Toxic metal concentrations in cigarettes obtained from U.S. smokers in 2009: results from the International Tobacco Control (ITC) United States survey cohort

Quantitative profiling and baseline intervals of trace elements in healthy lung tissues

BACKGROUND

Human lung tissue, as an interface with the environment, is susceptible to various environmental pollutants, including trace metals. However, quantitative data on trace metals in human lung tissues remain poorly described.

METHODS

This study aimed to characterize the elemental composition of histologically healthy, unaffected parts of human lung tissues, associated with non-infective, non-infiltrative, and non-malignant diseases (n = 60) for essential (Cr, Mn, Fe, Co, Cu, Zn, and Se) and toxic trace elements (Sr, Ni, As, Cd, and Pb). Additionally, we investigated the influence of personal factors (sex, age, and smoking habits) on the examined trace element profiles, as well as between the trace elements correlations in the healthy human lungs.

RESULTS

Among the analyzed trace elements, Fe was the most prevalent, while As was the least prevalent in healthy lung tissues. Stratifying by age revealed significantly higher Cr and Co (less Sr, Ni, and Pb) and lower Se levels in older individuals (above 65 years) compared to their younger counterparts. Sex-based differences were also notable, with Cu and Co 1.2- and 2.3-fold higher levels in females than in males. Exploring the impact of smoking habits revealed a striking 10-fold increase in Cd levels in the lung tissues of smokers compared to non-smokers. Correlation analyses showed significant positive associations between concentrations of certain toxic and essential trace elements in healthy lung tissues.

CONCLUSIONS

This study could contribute to the establishment of baseline intervals for essential and toxic trace elements, valuable for toxicological and clinical assessment, in healthy, unaffected human lungs, and indicates the influence of sex, age, and smoking. However, further larger-scale studies are needed to make more stable conclusions.

Heavy Metal Exposure and Cardiovascular Disease

Heavy metals are harmful environmental pollutants that have attracted widespread attention due to their health hazards to human cardiovascular disease. Heavy metals, including lead, cadmium, mercury, arsenic, and chromium, are found in various sources such as air, water, soil, food, and industrial products. Recent research strongly suggests a connection between cardiovascular disease and exposure to toxic heavy metals. Epidemiological, basic, and clinical studies have revealed that heavy metals can promote the production of reactive oxygen species, which can then exacerbate reactive oxygen species generation and induce inflammation, resulting in endothelial dysfunction, lipid metabolism distribution, disruption of ion homeostasis, and epigenetic changes. Over time, heavy metal exposure eventually results in an increased risk of hypertension, arrhythmia, and atherosclerosis. Strengthening public health prevention and the application of chelation or antioxidants, such as vitamins and beta-carotene, along with minerals, such as selenium and zinc, can diminish the burden of cardiovascular disease attributable to metal exposure.

Associations between metals and metabolomic profiles related to diabetes among adults in a rural region

INTRODUCTION

Exposure to metals is associated with increased risk of type 2 diabetes (T2D). Potential mechanisms for metals-T2D associations involve biological processes including oxidative stress and disruption of insulin-regulated glucose uptake. In this study, we assessed whether associations between metal exposure and metabolite profiles relate to biological pathways linked to T2D.

MATERIALS AND METHODS

We used data from 29 adults rural Colorado residents enrolled in the San Luis Valley Diabetes Study. Urinary concentrations of arsenic, cadmium, cobalt, lead, manganese, and tungsten were measured. Metabolic effects were evaluated using untargeted metabolic profiling, which included 61,851 metabolite signals detected in serum. We evaluated cross-sectional associations between metals and metabolites present in at least 50% of samples. Primary analyses adjusted urinary heavy metal concentrations for creatinine. Metabolite outcomes associated with each metal exposure were evaluated using pathway enrichment to investigate potential mechanisms underlying the relationship between metals and T2D.

RESULTS

Participants had a mean age of 58.5 years (standard deviation = 9.2), 48.3% were female, 48.3% identified as Hispanic/Latino, 13.8% were current smokers, and 65.5% had T2D. Of the detected metabolites, 455 were associated with at least one metal, including 42 associated with arsenic, 22 with cadmium, 10 with cobalt, 313 with lead, 66 with manganese, and two with tungsten. The metabolic features were linked to 24 pathways including linoleate metabolism, butanoate metabolism, and arginine and proline metabolism. Several of these pathways have been previously associated with T2D, and our results were similar when including only participants with T2D.

CONCLUSIONS

Our results support the hypothesis that metals exposure may be associated with biological processes related to T2D, including amino acid, co-enzyme, and sugar and fatty acid metabolism. Insight into biological pathways could influence interventions to prevent adverse health outcomes due to metal exposure.

Correlates of whole blood metal concentrations among reproductive-aged Black women

BACKGROUND

Metals may influence reproductive health, but few studies have investigated correlates of metal body burden among reproductive-aged women outside of pregnancy. Furthermore, while there is evidence of racial disparities in exposure to metals among U.S. women, there is limited research about correlates of metal body burden among Black women.

OBJECTIVE

To identify correlates of whole blood metal concentrations among reproductive-aged Black women.

METHODS

We analyzed cross-sectional data from a cohort of 1664 Black women aged 23-35 years in Detroit, Michigan, 2010-2012. We collected blood samples and questionnaire data. We measured concentrations of 17 metals in whole blood using inductively-coupled plasma-mass spectrometer-triple quadrupole and total mercury using Direct Mercury Analyzer-80. We used multivariable linear regression models to identify sociodemographic, environmental, reproductive, and dietary correlates of individual metal concentrations.

RESULTS

In adjusted models, age was positively associated with multiple metals, including arsenic, cadmium, and mercury. Education and income were inversely associated with cadmium and lead. Current smoking was strongly, positively associated with cadmium and lead. Alcohol intake in the past year was positively associated with arsenic, barium, copper, lead, mercury, vanadium, and zinc. Having pumped gasoline in the past 24 h was positively associated with cadmium, chromium, and molybdenum. Having lived in an urban area for the majority of residence in Michigan was positively associated with arsenic, lead, and nickel. Higher water intake in the past year was positively associated with several metals, including lead. Fish intake in the past year was positively associated with arsenic, cesium, and mercury. We also observed associations with body mass index, season, and other environmental, reproductive, and dietary factors.

SIGNIFICANCE

We identified potential sources of exposure to metals among reproductive-aged Black women. Our findings improve understanding of exposures to metals among non-pregnant reproductive-aged women, and can inform policies in support of reducing disparities in exposures.

IMPACT STATEMENT

There are racial disparities in exposures to metals. We analyzed correlates of blood metal concentrations among reproductive-aged Black women in the Detroit, Michigan metropolitan area. We identified sociodemographic, anthropometric, lifestyle, environmental, reproductive, and dietary correlates of metal body burden. Age was positively associated with several metals. Education and income were inversely associated with cadmium and lead, indicating socioeconomic disparities. We identified potential exposure sources of metals among reproductive-aged Black women, including smoking, environmental tobacco smoke, pumping gasoline, living in an urban area, and intake of alcohol, water, fish, and rice.

Mechanisms of E-Cigarette Vape-Induced Epithelial Cell Damage

E-cigarette use has been reported to affect cell viability, induce DNA damage, and modulate an inflammatory response resulting in negative health consequences. Most studies focus on oral and lung disease associated with e-cigarette use. However, tissue damage can be found in the cardio-vascular system and even the bladder. While the levels of carcinogenic compounds found in e-cigarette aerosols are lower than those in conventional cigarette smoke, the toxicants generated by the heat of the vaping device may include probable human carcinogens. Furthermore, nicotine, although not a carcinogen, can be metabolized to nitrosamines. Nitrosamines are known carcinogens and have been shown to be present in the saliva of e-cig users, demonstrating the health risk of e-cigarette vaping. E-cig vape can induce DNA adducts, promoting oxidative stress and DNA damage and NF-kB-driven inflammation. Together, these processes increase the transcription of pro-inflammatory cytokines. This creates a microenvironment thought to play a key role in tumorigenesis, although it is too early to know the long-term effects of vaping. This review considers different aspects of e-cigarette-induced cellular changes, including the generation of reactive oxygen species, DNA damage, DNA repair, inflammation, and the possible tumorigenic effects.

Determinants affecting the blood mercury levels of preschool children in Shanghai, China: A cross-sectional study

Infants and children are vulnerable to mercury (Hg)-induced toxicity, which has detrimental effects on their neurological development. This study measured blood Hg levels (BMLs) and identified potential factors influencing BMLs, including demographic and socioeconomic factors, lifestyle, and daily dietary habits, among 0 to 7-year-old children in Shanghai. Our study recruited 1474 participants, comprising 784 boys and 690 girls. Basic demographic and lifestyle information were obtained and blood Hg were analyzed using the Direct Mercury Analyzer 80. The blood Hg concentrations of children in Shanghai ranged from 0.01 to 17.20 μg/L, with a median concentration of 1.34 μg/L. Older age, higher familial socioeconomic status, higher residential floors, and a higher frequency of consuming aquatic products, rice, vegetables, and formula milk were identified as risk factors. Other potential influencing factors including the mother's reproductive history (gravidity and parity), smoking (passive smoking), supplementation of fish oil and calcium need to be further investigated. These findings can be useful in establishing appropriate interventions to prevent children's high blood Hg concentrations in Shanghai and other similar metropolitan cities.

Blood and Urinary Metal Levels among Exclusive Marijuana Users in NHANES (2005-2018)

BACKGROUND

Marijuana is the third most used drug in the world.

OBJECTIVES

Because the cannabis plant is a known scavenger of metals, we hypothesized that individuals who use marijuana will have higher metal biomarker levels compared with those who do not use.

METHODS

We combined data from the National Health and Nutrition Examination Survey (2005-2018) for n = 7,254 participants, classified by use: non-marijuana/non-tobacco, exclusive marijuana, exclusive tobacco, and dual marijuana and tobacco use. Five metals were measured in blood and 16 in urine using inductively coupled plasma mass spectrometry; urinary metals were adjusted for urinary creatinine.

RESULTS

Participants reporting exclusive marijuana use compared with non-marijuana/non-tobacco use had statistically significantly higher mean cadmium levels in blood [1.22 μ g / L (95% CI: 1.11, 1.34); p < 0.001 ] and urine [1.18 μ g / g (95% CI: 1.0, 1.31); p = 0.004 ] and statistically significantly higher mean lead levels in blood [1.27 μ g / dL (95% CI: 1.07, 1.50); p = 0.006 ] and urine [1.21 μ g / g (95% CI: - 0.006 , 1.50); p = 0.058 ].

DISCUSSION

Our results suggest marijuana is a source of cadmium and lead exposure. Research regarding cannabis use and cannabis contaminants, particularly metals, should be conducted to address public health concerns related to the growing number of cannabis users. https://doi.org/10.1289/EHP12074.

Impacts of cigarette smoking on blood circulation: do we need a new approach to blood donor selection?

Smoking is a major public health problem and is considered the leading cause of preventable death worldwide. Gas-phase smoke carries bioactive substances and toxic compounds, affecting human health and reducing life spans. The negative effects of smoking on red blood cell (RBC) quality include destroying RBCs and increasing carboxy hemoglobin (COHb). Smoking increases the concentrations of heavy metals such as cadmium (Cd) and lead (Pb) in the blood. Moreover, tobacco smoking has been found to be associated with heightened platelet (PLT)-dependent thrombin level which will induce a prothrombotic state. Smoking may affect the blood circulation of donors, and subsequently the blood components, and ultimately the recipients of transfusion. Nevertheless, there are no restrictions on smoking for volunteer blood donor screenings currently. We reviewed the articles about the influence of smoking on smokers' blood circulation as well as the impact of donated blood products on transfusion when these smokers act as blood donors. We aim to attract blood collection centers' attention to strengthen the management of blood donors who smoke, avoiding their use in massive transfusion protocol and susceptible recipients, especially pediatric ones.

Detection of Cadmium and Lead in Kidney Stones. Associations with Patient Demographics, Stone Composition, and Smoking

BACKGROUND

Kidney stones are a highly prevalent disease worldwide. Additionally, both environmental and occupational exposure to Pb and Cd continue to be prevalent globally and can result in renal toxicity. The objective of this study was to examine the potential presence of Pb and Cd in kidney stones, and to assess for correlation with demographic factors including smoking, gender, age, and kidney stone matrix composition.

METHODS

Patient kidney stones (n = 96) were analyzed using Fourier transform infrared spectroscopy to identify the stone constituents. Cd and Pb concentrations (µg/g) were determined by inductively coupled plasma mass spectrometry. Cd and Pb concentrations were correlated using bivariable and multivariable statistical analysis with demographic factors (age, gender, smoking status), and kidney stone composition.

RESULTS

Kidney stone Cd (median 0.092 µg/g, range 0.014 to 2.46) and Pb concentrations (median 0.95 µg/g, range 0.060 to 15.4) were moderately correlated (r = 0.56, P < 0.0001). Cd concentrations were positively associated with patient history of smoking, patient age, and calcium oxalate monohydrate levels while negatively associated with struvite and uric acid/uric acid dihydrate. Pb concentrations were positively associated with females and apatite levels while negatively associated with uric acid/uric acid dihydrate. After holding constant other stone type composition levels, smoking status, and age, both Pb and Cd were positively associated with apatite and negatively associated with uric acid/uric acid dihydrate, struvite, and calcium carbonate.

CONCLUSIONS

Cd and Pb kidney stone concentrations are associated with specific kidney stone types. Cd and Pb kidney stone concentrations are both associated with smoking.

Assessment of heavy metal levels in roll-your-own cigarette and water pipe tobacco blends

The increased consumption of roll-your-own (RYO) cigarettes and water pipe (hookah), both globally and in Bulgaria, necessitated the current investigation aimed at the assessment of heavy metal levels in the tobacco blends used in those products. The concentrations of Mn, Zn, Cu, Cd, Pb, and Ni were determined by AAS in five brands of RYO tobacco (R1-R5) and seven brands of water pipe tobacco (W1- W7), all distributed on Bulgarian market. The average heavy metal contents (mg/kg) in the two types of tobacco blends, RYO and water pipe, respectively, were as follows: Mn - 214.20 and 37.89; Zn - 31.90 and 134.87; Cu - 12.06 and 10.07; Cd - 0.80 and 1.33; Pb - 1.60 and 3.57; Ni - 1.36 and 0.80. RYO cigarette tobaccos contained higher concentration of Mn, Cu and Ni, while water pipe tobaccos - Zn, Cd and Pb. Strong correlations were found between Cu and Zn (r=0.81), Cu and Cd (r=0.90) in RYO tobacco blends, and between Cu and Zn (r=0.86) - in water pipe blends, respectively. The results from the study give reason to recommend that this information be provided to the consumers, who consider the regarded tobacco products as a safer alternative to conventional cigarettes.

Multi-matrix biomonitoring approach to assess exposure to metals and trace elements in the Lebanese population and associations with drinking water consumption

This study is the first attempt to assess exposure to metals and trace elements in subgroups of the Lebanese population using a multi-matrix biomonitoring approach. Concentrations of 11 metals and trace elements (aluminum (Al), arsenic (As), cadmium (Cd), chromium (Cr), copper (Cu), iron (Fe), lead (Pb), manganese (Mn), selenium (Se), uranium (U), zinc (Zn)) were measured in urine, hair and toenails. Biological levels were compared according to age, sex, smoking status, socioeconomic status, geographical area and drinking water source. While most urinary and toenail concentrations of metals and trace elements were not different between males and females, measured concentrations of several elements in hair were higher in females compared to males. Urinary concentrations of some metals (Al, Cu, Se and Zn) were higher in children compared to teenagers and adults. Hair and toenail concentrations of several elements (As, Cd, Pb, Mn, Se in hair and toenails plus Al, Fe in toenails) were also significantly higher in children compared to teenagers and/or adults. Smoking status had no influence on metal and trace element concentrations. Levels of Cd, Pb and Mn were also higher in samples from subgroups with lower economic status (Cd and Pb in the three matrices and Mn in hair and toenails). Very few correlations were identified between sources of drinking water and urine, hair, and toenail concentrations of metals and trace elements. However, a correlation was observed between hair and toenails levels of As, Cd and Pb. Overall, results highlight that a special attention should be given to metal and trace element exposure in this population (including Pb, As, Cd, Mn, and Se). It could be relevant to scale up this kind of investigation with a large human biomonitoring initiative in the Lebanese population in order to generalize results, and assess trends over time.

Trace elements repartition in body fluids, hair and organs in an autopsied population evaluated by ICP-MS high resolution

Exposure to metals and trace elements (TE) is universal and can cause toxicity in case of excessive exposure. We evaluated the concentrations and tissue distribution of 39 TE using high-resolution ICP-MS after total mineralization by microwave in twenty autopsied French subjects. We found a globally homogeneous distribution of TE in the body, with some accumulations in agents, involved in respiratory pathologies and classified as carcinogens, in the lungs. The liver, an organ of metabolism, appeared to concentrate Co, Fe, La, Mn, Mo, Pb and Zn. Fe seemed to accumulate in the spleen, the organ of hematopoiesis. The kidney showed high concentrations of some TE, which can cause nephrotoxicity. The use of microwave mineralization and high-resolution ICP-MS allowed accurate quantification and a very high sensitivity, without spectral interferences. The results obtained in this study could be used to support the interpretation of post-mortem metal concentrations in tissues.

Sperm concentration and semen volume increase after smoking cessation in infertile men

Smoking has negative reproductive consequences. This study investigated the effect of smoking cessation on the main semen parameters. We included 90 participants who applied to our infertility clinic and smoked at least 20 cigarettes a day for at least 1 year. Of the 90 participants, 48 were in the study group and 42 were in the control group. Semen analysis was performed before and at least 3 months after quitting smoking in the study group. Semen analysis was repeated at baseline and at least 3 months later in the control group. Semen parameters such as volume, sperm concentration, total sperm count, morphology, and motility were evaluated according to the World Health Organization criteria. Patient characteristics as well as the duration of the smoking period, the number of cigarettes smoked per day and the time elapsed since smoking cessation were recorded. The mean age of the participants was 34.69 ± 5.3 years, and the duration of infertility was 34.12 ± 12.1 months (n = 90). The number of cigarettes smoked per day was 30.14 ± 6.69, and the smoking time was 8.31 ± 3.53 years. The average time to quit smoking was 104.2 ± 11.51 days (n = 48). A significant increase in semen volume, sperm concentration and total sperm count was observed 3 months after smoking cessation (2.48 ± 0.79 ml vs. 2.90 ± 0.77 ml, p = 0.002; 18.45 × 10⁶/ml ± 8.56 vs. 22.64 × 10⁶/ml ± 11.69, p = 0.001; 45.04 ± 24.38 × 10⁶ vs. 65.1 ± 34.9 × 10⁶, p < 0.001, respectively). This study showed that smoking cessation had a positive effect on sperm concentration, semen volume, and total sperm count. Although smoking cessation contributed positively to sperm motility and morphology, the difference was not statistically significant.

Source identification and health risk assessments of heavy metals in indoor dusts of Ilorin, North central Nigeria

BACKGROUND AND PURPOSE

Exposure to heavy metals (HMs) in indoor dusts is a serious public concern that is linked to a myriad of deleterious health outcomes. The objectives of this study are to estimate the contamination levels of HMs in indoor dusts of different residential areas in Ilorin, Nigeria; identify HMs sources in different residential areas; and evaluate human health risks of HMs in selected residential areas.

METHODS

Indoor dust sampling was conducted in ten randomly selected from low, medium and high population density residential areas of Ilorin, Nigeria. Ten HMs concentration levels, their health risk implication and the associated potential ecological risks were evaluated.

RESULTS

The mean concentration levels measured for Fe, Pb, Zn, As, Co, Cr, Cu, Cd, Mn and Ni were 38.99, 5.74, 3.99, 0.08, 2.82, 2.13, 0.47, 0.60, 6.45 and 1.09 mg/kg, respectively. Positive Matrix Factorization (PMF) model was applied to ascertain sources of HMs in sampled indoor dust. Percentage contribution from oil-based cooking (29.82%) and transportation (29.77%) represented the highest source to HM concentrations among the six factors identified. The results of the various pollution indices employed showed that Pb, Zn, As, Co, Cr, Cu, Mn and Ni contributed moderately to HMs concentration levels in the sampled dusts. Cd had highest potential ecological risk factor E r i of between 160 and 320. The average values of Enrichment Factors (EFs) obtained aside from Fe used as the reference metal, ranged between 8.46 (As) and 2521.61(Cd). Health risk assessment results revealed that children are the most susceptible to the risks associated with HMs bound indoor dust than the adults. The percentage risk contributions of Hazard Quotient via ingestion route (HQ_ing) in Hazard Index (HI) for non-cancer risk of indoor HMs were 93.17% and 69.87% in children and adults, respectively. Likewise, the percentage cancer risks contribution through ingestion pathway (CR_ing) were higher than cancer risks through inhalation and dermal pathways (CR_inh and CR_dermal), accounting for 99.84% and 97.04% of lifetime cancer risk in children and adults, respectively. The contamination level of Cd recorded is of great concern and signifies very strong contribution from anthropogenic sources.

CONCLUSION

This study has further revealed the levels of HMs in typical African residential settings that could be used by relevant stakeholders and policy makers in developing lasting control measures.

SUPPLEMENTARY INFORMATION

The online version contains supplementary material available at 10.1007/s40201-021-00778-8.

Epigenetics at the Intersection of COVID-19 Risk and Environmental Chemical Exposures

PURPOSE OF REVIEW

Several environmental contaminants have been implicated as contributors to COVID-19 susceptibility and severity. Immunomodulation and epigenetic regulation have been hypothesized as mediators of this relationship, but the precise underlying molecular mechanisms are not well-characterized. This review examines the evidence for epigenetic modification at the intersection of COVID-19 and environmental chemical exposures.

RECENT FINDINGS

Numerous environmental contaminants including air pollutants, toxic metal(loid)s, per- and polyfluorinated substances, and endocrine disrupting chemicals are hypothesized to increase susceptibility to the SARS-CoV-2 virus and the risk of severe COVID-19, but few studies currently exist. Drawing on evidence that many environmental chemicals alter the epigenetic regulation of key immunity genes and pathways, we discuss how exposures likely perturb host antiviral responses. Specific mechanisms vary by contaminant but include general immunomodulation as well as regulation of viral entry and recognition, inflammation, and immunologic memory pathways, among others. Associations between environmental contaminants and COVID-19 are likely mediated, in part, by epigenetic regulation of key immune pathways involved in the host response to SARS-CoV-2.

Exposure of Mice to Thirdhand Smoke Modulates In Vitro and In Vivo Platelet Responses

Smoking is a risk factor for a variety of deleterious conditions, such as cancer, respiratory disease and cardiovascular disease. Thrombosis is an important and common aspect of several cardiovascular disease states, whose risk is known to be increased by both first- and secondhand smoke. More recently, the residual cigarette smoke that persists after someone has smoked (referred to as thirdhand smoke or THS) has been gaining more attention, since it has been shown that it also negatively affects health. Indeed, we have previously shown that 6-month exposure to THS increases the risk of thrombogenesis. However, neither the time-dependence of THS-induced thrombus formation, nor its sex dependence have been investigated. Thus, in the present study, we investigated these issues in the context of a shorter exposure to THS, specifically 3 months, in male and female mice. We show that the platelets from 3-month THS-exposed mice exhibited enhanced activation by agonists. Moreover, we also show that mice of both sexes exposed to THS have decreased tail bleeding as well as decreased thrombus occlusion time. In terms of the role of sex, intersex disparities in thrombus development and hemostasis as well as in platelet aggregation were, interestingly, observed. Together, our findings show that exposing mice to THS for 3 months is sufficient to predispose them to thrombosis; which seems to be driven, at least in part, by an increased activity in platelets, and that it does not manifest equally in both sexes.

Environmental metal exposures and kidney function of Guatemalan sugarcane workers

BACKGROUND

Exposure to environmental metals can cause nephrotoxicity. There is an international epidemic of chronic kidney disease of unknown cause (CKDu). Whether metal exposures contribute to kidney dysfunction in populations at risk for CKDu remains unresolved.

OBJECTIVE

Urinary metals (arsenic, cadmium, nickel, and uranium) were examined in 222 sugarcane cutters in Guatemala at three time points over 1 year.

METHODS

We explored the relationships between metal concentrations and markers of kidney function using multivariable linear mixed-effect models.

RESULTS

Arsenic, cadmium, and nickel were detected in the majority of the 340 urine samples and were generally within limits previously considered to be nonnephrotoxic. Nevertheless, higher urine cadmium was inversely associated with estimated glomerular filtration rate (eGFR) (β: -4.23, 95% confidence interval [CI]: -6.92, -1.54) and positively associated with neutrophil gelatinase-associated lipocalin (NGAL) (β: 2.92, 95% CI: 1.20, 4.64). Higher urine arsenic was also inversely associated with eGFR (β: -4.36, 95% CI: -7.07, -1.64).

SIGNIFICANCE

Our findings suggest that exposures to metals, including cadmium and arsenic, might contribute to kidney toxicity seen in workers at risk for CKDu. These findings are consistent with the potential for metal nephrotoxicity at lower than expected levels in the setting of manual work in a very hot environment.

Analysis and differentiation of tobacco-derived and synthetic nicotine products: Addressing an urgent regulatory issue

There is significant regulatory and economic need to distinguish analytically between tobacco-derived nicotine (TDN) and synthetic nicotine (SyN) in commercial products. Currently, commercial e-liquid and oral pouch products are available that contain tobacco-free nicotine, which could be either extracted from tobacco or synthesized. While tobacco products that contain TDN are regulated by FDA Center for Tobacco Products, those with SyN are currently not in the domain of any regulatory authority. This regulatory difference provides an economic incentive to use or claim the use of SyN to remain on the market without submitting a Premarket Tobacco Product Application. TDN is ~99.3% (S)-nicotine, whereas SyN can vary from racemic (50/50 (R)/(S)) to ≥ 99% (S)-nicotine, i.e., chemically identical to the tobacco-derived compound. Here we report efforts to distinguish between TDN and SyN in various samples by characterizing impurities, (R)/(S)-nicotine enantiomer ratio, (R)/(S)-nornicotine enantiomer ratio, and carbon-14 (14C) content. Only 14C analysis accurately and precisely differentiated TDN (100% 14C) from SyN (35-38% 14C) in all samples tested. 14C quantitation of nicotine samples by accelerator mass spectrometry is a reliable determinate of nicotine source and can be used to identify misbranded product labelled as containing SyN. This is the first report to distinguish natural, bio-based nicotine from synthetic, petroleum-based nicotine across a range of pure nicotine samples and commercial e-liquid products.

The Effects of Environmental Contaminant Exposure on Reproductive Aging and the Menopause Transition

PURPOSE OF REVIEW

Menopause marks the end of a woman's reproductive lifetime. On average, natural menopause occurs at 51 years of age. However, some women report an earlier age of menopause than the national average. This can be problematic for women who delay starting a family. Moreover, early onset of menopause is associated with increased risk of cardiovascular disease, depression, osteoporosis, and premature death. This review investigates associations between exposure to endocrine-disrupting chemicals (EDCs) and earlier onset of menopause.

RECENT FINDINGS

Recent data suggest exposure to certain EDCs may accelerate reproductive aging and contribute to earlier onset of menopause. Human and rodent-based studies identify positive associations between exposure to certain EDCs/environmental contaminants and reproductive aging, earlier onset of menopause, and occurrence of vasomotor symptoms. These findings increase our understanding of the detrimental effects of EDCs on female reproduction and will help lead to the development of strategies for the treatment/prevention of EDC-induced reproductive aging.

The Cause of Alzheimer's Disease: The Theory of Multipathology Convergence to Chronic Neuronal Stress

The field of Alzheimer's disease (AD) research critically lacks an all-inclusive etiology theory that would integrate existing hypotheses and explain the heterogeneity of disease trajectory and pathologies observed in each individual patient. Here, we propose a novel comprehensive theory that we named: the multipathology convergence to chronic neuronal stress. Our new theory reconsiders long-standing dogmas advanced by previous incomplete theories. Firstly, while it is undeniable that amyloid beta (Aβ) is involved in AD, in the seminal stage of the disease Aβ is unlikely pathogenic. Instead, we hypothesize that the root cause of AD is neuronal stress in the central nervous system (CNS), and Aβ is expressed as part of the physiological response to protect CNS neurons from stress. If there is no return to homeostasis, then Aβ becomes overexpressed, and this includes the generation of longer forms that are more toxic and prone to oligomerization. Secondly, AD etiology is plausibly not strictly compartmentalized within the CNS but may also result from the dysfunction of other physiological systems in the entire body. This view implies that AD may not have a single cause, but rather needs to be considered as a spectrum of multiple chronic pathological modalities converging to the persistent stressing of CNS neurons. These chronic pathological modalities, which include cardiovascular disease, metabolic disorders, and CNS structural changes, often start individually, and over time combine with other chronic modalities to incrementally escalate the amount of stress applied to CNS neurons. We present the case for considering Aβ as a marker of neuronal stress in response to hypoxic, toxic, and starvation events, rather than solely a marker of AD. We also detail numerous human chronic conditions that can lead to neuronal stress in the CNS, making the link with co-morbidities encountered in daily clinical AD practice. Finally, we explain how our theory could be leveraged to improve clinical care for AD and related dementia in personalized medicine paradigms in the near future.

Smoking and degenerative spinal disease: A systematic review

Smoking is a major cause of morbidity and mortality worldwide and is responsible for the death of more than 8 million people per year globally. Through a systematic literature review, we aim to review the harmful effects of tobacco smoking on degenerative spinal diseases (DSD). DSD is a debilitating disease and there is a need to identify if smoking can be an attributable contender for the occurrence of this disease, as it can open up avenues for therapeutic options. Sources such as PubMed and Embase were used to review literature, maintaining tobacco smoking and spinal diseases as inclusion factors, excluding any article that did not explore this relationship. Risk of bias was assessed using analysis of results, sample size and methods and limitations. Upon review of the literature, tobacco smoking was found to be a major risk factor for the occurrence of DSDs, particularly lumbar spinal diseases. Smokers also experienced a greater need for surgery and greater postoperative wound healing complications, increased pain perception, delay in recovery and decreased satisfaction after receiving surgery. These effects were noted along the entire spine. Many mechanisms of action have been identified in the literature that provide plausible pictures of how smoking leads to spinal degeneration, exploring possible primary targets which can open up opportunities to develop potential therapeutic agents. More studies on cervical and thoracic spinal degeneration would be beneficial in identifying the effect of nicotine on these spinal levels. Some limitations included insufficient sample size, inconclusive evidence and lack of sufficient repeat studies. However, there appears to be a sufficient amount of research on smoking directly contributing to lumbar spinal pathology.

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Smoking is a risk factor for the occurence of degenerative spinal disease (DSD).

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There are numerous pathological mechanisms attributed to spinal pathology by smoking.

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Smoking appears to be a significant risk factor for lumbar DSDs, with smoke studies also suggesting its role in cervical DSDs.

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There is insufficient research on the effect of smoking on the thoracic spine.

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Smoking leads to worse outcomes and potential complications post-surgery, as well as increased pain perception and poorer subjective response post-surgery.

Inferred inactivation of the Cftr gene in the duodena of mice exposed to hexavalent chromium (Cr(VI)) in drinking water supports its tumor-suppressor status and implies its potential role in Cr(VI)-induced carcinogenesis of the small intestines

Carcinogenicity of hexavalent chromium [Cr (VI)] has been supported by a number of epidemiological and animal studies; however, its carcinogenic mode of action is still incompletely understood. To identify mechanisms involved in cancer development, we analyzed gene expression data from duodena of mice exposed to Cr(VI) in drinking water. This analysis included (i) identification of upstream regulatory molecules that are likely responsible for the observed gene expression changes, (ii) identification of annotated gene expression data from public repositories that correlate with gene expression changes in duodena of Cr(VI)-exposed mice, and (iii) identification of hallmark and oncogenic signature gene sets relevant to these data. We identified the inactivated CFTR gene among the top scoring upstream regulators, and found positive correlations between the expression data from duodena of Cr(VI)-exposed mice and other datasets in public repositories associated with the inactivation of the CFTR gene. In addition, we found enrichment of signatures for oncogenic signaling, sustained cell proliferation, impaired apoptosis and tissue remodeling. Results of our computational study support the tumor-suppressor role of the CFTR gene. Furthermore, our results support human relevance of the Cr(VI)-mediated carcinogenesis observed in the small intestines of exposed mice and suggest possible groups that may be more vulnerable to the adverse outcomes associated with the inactivation of CFTR by hexavalent chromium or other agents. Lastly, our findings predict, for the first time, the role of CFTR inactivation in chemical carcinogenesis and expand the range of plausible mechanisms that may be operative in Cr(VI)-mediated carcinogenesis of intestinal and possibly other tissues.

Trajectory of inhaled cadmium ultrafine particles in smokers

Introduction

Tobacco smoking is a significant source of cadmium exposure among smokers. Most of inhaled heavy metals, including cadmium, are attached to ultrafine particles (UFPs) surface. A low inhaled UFP content in exhaled breath condensate reflects a high inflammatory status of airways. Increased respiratory epithelial permeability and translocation to the circulation is the proposed mechanism. UFP recovered from smokers’ airways have high levels of cadmium compared with the airways of non-smokers.

Methods

Urine was collected from 22 smokers subjects and 43 non-smokers. Samples were analysed for UFP and cadmium content. UFP were measured in urine samples by means of the NanoSight LM20 system (NanoSight, UK). A Niton XL3 X-ray fluorescence spectrometer analyzer (Thermo Fischer Scientific, Germany) quantified heavy metal contents in the urine samples.

Results

Smokers had elevated UFP and cadmium content in urine compared with non-smokers (4.6 E8/mL and 20.6 ppm vs 3.4 E8/mL and 18.5 ppm, p=0.05 and p=0.05, respectively). Smokers had elevated levels of lead and rubidium compared with non-smokers (8.9 ppm and 27 ppm vs 7.8 ppm and 2 ppm, p=0.05 and p=0.04, respectively)

Discussion

We suggest that the trajectory of cadmium-related UFP in smokers begins by its inhalation into the airways. The UFPs induce inflammation and oxidative stress in the small airways, are subsequently translocated from the interstitium to the circulation and are finally detected and secreted in urine

Evaluating tissue levels of the eight trace elements and heavy metals among esophagus and gastric cancer patients: A comparison between cancerous and non-cancerous tissues

BACKGROUND

Considering the affecting role of environmental factors including trace elements and heavy metals on the upper gastrointestinal (GI) cancers, there is paucity of empirical research in tissue evaluations.

OBJECTIVES

The present study aimed to measure the tissue content of some trace elements and heavy metals such as zinc (Zn), chromium (Cr), manganese (Mn), tin (Sn), copper (Cu), aluminum (Al), lead (Pb), and iron (Fe) in esophagus and gastric cancerous tissues compared to the adjacent healthy tissues.

METHODS

In a cross-sectional study, the aforementioned trace elements and heavy metals were evaluated among patients with esophagus and gastric cancers. During endoscopy, multiple samples were taken from cancerous lesions and the adjacent healthy tissues. The classic flame atomic absorption spectroscopy (FAAS) method was employed as the study framework.

RESULTS

Fifty patients with the mean age of 53.92 ± 8.73 were enrolled in the current study. Thirteen patients suffered from esophageal cancer and thirty-seven patients were afflicted with gastric cancer. The results revealed significant differences in the median concentrations of Zn, Cr, Sn and, Cu (P < 0.05) between the two groups. Although there were no significant changes in the tissue content in the esophageal samples, in the median concentrations of Zn, Cr and, Sn (P < 0.05) in gastric tissues, significant differences were observed. Further, the results indicated that gender enacted an affecting role in the level of some trace elements and heavy metals.

CONCLUSION

The tissue contents of some elements were altered in gastric and esophageal cancers; this difference may reflect the underlying mechanism of cellular changing during the tumorigenesis or direct exposure of these elements. It seems that under the shade of other coexisting risk factors, larger cohort studies are suggested to be conducted to investigate other probable aspects in this area of interest.

Tobacco Smoke Exposure and Urinary Cadmium in Women from Northern Mexico

Cadmium (Cd), a carcinogenic metal also related to reproductive and cardiovascular diseases, is contained in tobacco and elevated concentrations of it in humans have been consistently associated with first-hand tobacco smoke; however, there is scarce and inconclusive evidence of the relationship between Cd and secondhand smoke (SHS) exposure. Our aim was to evaluate the association between exposure to tobacco, both active and SHS, with urinary Cd concentrations in Mexican women. In a cross-sectional analysis that included 998 women living in northern Mexico, we measured the concentration of creatinine-adjusted urinary Cd (µg-cadmium/g-creatinine) using inductively coupled plasma triple quadrupole (ICP-QQQ) in tandem mass spectrometry mode (MS/MS). We gathered tobacco smoking information through an in-person interview and formed seven groups: non-smokers without SHS exposure; non-smokers with SHS exposure; ex-smokers without SHS exposure <1 year of quitting; ex-smokers without SHS exposure ≥1 year of quitting, ex-smokers with SHS exposure <1 year of quitting; ex-smokers with SHS exposure ≥1 year of quitting and current smokers. The interview also yielded sociodemographic characteristics. We used linear multivariable regression models to estimate the association between Cd concentrations and tobacco smoke exposure. Compared to non-smokers without SHS exposure, we found higher Cd concentrations in ex-smokers with SHS exposure <1 year of quitting and current smokers (adjusted geometric means 0.51 vs. 1.01 and 0.69 µg-cadmium/g-creatinine, respectively). Our results do not support a conclusion that SHS exposure is a source of Cd body burden.

Urinary metals and maternal circulating extracellular vesicle microRNA in the MADRES pregnancy cohort

Exposure to metals increases risk for pregnancy complications. Extracellular vesicle (EV) miRNA contribute to maternal-foetal communication and are dysregulated in pregnancy complications. However, metal impacts on maternal circulating EV miRNA during pregnancy are unknown. Our objective was to investigate the impact of multiple metal exposures on EV miRNA in maternal circulation during pregnancy in the MADRES Study. Associations between urinary concentrations of nine metals and 106 EV miRNA in maternal plasma during pregnancy were investigated using robust linear regression (N = 231). Primary analyses focused on metal-miRNA associations in early pregnancy (median: 12.3 weeks gestation). In secondary analyses, we investigated associations with late pregnancy miRNA counts (median: 31.8 weeks gestation) in a subset of participants (N = 184) with paired measures. MiRNA associated with three or more metals (P_FDR<0.05) were further investigated using Bayesian Kernel Machine Regression (BKMR), an environmental mixture method. Thirty-five miRNA were associated (P_FDR<0.05) with at least one metal in early pregnancy. One association (an inverse association between cobalt and miR-150-5p) remained statistically significant when evaluating late pregnancy miRNA counts. Eight miRNA (miR-302b-3p, miR-199a-5p, miR-188-5p, miR-138-5p, miR-212-3p, miR-608, miR-1272, miR-19b-3p) were associated with three metals (barium, mercury, and thallium) in early pregnancy, and their predicted target genes were enriched in pathways important for placental development. Results were consistent when using BKMR. Early pregnancy exposure to barium, mercury, and thallium may have short-term impacts on a common set of EV miRNA which target pathways important for placental development.

The Impact of Sedentary Lifestyle, High-fat Diet, Tobacco Smoke, and Alcohol Intake on the Hematopoietic Stem Cell Niches

Hematopoietic stem and progenitor cells maintain hematopoiesis throughout life by generating all major blood cell lineages through the process of self-renewal and differentiation. In adult mammals, hematopoietic stem cells (HSCs) primarily reside in the bone marrow (BM) at special microenvironments called “niches.” Niches are thought to extrinsically orchestrate the HSC fate including their quiescence and proliferation. Insight into the HSC niches mainly comes from studies in mice using surface marker identification and imaging to visualize HSC localization and association with niche cells. The advantage of mouse models is the possibility to study the 3-dimensional BM architecture and cell interactions in an intact traceable system. However, this may not be directly translational to human BM. Sedentary lifestyle, unhealthy diet, excessive alcohol intake, and smoking are all known risk factors for various diseases including hematological disorders and cancer, but how do lifestyle factors impact hematopoiesis and the associated niches? Here, we review current knowledge about the HSC niches and how unhealthy lifestyle may affect it. In addition, we summarize epidemiological data concerning the influence of lifestyle factors on hematological disorders and malignancies.

Comparison of serum concentrations of essential and toxic elements between cigarette smokers and non-smokers

The habit of smoking remains a severe public health problem. Heavy metals in cigarettes and mainstream smoke have been extensively investigated. This study has attempted to determine the essential and toxic elements in a biological sample of smokers and non-smokers. In this case-control study, 100 smokers were compared with 100 age- and gender-matched non-smoker healthy subjects. The smoker group was selected via the snowball sampling method. Serum concentrations of trace elements were determined using ICP-MS (Agilent 7900) for subsequent analysis. Data were analyzed by SPSS software using t test or Mann-Whitney U test along with chi-square test at the significant level of less than 0.05. The results of this study indicated that subjects in the smoker group compared with non-smokers had a significantly higher median of manganese (Mn) (11.5 [5.7-17.2] versus 6 [4-12.5] (μg/L), p = 0.003), copper (Cu) (40 [34-47.2] versus 34 [29-42] (μg/L), p = 0.005), arsenic (As) (39 [9-49.2] versus 12 [5-42] (μg/L), p = 0.007), thallium (Tl) (0.54 [0.27-0.68] versus 0.34 [0.11-0.66] (μg/L), p = 0.04), and lower iron (Fe) concentration (218 [156-508] versus 429 [192-573] (μg/L), p = 0.03). This study found that the concentrations of Mn, Cu, As, and TI in cigarette smokers were significantly higher than those obtained from the control group. These results can provide health policymakers with the necessary information to take public health measures towards preventive interventions in the community, though further studies are still warranted.

Cadmium Exchange with Zinc in the Non-Classical Zinc Finger Protein Tristetraprolin

Tristetraprolin (TTP) is a nonclassical CCCH zinc finger protein that regulates inflammation. TTP targets AU-rich RNA sequences of cytokine mRNAs forming a TTP/mRNA complex. This complex is then degraded, switching off the inflammatory response. Cadmium, a known carcinogen, triggers proinflammatory effects, and there is evidence that Cd increases TTP expression in cells, suggesting that Zn-TTP may be a target for cadmium toxicity. We sought to determine whether Cd exchanges with Zn in the TTP active site and measure the effect of RNA binding on this exchange. A construct of TTP that contains the two CCCH domains (TTP-2D) was employed to investigate these interactions. A spin-filter ICP-MS experiment to quantify the metal that is bound to the ZF after metal exchange was performed, and it was determined that Cd exchanges with Zn in Zn2-TTP-2D and that Zn exchanges with Cd in Cd2-TTP-2D. A native ESI-MS experiment to identify the metal-ZF complexes formed after metal exchange was performed, and M-TTP-2D complexes with singular and double metal exchange were observed. Metal exchange was measured in both the absence and presence of TTP's partner RNA, with retention of RNA binding. These data show that Cd can exchange with Zn in TTP without affecting function.

Direct imaging evidences of metal inorganic contaminants traced into cigarettes

Today, environmental health research on toxicological adverse effects of metal-inorganic materials diffused by cigarettes represents a new challenge for assessing new health risks directly related to the critical chemical-size features of the particles. Therefore, morpho-chemical analyses of hazardous particles become critical in response to the distinctive assumptions about the origin, evolution, and coexisting phases. Here, we report a detailed investigation through direct microscopy imaging of metal-inorganic contaminants for one traditional and two heat-not-burn commercial cigarettes of three different brands. Chemical-size studies revealed the critical presence of heavy metal-inorganic nanostructured microparticles on both paper and filter components of the cigarette, before and after smoking. The direct experimental imaging evidenced on how hazardous particles evolved in mass-size forming coexisting multi-phases of large agglomerate because of the persistence and accumulative effect of the heating puffing. The estimated porosity of the unsuitable engineered filters validated the allowed migration of micrometric pollutants independently from their intrinsic size-shape property. Furthermore, the inappropriate design of the filters made it an adverse sponge reservoir capable of collecting all possible hazardous chemical agents potentially toxic. These substantial results strongly support experimentally the tremendous effect of the smoke capable of transporting and manipulating a high amount of elusive particles, as a particles heat carrier.

Toxicological approaches for the quantitative inhalation risk assessment of toxic metals from tobacco smoke: application on the deterministic and probabilistic inhalation risk assessment of cadmium for Austrian smokers

OBJECTIVE

The objective of this study was the assessment of risks from inhalation exposure of Austrian smokers to cadmium through established toxicological approaches with emphasis on the exposure assessment component, which is challenging regarding the actual amount of metal that is inhaled and the simulation of the smoking pattern.

MATERIALS AND METHODS

Exposure assessment comprised an estimation of the proportion of cadmium inhaled through smoking and actual occurrence data in tobacco products and survey smoking habits, which were integrated in alternative scenarios through a deterministic and a probabilistic Monte Carlo simulation method. Risks were characterized through the comparison of the exposure with health-based guidance values, as well as through the assessment of the excess lifetime cancer risk (ELCR), the non-cancer hazard quotient (NCHQ), and the margin of exposure (MOE). The strengths, the uncertainties, and the limitations of the different methodologies were discussed.

RESULTS AND DISCUSSION

Upper exposures are close or exceed the Permitted Daily Exposure. Respiratory ELCRs are unacceptable compared to the benchmark range of 1.0E-06 to 1.0E-04. Renal and respiratory NCHQs exceed the target value of 1.0 by 3- to 17-fold. MOEs are not protective enough for cancer and non-cancer effects. The amount of cadmium that reaches the lung is a key source of uncertainty.

CONCLUSION

Probabilistic estimates provide a refined capture of the actual inhalation exposure. Risk estimates and gender and age profiles are alarming, especially for young smokers. Application of toxicological approaches, combined with realistic assessment of the inhalation exposure levels, can support risk communication and management.

A phosphorescence resonance energy transfer-based "off-on" long afterglow aptasensor for cadmium detection in food samples

Cadmium contamination is a severe food safety risk for human health. Herein, a long afterglow "off-on" phosphorescent aptasensor was developed based on phosphorescence resonance energy transfer (PRET) for the detection of Cd²⁺ in complex samples which minimizes the interference of background fluorescence. In this scheme, initially the phosphorescence of Cd²⁺-binding aptamer conjugated long afterglow nanoparticles (Zn₂GeO₄:Mn) was quenched by black hole quencher 1 (BHQ₁) modified complementary DNA. Upon encountering of Cd²⁺, the aptamer interacted with Cd²⁺ and the complementary DNA with BHQ₁ was released, leading to phosphorescence recovery. The content of Cd²⁺ could be quantified by the intensity of phosphorescence recovery with 100 μs gate time (which eliminated the sample autofluorescence) with a linear relationship between 0.5 and 50 μg L^-1 and a limit of detection (LOD) of 0.35 μg L^-1. This method was successfully demonstrated for Cd²⁺ detection in drinking water and yesso scallop samples. The "off-on" phosphorescent aptasensor based on PRET of long afterglow nanomaterials could be an effective tool for Cd²⁺ detection in food samples.

Metal biomarker mixtures and blood pressure in the United States: cross-sectional findings from the 1999-2006 National Health and Nutrition Examination Survey (NHANES)

BACKGROUND

The objective of this study was to identify conditional relationships between multiple metal biomarkers that predict systolic and diastolic blood pressure in the non-institutionalized United States adult population below the age of 60.

METHODS

We used inorganic exposure biomarker data and blood pressure data from three cycles (1999-2004) of the National Health and Nutrition Examination Survey (NHANES) to construct regression trees for blood pressure among adults ages 20-60 (adjusted for age, sex, body mass index, race, and smoking status) to identify predictors of systolic (SBP) and diastolic blood pressure (DBP). We also considered relationships among non-Hispanic black, Mexican-American, and white adults separately.

RESULTS

The following metal exposure biomarkers were conditionally predictive of SBP and/or DBP in the full sample: antimony (Sb), barium (Ba), cadmium (Cd), cesium (Cs), lead (Pb), tungsten (W) and molybdenum (Mo). The highest average SBP (> 120 mmHg) was observed among those with low Sb (≤ 0.21 μg/dL) high Cd (> 0.22 μg/g creatinine) and high Pb (> 2.55 μg/dL) biomarkers. Those with the highest average DBP had high urinary W levels (> 0.10 μg/g creatinine) in combination with either urinary Sb > 0.17 μg/g creatinine or those with urinary Sb ≤ 0.17 μg/g creatinine, but with high blood Pb levels (> 1.35 μg/dL). Predictors differed by ethnicity, with Cd as the main predictor of SBP among non-Hispanic black adults, and Pb not selected by the algorithm as a predictor of SBP among non-Hispanic white adults.

CONCLUSIONS

Combinations of metal biomarkers have different apparent relationships with blood pressure. Additional research in toxicological experimental models and in epidemiological studies is warranted to evaluate the suggested possible toxicological interactions between Sb, Cd, and Pb; and between W, Sb, and Pb; for cardiovascular (e.g., blood pressure) health. We also think future epidemiological research on inorganic exposure sets in relation to health outcomes like blood pressure might benefit from stratification by race and ethnicity.

Tobacco smoke is a likely source of lead and cadmium in settled house dust

INTRODUCTION

Environmental exposure to lead (Pb) and cadmium (Cd) are risk factors for adverse health outcomes in children and adults. This study examined whether thirdhand smoke residue contributes to Pb and Cd in settled house dust.

METHODS

Participants were 60 multiunit housing residents in San Diego, California. All had indoor smoking bans during the study period, and 55 were nonsmokers. Wipe samples from different surfaces and vacuum floor dust samples were analyzed for nicotine, a marker of thirdhand smoke, and for Pb and Cd using liquid chromatography-triple quadrupole mass spectrometry and inductively coupled plasma-mass spectrometry, respectively.

RESULTS

Examined in each sample type separately, Pb and Cd loadings were significantly correlated (r = 0.73, vacuum floor dust; 0.52, floor wipes; 0.72, window sill/trough wipes; all p < 0.0025). Pb and Cd loadings from different sample types were not correlated (all p > 0.30). Nicotine loading in dust was significantly correlated with Pb and Cd loading in dust (r = 0.49 for Pb; r = 0.39 for Cd, all p < 0.0025). Pb and Cd loadings on floor or window surfaces, showed no association with nicotine loading in dust, on floors, or on furniture (all p < 0.30).

CONCLUSIONS

Tobacco smoke is a likely source of Pb and Cd that accumulates in settled house dust in multiunit housing, suggesting that Pb and Cd are constituents of thirdhand smoke that lingers long after smoking has ended.

Association of Cigarette Smoking With Male Cognitive Impairment and Metal Ions in Cerebrospinal Fluid

Objective: Cigarette smoking might accelerate cognitive impairment; however, this has never been investigated using human cerebrospinal fluid (CSF). We conducted this study to investigate the association between cigarette smoking and cognitive impairment through metal ions in CSF. Methods: We obtained 5-ml CSF samples from routine lumbar puncture procedures in patients undergoing anterior cruciate ligament reconstruction before surgery in China. A total of 180 Chinese males were recruited (80 active smokers and 100 non-smokers). We measured specific cigarette-related neurotoxic metal ions in CSF, including iron, copper, zinc, lead, aluminum, and manganese. Sociodemographic data and history of smoking were obtained. The Montreal Cognitive Assessment (MoCA) was applied. Results: Active smokers had fewer years of education (11.83 ± 3.13 vs. 13.17 ± 2.60, p = 0.01), and higher age (33.70 ± 10.20 vs. 29.76 ± 9.58, p = 0.01) and body mass index (25.84 ± 3.52 vs. 24.98 ± 4.06, p =0.03) than non-smokers. Compared to non-smokers, active smokers had significantly higher CSF levels of iron, zinc, lead, and aluminum and lower MoCA scores (all p < 0.05). Average daily numbers of cigarettes smoked negatively correlated with the MoCA scores (r = -0.244, p = 0.048). In young smokers, CSF manganese levels negatively correlated with MoCA scores (r = -0.373, p = 0.009). Conclusions and Relevance: Cigarette smoking might be associated with male cognitive impairment, as shown by lower MoCA scores and higher levels of CSF iron, zinc, lead, and aluminum in active smokers. This might be early evidence of cigarette smoking accelerating male cognitive impairment.

Mercury in Pancreatic Cells of People with and without Pancreatic Cancer

Toxic metals have been implicated in the pathogenesis of pancreatic cancer. Human exposure to mercury is widespread, but it is not known how often mercury is present in the human pancreas and which cells might contain mercury. We therefore aimed to determine, in people with and without pancreatic cancer, the distribution and prevalence of mercury in pancreatic cells. Paraffin-embedded sections of normal pancreatic tissue were obtained from pancreatectomy samples of 45 people who had pancreatic adenocarcinoma, and from autopsy samples of 38 people without pancreatic cancer. Mercury was identified using two methods of elemental bio-imaging: (1) With autometallography, inorganic mercury was seen in islet cells in 14 of 30 males (47%) with pancreatic cancer compared to two of 17 males (12%) without pancreatic cancer (p = 0.024), and in 10 of 15 females (67%) with pancreatic cancer compared to four of 21 females (19%) without pancreatic cancer (p = 0.006). Autometallographic mercury was present in acinar cells in 24% and in periductal cells in 11% of people with pancreatic cancer, but not in those without pancreatic cancer. (2) Laser ablation-inductively coupled plasma-mass spectrometry confirmed the presence of mercury in islets that stained with autometallography and detected cadmium, lead, chromium, iron, nickel and aluminium in some samples. In conclusion, the genotoxic metal mercury is found in normal pancreatic cells in more people with, than without, pancreatic cancer. These findings support the hypothesis that toxic metals such as mercury contribute to the pathogenesis of pancreatic cancer.

Recent Advances in Speciation Analyses of Tobacco and Other Important Economic Crops

Background:

Speciation analysis is defined as the analytical activities of identifying and/or measuring the quantities of one or more individual chemical species in a sample. The knowledge of elemental species provides more complete information about mobility, bioavailability and the impact of elements on ecological systems or biological organisms. It is no longer sufficient to quantitate the total elemental content of samples to define toxicity or essentiality. Thus speciation analysis is of vital importance and generally offers a better understanding of a specific element.

Discussion:

Thorough speciation scheme consisting of sampling, sample preparation, species analysis and evaluation were described. Special emphasis is placed on recent speciation analysis approaches including both direct and coupling methods. A current summary of advantages and limitations of the various methods as well as an illustrative method comparison are presented. Certain elements and species of interest are briefly mentioned and practical examples of speciation applications in tobacco and other important economic crops are also discussed.

Aim/Conclusion:

This review aims to offer comprehensive knowledge about elemental speciation and provide readers with valuable information. Many strategies have been developed for the determination of multiple elemental species in tobacco and other important economic crops. Nevertheless, it is an eternal pursuit to establish speciation methods which can balance accuracy, agility as well as universality.

Cigarette-related cadmium and environmental pollution exposure are reflected in airway ultrafine particle content

Introduction

Particulate matter (PM) and cigarette-related cadmium exposure increases inflammation and smokers' susceptibility to developing lung diseases. The majority of inhaled metals are attached to the surface of ultrafine particles (UFPs). A low inhaled UFP content in exhaled breath condensate (EBC) reflects a high inflammatory status of airways.

Methods

EBC was collected from 58 COPD patients and 40 healthy smokers and nonsmokers. Participants underwent spirometry, diffusion capacity, EBC and blood sampling. Environmental pollution data were collected from monitoring stations. UFPs were measured in EBC and serum, and cadmium content was quantified.

Results

Subjects with low UFP concentrations in EBC (<0.18×10⁸·mL^-1) had been exposed to higher long-term PM_2.5 levels versus subjects with high UFP concentrations in EBC (>0.18×10⁸·mL^-1) (21.9 µg·m^-3 versus 17.4 µg·m^-3, p≤0.001). Long-term PM_2.5 exposure levels correlated negatively with UFP concentrations in EBC and positively with UFP concentrations in serum (r=-0.54, p≤0.001 and r=0.23, p=0.04, respectively). Healthy smokers had higher cadmium levels in EBC versus healthy nonsmokers and COPD patients (25.2 ppm versus 23.7 ppm and 23.3 ppm, p=0.02 and p=0.002, respectively). Subjects with low UFP concentrations in EBC also had low cadmium levels in EBC versus subjects with high UFP levels (22.8 ppm versus 24.2 ppm, p=0.004).

Conclusions

Low UFP concentration in EBC is an indicator of high-level PM exposure. High cadmium levels in EBC among smokers and the association between cadmium and UFP content in EBC among COPD patients indicate cadmium lung toxicity.

Metals and trace elements in relation to body mass index in a prospective study of US women

BACKGROUND

Epidemiologic studies on the association between metals and body mass index (BMI) have been cross-sectional and have demonstrated inconsistent associations. Our study prospectively examined whether metals measured at baseline were associated with later BMI. We considered metals individually and as joint exposure to pre-defined metal groupings.

METHODS

We measured concentrations of 16 metals in toenails collected at baseline (2003-2009) in a subset of 1221 women from the Sister Study. We calculated BMI from height and weight reported on a follow-up questionnaire an average of 5.2 years (range = 3.5-8.3) after baseline. Multivariable linear regression was used to estimate β coefficients and 95% confidence intervals (CIs) for associations between BMI and individual metals (with estimates given per interquartile range (IQR) increase or in quartiles). Quantile g-computation was used to examine joint associations between groups of metals and BMI. Groups considered were (1) all metals combined, and metals classified as (2) non-essential or (3) essential.

RESULTS

In individual metal models we found that, with the exception of cobalt, no single metal was strongly related to BMI. In our mixture analyses, a quartile increase in all non-essential metals was associated with higher BMI (β = 0.32; 95%CI: 0.00, 0.63 kg/m²), whereas essential metals were suggestively associated with lower BMI (β = -0.25; 95%CI: 0.58, 0.07 kg/m²).

CONCLUSIONS

In this population of women who were, on average, overweight, essential metals were jointly associated with slightly healthier, lower BMI whereas non-essential metals were jointly associated with slightly higher, unhealthier BMI, after controlling for other health indicators and predictors of metals exposures.

Cadmium and kidney function: Concentrations, variabilities, and associations across various stages of glomerular function

Data (N = 10336) from National Health and Nutrition Examination Survey for 2003-2016 for US adults aged ≥ 20 years were analyzed to evaluate the concentrations of blood and urine cadmium across the various stages of glomerular function. Estimated glomerular filtration rate (eGFR) > 90 mL/min/1.73 m² was defined to be glomerular function stage 1 (GF-1), eGFR between 60 and 90 mL/min/1.73 m² defined as GF-2, eGFR between 45 and 60 mL/min/1.73 m² as GF-3A, and eGFR between 15 and 45 mL/min/1.73 m² as GF-3B/4. Regression models stratified by GF-stages were fitted to estimate associations between the observed levels of blood and urine cadmium across stages of GF. Based on the results of stratified modes, there were consistent increases in adjusted geometric means (AGM_SM) for both blood and urine cadmium from GF-1 to GF-3A although increases were not uniform from one GF stage to another. For the total population, AGM_SM for blood and urine cadmium were GF-1 (0.47, 0.24), GF-2 (0.60, 0.37), GF-3A (0.72, 0.45), and GF-3B/4 (0.73, 0.45) μg/L. respectively. Although females had higher AGM_SMs than males for both blood and urine cadmium, the difference in blood cadmium narrowed as kidney function deteriorated. Smokers had the steepest increases in AGM_SMs for blood and urine cadmium across the stages of glomerular function and smoker-nonsmoker differences for blood cadmium narrowed as kidney function deteriorated but smoker-nonsmoker differences for urine cadmium widened as kidney function deteriorated. The important physiologic messages are that both blood and urine cadmium cease to increase from GF-3A to GF-3B/4, suggesting a new steady state based on renal failure. And, the narrowed difference in blood cadmium in smokers vs. nonsmokers suggests why this happens. Incremental exposures to cadmium are offset by excretion as renal failure progresses.

Smoking and other determinants of bone turnover

The balance between bone resorption and formation may be assessed by measurement of bone turnover markers (BTMs), like carboxyl-terminal cross-linked telopeptide of type 1 collagen (CTX-1) and procollagen type 1 amino-terminal propeptide (P1NP). Smoking has been shown to influence bone turnover and to reduce bone mass density (BMD), the exact mechanism for this is, however, not settled. In this post-hoc study including 406 subjects (mean age 51.9 years), we aimed to study the impact of smoking on bone turnover. Moreover, we wanted to assess the inter-correlation between substances regulating bone metabolism and BTMs, as well as tracking over time. BMD measurements and serum analyses of CTX-1, P1NP, osteoprotegerin (OPG), receptor activator of nuclear factor ĸB ligand (RANKL), Dickkopf-1 (DKK1), sclerostin, tumor necrosis factor-α (TNF-α), and leptin were performed. Repeated serum measurements were made in 195 subjects after four months. Adjustments were made for sex, age, body mass index (BMI), smoking status, insulin resistance, serum calcium, parathyroid hormone, 25-hydroxyvitamin D and creatinine. Smokers had higher levels of DKK1 and OPG, and lower levels of RANKL, as reflected in lower BTMs and BMD compared to non-smokers. There were strong and predominantly positive inter-correlations between BTMs and the other substances, and there was a high degree of tracking with Spearman’s rho from 0.72 to 0.92 (P < 0.001) between measurements four months apart. In conclusion, smokers exhibited higher levels of DKK1 and OPG and a lower bone turnover than did non-smokers. The strong inter-correlations between the serum parameters illustrate the coupling between bone resorption and formation and crosstalk between cells.

The Protective Impact of Black Chokeberry Fruit Extract (Aronia melanocarpa L.) on the Oxidoreductive System of the Parotid Gland of Rats Exposed to Cadmium

Cadmium (Cd) is a strongly toxic heavy metal with prooxidative properties. Since the exposure of the general population to this metal is predicted to increase, effective methods are being sought to prevent its negative actions. One of them involves the use of the antioxidant potential of polyphenol compounds contained in black chokeberry fruit extract and their capability of complex formation with Cd2+. The study objective was to investigate whether the administration of A. melanocarpa fruit extract rich in polyphenol compounds during low and moderate exposures to cadmium can protect the parotid gland against oxidative damage. The study was conducted using the experimental model on female Wistar rats which were given 0.1% aqueous extract of Aronia melanocarpa fruit (AE) and/or cadmium at a concentration of 1 (Cd1) or 5 (Cd5) mg Cd/kg feed for 3 and 10 months, and on control animals. The exposure to Cd attenuated the enzymatic antioxidant barrier (catalase (CAT), superoxide dismutase (SOD), glutathione peroxidase (GPx)) and increased the concentration of hydrogen peroxide (H2O2), protein carbonyl (PC) groups, and oxidized lipids (LPO) in parotid gland. These disorders led to a reduction in the total antioxidative status (TAS), an increase in the total oxidative state (TOS), and development of stress. The administration of AE at both levels of exposure to cadmium substantially improved the enzymatic antioxidant barrier (CAT, SOD, GPx) and prevented oxidative damage to cellular macromolecules (PC, LPO) and the increase in the level of H2O2, MPO, TOS, and stress indicator (OSI = TOS/TAS) in the parotid gland. Concluding, it should be stated that the consumption of aronia products may prevent oxidative/antioxidative imbalance induced by Cd and oxidative stress development in the parotid gland, thus protecting the gland from damage.

Mercury Exposure in Mother-Children Pairs in A Seafood Eating Population: Body Burden and Related Factors

Background: Mercury is a neurotoxin that affects neurodevelopment in children; however, its association at the lowest concentration is not clear. The main objective of this study is to measure and evaluate mercury concentrations in mother–child pairs and its association demographics, lifestyle, and dietary factors within the Pacific Island Families living in Auckland, New Zealand. Methods: Mercury exposure was assessed in a sub-sample of mother–child pairs who were a part of the Pacific Island Families birth cohort, in Auckland, New Zealand at the 6-year phase. Hair samples were collected from both mothers and their children to determine mercury concentrations. Total mercury was measured using inductively coupled plasma mass spectrometry for hair samples. An interviewer-based reliable food frequency questionnaire (FFQ) examined the frequency of seafood by all the participants. Other variables such as sociodemographic (ethnicity and gender), lifestyle factors (income, education, and smoking status) and health outcomes (child behaviour and obesity) were also collected. Results: In this study, 41% of both mothers and their children had mercury concentrations above the US Environmental Protection Agency (EPA) recommended value of 1 µg/g. Most of the participants ate fish 3 or more times a week. A significant correlation was observed between mother and child hair mercury concentrations (Spearman Rho 0.79 (95% confidence interval (CI): 0.65, 0.88)). Conclusions: Mercury levels in children can be affected by their mothers’ levels due to similar eating patterns.

Health Effects of Trace Metals in Electronic Cigarette Aerosols-a Systematic Review

Electronic cigarettes (ECs) are essentially nicotine delivery devices that mimic the appearance of a conventional cigarette (CC). Lately, they have been marketed as tools for quitting smoking. Even though they are promoted as safe alternatives to CC, they are not devoid of hazardous components. Literature reveals that the EC aerosols and e-liquids are a potential source of elements that induce and promote development of chronic conditions. These include trace metals which are leached from their core assembly. Some of these metals like nickel, chromium, cadmium, tin, aluminum, and lead are potential carcinogens. They have been associated with fatal conditions like lung and sinonasal cancer. Besides, they may have adverse effects on oral tissues like periodontal ligament and mucosa where they may trigger chronic periodontitis and oral cancer. However, there is only trivial evidence related to health hazards of metals released from ECs. With this background, the present review first focuses on the structure of the ECs followed by an appraisal of the data from experimental studies about the metals released in EC aerosols and their associated health hazards.

Determination of toxic and essential trace elements in serum of healthy and hypothyroid respondents by ICP-MS: A chemometric approach for discrimination of hypothyroidism

Inductively coupled plasma-mass spectrometry ((ICP-MS)) was used to determine three toxic (Ni, As, Cd) and six essential trace elements (Cr, Mn, Co, Cu, Zn, Se) in blood serum of patients with hypothyroidism (Hy group) and healthy people (control group), in order to set the experimental conditions for accurate determination of a unique profile of these elements in hypothyroidism. Method validation was performed with standard reference material of the serum by varying the sample treatment with both standard and collision mode for analysis of elements isotopes. Quadratic curvilinear functions with good performances of models and the lowest detection limits were obtained for ⁵²Cr, ⁶⁶Zn, ⁷⁵As, ¹¹²Cd in collision mode, and ⁵⁵Mn, ⁵⁹Co, ⁶⁰Ni, ⁶⁵Cu, ⁷⁸Se in standard mode. Treatment of serum samples with aqueous solution containing nitric acid, Triton X-100 and n-butanol gave the best results. Chemometric tools were applied for discrimination of patients with hypothyroidism. All nine elements discriminated Hy group of samples with almost the same discriminating power as indicated by their higher values for this group of patients. Statistically significant correlation (p < 0.01) was observed for several elements. Results indicated clear differences in element profile between Hy and control group and it could be used as a unique profile of hypothyroid state.

Multielemental Analysis of Tobacco Plant and Tobacco Products by TXRF

The aim of this research is to develop a fast analytical method for multielemental analysis of the tobacco plant Virginia tobacco (cultivated in Poland) and tobacco products (cigarettes, cigars, cigarillos, snuff and two kinds of properly crafted tobacco such as a shisha and cigarette tobacco) distributed in Polish markets by means of a low-power benchtop total reflection X-ray fluorescence (TXRF) system. For this purpose, a set of certified tobacco materials and real samples was employed. In leaves and stalks of V. tobacco and tobacco products, a concentration of 18 elements (P, S, Cl, K, Ca, Ti, Cr, Mn, Fe, Ni, Cu, Zn, As, Se, Br, Rb, Sr and Pb) was determined. Analyzing elemental composition of tobacco plants, one can see that concentrations of S, Ca, Ti, Mn, Zn, Sr and Pb are higher in leaves, whereas the concentrations of P, Cl, K, Fe Cu and Br are higher in stalks; the levels of Cr, Ni, As and Rb are comparable in both these parts of the tobacco plant. All of the parameters affecting sample preparation and TXRF measurements conditions were carefully evaluated. The accuracy and precision of the TXRF measurements were verified using an internal standardization approach for quantification.