Graphite Furnace Atomic Absorption Spectrophotometry Research Articles

B-277 Detectable Levels of Toxic Metals in Children's Playgrounds

Abstract Background Metal-contaminated soil poses significant health risks to kids because they are more sensitive to heavy metal exposure in the environment. Studies have shown that continuous exposure to metals can increase the risk of metal accumulation in blood and various body organs. This study determines the levels of some toxic metals in various playgrounds in our community. Methods We determined the levels of lead (Pb), chromium (Cr), cadmium (Cd), and copper (Cu) in six playgrounds (parks) (T-RP, T-GP, T-TX, L-HH, L-WH, L-SPLX) using graphite furnace atomic absorption spectrophotometry (GF-AAS) technique. Soil samples were collected at least one foot below the soil surface, and metal was extracted using ultra-pure nitric before analysis using GF-AAS. Data were analyzed using analysis of variance (ANOVA). Results The results showed significant detectable levels of the metals in all playgrounds evaluated in this study. L-WH Park in League City has the highest detectable levels of Pb (12.43 ± 46 mg/Kg, P<0.05) compared to other children playgrounds examined in this study (T-RP (3.93 ± 3.97 mg/Kg), T-GP (7.09 ± 2.79 mg/Kg), T-TX (6.05 ± 1.92 mg/Kg), L-HH (4.68 ± 0.76 mg/Kg), L-SPLX (2.64 ± 1.63 mg/Kg). The concentration of detectable cadmium in T-RP park (0.16 ± 0.11 mg/Kg) was significantly higher than all the other five children's playgrounds studied L-WH (0.02 ± 0.01 ), T-GP (0.05 ± 0.04 mg/Kg), T-TX (0.02 ± 0.01 mg/Kg), L-HH (0.04 ± 0.01 mg/Kg), L-SPLX (0.09 ± 0.04 mg/Kg) (P<0.05). Conclusions The playgrounds contain detectable toxic metals that might pose health risks to children in the community. Though the lead levels are below the CDC-recommended lead soil concentration in urban areas, they still pose health risks to children in the environment when continuously exposed to the playground. The concentrations of Cu and Cr were not statistically different among the playgrounds. The detection of Pb and Cd highlights the potential health risks to children. Overall, this study shows that metal levels in playgrounds should be public information available to parents.

Arsenic exposure and measures of glucose tolerance in Bangladeshi adults: A cross-sectional study.

Arsenic has been associated with diabetes and impaired glucose tolerance in many studies, although some reports have shown null findings. We conducted a cross-sectional study among 300 adults in Bangladesh. Participants were randomly selected from a roster of 1800 people who previously participated in studies of arsenic and skin lesions. We measured fasting glucose and insulin levels. We assessed drinking water arsenic concentration using graphite furnace atomic absorption spectrophotometry (GF-AAS) and toenail arsenic concentration using inductively coupled mass spectrometry (ICP-MS). We ran covariant-adjusted, linear regression and spline models to examine associations of arsenic concentrations with the homeostatic model assessment of insulin resistance (HOMA-IR), a marker of insulin resistance, and HOMA of beta-cell function (HOMA-β), a marker of beta-cell function. Among 285 participants with complete data, the median (IQR) arsenic concentration was 4.0 (6.9) μg/g in toenails and 39.0 (188.5) μg/L in drinking water. Arsenic concentrations were not associated with insulin resistance or beta-cell function. HOMA-IR was 0.67% lower and HOMA-β was 0.28% lower per µg/g increment in toenail arsenic, but these effect estimates were small, and confidence intervals crossed the null value. Although arsenic exposure has been associated with diabetes, we found no evidence of an adverse effect on insulin resistance or beta-cell function.

The Assessment of Selenium, Aluminum, and Zinc in Children with Autism Spectrum Disorder.

ASD is a complex condition defined by many causes, one of them being excessive concentrations of necessary and harmful chemicals in children. The serum, hair, and nails of children with ASD have lower levels of critical trace elements, according to studies. It is quite obvious that bio elements are involved in physiology and pathophysiology. Thus, this study examined trace element contents in serum samples from children with autism spectrum disorder (ASD), specifically zinc (Zn), aluminum (Al), and selenium (Se). The study also looked for links between trace element levels and autistic severity. The study included 47 children with autism spectrum disorder, and the Gilliam's Scale was used for severity. The study also included 53 healthy kids with age and gender-matched with those of ASD. For serum trace element analysis, graphite furnace atomic absorption spectrophotometry was used. The study found significant decreases in selenium and zinc concentration (OR, 5.25; CI, 1.96 ~ 14.08; p < 0.001) and increases in aluminum level (OR, 39.34; CI, 8.20 ~ 89.45; p < 0.001) in children with ASD compared to the control group. The area under the curve (AUC) values of 0.85 for Se, 0.98 for Al, and 0.7 for Zn showed high sensitivity and specificity for all parameters. Results indicate a strong positive connection between ASD and their levels of selenium (Se) and zinc (Zn) (β, 0.48; CI, 0.280 ~ 0.679; p < 0.001 and β, 0.31; CI, 0.10 ~ 0.52; p = 0.005). There is a negative correlation between ASD and aluminum (Al) (β 0.83; CI, 0.71 ~ 0.95; p < 0.001). This element may be a biomarker for autism in youngsters. High odds ratio (OR) values indicate trace element risk in autistic children.

Quantifying heavy metal and radionuclide contamination in fish and water proximal to a uranium tailings facility: A Linshui River basin investigation, China

BackgroundThe objective of this study is to evaluate the concentrations of heavy metals and radionuclides in water and fish samples collected from six designated sampling stations along the Linshui River, in close proximity to a Uranium Tailing Pond situated in China. Additionally, it seeks to estimate the bioaccumulation of heavy metals and conduct risk assessments, both carcinogenic and non-carcinogenic, for consumers. MethodsWater and fish samples (yellowhead catfish and common carp) were systematically collected from six stations along the river from January to June 2023, adhering to ethical standards and standard protocols for assessing water quality. Samples underwent chemical preparation and analysis for heavy metals using Graphite Furnace Atomic Absorption Spectrophotometry and Cold Vapor Atomic Absorption Spectroscopy, and for radionuclides using gamma spectrometry, with all methods validated for accuracy. ResultsThe water samples showed metal and radionuclide concentrations within acceptable limits, except for higher levels of U and Th compared to background values. Heavy metal concentrations were higher in common carp compared to yellowhead catfish, with both species exhibiting a similar trend. While non-carcinogenic health risk, as indicated by target hazard quotients, was low for consumers, the health risk data emphasized the carcinogenic threats posed by U238 and Th234. ConclusionsThe study highlights the importance of implementing comprehensive river restoration measures. Additionally, the bioconcentration factor values indicate minimal accumulation of heavy metals in the muscle tissue of fish.

Arsenic modifies the effect of folic acid in spina bifida prevention, a large hospital-based case-control study in Bangladesh

BackgroundSpina bifida, a developmental malformation of the spinal cord, is associated with high rates of mortality and disability. Although folic acid-based preventive strategies have been successful in reducing rates of spina bifida, some areas continue to be at higher risk because of chemical exposures. Bangladesh has high arsenic exposures through contaminated drinking water and high rates of spina bifida. This study examines the relationships between mother’s arsenic exposure, folic acid, and spina bifida risk in Bangladesh.MethodsWe conducted a hospital-based case-control study at the National Institute of Neurosciences & Hospital (NINS&H) in Dhaka, Bangladesh, between December 2016 and December 2022. Cases were infants under age one year with spina bifida and further classified by a neurosurgeon and imaging. Controls were drawn from children seen at NINS&H and nearby Dhaka Shishu Hospital. Mothers reported folic acid use during pregnancy, and we assessed folate status with serum assays. Arsenic exposure was estimated in drinking water using graphite furnace atomic absorption spectrophotometry (GF-AAS) and in toenails using inductively coupled plasma mass spectrometry (ICP-MS). We used logistic regression to examine the associations between arsenic and spina bifida. We used stratified models to examine the associations between folic acid and spina bifida at different levels of arsenic exposure.ResultsWe evaluated data from 294 cases of spina bifida and 163 controls. We did not find a main effect of mother’s arsenic exposure on spina bifida risk. However, in stratified analyses, folic acid use was associated with lower odds of spina bifida (adjusted odds ratio [OR]: 0.50, 95% confidence interval [CI]: 0.25-1.00, p = 0.05) among women with toenail arsenic concentrations below the median value of 0.46 µg/g, and no association was seen among mothers with toenail arsenic concentrations higher than 0.46 µg/g (adjusted OR: 1.09, 95% CI: 0.52–2.29, p = 0.82).ConclusionsMother’s arsenic exposure modified the protective association of folic acid with spina bifida. Increased surveillance and additional preventive strategies, such as folic acid fortification and reduction of arsenic, are needed in areas of high arsenic exposure.

A Cross-Sectional Analysis Investigating Pregnant Women's Renal Function and Its Association with Lead and Cadmium Exposures-The DSAN Birth Cohort Study in Recôncavo Baiano, Brazil.

Kidney dysfunction is increasing worldwide and is exacerbated by exposure to toxic metals. Also, pregnancy poses an overload on kidney function. We investigated how blood lead (PbB) and cadmium (CdB) levels were associated with kidney function in pregnant women from Recôncavo Baiano, Brazil, during their second trimester. In this cross-sectional study, the estimated glomerular filtration rate (eGFR) was calculated from serum creatinine and whole blood metal levels were measured by graphite furnace atomic absorption spectrophotometry in 136 volunteers. Sociodemographic data were collected using semi-structured questionnaires. The medians (IQR) of PbB, CdB, and eGFR were 0.85 µg/dL (0.45-1.75), 0.55 µg/L (0.08-0.91), and 121.8 mL/min/1.73 m2 (106.0-127.9), respectively. PbB medians were significantly higher in the eGFR < 90 group at 2.00 µg/dL (0.83, 3.10). After age-adjusted logistic regression, pregnant women with elevated PbB levels had decreased eGFR (OR = 1.82; 95%-CI, 1.14-3.14). However, the participants with elevated PbB levels who reported consuming alcohol during pregnancy or had CdB in the highest tertile had higher odds of reduced eGFR (OR = 2.44; 95%-CI, 1.30-5.47) and (OR = 11.22; 95% CI, 2.53-103.51), respectively. These results suggest that low Pb exposure may affect kidney function in pregnant women and calls for further investigation into toxic metal co-exposures on kidney function during pregnancy in at-risk communities.

Association between Blood Lead Levels and Silent Myocardial Infarction in the General Population.

Background: Although the link between lead exposure and patterns of cardiovascular disease (CVD) has been reported, its association with silent myocardial infarction (SMI) remains unexplored. We aimed to assess the association between blood lead levels (BLLs) and SMI risk. Methods: We included 7283 (mean age 56.1 ± 2.52 years, 52.5% women) participants free of CVD from the Third National Health and Nutrition Examination Survey. BLL was measured using graphite-furnace atomic absorption spectrophotometry. SMI was defined as ECG evidence of myocardial infarction (MI) without history of MI. The association between SMI and BLLs was examined using multivariable logistic regression. Results: SMI was detected in 120 participants with an unweighted prevalence of 1.65%. Higher BLL correlated with higher SMI prevalence across BLL tertiles. In multivariable-adjusted models, participants in the third BLL tertile had more than double the odds of SMI (OR: 3.42, 95%CI: 1.76-6.63) compared to the first tertile. Each 1 µg/dL increase in BLL was linked to a 9% increase in SMI risk. This association was consistent across age, sex, and race subgroups. Conclusions: Higher BLLs are associated with higher odds of SMI in the general population. These results underscore the significance of the ongoing efforts to mitigate lead exposure and implement screening strategies for SMI in high-risk populations.

Abstract 11969: Association Between Blood Lead Levels and Silent Myocardial Infarction in the General Population

Background: While the connection between environmental lead exposure and cardiovascular disease (CVD) is well-known, the association with silent myocardial infarction (SMI) remains unexplored. Aims: Our objective was to examine if there is a connection between higher blood lead levels (BLL) and increased prevalence of SMI in the general population. Methods: This analysis included 7,283 (mean age 56.1±2.52 years, 52.5% women, 49.8% Whites) participants from the Third National Health and Nutrition Examination Survey who were free of CVD. Graphite furnace atomic absorption spectrophotometry was used to measure blood lead levels (BLL). SMI was defined as the presence of electrocardiographic evidence of myocardial infarction (MI) without a prior history of MI. Multivariable logistic regression analysis was used to examine the cross-sectional association between baseline BLL and SMI. Results: Participants with higher levels of BLL had a higher prevalence of SMI (SMI prevalence 0.4%, 0.9% and 2.4% across BLL tertiles). In a multivariable-adjusted model, the highest BLL tertile was associated with over three times the odds of SMI compared to the first tertile, with an odds ratio of 3.42 (95% CI: 1.76-6.63). There was a 9% increase in the odds of SMI for every 1 μg/dL increase in BLL (Table). This association was consistent across subgroups stratified by median age, sex, and race. Conclusion: Higher BLL levels are associated with a higher likelihood of SMI in the general US population. These results underscore the ongoing need for efforts to minimize lead exposure among the general public.

Health compromising components in French fries and fried chicken available in the markets of Dhaka city, Bangladesh

ABSTRACT French fries (FF) and fried chicken (FC) are known contributors to overweight and obesity among adolescents worldwide. Top selling five brands for both FF and FC were analyzed to determine their health compromising contents, which were sampled from the markets of Dhaka, Bangladesh. Sodium (Na) was determined by flame photometry, trans fatty acids (TFAs) by gas chromatography and heavy metals like arsenic (As), lead (Pb), cadmium and chromium by graphite furnace atomic absorption spectrophotometry. The median concentration of Na, TFA, As and Pb in FF was 0.45 gm/100 gm, 0.11 gm/100 gm, 0.93 mg/kg and 0.03 mg/kg, respectively. Similarly, in FC the median concentration of Na, TFA, As and Pb was 0.46 gm/100 gm, 0.13 gm/100 gm, 0.053 mg/kg and 0.06 mg/kg, respectively. The study findings suggests that consuming FF and FC impose a health risk among the exposed population.

Maternal Exposure to Potentially Toxic Metals and Birth Weight: Preliminary Results from the DSAN-12M Birth Cohort in the Recôncavo Baiano, Brazil.

Prenatal exposure to potentially toxic metals (PTM) may impair fetal growth (FG). We investigated the relationship between maternal exposure to lead (Pb), cadmium (Cd) and manganese (Mn) and birth weight (BW) of 74 newborns. Blood was collected during the second trimester of pregnancy to determine Pb (PbB) and Cd (CdB), while hair (MnH) and toenails (MnTn) were used for Mn. Samples were analyzed by graphite furnace atomic absorption spectrophotometry (GFAAS). Sociodemographic and BW data were collected from questionnaires and maternity records, respectively. The medians (P25th-P75th) of PbB, CdB, MnH, and MnTn were, respectively, 0.9 (0.5-1.8) µg/dL; 0.54 (0.1-0.8) µg/L; 0.18 (0.1-0.4) µg/g; and 0.65 (0.37-1.22) µg/g. The means (standard deviation) of birth weight according to sex were 3067 (426.3) and 3442 (431) grams, respectively, for girls and boys. MnTn presented an inverse correlation with the BW/gestational age ratio for girls (rho = -0.478; p = 0.018), suggesting the effect of sex modification. Although BW correlation with CdB was not statistically significant, hierarchical linear regression (beta = -2.08; 95% CI-4.58 to 0.41) suggested a fetotoxic effect. These results confirmed the threat PTMs may represent and the need for more extensive research to elucidate their role in inadequate FG in developing countries.

Variation in the burden and chemical forms of thallium in non-detoxified tissues of tilapia fish (Oreochromis niloticus) from waterborne exposure

Thallium (Tl) is highly toxic to aquatic ecosystems, but information about its concentration and distribution characteristics in different fish tissues is limited. In this study, juvenile tilapia (Oreochromis niloticus) were exposed to Tl solutions with different sub-lethal concentrations for 28 days, and the Tl concentrations and distribution patterns in the fish non-detoxified tissues (gills, muscle, and bone) were analyzed. The Tl chemical form fractions, Tl-ethanol, Tl–HCl, and Tl-residual, corresponding to easy, moderate, and difficult migration fraction, respectively, in the fish tissues were obtained by sequential extractant approach. The Tl concentrations of different fractions and total burden were determined using graphite furnace atomic absorption spectrophotometry. Exposure-concentration effect determined the Tl burden in the fish tissues. The average Tl-total concentration factors were 360, 447, and 593 in the bone, gills, and muscle, respectively, and the limited variation during the exposure period indicates that tilapia have a strong ability to self-regulate and achieve Tl homeostasis. However, Tl fractions varied in tissues, and the Tl–HCl fraction dominated in the gills (60.1%) and bone (59.0%), switchover Tl-ethanol fraction dominated in the muscle (68.3%). This study has shown that Tl can be easily taken up by fish during 28-days-period and largely distributed in non-detoxified tissues especially muscle, in which concurrent risks of high Tl-total burden and high levels of Tl in the form of easy migration fraction, posing possible risks to public health.

Determinants of Exposure to Potentially Toxic Metals in Pregnant Women of the DSAN-12M Cohort in the Recôncavo Baiano, Brazil.

Exposure to potentially toxic metals (PTM) threatens maternal and child health. We investigated the determinants of exposure to lead (Pb), cadmium (Cd), arsenic (As), and manganese (Mn) in 163 pregnant women from the Recôncavo Baiano, Brazil, enrolled in the DSAN-12M cohort. We measured these metals in biological samples (blood, toenails, and hair) and the Pb dust loading rates (RtPb) at their homes by graphite furnace atomic absorption spectrophotometry (GFAAS). Questionnaires were applied to collect sociodemographic and general habits data. Only 2.91% (n = 4) of the pregnant women had As levels above the detection limit. Few participants had levels above the recommended reference values for blood Pb (5.1; 95% CI: 2.1-10.1%), and Mn in hair or toenails (4.3; 95% CI: 2.3-10.1%). On the other hand, 61.1 (95% CI: 52.4-69.3%) had elevated blood Cd levels. After binary logistic regression, low socioeconomic status, domestic waste burning, being a passive smoker, multiparity, and renovating the house significantly increased the chances of having high levels of Mn, Pb, and Cd. We detected a worrying situation related to exposure to Cd, showing the urgency of implementing human biomonitoring in the general population, especially in situations of social vulnerability.

Sex-specific associations between cord blood lead and neurodevelopment in early life: The mother-child cohort (Shanghai, China)

The extent to which neurodevelopment is affected by prenatal lead exposure has not been conclusive. In addition, studies on the effects of sex on these relationships are inconsistent. The aim of this study was to investigate the impact of cord blood lead on neurodevelopment in children within sex subgroups. A total of 275 mother-child pairs from the Shanghai mother-child cohort were included. Umbilical cord blood lead was measured using graphite furnace atomic absorption spectrophotometry. The Bayley Scales for Infant Development-III (BSID-III) was used to measure the neurodevelopment of infants at the age of 18 ± 1.5 months. The median and interquartile range of cord blood lead levels in the total participants, male, and female children were 44.0 (24.5) μg/L, 44.0 (24.3) μg/L, and 46.0 (24.0) μg/L, respectively. According to multiple linear regression, cord blood lead concentrations showed a negative association with fine motor scores in all models associated with female children (β = −1.5; 95%confidence interval: −2.6, −0.4). However, prenatal lead levels were not associated with any of the BSID-III scores in male children. In addition, cord serum DHA was found positively related to fine motor scores in male children. Our findings suggest that prenatal lead exposure could lead to decreased motor function, although this phenomenon was only observed in female children. And DHA may be a protective factor against lead exposure in boys. Thus, further studies are needed to investigate the associations between prenatal lead exposure and neurobehavioral development, as well as the mechanism of sex differences.

Blood Lead Levels among Non-Occupationally Exposed Pregnant Women in Southern Thailand

Lead (Pb) is a heavy metal that is toxic to humans, especially children and pregnant women. In Thailand, guidelines exist to minimize lead exposure in pregnant women working in lead-related occupations. However, no guidelines exist for pregnant women who are not employed in these economic sectors. This cross-sectional study aimed to examine blood lead levels (BLLs) and related risk factors among 80 non-occupationally exposed pregnant women from the general population living in Nakhon Si Thammarat province, Southern Thailand. BLLs were determined by graphite furnace atomic absorption spectrophotometry. A validated questionnaire was adopted to interview participants which included demographic, consumer goods, supplement intake, and health factors. The mean BLL was 4.68 ± 1.55 µg/dL (95% CI 4.33–5.02) and 42.50% had BLLs ≥ 5 µg/dL. Higher education was the only demographic factor associated with BLLs ≥ 5 µg/dL (aOR 0.16, 95% CI 0.03–0.80, p = 0.027). Systolic blood pressure was also associated with BLLs ≥ 5 µg/dL (aOR 5.00, 95% CI 1.23–17.16, p = 0.023). However, consumer goods and supplement intake were not associated with BLLs. Our results indicate that pregnant women from the general population who were not in the risk exposure group had lead in their bodies. Except for education, demographics were not associated with pregnant women with BLLs. However, with health factors, even low BLLs had a small effect on systolic blood pressure. These data suggest a need for promoting health education and health interventions to prevent the dangers of lead exposure, especially for pregnant women and children.

Exploring the relationship between blood toxic metal(oid)s and serum insulin levels through benchmark modelling of human data: Possible role of arsenic as a metabolic disruptor

The major goal of this study was to estimate the correlations and dose-response pattern between the measured blood toxic metals (cadmium (Cd), mercury (Hg), chromium (Cr), nickel (Ni))/metalloid (arsenic (As)) and serum insulin level by conducting Benchmark dose (BMD) analysis of human data. The study involved 435 non-occupationally exposed individuals (217 men and 218 women). The samples were collected at health care institutions in Belgrade, Serbia, from January 2019 to May 2021. Blood sample preparation was conducted by microwave digestion. Cd was measured by graphite furnace atomic absorption spectrophotometry (GF-AAS), while inductively coupled plasma-mass spectrometry (ICP-MS) was used to measure Hg, Ni, Cr and As. BMD analysis of insulin levels represented as quantal data was done using the PROAST software version 70.1 (model averaging methodology, BMD response: 10%). In the male population, there was no correlation between toxic metal/metalloid concentrations and insulin level. However, in the female population/whole population, a high positive correlation for As and Hg, and a strong negative correlation for Ni and measured serum insulin level was established. BMD modelling revealed quantitative associations between blood toxic metal/metalloid concentrations and serum insulin levels. All the estimated BMD intervals were wide except the one for As, reflecting a high degree of confidence in the estimations and possible role of As as a metabolic disruptor. These results indicate that, in the case of As blood concentrations, even values higher than BMD (BMDL): 3.27 (1.26) (male population), 2.79 (0.771) (female population), or 1.18 (2.96) μg/L (whole population) might contribute to a 10% higher risk of insulin level alterations, meaning 10% higher risk of blood insulin increasing from within reference range to above reference range. The obtained results contribute to the current body of knowledge on the use of BMD modelling for analysing human data.

Bioaccumulation of cd and hg in Muscle of Juvenile Pacific Sharpnose Shark Rhizoprionodon longurio from the SE Gulf of California.

In this study, the concentrations of Cd and Hg were measured in muscle of juvenile individuals at an importan fishing ground in southeastern Gulf of California to assess the health risk to human consumers considering elemental levels and rate of shark consumption in NW Mexico. Twenty-eight individuals were sampled in September 2019. Quantification of Hg was made by cold vapor-atomic absorption spectrophotometry, analyses of Cd were made by graphite furnace atomic absorption spectrophotometry. In general, average Hg (1.27µg g-1 dry weight) concentrations were higher than Cd (0.059). In comparison to results of Cd and Hg in muscle of several species of genus Rhizoprionodon sp., our reported concentrations were comparable. Maximum permissible limits (Cd 0.5 and Hg 0.5µg g-1 wet weight) in fish products for human consumption were not exceeded. Health risk assessment to shark consumers indicated that Hg is of more concern than Cd but no hazards exist.

Leadcare® II Comparison with Graphite Furnace Atomic Absorption Spectrophotometry for Blood Lead Measurement in Peruvian Highlands

Peru is one of the countries with the highest lead contamination in the world. Biological monitoring has limitations due to the shortage of laboratories with validated methodologies for the measurement of blood lead, and it is necessary to use alternative methods for its measurement in high-altitude cities. We aimed to compare the blood lead levels (BLL) measured by the LeadCare II (LC) method and Graphite Furnace Atomic Absorption Spectrometry (GF-AAS). We measured the BLL of 108 children from the city of La Oroya. The mean and median BLL for GF-AAS were 10.77 ± 4.18 and 10.44 µg/dL, respectively; for the LC method, the mean was 11.71 ± 4.28 and the median was 11.60 µg/dL. We found a positive linear correlation (Rho = 0.923) between both methods. Notwithstanding, the Wilcoxon test suggests a significant difference between both methods (ρ = 0.000). In addition, the Bland–Altman analysis indicates that there is a positive bias (0.94) in the LC method, and this method tends to overestimate the BLL. Likewise, we performed a generalized linear model to evaluate the influence of age and hemoglobin on BLL. We found that age and hemoglobin had a significant influence on BLL measured by the LC method. Finally, we used two non-parametric linear regression methods (Deming and Passing-Bablok regression) to compare the LC method with the GF-AAS. We found that these methods differ by at least a constant amount, and there would be a proportional difference between both. Although in general there is a positive linear correlation, the results of both methods differ significantly. Therefore, its use in cities located at high altitudes (higher than 2440 m.a.s.l.) would not be recommended.

Serum cadmium positively correlates with inflammatory cytokines in patients with chronic obstructive pulmonary disease.

Cadmium is a ubiquitous toxic heavy metal and environmental toxicant. Inflammation exerts central roles in the process of chronic obstructive pulmonary disease (COPD). However, few epidemiological studies on the correlation between cadmium exposure and COPD are available. The aim of this study was to evaluate the correlations among serum cadmium, inflammatory cytokines and pulmonary function in COPD patients. All 940 COPD patients were finally recruited in this study. Demographic characteristics and clinical information were extracted. Fasting serum was collected. Serum cadmium was detected through graphite furnace atomic absorption spectrophotometry. Serum inflammatory cytokines were measured using enzyme-linked immunosorbent assay. All patients were classified into three groups according to the tertile division of serum cadmium concentration: low (<0.77 μg/L, L), medium (0.77-1.01 μg/L, M), and high (1.01 μg/L, H). Logistic regression analysis found that serum cadmium was inversely correlated with pulmonary function before and after adjusted confounding variables. When stratified by gender, serum cadmium was still negatively correlated with pulmonary function in COPD patients. Moreover, higher serum cadmium elevated CAT (COPD Assessment Test) score before and after adjusted confounding variables. Though a non-linear association between serum cadmium and inflammatory cytokines, serum cadmium was positively associated with inflammatory cytokines (TNF-α and MCP-1). TNF-α and MCP-1 exerted a partial mediator in the association between cadmium exposure and pulmonary function decline in COPD patients. Serum cadmium concentration is inversely correlated with pulmonary function among COPD patients. Inflammatory cytokines may be important mediators for cadmium-induced pulmonary function decline in COPD patients.

Assessment of Arsenic Levels in Water, Sediment, and Human Hair around Ie Seu’um Geothermal Manifestation Area, Aceh, Indonesia

The concentration of arsenic in water, sediment, and resident hair in the Ie Seu’um geothermal manifestation area has been analyzed using the Atomic Graphite Furnace Atomic Absorption Spectrophotometry (GF-AAS) method. Sediment and hair samples were prepared by wet digestion using an acid solution. The measurement results were validated by linearity, Limit of Detection (LoD), Limit of Quantification (LoQ), Relative Standard Deviation (%RSD), and %Recovery. The validation test showed that this method is very linear, sensitive, accurate, and precise with a correlation coefficient of 0.9999, LoD of 0.009 μg/L, LoQ of 0.027 μg/L, recovery values of 89.117–101.027% for hair samples and 88.337–105.175% for sediment samples, and RSD of 1.067%. The sample test results showed that the hot springs contained the highest arsenic with levels of 166.73 ± 0.0081 μg/L (IS1). In comparison, the water samples with the lowest arsenic levels were in the rivers that had not been in direct contact with the hot water (IS2) flow, which is 0.80 ± 0.0036 μg/L. All the river water samples that had been in contact with hot water were boreholes, and the resident boreholes located around hot water streams/rivers contaminated with arsenic were above the threshold. Only the river water that had not been in contact with hot water, refill water, and borehole waters outside the hot water flow were detected to be below the threshold level. All the sediment samples showed arsenic contamination, with levels ranging from 2.56–6.86 mg/kg, and it was still within the normal limits recommended by the National Oceanic and Atmospheric Administration (NOAA). Arsenic exposures in communities living around the Ie Seu’um geothermal area, Mesjid Raya Sub-District, Aceh Besar District, Aceh Province, were very high, where 9 out of 10 respondents were positive for arsenic with levels ranging from 54.59–164.57 mg/kg, which was already above the threshold set by the researchers.

Serum zinc level and its association with multidrug-resistant tuberculosis.

Zinc deficiency is evident in chronic diseases, but little is known about its association with multi-drug resistant tuberculosis (MDRTB). We aimed to measure serum zinc level in MDRTB patients and explore its association with MDRTB compared to drug-sensitive tuberculosis (DSTB). We recruited 107 MDRTB and 87 DSTB patients from a tuberculosis referral hospital in Bangladesh. After overnight fasting, 5 ml venous blood was collected from each patient to measure serum zinc level through graphite furnace atomic absorption spectrophotometry method. Multivariate logistic regression was done to measure its association with MDRTB. The mean age of all patients was 36 years, where 70% were male. About 27% MDRTB patients and 2.3% DSTB patients had low serum zinc level (P < 0.0001). An inverse correlation was observed between serum zinc level and duration of anti-TB therapy (r-value: -0.252, P < 0.01). Reduced serum zinc level (odds ratio, 0.957; 95% confidence interval 0.923-0.992) was found as a significant associating factor for MDRTB after adjusted with age, sex, occupation, residence, tobacco consumption, Bacillus Calmette-Guérin-vaccination, and duration of anti-TB therapy. A lower serum zinc level is significantly associated with MDRTB. The tuberculosis control program should address this in the MDRTB control strategy.