Blood cadmium, lead, manganese, mercury, and selenium levels in American Indian populations: The Strong Heart Study.

BACKGROUND: Many American Indian (AI) communities are in areas affected by environmental contamination, such as toxic metals. However, studies assessing exposures in AI communities are limited. We measured blood metals in AI communities to assess historical exposure and identify participant characteristics associated with these levels in the Strong Heart Study (SHS) cohort. METHOD: Archived blood specimens collected from participants (n = 2014, all participants were 50 years of age and older) in Arizona, Oklahoma, and North and South Dakota during SHS Phase-III (1998-1999) were analyzed for cadmium, lead, manganese, mercury, and selenium using inductively coupled plasma triple quadrupole mass spectrometry. We conducted descriptive analyses for the entire cohort and stratified by selected subgroups, including selected demographics, health behaviors, income, waist circumference, and body mass index. Bivariate associations were conducted to examine associations between blood metal levels and selected socio-demographic and behavioral covariates. Finally, multivariate regression models were used to assess the best model fit that predicted blood metal levels. FINDINGS: All elements were detected in 100% of study participants, with the exception of mercury (detected in 73% of participants). The SHS population had higher levels of blood cadmium and manganese than the general U.S. population 50 years and older. The median blood mercury in the SHS cohort was at about 30% of the U.S. reference population, potentially due to low fish consumption. Participants in North Dakota and South Dakota had the highest blood cadmium, lead, manganese, and selenium, and the lowest total mercury levels, even after adjusting for covariates. In addition, each of the blood metals was associated with selected demographic, behavioral, income, and/or weight-related factors in multivariate models. These findings will help guide the tribes to develop education, outreach, and strategies to reduce harmful exposures and increase beneficial nutrient intake in these AI communities.

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.

Associations between socioeconomic status and blood cadmium levels in Korea.

OBJECTIVES: Although smoking is associated with both low socioeconomic status and blood cadmium (Cd) levels, the association between socioeconomic status and Cd levels remains unclear. Therefore, our study aimed to examine this association and to clarify whether smoking is a confounding or mediating variable in this relationship. METHODS: Data (n=7,734) were drawn from the Korea National Health and Nutrition Examination Survey (KNHANES, 2008- 2011), including years that contained data on blood Cd and urinary cotinine levels. We investigated the associations of income, education, and occupation with blood Cd levels. Smoking was investigated by categorizing participants by smoking status (never, former, and current) and pack-years into quartiles. The weekly frequency of rice and barley intake was analyzed to gain insights into participants' dietary patterns. Additionally, urinary cotinine levels were used to ensure the validity of the smoking variables. RESULTS: Participants earning a low income and with less formal education had higher blood Cd levels. After controlling for smoking, the association between income and Cd levels substantially weakened. Further controlling for education, the association between income and Cd levels disappeared. However, there was a strong negative association between education and Cd levels, even after controlling for smoking history, pack-years, and urinary cotinine levels. CONCLUSIONS: In cross-sectional data from the KNHANES, blood Cd levels were significantly higher among those with a low income and less formal education. Smoking history contributed to, but did not fully explain, these associations.

Assessment of 12 Metals and Metalloids in Blood of General Populations Living in Wuhan of China by ICP-MS.

Assessment of trace element levels in general population from the specific area is of importance for nutritional and occupational monitoring. In the current study, baseline blood levels of 12 toxic and/or essential metals and metalloids, including arsenic (As), cadmium (Cd), lead (Pb), mercury (Hg), chromium (Cr), thallium (Tl), manganese (Mn), copper (Cu), Zinc (Zn), calcium (Ca), iron (Fe), and magnesium (Mg), in general populations (n = 477) of Wuhan in central China were investigated by using inductively coupled plasma mass spectrometry (ICP-MS). The geometric means for As, Cd, Pb, Hg, Cr, Tl, Mn, and Cu were measured as 2.25, 0.70, 17.84, 1.90, 0.36, < 0.05, 12.40, and 783.76 µg/L, respectively. The geometric means for Zn, Ca, Fe, and Mg were 5.85, 56.66, 488.98, and 39.44 mg/L, respectively. We found the men had higher blood As, Pb, Hg, Zn, Fe, and Mg levels but had lower blood Cu and Ca levels than the women (p < 0.05). Age-related difference were found for blood Cu, Zn, Ca, Mg, Pb, Mn, As, Cd, and Hg levels (p < 0.05). Moreover, many metal concentrations were found correlated, with the strongest correlations between the pairs Fe-Mg (r = 0.57), Fe-Zn (r = 0.42), As-Hg (r = 0.46), Ca-Cu (r = 0.34), Pb-Hg (r = 0.36), Pb-Cd (r = 0.31), Pb-As (r = 0.25), and Ca-Fe (r = - 0.23). Compared with reports from other countries, most of our results were consistent, except that As Pb, Hg, Mn, and Cu showed different blood levels with European, Korea, or Beijing areas. Our study would be of importance for nutritional, environmental, and/or occupational monitoring of these metals in human.

Effects of lead, cadmium, arsenic, and mercury co-exposure on children's intelligence quotient in an industrialized area of southern China.

Exposure to metal(loid)s can lead to adverse effects on nervous system in children. However, little is known about the possible interaction effects of simultaneous exposure to multiple metal(loid)s on children's intelligence. In addition, relationship between blood lead concentrations (<100 µg/L) and the intelligence of children over 5 years needs further epidemiological evidence. We recruited 530 children aged 9-11 years, including 266 living in a town near an industrialized area and 264 from another town in the same city in South China as a reference. The levels of lead (Pb), cadmium (Cd), arsenic (As) and mercury (Hg) in blood (BPb, BCd, BAs, BHg) and urine (UPb, UCd, UAs, UHg) were assessed, as well as children's intelligence quotient (IQ). A significant decrease in IQ scores was identified in children from the industrialized town (p < .05), who had statistically higher geometric mean concentrations of BPb, BCd, UPb, UCd and UHg (65.89, 1.93, 4.04, 1.43 and 0.37 µg/L, respectively) compared with children from the reference town (37.21, 1.07, 2.14, 1.02 and 0.30 µg/L, respectively, p < .05). After adjusting confounders, only BPb had a significant negative association with IQ (B = -0.10, 95% confidence interval: -0.15 to -0.05, p < .001), which indicated that IQ decreased 0.10 points when BPb increased 1 µg/L. Significant negative interactions between BAs and BHg, positive interaction between UPb and UCd on IQ were observed (p < .10), and BPb <100 µg/L still negatively affected IQ (p < .05). Our findings suggest that although only BPb causes a decline in children's IQ when simultaneously exposed to these four metal(loid)s at relatively low levels, interactions between metal(loid)s on children's IQ should be paid special attention, and the reference standard in China of 100 µg/L BPb for children above 5 years old should be revised.

Cadmium chloride-induced testicular toxicity in male wistar rats; prophylactic effect of quercetin, and assessment of testicular recovery following cadmium chloride withdrawal.

This study assessed the effect of quercetin (QE) on cadmium chloride (CdCl2) - induced testicular toxicity, as well as the effect of withdrawal of CdCl2 treatment on same. Thirty male Wistar rats aged 10 weeks old and weighing 270-300g were assigned into 5 groups and used for this study. Rats in groups 1-4 were administered vehicle, CdCl2 (5mg/kg bwt), CdCl2+QE (5mg/kg bwt and 20mg/kg bwt, respectively) or QE (20mg/kg bwt) orally for 4 weeks. Group 5 rats received CdCl2, with 4 weeks recovery period. Results showed that cadmium accumulated in serum, testis and epididymis, decreased body weight, testicular and epididymal weights, sperm count, motility and viability. Cadmium decreased serum concentrations of reproductive hormones, but increased testicular glucose, lactate and lactate dehydrogenase activity. Cadmium decreased testicular enzymatic (superoxide dismutase, catalase and glutathione peroxidase) and non-enzymatic (glutathione, vitamins C and E) antioxidants, and increased malondialdehyde and hydrogen peroxide. Cadmium down-regulated Bcl-2 protein, up-regulated Bax protein, increased Bax/Bcl-2 ratio and cleaved caspase-3 activity. Histopathology of the testis showed decreased Johnsen's score and Leydig cell count. These negative effects were attenuated by QE administration, while withdrawal of CdCl2 did not appreciably reverse toxicity. We conclude that QE better protected the testis from CdCl2 toxicity than withdrawal of CdCl2 administration.

Prevalence and associated demographic characteristics of exposure to multiple metals and their species in human populations: The United States NHANES, 2007-2012.

Lead (Pb), cadmium (Cd), mercury (Hg), and arsenic (As) are among the top 10 pollutants of global health concern. Studies have shown that exposures to these metals produce severe adverse effects. However, the mechanisms underlying these effects, particularly joint toxicities, are poorly understood in humans. The objective of this investigation was to identify and characterize prevalent combinations of these metals and their species in the U.S. NHANES population to provide background data for future studies of potential metal interactions. Exposure was defined as urine or blood levels ≥ medians of the NHANES 2007-2012 participants ≥6 years (n = 7408). Adjusted-odds ratios (adj-OR) and 95% confidence intervals were determined for covariates (age, gender, and race/ethnicity, cotinine and body mass index). Species-specific analysis was also conducted for As and Hg including iAs (urinary arsenous acid and/or arsenic acid), met-iAs (urinary monomethylarsonic acid and/or dimethylarsinic acid), and oHg (blood methyl-mercury and/or ethyl-mercury). For combinations of As and Hg species, age- and gender-specific prevalence was determined among NHANES 2011-2012 participants (n = 2342). Data showed that approximately 49.3% of the population contained a combination of three or more metals. The most prevalent unique specific combinations were Pb/Cd/Hg/As, Pb/Cd/Hg, and Pb/Cd. Age was consistently associated with these combinations: adj-ORs ranged from 10.9 (Pb/Cd) to 11.2 (Pb/Cd/Hg/As). Race/ethnicity was significant for Pb/Cd/Hg/As. Among women of reproductive age, frequency of oHg/iAs/met-iAS and oHg/met-iAs was 22.9 and 40.3%, respectively. These findings may help prioritize efforts to assess joint toxicities and their impact on public health.

Arsenic, cadmium, lead and mercury levels in blood of Finnish adults and their relation to diet, lifestyle habits and sociodemographic variables.

The Northern Finland Birth Cohort program (NFBC) is the epidemiological and longitudinal prospective general population research program, which was established to promote health and wellbeing of the population in northern Finland. The aim of present study, as a part of the NFBC program, was to analyze the blood levels of arsenic (B-As), cadmium (B-Cd), lead (B-Pb), total mercury (B-Hg) and selenium (B-Se); to compare these levels with threshold limits; to study sociodemographic factors; and to correlate these levels with calcium and haemoglobin. The study was comprised of 249 NFBC subjects, of which 123 were female and 126 were male (ages 31.1 ± 0.3 and 31.1 ± 0.4, respectively). All participants were asked to complete a questionnaire regarding diet and living habits. The geometric means (± SD) of B-As were 0.49 ± 2.80 µg/l and 0.44 ± 2.72 µg/l; B-Cd were 0.18 ± 4.02 µg/l and 0.12 ± 3.21 µg/l; B-Pb were 17.0 ± 1.8 µg/l and 9.06 ± 2.20 µg/l; B-Hg were 2.18 ± 2.02 µg/l and 1.85 ± 1.78 µg/l; and B-Se were 106.0 ± 1.3 and 94.3 ± 1.3 µg/l in males and females, respectively. Among the subjects in the present analysis, 23 % of males and 17.1 % of females had B-As levels above the ATSDR normal human levels of B-As in unexposed individuals (1.0 µg/l). The B-Pb geometric mean (12.44 µg/l) was approximately one eighth the CDC toxicological cut-off point of 100 µg/l. Twenty-one individuals (8.4 %) exceeded a B-Hg level of 5.8 µg/l. Fifty-eight females (47 %) had a B-Hg higher than 2.0 µg/l, the German Federal Environmental Agency cut-off point for women (18-69 years) who consume fish at least three times/month; therefore, their babies could be at risk of adverse effects during development.

Maternal Stress and Depressive Symptoms and Infant Development at Six Months: the Mothers and Children's Environmental Health (MOCEH) Prospective Study.

Our objective is to evaluate the relationships between prenatal maternal stress and depressive symptoms, respectively, and infant neurodevelopment at 6 months, adjusted for heavy metals and oxidative stress. This research is a part of a multi-center birth cohort study in South Korea. Information on stress and depressive symptoms was collected during the first trimester using Psychosocial Well-Being Index Short Form (PWI-SF) and Center for Epidemiological Studies Depression Scale (CES-D). The Korean Bayley Scales of Infant Development-II assessment (BSID-II), which includes the standardized mental development index (MDI) and psychomotor developmental index (PDI), and Korean Ages & Stages Questionnaires (K-ASQ) were applied to infants at six months of age. A higher index score indicates better development. Among 641 babies, 320 were female (50%). Maternal PWI ≥ 29 (vs. PWI ≤ 18) during early pregnancy was associated with a decrease in MDI scores of 5.37 points (P = 0.02) after adjusting for socioeconomic factors. Maternal CES-D ≥ 26 (vs. CES-D ≤ 10) during early pregnancy was associated with a decrease in MDI scores of 8.18 points (P = 0.01). The associations remained significant even after adjustment for lead, cadmium, and MDA levels (P < 0.05). However, no association was found between maternal PWI/CES-D and PDI score. No interaction was observed between stress and lead exposure. We found an inverse association between prenatal maternal stress and depressive symptoms, and MDI scores in 6-month-old infants after adjustment for prenatal lead exposure, which is known to affect cognitive function negatively.

Predictors of cadmium and lead concentrations in the blood of residents from the metropolitan area of Athens (Greece).

The Cd and Pb blood contents of healthy adult subjects who are non-occupationally exposed and living in the metropolitan area of Athens (Greece) have not been assessed thus far. Additionally, Greeks rank first among EU27 in terms of smoking habits. To fill the existing gap, we aimed to evaluate the predictors and propose reference values (RVs) of the Cd (CdB) and Pb (PbB) blood concentrations in residents of the metropolitan area of Athens (Greece). Age, sex, smoking, alcohol drinking, educational status and nutritional habits were used as variables, with an emphasis on smoking. CdB and PbB determinations were performed directly by graphite furnace atomic absorption spectrometry (GFAAS) following the appropriate dilution of the samples with Triton-X-100. The RVs of CdB and PbB proposed for the general adult population of the Metropolitan area of Athens, Greece (upper limit of the 95% CI of the 95th percentile of the distribution of values), were 2.3 and 88µgL(-1) (P95: 1.8 and 77µgL(-1); 95% CI (P95): 1.5-2.3 and 70-88µgL(-1)), respectively. Males had a higher median CdB (0.69µgL(-1)) than females (0.55µgL(-1)). Subjects aged <40years had a lower median CdB (0.51µgL(-1)) than the elderly (≥60years; 0.60µgL(-1)). The CdB in smokers (1.2µgL(-1)) was almost threefold higher than in non-smokers (0.46µgL(-1)). The PbB levels were higher in males (31µgL(-1)) than females (20µgL(-1)). Subjects aged <40years had a lower median PbB (17µgL(-1)) than the elderly (≥60years; 32µgL(-1)). A multiple linear regression analysis demonstrated that the predictor variables for the CdB levels were the standardized beta weight, smoking, age, alcohol consumption, and intake of leafy vegetables, whereas for the PbB levels they were sex and age.

Assessment of the Cadmium Exposure in the Blood, Diet, and Water of the Pumi People in Yunnan, China.

Cadmium (Cd) is considered as one of the most toxic and carcinogenic heavy metals. Accumulation of Cd in the human body can cause multiorgan dysfunction. Long-term irrational mining activities have led to serious Cd pollution in soil, water, and even agricultural products. Therefore, evaluating the Cd exposure levels of people living in mining areas is of great importance. In the current study, we chose the Pumi people who lived in Jinding and Tongdian towns of Lanping county in Yunnan province, China, to do the on-site nutritional epidemiology investigation and laboratory detection. We analyzed the content of the Cd in peripheral blood and mixed dietary, as well as water samples in the Pumi residents of the two towns. Results showed that the blood Cd levels of people in Jinding town, which is nearer the mining district, were statistically significantly higher than those in Tongdian town. The P 50 of blood Cd level of the two towns was 0.64 ng/mL. In addition, the P 50 of the mixed diet of the two towns was 8.32 µg/kg. There was a weak correlation between blood Cd levels and Cd exposure in the mixed diet, PTDI, and PTWI of the Pumi people. In addition, higher concentrations of Cd were observed in the water of Jinding town, indicating people in Jinding town risking more Cd exposure. These results indicated that diet and water are critical factors of Cd exposure for the residents and the nearer people living to mining district risking the more Cd exposure.

Attention-deficit/hyperactivity symptoms in preschool children from an e-waste recycling town: assessment by the parent report derived from DSM-IV.

BACKGROUND: To investigate the attention-deficit/hyperactivity disorder (ADHD) status among preschool-aged children in Guiyu, an electronic waste (e-waste) recycling town in Guangdong, China. METHODS: Two hundred and forty-three parents were surveyed regarding ADHD behaviors in their children (aged 3-7 years) based solely on the DSM-IV criteria. The peripheral blood samples were taken from these children to measure blood lead levels (BLLs) and blood cadmium levels (BCLs). RESULTS: 12.8% of children met the criteria for ADHD, of which the inattentive, hyperactive/impulsive and combined subtypes were 4.5%, 5.3% and 2.9% respectively. Of all children, 28.0% had BLLs ≥ 10 ug/dL and only 1.2% had BCLs ≥ 2 ug/L, levels conventionally considered high. Either modeled by univariate or multivariable analysis, the three ADHD scores (inattentive, hyperactive/impulsive and total scores) calculated from the Parent Rating Scale showed strong positive correlations with BLLs but not with BCLs. Furthermore, children with high BLLs had 2.4 times higher risk of ADHD than those with low BLLs (OR: 2.4 [95% CI: 1.1-5.2]). When each of the 18 categories on the Parent Rating Scale was separately analyzed, children with high BLLs had significant higher risks for positive ADHD symptoms than those with low BLLs in 12 of the 18 categories (ORs ranged from 2.1 [95% CI: 1.1-3.9] to 3.6 [95% CI: 1.7-7.5]). CONCLUSIONS: This study suggests that environmental lead contamination due to e-waste recycling has an impact on neurobehavioral development of preschool children in Guiyu.

Human exposure and risk assessment of cadmium for residents of abandoned metal mine areas in Korea.

The objective of this study is to find the Cd levels in agricultural crops compared to soil, to evaluate the relationship between daily intake dose through the multimedia/multi-pathway of human exposure and biomarker levels of the residents in mine vicinity area. We collected and cited the data of four out of ten health impact assessments for the residents of abandoned mine areas undertaken by the Korea Ministry of Environment in 2008. The Cd levels in soil were significantly decreased by the separation distance from the mines. The Cd levels in blood were significantly different between residents in mine areas and in comparative areas, but urinary Cd levels did not differ. The Cd levels in blood were related to the age; the separation distance from mine to residence; the daily intake dose via ingestion of drinking water, crops, and surface soil; and inhalation of ambient air of Cd, but urinary Cd levels were not relevant with various sociodemographic characteristics and exposure factors. The average hazard quotient (HQ) value of Cd in the mining site was below 1.0, but the maximum HQ was closed to 1.0. The results indicated that the ingestion of Cd-contaminated soil and agricultural crops by local inhabitants could pose potential adverse health effects to long-term residents consuming rice grown near to the mining areas.

Co-exposure of arsenic and cadmium through drinking water and tobacco smoking: risk assessment on kidney dysfunction.

The combined exposure of arsenic (As) and cadmium (Cd) causes more pronounced renal toxicity. The study aimed to evaluate the level of As and Cd in biological samples (blood and urine) of adults males, age ranged (30-50 years) exposed referent (ER) and exposed kidney patients (EKP), consumed contaminated drinking water of lake and smoking local cigarettes manufactured by tobacco plants grown on agricultural soil, irrigated with contaminated lake water. For comparative purpose age matched nonexoposed referent (NR) and nonexposed kidney patient (NKP), consumed municipal treaded water and smoking branded cigarette were also selected. The As and Cd levels in drinking water, biological samples, tobacco of branded and nonbranded cigarettes were analyzed using electrothermal atomic absorption spectrometry. The As and Cd concentrations in lake water were higher than the permissible limit recommended by the World Health Organization for drinking water. The As and Cd levels in local cigarette tobacco were found to be 3- to 4-folds higher than branded cigarettes. The biochemical parameters especially urinary N-acetyl-ß-glucosaminidase (NAG) of ER, EKP, ER, and EKP subjects were studied as a biomarkers of renal dysfunction. The NAG values were found to be higher in EKP as compared to NKP (p < 0.01). The linear regressions showed higher correlations between As and Cd concentrations in water versus blood and urine samples of EKP (r = 0.71-0.78 and 0.68-0.72), as compared to NKP (p < 0.05).

Associations of cadmium and lead exposure with leukocyte telomere length: findings from National Health and Nutrition Examination Survey, 1999-2002.

Cadmium and lead are ubiquitous environmental contaminants that might increase risks of cardiovascular disease and other aging-related diseases, but their relationships with leukocyte telomere length (LTL), a marker of cellular aging, are poorly understood. In experimental studies, they have been shown to induce telomere shortening, but no epidemiologic study to date has examined their associations with LTL in the general population. We examined associations of blood lead and cadmium (n = 6,796) and urine cadmium (n = 2,093) levels with LTL among a nationally representative sample of US adults from the National Health and Nutrition Examination Survey (1999-2002). The study population geometric mean concentrations were 1.67 µg/dL (95% confidence interval (CI): 1.63, 1.70) for blood lead, 0.44 µg/L (95% CI: 0.42, 0.47) for blood cadmium, and 0.28 µg/L (95% CI: 0.27, 0.30) for urine cadmium. After adjustment for potential confounders, the highest (versus lowest) quartiles of blood and urine cadmium were associated with -5.54% (95% CI: -8.70, -2.37) and -4.50% (95% CI: -8.79, -0.20) shorter LTLs, respectively, with evidence of dose-response relationship (P for trend < 0.05). There was no association between blood lead concentration and LTL. These findings provide further evidence of physiological impacts of cadmium at environmental levels and might provide insight into biological pathways underlying cadmium toxicity and chronic disease risks.

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.

Risk assessment for Thai population: benchmark dose of urinary and blood cadmium levels for renal effects by hybrid approach of inhabitants living in polluted and non-polluted areas in Thailand.

BACKGROUND: The aim of the present study was to estimate the benchmark doses (BMD) for renal effects for health risk assessment of residents living in Cd-polluted and non-polluted areas in a Thai population. METHODS: The study participants consisted of inhabitants aged 40 years or older who lived in a non-polluted area (40 men and 41 women) and in the environmentally polluted Mae Sot District (230 men and 370 women) located in northwestern Thailand. We measured urinary and blood cadmium (Cd) as markers of long-term exposure and urinary ß2-microglobulin (ß2-MG) and N-acetyl-ß-D-glucosaminidase (NAG) as renal tubular effect markers. An updated hybrid approach was applied to estimate the benchmark doses (BMD) and their 95% lower confidence limits (BMDL) of urinary and blood Cd for Cd-induced renal effects in these subjects. BMD and BMDL corresponding to an additional risk (BMR) of 5% were calculated with the background risk at zero exposure set to 5% after adjusting for age and smoking status. RESULTS: The estimated BMDLs of urinary Cd for renal effect markers were 6.9 for urinary ß2-MG and 4.4 for NAG in men and 8.1 for ß2-MG and 6.1 for NAG µg/g creatinine (Creat) in women. These BMDLs of urinary Cd (µg/g Creat) for NAG were less than the geometric mean urinary Cd in the polluted area (6.5 in men and 7.1 in women). The estimated BMDLs of blood Cd (µg/L) were 6.2 for urinary ß2-MG and 5.0 for NAG in men and 5.9 for ß2-MG and 5.8 for NAG in women. The calculated BMDLs were similar or less compared with the geometric mean blood Cd (µg/L) in the polluted Thai area (6.9 in men and 5.2 in women). CONCLUSION: The BMDLs of urinary and blood Cd for renal effects were estimated to be 4.4-8.1 µg/g Creat and 4.4-6.2 µg/L in the Thai population aged ≥ 40 years old, suggesting that more than 40% of the residents were at risk of adverse renal effects induced by Cd exposure in Thailand.

Australia's leading public health body delays action on the revision of the public health goal for blood lead exposures.

Globally, childhood blood lead levels have fallen precipitously in developed countries since the 1970s following action by international bodies such as the WHO and Food and Agricultural Organization (FAO) of the United Nations. These reductions have been affected by the activities of national agencies such as the US EPA and US Centers for Disease Control and Prevention in the establishment of air lead and blood lead standards, the introduction of legislation to remove lead from petrol, paint and consumer products and tighter restrictions on lead emissions. The outcome of recent major international reviews of research into the effects of low-level lead exposures (e.g. by WHO, USA health and environmental agencies, German and Canadian health bodies) has resulted in recommendations to reduce and eliminate lead exposures. By contrast, Australian policy responses to the incontrovertible evidence that adverse neurocognitive and behavioural effects that occur at levels well below the current national goal of 10µg/dL have stalled. The delayed response by Australia occurs at a time when blood lead levels in two of Australia's three primary lead mining and smelting cities: Port Pirie, South Australia and Broken Hill, New South Wales, are rising. In the third city, Mount Isa, Queensland, there is still no systematic, annual testing of childhood blood lead values. This is despite the fact that Mount Isa has the highest lead (and other toxic metals such as cadmium and arsenic) emissions to the environment (120tonnes of lead in 2011/12) from any single point source in Australia. It is clear that both state and national policy approaches to the ongoing risks of lead exposure need to be revised urgently and in line with contemporary international standards. Recommended changes should include a new lower blood lead intervention level of no more than 5µg/dL, with a national goal for all children under 5years of age to have a blood lead level of below 1µg/dL by 2020. In order to achieve any new lower exposure goals other relevant lead standards including air, dust, soil and water must also be revised downwards.

Serum cadmium levels in a sample of blood donors in the Western Amazon, Brazil, 2010-2011.

A cross-sectional study was conducted to determine the distribution of serum cadmium (Cd) levels in blood donors in Rio Branco, Acre State, Brazil. Blood samples were obtained from 922 volunteer blood donors from 18 to 65 years of age at the Hemoacre blood center in 2010-2011. Mean serum Cd was 0.37µg/L (95%CI: 0.33-0.41). Increased serum Cd was associated with lower schooling; individuals with less than five years of schooling showed a mean Cd of 0.61µg/L (95%CI: 0.34-0.89), compared to 0.34µg/L (95%CI: 0.28-0.40) among those with more than nine years of schooling. Mean serum Cd was three times higher among smokers. Smoking showed a positive association with Cd level, with an OR of 12.36 (95%CI: 7.70-19.84). Meanwhile, serum Cd was lower among individuals that regularly drank tea, as compared to non-tea drinkers. Serum Cd levels were mostly below the reference value (88.3% of participants). Mean serum Cd in the current study indicates that in general the population studied here is not exposed to worrisome Cd levels.

Serum cadmium levels in a sample of blood donors in the Western Amazon, Brazil, 2010-2011 / Niveis sericos de cadmio em uma amostra de doadores de sangue na Amazonia Ocidental, Brasil, 2010-2011 / Niveles sericos de cadmio en una muestra de donantes de sangre en la Amazonia occidental, Brasil, 2010-2011

A cross-sectional study was conducted to determine the distribution of serum cadmium (Cd) levels in blood donors in Rio Branco, Acre State, Brazil. Blood samples were obtained from 922 volunteer blood donors from 18 to 65 years of age at the Hemoacre blood center in 2010-2011. Mean serum Cd was 0.37µg/L (95%CI: 0.33-0.41). Increased serum Cd was associated with lower schooling; individuals with less than five years of schooling showed a mean Cd of 0.61µg/L (95%CI: 0.34-0.89), compared to 0.34µg/L (95%CI: 0.28-0.40) among those with more than nine years of schooling. Mean serum Cd was three times higher among smokers. Smoking showed a positive association with Cd level, with an OR of 12.36 (95%CI: 7.70-19.84). Meanwhile, serum Cd was lower among individuals that regularly drank tea, as compared to non-tea drinkers. Serum Cd levels were mostly below the reference value (88.3% of participants). Mean serum Cd in the current study indicates that in general the population studied here is not exposed to worrisome Cd levels.

Objetivou-se, por meio de estudo transversal, determinar a distribuição dos níveis séricos de cádmio (Cd) em doadores de sangue em Rio Branco, Acre, Brasil. O sangue foi obtido de 922 doadores voluntários entre 18 e 65 anos no Hemoacre, entre 2010-2011. A média da concentração de Cd foi de 0,37µg/L (IC95%: 0,33-0,41). Houve tendência de aumento com a diminuição do nível de escolaridade; indivíduos com menos de cinco anos de estudo apresentaram média de 0,61µg/L (IC95%: 0,34-0,89), enquanto aqueles com mais de nove anos de estudo obtiveram média de 0,34µg/L (IC95%: 0,28-0,40). A média da concentração de Cd apresentou-se três vezes maior entre os fumantes. O tabagismo demonstrou associação positiva com OR 12,36 (IC95%: 7,70-19,84). Já a concentração de Cd entre os indivíduos com hábitos de tomar chás apresenta- se menor quando comparada àqueles que não utilizam. Os níveis séricos de Cd foram, em sua maioria, abaixo do valor de referência (88,3% dos participantes). As médias encontradas no presente estudo indicam que, no geral, a população estudada não está exposta a níveis preocupantes de exposição ao Cd.

El objetivo de utilizar un estudio transversal para determinar la distribución de los niveles séricos de Cd en los donantes de Río Branco no expuestos al metal. Se obtuvo sangre de 922 voluntarios de entre 18 y 65 años en Hemoacre entre 2010-2011. La concentración media de Cd fue 0,37µg/L (IC95%: 0,33-0,41). Hubo una tendencia de aumento según el nivel educativo: las personas con menos de cinco años de estudio tenían una media de 0,61µg/l (IC95%: 0,34-0,89), mientras que quienes contaban con más de nueve años de escolaridad poseían un promedio 0,34µg/L (IC95%: 0,28-0,40). La concentración promedio de Cd se presentó tres veces mayor entre los fumadores. El consumo de cigarrillos mostró una asociación positiva con OR 12,36 (IC95%: 7,70-19,84). Ya la concentración de Cd en las personas con hábitos de tomar té era más pequeña en comparación con aquellos que no lo toman. Los niveles séricos de Cd fueron en su mayoría por debajo del valor de referencia (88,3% de los participantes). Los medios encontrados en este estudio indican que, en general, la población no está expuesta a niveles preocupantes de Cd.