infants arsenic did not exceed 0.14 mg/kg. The estimated mean lead exposure was from 0.09 μg/kg b.w. per day for 6-month-old infants to 0.53 μg/kg b.w. per day for 1-year-old children, which was approximately 17% and equal to the respective Benchmark Dose Lower Confidence Limit (BMDL01) established by the European Food Safety Authority (EFSA) at 0.50 μg/kg b.w. per day. Mean exposure to cadmium ranges from 0.02 to 0.4 μg/kg b.w. per day, and for 12-month-old infants can slightly exceed the tolerable weekly intake (TWI) value established by EFSA. Dietary cadmium intake represents 2.5-47% of the provisional tolerable monthly intake (PTMI) value established by the Joint FAO/WHO Expert Committee of Food Additives (JECFA). Intake of arsenic and mercury was below respective reference value. Calculated mean dietary exposure to arsenic for children under 1 year old was between 0.11 and 0.99 μg/kg b.w. per day (4-33% BMDL0.5 value), and to methylmercury 0.01-0.08 μg/kg b.w. per day (7-41% of the TWI value for methylmercury).

Dietary exposure to cadmium, lead and nickel among students from south-east Poland.

The dietary intake of cadmium, lead and nickel was determined among students from three universities in the city of Lublin in south-east Poland to assess the levels of exposure to these contaminants, compared to PTWI and TDI values. The study was performed in 2006–2010 and involved 850 daily food rations of students. The technique of 24-hour dietary recall and diet duplicates was used. Cadmium, lead and nickel complexes with ammonium-pyrrolidindithiocarbamate were formed and extracted to the organic phase with 4-methylpentan-2-one–MIBK, in which their content was measured by flame atomic absorption spectrometry. The highest intake of the elements studied was observed in 2008. The data show that in none of the cases, the level of intake reached 70% of PTWI/TDI values, and thus the risk of developing diseases related to high exposure to these toxic metals absorbed from foodstuffs was low. The parameters of methods were checked during determinations by adding standard solutions to the samples before mineralization and by using two reference materials: Total diet ARC/CL HDP and Bovine muscle RM NIST 8414. The dietary exposure to lead and cadmium has significantly decreased in recent years, whereas the exposures to nickel remains on a stable level.

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.

Microphthalmia-associated transcription factor as the molecular target of cadmium toxicity in human melanocytes

Dietary intake of cadmium is inevitable, causing age-related increase in cadmium accumulation in many organs, including hair, choroid and retinal pigment epithelium (RPE). Cadmium has been implicated in the pathogenesis of hearing loss and macular degeneration. The functions of cochlea and retina are maintained by melanocytes and RPE, respectively, and the differentiation of these pigment cells is regulated by microphthalmia-associated transcription factor (MITF). In the present study, we explored the potential toxicity of cadmium in the cochlea and retina by using cultured human melanocytes and human RPE cell lines. MITF consists of multiple isoforms, including melanocyte-specific MITF-M and widely expressed MITF-H. Levels of MITF-M protein and its mRNA in human epidermal melanocytes and HMV-II melanoma cells were decreased significantly by cadmium. In parallel with the MITF reduction, mRNA levels of tyrosinase, the key enzyme of melanin biosynthesis that is regulated by MITF-M, were also decreased. In RPE cells, however, the levels of total MITF protein, constituting mainly MITF-H, were not decreased by cadmium. We thus identify MITF-M as the molecular target of cadmium toxicity in melanocytes, thereby accounting for the increased risk of disability from melanocyte malfunction, such as hearing and vision loss among people with elevated cadmium exposure.

Scalp hair and blood cadmium levels in association with chewing gutkha, mainpuri, and snuff, among patients with oral cancer in Pakistan.

It has been reported that smokeless tobacco (SLT) chewing can lead to caners of oral cavity. In this study, the relationship between cadmium exposure via consumption of different SLT products by patients with oral cancer with related to referents belongs to different cities of Pakistan are investigated. The cadmium in different types of SLT products (gutkha, mainpuri and snuff) consumed by studied population and biological samples (scalp hair and blood) of cancerous and healthy subjects were analyzed. Both referents and patients with cancer have same age group (ranged 30-60years), socioeconomic status, localities, and dietary habits. The concentrations of cadmium in SLT products and biological samples were measured by electrothermal atomic absorption spectrophotometer after microwave-assisted acid digestion. The validity and accuracy of the methodology were checked by certified reference materials. It was estimated that 10g intake of different types of gutkha, mainpuri, and snuff could contribute, 18-40%, 15.7-33.6%, and 14-68% of the provisional maximum tolerable daily intake of cadmium, respectively for adults (60kg). The results of present study showed that the mean value of cadmium was significantly higher in scalp hair and blood samples of patients with oral cancer as compared to those results obtained for referents (P<0.001). The high exposure of cadmium due to consuming different SLT products may have synergistic effects with other risk factors associated for oral cancer.

Dietary Cadmium Intake and Risk of Prostate Cancer in Middle-Aged Danish Men

Background. The toxic metal cadmium is classified as a human lung carcinogen. Though cadmium has no physiological role, increasing evidence suggests that cadmium may mimic steroid hormones. This du...

Physiologically-based toxicokinetic model for cadmium using Markov-chain Monte Carlo analysis of concentrations in blood, urine, and kidney cortex from living kidney donors.

The health effects of low-level chronic exposure to cadmium are increasingly recognized. To improve the risk assessment, it is essential to know the relation between cadmium intake, body burden, and biomarker levels of cadmium. We combined a physiologically-based toxicokinetic (PBTK) model for cadmium with a data set from healthy kidney donors to re-estimate the model parameters and to test the effects of gender and serum ferritin on systemic uptake. Cadmium levels in whole blood, blood plasma, kidney cortex, and urinary excretion from 82 men and women were used to calculate posterior distributions for model parameters using Markov-chain Monte Carlo analysis. For never- and ever-smokers combined, the daily systemic uptake was estimated at 0.0063 μg cadmium/kg body weight in men, with 35% increased uptake in women and a daily uptake of 1.2 μg for each pack-year per calendar year of smoking. The rate of urinary excretion from cadmium accumulated in the kidney was estimated at 0.000042 day(-1), corresponding to a half-life of 45 years in the kidneys. We have provided an improved model of cadmium kinetics. As the new parameter estimates derive from a single study with measurements in several compartments in each individual, these new estimates are likely to be more accurate than the previous ones where the data used originated from unrelated data sets. The estimated urinary excretion of cadmium accumulated in the kidneys was much lower than previous estimates, neglecting this finding may result in a marked under-prediction of the true kidney burden.

Human Health Risks Derived from Dietary Exposure to Toxic Metals in Catalonia, Spain: Temporal Trend

The present study was aimed at estimating the current (2012) dietary intake of arsenic (As), cadmium (Cd), mercury (Hg), and lead (Pb) by the population of Catalonia, Spain. The temporal trends with respect to previous surveys, performed in 2000, 2005, and 2008, were also determined. For that purpose, metal concentrations were analyzed in a number of widely consumed foodstuffs. A speciation study was also conducted by experimentally determining the levels of inorganic As (InAs) and methylmercury (MeHg) in the same food items. Furthermore, the dietary intake of those metals and species was calculated both deterministically and probabilistically by considering two food consumption surveys: ENCAT and ENIDE, representative of the Catalan and Spanish populations, respectively. An important temporal decrease of the dietary intake was noted for most elements, irrespective of the age-gender population group. Considering data for a male adult, the current dietary intake of As, InAs, Cd, Hg, MeHg, and Pb was estimated in 216, 2.6, 8.7, 10, 7.3, and 8.4 μg/day, respectively, being these values lower than the respective provisional tolerable weekly intakes (PTWIs) or benchmark dose lower confidence limits (BMDLs). Moreover, new calculations by means of ENIDE survey indicated similar results to those previously obtained by ENCAT, with the exception of MeHg, whose intake exceeded the maximum recommended values for some part of the population. Although our data are similar to those frequently found in other European countries, the important intake of MeHg, which is linked to the high consumption of fish and shellfish, deserves further investigation.

The influence of cadmium on physiological processes and productivity of Poaceae plants

An analysis of literary data on the intake of cadmium in Poaceae plants and its accumulation in the under- and aboveground organs of these plants was performed. Information about modern concepts of cadmium transport in plant tissues and cells and of some mechanisms limiting its intake to leaves and grain of cereals is analyzed. The influence of cadmium on the main physiological processes and plant productivity is described. Based on the analysis carried out, some cultivated species of cereals and physiological processes are spread over a range according to their tolerance to cadmium.

Dietary cadmium intake and risk of breast, endometrial and ovarian cancer in Danish postmenopausal women: a prospective cohort study.

PurposeCadmium is a human lung carcinogen and possesses estrogen-like activity. This combination of carcinogenic and estrogenic activity makes cadmium a contaminant of high concern for hormone-related cancers. Diet and smoking are the main sources of cadmium exposure. The aim of this study was to investigate the association between dietary cadmium intake and risk of breast, endometrial and ovarian cancer in Danish postmenopausal woman.MethodsWe estimated dietary cadmium intake in the Diet, Cancer and Health cohort at enrolment 1993-97. The estimates were based on food frequency questionnaires and cadmium contents in all foods. Among 23,815 postmenopausal women we identified 1390 breast, 192 endometrial, and 146 ovarian cancer cases from enrolment through December 31, 2010 using the Danish Cancer Registry. Cox regression was used to analyse the association between dietary cadmium intake and cancer risk.ResultsMean dietary cadmium intake was 14 µg/day. Cadmium was not associated with breast cancer, incidence rate ratio (IRR) = 0.99, 95% confidence interval (CI): 0.87–1.13 per 10 µg higher dietary cadmium intake/day; endometrial cancer, IRR = 1.08, 95% CI: 0.76–1.53; or ovarian cancer, IRR = 1.15, 95% CI: 0.78–1.70. We found a positive association between cadmium and endometrial cancer for the women with BMI<25 (IRR = 1.50, 95% CI: 0.94–2.39), whereas an inverse association was seen for the women with BMI≥25 (IRR = 0.69, 95% CI: 0.42–1.12); p value for interaction = 0.02.ConclusionsOur study does not indicate that our estimated dietary cadmium intake is associated with hormone-related cancers in women.

Removal of cadmium by Lactobacillus kefir as a protective tool against toxicity.

The aim of this work was to evaluate the capacity of Lactobacillus kefir strains to remove cadmium cations and protect eukaryotic cells from cadmium toxicity. Lb. kefir CIDCA 8348 and JCM 5818 were grown in a 1/2 dilution of MRS broth supplemented with Cd(NO3)2 ranging 0 to 1 mM. Growth kinetics were followed during 76 h at 30 °C by registering optical density at 600 nm every 4-10 h. The accumulated concentration of cadmium was determined on cultures in the stationary phase by atomic absorption. The viability of a human hepatoma cell line (HepG2) upon exposure to (a) free cadmium and (b) cadmium previously incubated with Lb. kefir strains was evaluated by determining the mitochondrial dehydrogenase activity. Lb. kefir strains were able to grow and tolerate concentrations of cadmium cations up to 1 mM. The addition of cadmium to the culture medium increased the lag time in all the concentrations used. However, a decrease of the total biomass (maximum Absorbance) was observed only at concentrations above 0.0012 and 0.0011 mM for strains CIDCA 8348 and JCM 5818, respectively. Shorter and rounder lactobacilli were observed in both strains upon microscopic observations. Moreover, dark precipitates compatible with intracellular precipitation of cadmium were observed in the cytoplasm of both strains. The ability of Lb. kefir to protect eukaryotic cells cultures from cadmium toxicity was analysed using HepG2 cells lines. Concentrations of cadmium greater than 3×10(-3) mM strongly decreased the viability of HepG2 cells. However, when the eukaryotic cells were exposed to cadmium pre-incubated 1 h with Lb. kefir the toxicity of cadmium was considerably lower, Lb. kefir JCM 5818 being more efficient. The high tolerance and binding capacity of Lb. kefir strains to cadmium concentrations largely exceeding the tolerated weekly intake (TWI) of cadmium for food (2.5 μg per kg of body weight) and water (3 μg/l) addressed to human consumption, is an important added value when thinking in health-related applications.

Cadmium exposure from food: the German LExUKon project

Cadmium is a very toxic contaminant with food being the major source of exposure for the general public. The second German food consumption survey (Nationale Verzehrsstudie II – NVS II) with about 20 000 participants (15 371 for dietary history interviews used for this study) allowed for an updated exposure assessment for the German population. Based on these comprehensive data, information on the consumption of 545 individual food items by the German population was generated. Cadmium concentrations in food were compiled from the German food monitoring programme, European countries’ authority programmes and the published literature, covering the years from 1993 to 2008, and were multiplied with consumption data to obtain estimates of cadmium intake from food. Consumption-weighted mean cadmium concentrations per main food group were highest for cereals, followed by oily seeds & fruits, and vegetables. Due to both high consumption and considerable occurrence of cadmium, cereals and vegetables contributed most to the intake of the general public, followed by the main groups beverages, fruits & nuts, and dairy products (including milk). Cadmium intake from food was estimated to be 1.46 and 2.35 µg kg–1 bw week–1 for average and high-end consumers, respectively. This corresponds to 58% for average and 95% for high-end consumers, respectively, of a reference value derived from a recent health risk evaluation performed by EFSA, using the benchmark approach. Uncertainties in these estimates pertain to the influence of values below the limit of quantification and some foods not considered due to lacking occurrence data. In conclusion, the estimated cadmium intake of the German population from food is still close to health-based reference values. Further efforts to reduce cadmium intake are required.

Relationship among the birth defect and heavy metal such as arsenic, cadmium, zinc and copper

The incidence of birth defect in China is still high, which is not only affected by genetic factors, but also affected by heavy metals in surrounding that prejudices foetus' normal development. Heavy metal is a kind of inorganic pollutants with high toxicity. Excessive intake of lead, cadmium, arsenic or mercury, and the insufficient intake of zinc, calcium and copper may both lead to at least 1 kind of birth defect. The interactions between heavy metals also affect the outcomes of pregnancy. This paper reviewed different relationships between heavy metals and birth defect recording to relevant achievements such as animal experimentations and epidemiologic study made by researches from at home and abroad in recent years. It is advised to intake adequate zinc and copper and avoid being exposed to harmful metals to make sure the effective reduction of the incidences of birth defects. This paper will also point out the direction of future research about the relationship among the birth defects and heavy metal. Key words: Heavy metal; Pregnancy; Birth defect

Evaluation of Content and Estimation of Daily Intake of Cadmium and Lead in Several Varieties of Potatoes (Solanum tuberosum L.) Cultivated in the Canary Islands (Spain)

Monitoring the metal content in foods such as potatoes is an important aspect of food safety and regulation. Samples of nine varieties of potatoes (73 samples of local potatoes and 77 samples of imported potatoes) were randomly obtained from supermarkets, farmers markets, and farmer plots in Tenerife (Canary Islands, Spain). The edible portion (pulp) was the only part considered for analysis because Spaniards traditionally eat only peeled potatoes. Cadmium (Cd) and lead (Pb) were determined using graphite furnace atomic absorption spectrometry. Cd concentrations ranged from 0.006 mg/kg in the Cara and Negra varieties to 0.019 mg/kg in the Bonita variety, and Pb concentrations ranged from 0.007 mg/kg in the Up-to-date variety to 0.023 mg/kg in the Recara variety. The mean concentrations of Cd (0.01 mg/kg) and Pb (0.014 mg/kg) were below the limits established by European regulations for potatoes (0.1 mg/kg of wet weight for each metal). Based on a mean consumption of 143.2 g of potato per person per day for the Canary Islands population, the mean daily intakes of Cd (0.015 mg/day) and Pb (0.023 mg/day) were below the legislated respective tolerable weekly intakes. Thus, the samples analyzed were considered safe to eat with regard to the metal concentrations found.

Dietary Cadmium Exposure and Risk of Breast, Endometrial, and Ovarian Cancer in the Women’s Health Initiative

Background: In vitro and animal data suggest that cadmium, a heavy metal that contaminates some foods and tobacco plants, is an estrogenic endocrine disruptor. Elevated estrogen exposure is associated with breast, endometrial, and ovarian cancer risk.Objectives: We examined the association between dietary cadmium intake and risk of these cancers in the large, well-characterized Women’s Health Initiative (WHI).Methods: A total of 155,069 postmenopausal women, 50–79 years of age, who were enrolled in the WHI clinical trials or observational study, participated in this study. We estimated dietary cadmium consumption by combining baseline food frequency questionnaire responses with U.S. Food and Drug Administration data on food cadmium content. Participants reported incident invasive breast, endometrial, or ovarian cancer, and WHI centrally adjudicated all cases through August 2009. We applied Cox regression to estimate adjusted hazard ratios (HRs) and 95% CIs for each cancer, comparing quintiles of energy-adjusted dietary cadmium intake.Results: Over an average of 10.5 years, 6,658 invasive breast cancers, 1,198 endometrial cancers, and 735 ovarian cancers were reported. We observed no statistically significant associations between dietary cadmium and risk of any of these cancers after adjustment for potential confounders including total dietary energy intake. Results did not differ in any subgroup of women examined.Conclusions: We found little evidence that dietary cadmium is a risk factor for breast, endometrial, or ovarian cancers in postmenopausal women. Misclassification in dietary cadmium assessment may have attenuated observed associations.Citation: Adams SV, Quraishi SM, Shafer MM, Passarelli MN, Freney EP, Chlebowski RT, Luo J, Meliker JR, Mu L, Neuhouser ML, Newcomb PA. 2014. Dietary cadmium exposure and risk of breast, endometrial, and ovarian cancer in the Women’s Health Initiative. Environ Health Perspect 122:594–600; http://dx.doi.org/10.1289/ehp.1307054

External costs of cadmium emissions to soil: a drawback of phosphorus fertilizers

Abstract In this study the Impact-Pathway Approach methodology was applied for monetary valuation of health impacts due to cadmium emitted to soil as a micro-pollutant present in phosphorus fertilizers. Due to the high persistency of cadmium in soil, and high soil-to-plant transfer rates, humans are exposed to cadmium through their diet causing potential adverse health impacts. Future scenarios for cadmium emissions to soil via agricultural applications of inorganic and organic fertilizers in Denmark were defined. A simplified fate and speciation model allowed the increase in soil cadmium concentration to be calculated for each scenario. Human exposure was determined based on soil-crop bioconcentration factors for cadmium and dietary intake rates of Danish food crops. Updated dose–response functions linking lifetime cadmium intake to the probability of developing cadmium-induced renal disease and osteoporosis were applied. These impacts were converted into monetary values by using the EU standard value of a life-year adjusted for quality of life experience. Annualized cost per unit of phosphorus and cadmium are presented, discounted and undiscounted, for comparison. Application of struvite (magnesium ammonium phosphate) and mineral fertilizer produced the lowest external health costs, followed by the fertilizer products wastewater sludge and pig manure. The external cost estimates produced in this study could be used to design economic policy instruments to encourage use of cleaner fertilizer products.

Content of toxic and essential metals in recrystallized and washed table salt in Shiraz, Iran

BackgroundTable salt is the most commonly used food additive. Since most of the salt consumed in Iran comes from mines, contamination with heavy metals is a health concern. The commonest salt purification method in Iran is washing with water. But recently, some industries have turned to recrystallization method. The present study aimed to determine the level of essential and non-essential heavy metals in the table salt refined with recrystallization and washing methods.MethodsThirty eight pre-packed salt samples were directly collected from retail market in Shiraz (22 samples refined with recrystallization method and 16 with washing method). The level of lead, cadmium, copper, zinc, nickel and cobalt was determined using Voltammetric method. Daily intakes of lead and cadmium as well as their weekly intakes were calculated.ResultsThe levels of lead, cadmium, copper, zinc, nickel and cobalt in recrystallized samples were 0. 30 ± 0.26, 0.02 ± 0.02, 0.11 ± 0.06, 0.34 ± 0.22, 0.15 ± 0.19 and 0.008 ± 0.007 μg/g, respectively, and also 0.37 ± 0.27, 0.017 ± 0.021, 0.19 ± 0.18, 0.37 ± 0.20, 0.13 ± 0.23 and 0.037 ± 0.06 μg/g in washed salt samples. The calculated weekly intake of lead and cadmium was 0.216 and 0.014 μg/kg, respectively for the recrystallized and 0.2653 and 0.0119 μg/kg for the washed salts.ConclusionAll values for toxic metals were lower than the permitted maximum for human consumption as prescribed by Codex and Institute of Standards and Industrial Research of Iran. Only 0.8652-1.0612% of lead and 0.17-0.2% of cadmium PTWIs are received via salt consumption weekly.

Studying capability of soil cadmium phytoremediation by sorghum in the presence of mycorrhiza fungi

This study was designed to investigate the capability of Sorghum plant to purify the cadmium-contaminated soil in the presence of mycorrhiza fungi. This study was performed in Farm of Agriculture Research of Saveh Islamic Azad University as a factorial experiment based on randomized complete blocks design with three replications. Seeds were cultivated in certain pots. In this study, two factors were considered including: the concentrations of cadmium nitrate at four levels (0, 100, 200 and 300 ppm) which was considered as the first factor, the contamination as well as the lack of contamination with mycorrhiza fungi (Glomus Intraradices) which was considered as the second factor. The results showed that the presence of mycorrhiza fungi has increased the concentration of cadmium in all plant organs. It was also observed that increasing the concentration of cadmium in the soil has increased the cadmium concentrations in various organs of the sorghum plant. The mycorrhiza inoculation at all levels of the cadmium intake has significantly increased the cadmium concentration in different organs of the sorghum plant. According to this study, the presence of mycorrhiza fungi has increased the absorption of cadmium toxic elements. It also resulted in purification of the soil by sorghum

Health risk assessment of cadmium via dietary intake by adults in China

Cadmium in the human diet constitutes a potential chronic hazard to health. The objective of this study was to make a health risk assessment of dietary cadmium intake by adults in the 31 provinces (excluding Hong Kong, Taiwan and Macau) of China. The cadmium levels in a total of 2629 individual food samples ranged from not detected (below the limit of detection) to 17.32 mg kg⁻¹, with the highest concentration being found in an offal sample. The food group 'meat' showed the highest mean level of 0.129 mg kg⁻¹, while the lowest concentration of 8.0×10⁻⁴ mg kg⁻¹ was measured in the food group 'fruit'. The mean cadmium intakes, hazard quotients and annual excess lifetime cancer risks for national, northern and southern adult populations in China were 3.67 μg kg⁻¹ body weight (BW) week⁻¹, 0.52 and 4.56×10⁻⁵ a⁻¹, 2.63 μg kg⁻¹ BW week⁻¹, 0.38 and 3.27×10⁻⁵ a⁻¹ and 4.56 μg kg⁻¹ BW week⁻¹, 0.65 and 5.67×10⁻⁵ a⁻¹ respectively. The results of risk characterization for the national adult population were lower than safety risk levels of hazard quotient and annual excess lifetime cancer risk (5×10⁻⁵ a⁻¹). The mean annual excess lifetime cancer risk for the southern adult population was higher than the safety risk level. Therefore the carcinogenic risk for the southern population is of concern.

Dietary Cadmium Intake and the Risk of Cancer: A Meta-Analysis

BackgroundDiet is a major source of cadmium intake among the non-smoking general population. Recent studies have determined that cadmium exposure may produce adverse health effects at lower exposure levels than previously predicted. We conducted a meta-analysis to combine and analyze the results of previous studies that have investigated the association of dietary cadmium intake and cancer risk.MethodsWe searched PubMed, EMBASE, and MEDLINE database for case-control and cohort studies that assessed the association of dietary cadmium intake and cancer risk. We performed a meta-analysis using eight eligible studies to summarize the data and summary relative risks (RRs) and 95% confidence intervals (CIs) were calculated using a random effects model.ResultsOverall, dietary cadmium intake showed no statistically significant association with cancer risk (RR = 1.10; 95% CI: 0.99–1.22, for highest vs. lowest dietary cadmium group). However, there was strong evidence of heterogeneity, and subgroup analyses were conducted using the study design, geographical location, and cancer type. In subgroup analyses, the positive associations between dietary cadmium intake and cancer risk were observed among studies with Western populations (RR = 1.15; 95% CI: 1.08–1.23) and studies investigating some hormone-related cancers (prostate, breast, and endometrial cancers).ConclusionOur analysis found a positive association between dietary cadmium intake and cancer risk among studies conducted in Western countries, particularly with hormone-related cancers. Additional experimental and epidemiological studies are required to verify our findings.