Association between environmental toxic metals, arsenic and polycyclic aromatic hydrocarbons and chronic obstructive pulmonary disease in the US adult population

Comprehensive analysis of environmental exposure to hazardous trace elements and lung function: a national cross-sectional study

BACKGROUND

There is growing interest in the joint effects of hazardous trace elements (HTEs) on lung function deficits, but the data are limited. This is a critical research gap given increased global industrialisation.

METHODS

A national cross-sectional study including spirometry was performed among 2112 adults across 11 provinces in China between 2020 and 2021. A total of 27 HTEs were quantified from urine samples. Generalised linear models and quantile-based g-computation were used to explore the individual and joint effects of urinary HTEs on lung function, respectively.

RESULTS

Overall, there were negative associations between forced expiratory volume in 1 s (FEV1) and urinary arsenic (As) (z-score coefficient, -0.150; 95% CI, -0.262 to -0.038 per 1 ln-unit increase), barium (Ba) (-0.148, 95% CI: -0.258 to -0.039), cadmium (Cd) (-0.132, 95% CI: -0.236 to -0.028), thallium (Tl) (-0.137, 95% CI: -0.257 to -0.018), strontium (Sr) (-0.147, 95% CI: -0.273 to -0.022) and lead (Pb) (-0.121, 95% CI: -0.219 to -0.023). Similar results were observed for forced vital capacity (FVC) with urinary As, Ba and Pb and FEV1/FVC with titanium (Ti), As, Sr, Cd, Tl and Pb. We found borderline associations between the ln-quartile of joint HTEs and decreased FEV1 (-20 mL, 95% CI: -48 to +8) and FVC (-14 mL, 95% CI: -49 to+2). Ba and Ti were assigned the largest negative weights for FEV1 and FVC within the model, respectively.

CONCLUSION

Our study investigating a wide range of HTEs in a highly polluted setting suggests that higher urinary HTE concentrations are associated with lower lung function, especially for emerging Ti and Ba, which need to be monitored or regulated to improve lung health.

The association between cadmium exposure and the risk of chronic obstructive pulmonary disease: A systematic review and meta-analysis

According to the World Health Organization, chronic obstructive pulmonary disease (COPD) was one of the top ten causes of death worldwide in 2019. The ratio of forced expiratory volume in the first second to forced vital capacity (FEV1/FVC) provides a useful indicator for the diagnosis of COPD. Existing data have demonstrated that cadmium (Cd) exposure is associated with COPD. However, data concerning the incidence and progression of cadmium-induced COPD is inconsistent. To explore the relationship between cadmium exposure and the risk of COPD in humans, through January 12, 2023, we conducted a thorough search of the PubMed, Cochrane, Web of Science, Embase and Scopus databases for relevant material. In this study, a meta-analysis was conducted to evaluate the association between cadmium and COPD. This meta-analysis indicated that exposure to cadmium (per 1 μg/L increase) was associated with reduced FEV1/FVC (% change = -47.54%, 95% CI: -54.99% to -40.09%). Subgroup analysis showed that the combined effect estimates were significantly higher in the COPD patient group (% change = -54.66%, 95% CI: -83.32% to -26.00%) than in the general population (% change = -52.11%, 95%CI: -60.53% to -43.70%). Therefore, we conclude that cadmium exposure is associated with reduced FEV1/FVC, which suggests a risk for COPD.

Association between carotenoids and the prevalence of chronic obstructive pulmonary disease in the United States

BACKGROUND

Previous studies mainly concentrated on examining the correlation between single carotenoids and Chronic obstructive pulmonary disease (COPD). However, these findings have been inconsistent.

OBJECTIVES

This study aimed to evaluate both the individual and overall associations of carotenoids with the prevalence of COPD.

METHODS

This study comprised 2,939 participants chosen from the National Health and Nutrition Examination Survey (NHANES) 2017-2018. The logistic regression, quantile-based G-computation regression (qgcomp), and Bayesian kernel machine regression (BKMR) models were employed to explore the association between carotenoids and the prevalence of COPD. Mediation analyses were also conducted to explore the underlying mechanism of carotenoids on COPD.

RESULTS

Individuals diagnosed with COPD had significantly lower serum carotenoid concentrations than those without COPD. We found a negative relationship between combined carotenoids and the prevalence of COPD, and lutein and zeaxanthin and alpha cryptoxanthin were identified as the main contributors to this negative association. Moreover, eosinophil acted as a mediator in the relationship between lutein and zeaxanthin, alpha cryptoxanthin, and the prevalence of COPD, with mediating proportions of 2.75 % and 3.67 %.

CONCLUSION

A negative association was observed between combined carotenoids and COPD prevalence, with lutein and zeaxanthin, and alpha cryptoxanthin identified as the main contributors. Eosinophils could potentially mediate the association between carotenoids and COPD.

Arsenic effectively improves the degradation of fluorene by Rhodococcus sp. 2021 under the combined pollution of arsenic and fluorene

The performance of bacterial strains in executing degradative functions under the coexistence of heavy metals/heavy metal-like elements and organic contaminants is understudied. In this study, we isolated a fluorene-degrading bacterium, highly arsenic-resistant, designated as strain 2021, from contaminated soil at the abandoned site of an old coking plant. It was identified as a member of the genus Rhodococcus sp. strain 2021 exhibited efficient fluorene-degrading ability under optimal conditions of 400 mg/L fluorene, 30 °C, pH 7.0, and 250 mg/L trivalent arsenic. It was noted that the addition of arsenic could promote the growth of strain 2021 and improve the degradation of fluorene - a phenomenon that has not been described yet. The results further indicated that strain 2021 can oxidize As3+ to As5+; here, approximately 13.1% of As3+ was converted to As5+ after aerobic cultivation for 8 days at 30 °C. The addition of arsenic could greatly up-regulate the expression of arsR/A/B/C/D and pcaG/H gene clusters involved in arsenic resistance and aromatic hydrocarbon degradation; it also aided in maintaining the continuously high expression of cstA that codes for carbon starvation protein and prmA/B that codes for monooxygenase. These results suggest that strain 2021 holds great potential for the bioremediation of environments contaminated by a combination of arsenic and polycyclic aromatic hydrocarbons. This study provides new insights into the interactions among microbes, as well as inorganic and organic pollutants.

Role of Metals on SARS-CoV-2 Infection: a Review of Recent Epidemiological Studies

PURPOSE OF REVIEW

Metals and metalloids are known for their nutritional as well as toxic effects in humans. In the context of the SARS-CoV-2 pandemic, understanding the role of metals on COVID-19 infection is becoming important due to their role in infectious diseases. During the past 2 years, a significant number of studies have examined the impact of metals and metalloids on COVID-19 morbidity and mortality. We conducted a systematic review of peer-reviewed manuscripts on the association of metals and metalloids with SARS-CoV-2 infection and COVID-19 severity published since the onset of the pandemic.

RECENT FINDINGS

We searched for epidemiological studies available through the PubMed database published from January 2020 to December 2022. Of 92 studies identified, 20 met our inclusion criteria. These articles investigated the association of zinc (Zn), iron (Fe), selenium (Se), manganese (Mn), cadmium (Cd), arsenic (As), copper (Cu), magnesium (Mg), chromium (Cr), and/or lead (Pb) levels on SARS-CoV-2 infection and/or COVID-19 severity. Of the ten metals and metalloids of interest that reported either positive, negative, or no associations, Zn yielded the highest number of articles (n = 13), followed by epidemiological studies on Se (n = 7) and Fe (n = 5). Elevated serum Zn and Se were associated with reduced COVID-19 severity and mortality. Similarly, higher levels of serum Fe were associated with lower levels of cellular damage and symptoms of SARS-CoV-2 infection and with faster recovery from COVID-19. On the other hand, higher serum and urinary Cu and serum Mg levels were associated with higher COVID-19 severity and mortality. Along with the positive or negative effects, some studies reported no impact of metals on SARS-CoV-2 infection. This systematic review suggests that metals, particularly Zn, Fe, and Se, may help reduce the severity of COVID-19, while Cu and Mg may aggravate it. Our review suggests that future pandemic mitigation strategies may evaluate the role of Zn, Se, and Fe as potential therapeutic interventions.

Association of urinary arsenic, polycyclic aromatic hydrocarbons, and metals with cancers among the female population in the US

BACKGROUND

Cancers that primarily affect women in the US include breast, uterine, and cervical cancers. There may be associations between these different types of cancer in women and environmental pollutant exposure.

PURPOSE

This study aimed to assess seven species of arsenic, six polycyclic aromatic hydrocarbon (PAH) compounds, and fourteen different metal concentrations in urine and their correlation with cancer among women.

METHODS

We conducted a cross-sectional analysis using 2011--2012 to 2015-2016 National Health and Nutrition Examination Survey data (n = 4,956) and logistic regression modeling of the complex weighted survey design.

RESULTS

Breast cancer was inversely correlated with arsenocholine (3rd quantile), monomethylarsonic acid (4th quantile), manganese (4th quantile), and antimony (3rd, 4th quantiles). Cervical cancer was inversely correlated with 3-hydroxyfluorene (3rd quantile), molybdenum (2nd, 4th quantiles), antimony (3rd quantile), tin (4th quantile), and thallium (4th quantile) exposure and positively associated with arsenic acid (3rd quantile), arsenobetaine (2nd, 4th quantiles). Uterine cancer was correlated with 1-hydroxynaphthalene (3rd, 4th quantiles), 2-hydroxynaphthalene (4th quantile), 1-hydroxyphenathrene (2nd, 4th quantiles), 1-hydroxypyrene (3rd quantile), cobalt (2nd, 3rd quantiles) and inversely with mercury (4th quantile).

CONCLUSION

This study determined breast cancer and arsenic and some metal species exposure, indicating an inverse association. Arsenic acid and arsenobetaine exposure showed a positive correlation with cervical cancer. For uterine cancer, the correlations for the PAH compounds and cobalt showed a positive correlation, and the arsenic species and mercury were inversely associated. Further research is required to establish or refute the findings.

Exposure to polycyclic aromatic hydrocarbons increases the risk of poor sleep pattern in US adults: results from the NHANES (2005-2010)

Recently, polycyclic aromatic hydrocarbons (PAHs) were found to be linked to various diseases. The current study's objective was to explore whether or not there was a relation between PAH exposure and poor sleep pattern. We evaluated nine urine PAH metabolites as exposures in our cross-sectional research based on the National Health and Nutrition Examination Survey (NHANES) from 2005 to 2010. Logistic regression, restricted cubic spline regression (RCS) model, weighted quantile sum (WQS) regression, subgroup analysis, and mediation analysis were used to assess the associations between PAH metabolism and poor sleep pattern risk. After controlling for all confounding variables, several primary PAH metabolites, namely 1-hydroxynapthalene (1-NAP, OR 1.32, 95% CI 1.04-1.68), 2-hydroxyfluorene (2-FLU, OR 1.34, 95% CI 1.05-1.71), 1-hydroxyphenanthrene (1-PHE, OR 1.30, 95% CI 1.03-1.64), 9-hydroxyfluorene (9-FLU, OR 1.38, 95% CI 1.09-1.74), and ∑PAHs (OR 1.33, 95% CI 1.05-1.69), compared to the bottom tertile, were associated with increased risk of poor sleep pattern. The WQS regression analysis showed that 9-FLU and 1-NAP comprised the two most important factors related to poor sleep pattern. Mediation analysis revealed that inflammation acted as a mediator between PAHs and the prevalence of poor sleep pattern. In conclusion, exposure to PAHs may be associated with poor sleep pattern. Inflammation is a mediator of the effects of PAH exposure on poor sleep pattern.

Industrial impact on sustainable dairy farms: Essential elements, hazardous metals and polycyclic aromatic hydrocarbons in forage and cow's milk

Sustainable dairy farms are characterised by the self-production of forage for animal feed. These farms are sometimes located near industrial areas, entailing a risk of food chain contamination with hazardous metals and polycyclic aromatic hydrocarbons (PAHs). Accordingly, evaluating the impact of pollution on forage and milk is of great interest. In this study, the effects of industrial factors on sustainable forage from 43 dairy farms and possible correlations between inorganic elements and PAHs were studied. Spearman's correlation and principal component analysis (PCA) were performed for the forage and milk. Most of the inorganic elements in the forage were below the maximum residual limits for cadmium (Cd) and lead (Pb), established in EU 2013/1275 and EU 2019/1869, respectively. However, arsenic (As) and mercury (Hg) levels were above their respective limits in the forage (EU 2019/1869). No milk samples exceeded the maximum residual limits for Pb (EU 488/2014) or Cd (EU 1881/2006) in dairy products. Heavy-weight PAHs (HW-PAHs, four or more aromatic rings) were detected in forage but not in milk. In the forage samples, HW-PAHs were positively correlated with Zn and Cd. In addition, some hazardous metals (chromium (Cr), iron (Fe), As, Hg, and Pb) also were positively correlated with Zn and Cd. Interestingly, no correlations were found between forage pollutants and milk, suggesting that these pollutants have a low transfer rate to milk. The PCA results highlighted the predominant contribution of PAHs to the global variance in forage samples collected at different distances from industrial areas. In milk, the contributions of hazardous metals and PAHs were more balanced than in forages. Finally, when distances to potential pollution sources were included in the PCA of forage samples, a negative correlation was observed between the former and the concentrations of HW-PAHs, Cd, and Zn, suggesting that thermal power plants and steel factory emissions were the main sources of polluting forage in this area.

Exposure to arsenic, polycyclic aromatic hydrocarbons, metals, and association with skin cancers in the US adults

Worldwide, skin cancer affects millions of people yearly and is broadly classified into melanoma and nonmelanoma types of skin cancer. The toxicity of metals to human health is a public and clinical health problem due to their widespread use in tools, machinery, and appliances as well as their widespread distribution in the air, water, and soil. Arsenic is a carcinogenic metalloid and available in the Earth's crust. Polycyclic aromatic hydrocarbons (PAHs) are toxic to humans, and incomplete combustion of fossil fuels is the main source of PAHs. Human populations exposed to metals from various sources can lead to various diseases including cancer. Limited studies are conducted to simultaneously assess the correlation of multiple arsenic, PAHs, metals with the occurrence of skin cancer. This study aimed to analyze the association between six PAHs compounds, seven types of arsenic, and fourteen metals from urine specimen with skin cancer in US adults. We performed a cross-sectional analysis using data from a total of 14,716 adults from the National Health Examination and Nutrition Survey (NHANES) database for three cycles ranging from 2011-2012 to 2015-2016. Specialized weighted complex survey logit regressions were conducted. Linear logit regression models using only main effects were performed first to identify the correlation between the selected demographic and lifestyle variables and melanoma, nonmelanoma, and unknown types of skin cancer. A second set of linear, main-effects logit regression models were constructed to examine the correlation between melanoma, nonmelanoma, and other types of skin cancers and seven types of arsenic (arsenous acid, arsenic acid, arsenobetaine, arsenocholine, dimethylarsinic acid, monomethylacrsonic acid, and total arsenic), six PAHs (1-hydroxynaphthalene, 2-hydroxynaphthalene, 3-hydroxyfluorene, 2-hydroxyfluorene, 1-hydroxyphenathrene, and 1-hydroxypyrene), and fourteen metals (barium, cadmium, cobalt, cesium, molybdenum, manganese, lead, antimony, tin, strontium, thallium, tungsten, uranium, and mercury) when adjusted for the selected covariates. The statistical analysis was conducted using R software, version 4.0.4. A marginal positive significant correlation between total arsenic and nonmelanoma was observed. This study identified a significant positive association between barium, cadmium, cesium, mercury, tin, and melanoma development. Cesium showed a significant positive statistical association for nonmelanoma, and thallium showed a borderline significant statistical association for nonmelanoma. A statistically significant positive association was found between cadmium and an unknown type of skin cancer. The findings of this study indicated a statistically significant positive association between skin cancer and barium, cadmium, cesium, tin, mercury, and thallium. Further studies are recommended in humans to refute or confirm these findings.

Arsenic, polycyclic aromatic hydrocarbons, and metal exposure and risk assessment of stroke

Globally, stroke is one of the primary causes of morbidity and mortality. In the USA, stroke is a major cause of death and disability. Limited studies assessed the impact of polycyclic aromatic hydrocarbons, arsenic, and other metal exposure and their association with the risk of stroke. This study aimed to assess different arsenic species, including total arsenic; two types of organic arsenic, i.e., arsenobetaine and arsenocholine; four types of inorganic arsenic, i.e., arsenic acid, arsenous acid, dimethylarsinic acid (DMA), and monomethylarsonic acid (MMA); six types of urinary polycyclic aromatic hydrocarbon (PAH) compounds, i.e., 1-hydroxynaphthalene, 1-hydroxyphenanthrene, 1-hydroxypyrene, 2-hydroxynaphthalene, 2-hydroxyfluorene, and 3-hydroxyfluorene; and fourteen types of metals from urine specimen, i.e., manganese, cadmium, lead, mercury, barium, cobalt, strontium, molybdenum, cesium, thallium, antimony, tin, tungsten, and uranium and their association with those who reported having been told they had had a stroke by a medical professional. The National Health and Nutrition Examination Survey (NHANES) data used in this study include three data cycles from 2011-2016. In this study, data from a total of 5537 males and females who are aged 20 years and older were analyzed using logistic modeling of the complex weighted survey design. R version 3.6.3 software was used to conduct the analyses. Four species of urinary PAHs, including the third quantiles of 1-hydroxynaphthalene [odds ratio (OR): 2.327, 95% confidence interval (CI): 0.961-5.632], 2-hydroxynaphthalene [OR: 2.449, 95% CI: 1.067-5.622], and 3-hydroxyfluorene [OR: 2.289, 95% CI: 1.077-4.861] and the second quantiles of 3-hydroxyfluorene [OR: 2.201, 95% CI: 1.115, 4.346] and 1-hydroxypyrene [OR: 2.066, 95% CI: 1.037, 4.114], showed a positive correlation with increased odds of stroke. Among metals, the third (3rd) [OR: 3.566, 95% CI: 1.370, 9.280] and fourth (4th) [OR: 2.844, 95% CI: 0.947, 8.543] quantiles of urinary manganese showed a positive correlation with increased odds of stroke.

Prevalence of associated factors on depression during COVID 19 in students in a minority serving institution: A cross sectional study

Introduction

The COVID-19 pandemic changed the learning style of university students in the US, affecting their mental health of students. This study aims to understand the factors that influenced depression during the COVID-19 pandemic in the New Mexico State University (NMSU) student population.

Methods

A questionnaire assessing mental health and lifestyle factors was delivered to NMSU students by using Qualtrics^XM software. Depression was assessed using the Patient Health Questionnaire- 9 (PHQ-9); depression was defined as a score ≥10. Single and multifactor logistic regression was performed using R software.

Results

This study determined that the prevalence of depression among female students was 72% and 56.30% among male students. Several covariates were significant for increased odds of depression in students, including decreased diet quality (OR: 5.126, 95% CI: 3.186-8.338), annual household income $10,000 - $20,000 (OR: 3.161, 95% CI: 1.444-7.423), increased alcohol consumption (OR: 2.362, 95% CI: 1.504-3.787), increased smoking (OR: 3.581, 95% CI:1.671-8.911), quarantining due to COVID (OR: 2.001, 95% CI: 1.348-2.976), and family member dying of COVID (OR: 1.916, 95% CI: 1.072-3.623). Covariates of being male (OR: 0.501, 95% CI: 0.324-0.776), married (OR: 0.499, 95% CI: 0.318-0.786), eating a balanced diet (OR: 0.472, 95% CI: 0.316-0.705), and sleeping 7-8 h per night (OR: 0.271, 95% CI: 0.175-0.417) were all protective factors for depression in NMSU students.

Limitation

This is a cross-sectional study, and therefore, causation cannot be determined.

Conclusion

Several factors regarding demographics, lifestyle, living arrangements, alcohol and tobacco use, sleeping behavior, family vaccination, and COVID status were significantly associated with depression in students during the COVID-19 pandemic.

Association between co-exposure of polycyclic aromatic hydrocarbons and chronic obstructive pulmonary disease among the US adults: results from the 2013-2016 National Health and Nutrition Examination Survey

Although existing epidemiological studies have reported the relationship between single polycyclic aromatic hydrocarbon (PAH) exposure and chronic obstructive pulmonary disease (COPD), little is known about the impact of PAH mixture exposure on COPD. Therefore, we aimed to evaluate the associations of single and mixed exposures to PAHs with COPD in US adults using data from NHANES 2013-2016 by fitting three statistical methods, including multiple logistic regression, Bayesian kernel machine regression (BKMR), and quantile-based g-computation (qgcomp) models. This study included 1836 participants aged 40 and older. Multiple logistic regression showed that 2-FLU, 1-PHE, 1-PYR, and 2&3-PHE increased the risk of COPD after adjusting for all covariates. The BKMR model identified positive trends between PAH mixture and the risk of COPD in all adults and males when all PAHs were at or above their 55th percentile compared to all PAHs at their 50th percentile. The qgcomp model suggested that PAH co-exposure increased the risk of COPD (OR:1.44, 95%CI:1.09, 1.90) when each quartile increased in PAH mixture concentration, with 2-FLU having the highest weight. The combined impact also be observed in men. In conclusion, PAHs co-exposure was associated with a higher risk of COPD, especially in males, with the positive impact of 2-FLU being the most important.

Polycyclic aromatic hydrocarbon exposure burden: Individual and mixture analyses of associations with chronic obstructive pulmonary disease risk

Accumulating data demonstrate that polycyclic aromatic hydrocarbons (PAH) exposure is linked to compromised respiratory diseases. This study aimed to analyze urinary PAH metabolites and their associations with chronic obstructive pulmonary disease (COPD) in a sample size of 3015 subjects from a total population of 50,588 from the National Health and Nutrition Examination Survey (NHANES) in 2007-2016. Results showed that the most predominant metabolite was 1-Hydroxynaphthalene (1-NAP, 84%) with a geometric mean concentration of 50,265 ng/L, followed by its homologue 2-NAP (10%), both of which arose from sources including road emission, smoking and cooking. Multiple logistic regression showed that seven of the ten major PAH metabolites were correlated with increased COPD risk: including 1-NAP (OR: 1.83, 95%CI: 1.25, 2.69), 2-Hydroxyfluorene (2-FLU, OR: 2.29, 95%CI: 1.42, 3.68) and 1-Hydroxyphenanthrene (1-PHE, OR: 2.79, 95%CI: 1.85, 4.21), when compared to the lowest tertile after adjusted for covariates. Total exposure burden per PAH congener sub-group demonstrated persistent positive correlation with COPD for ∑PHE (OR: 1.80, 95%CI: 1.34, 2.43) and ∑FLU (OR: 2.74, 95%CI: 1.77, 4.23) after adjusted for covariates. To address the contribution of PAH exposure as mixture towards COPD, weighted quantile sum (WQS) regression analyses revealed that 1-NAP, 9-Hydroxyfluorene (9-FLU), 3-Hydroxyfluorene (3-FLU) and 1-PHE were among the top contributors in the associations with COPD. Our results demonstrate the contemporary yet ongoing exposure burden of PAH exposure for over a decade, particularly towards NAPs and FLUs that contribute significantly to COPD risk, calling for more timely environmental regulation.

Association between asthma, chronic bronchitis, emphysema, chronic obstructive pulmonary disease, and lung cancer in the US population

Lung cancer is one of the primary causes of death with poor life expectancy after diagnosis. History of past respiratory diseases such as asthma, chronic obstructive lung disease (COPD), emphysema, and chronic bronchitis can increase the risk of lung cancer. Very few studies are available to simultaneously assess multiple respiratory diseases and lung cancer. The objective of this study was to investigate correlations between asthma, emphysema, chronic bronchitis, and chronic obstructive lung disease with lung cancer in the US adult population. This was a cross-sectional study using data from a total of 23,523 adult participants from the National Health Examination and Nutrition Survey (NHANES) datasets for seven cycles ranging from 2003-2004 to 2015-2016. To analyze the data, specialized weighted complex survey logit regressions were conducted. Linear logit regression models using only main-effects were constructed first to assess the correlation between the selected demographic and lifestyle variables and asthma, emphysema, chronic bronchitis, and COPD. A second set of linear, main-effects logit regression models were constructed to examine the correlation between lung cancer and asthma, emphysema, chronic bronchitis, COPD when corrected for the selected covariates. The study identified positive correlations between emphysema, chronic bronchitis, COPD, and lung cancer. No correlation between asthma and lung cancer was established. Of the covariates studied, race/ethnicity, marital status, highest educational level, age, family income to poverty ratio, and lifetime smoking were also found to be correlated with the presence of lung cancer. Correlations between the covariates gender, body mass index, alcohol consumption, and country of birth and lung cancer were not found. The study established statistically significant correlations between lung cancer and the lung diseases emphysema, chronic bronchitis, and COPD. The lack of association between asthma and lung cancer may arise from the timeline of diagnosis asthma or type of lung cancer. The study also established significant correlations between lung cancer and several of the covariates included in the analysis. It also established correlations between the covariates and the lung diseases asthma, emphysema, chronic bronchitis, and COPD.

Acute arsenic exposure exacerbates lipopolysaccharide-induced lung injury possibly by compromising the integrity of the lung epithelial barrier in rats

Inhalation of large amounts of arsenic can damage the respiratory tract and may exacerbate the development of bacterial pneumonia, but the exact mechanism remains unclear. In this study, male Wistar rats were randomly divided into control, arsenic trioxide (16.0 μg/kg ATO), lipopolysaccharide (0.5 mg/kg LPS), and ATO combined with LPS (16.0 μg/kg ATO + 0.5 mg/kg LPS) groups. Blood and lung tissue samples were collected from each group 12 h after exposure. The results showed that exposure to ATO or LPS alone produced different effects on leukocytes and inflammatory factors, while combined exposure significantly increased serum interleukin-6, interleukin-10, lung water content, lung lavage fluid protein, and p38 protein phosphorylation levels. Alveolar interstitial thickening, alveolar membrane edema, alveolar type I and II cell matrix vacuolization, and nuclear pyknosis were observed in rats exposed to either ATO or LPS. More severe ultrastructural changes were found in the combined exposure group, and chromatin splitting was observed in alveolar type I cells. Lanthanum nitrate particles leaked from the alveolar vascular lumen in the ATO-exposed group, whereas in the combined exposure group, Evans Blue levels were increased and lanthanum nitrate particles were present in the lung parenchyma. Claudin-3 protein expression increased and claudin-4 expression decreased after ATO or LPS exposure, while claudin-18 expression was unchanged. The changes in claudin-3 and claudin-4 protein expression were further exacerbated by combined exposure. In conclusion, these results suggest that inhalation of ATO may exacerbate the development of bacterial pneumonia and that common mechanisms may exist to synergistically disrupt epithelial barrier integrity.

The mechanism of the cadmium-induced toxicity and cellular response in the liver

Cadmium is a toxic element to which man can be exposed at work or in the environment. Cd's most salient toxicological property is its exceptionally long half-life in the human body. Once absorbed, Cd accumulates in the human body, particularly in the liver. The cellular actions of Cd are extensively documented, but the molecular mechanisms underlying these actions are still not resolved. The liver manages the cadmium to eliminate it by a diverse mechanism of action. Still, many cellular and physiological responses are executed in the task, leading to worse liver damage, ranging from steatosis, steatohepatitis, and eventually hepatocellular carcinoma. The progression of cadmium-induced liver damage is complex, and it is well-known the cellular response that depends on the time in which the metal is present, ranging from oxidative stress, apoptosis, adipogenesis, and failures in autophagy. In the present work, we aim to present a review of the current knowledge of cadmium toxicity and the cellular response in the liver.