Heavy metal exposure, in combination with physical activity and aging, is related with oxidative stress in Japanese women from a rural agricultural community

Distribution of urinary trace element exposure and dietary sources in women over 50 in an agricultural region- A community-based KoGES cohort study

BACKGROUND

There is a noticeable lack of information on the levels of both non-essential and essential trace elements in women aged over 50. The main objective of this study is to investigate trace element concentrations and explore the influence of sociodemographic factors and dietary sources of exposure in this demographic.

METHODS

We analyzed 19 trace elements, including manganese, cobalt, copper, zinc, molybdenum, chromium, nickel, arsenic, strontium, cadmium, tin, antimony, cesium, barium, tungsten, mercury, thallium, lead, and uranium, using ICP-MS and mercury analyzer. Urine samples were obtained from a cohort of 851 women aged over 50 who participated in the 8th KoGES-Ansung study (2017-2018). Multiple linear models were employed to explore associations between urinary trace element concentrations and sociodemographic factors and dietary sources of exposure. We used K-means clustering to discern patterns of exposure to trace elements and identify contributing factors and sources.

RESULTS

Our findings indicate higher concentrations of molybdenum (Mo), arsenic (As), cadmium (Cd), and lead (Pb) in our study population compared to women in previous studies. The study population were clustered into two distinct groups, characterized by lower or higher urinary concentrations. Significant correlations between age and urinary concentrations were observed in Ni. Smoking exhibited positive associations with urinary Cd and As. Associations with dietary sources of trace elements were more distinct in women in the high-exposure group. Urinary antimony (Sb) was positively linked to mushroom and egg intake, As to mushroom and fish, and Hg to egg, dairy products, fish, seaweed, and shellfish.

CONCLUSIONS

Our study underscores the significant gap in understanding urinary concentrations of trace elements in women aged over 50. With higher concentrations of certain elements compared to previous studies and significant correlations between age, smoking, and specific food sources, it is imperative to address this gap through targeted dietary source-specific risk management.

Oxidative damage associated with exposure to heavy metals present in topsoils in central Chile

Exposure to heavy metals may cause the overproduction of reactive oxygen species, generating oxidative stress and consequently, various harms to human health. The soil surrounding the Ventanas Industrial Complex, in Puchuncaví and Quintero municipal districts on the central Chilean coast, contains heavy metal concentrations (As, Cu, Pb, Zn, among others) that far exceed the maximum permissible levels established by Italian soil standards (used as a reference). This study aimed to investigate the potential association between heavy metal exposure in humans and the levels of oxidative stress biomarkers in inhabitants of these locations. We took blood samples from 140 adults living in sites with high concentrations of heavy metals in the soil and compared them with blood samples from 140 adults living in areas with normal heavy metal concentrations. We assessed lipid peroxidation, damage to genetic material, and Total Antioxidant Capacity in these blood samples. Our results indicate an association between oxidative damage and heavy metal exposure, where the inhabitants living in exposed areas have a higher level of DNA damage compared with those living in control areas. Given that DNA damage is one of the main factors in carcinogenesis, these results are of interest, both for public health and for public policies aimed at limiting human exposure to environmental pollution.

Impact of modernization on oxidative stress among indigenous populations in northern Laos

OBJECTIVES

To explore the impact of modernization on oxidative stress during a momentous health transition process, we investigated differences in oxidative stress among the indigenous populations of villages in northern Laos with different levels of modernization.

METHODS

We conducted a cross-sectional study of 380 adults in three villages with different levels of modernization. Three biomarkers related to oxidative stress were measured: urinary 8-hydroxy-2'-deoxyguanosine (8-OHdG) and 8-isoprostane concentrations (both measured by liquid chromatography-tandem mass spectrometry), and blood telomere length (measured with qPCR). We examined associations between village-level modernization and oxidative stress-related biomarkers in a multilevel analysis including a random effect and covariates.

RESULTS

The geometric means of urinary 8-OHdG and 8-isoprostane concentrations were 2.92 and 0.700 μg/g creatinine, respectively, in our study population. Higher urinary 8-OHdG concentrations and shorter telomeres were observed in participants from the more modernized villages, whereas urinary 8-isoprostane concentrations did not differ significantly among villages.

CONCLUSIONS

Our findings imply that modernization-induced changes in lifestyle may increase oxidative DNA damage. Baseline levels of oxidative lipid damage are expected to be high in the indigenous populations of northern Laos. Assessments of oxidative stress may provide valuable insights into the mechanisms of health transition in specific populations.

Genotoxic Effects of Lead and Their Impact on the Expression of DNA Repair Genes

Exposure to lead (Pb) continues to be a significant worldwide problem. Pb is a highly poisonous heavy metal affecting several organ systems in the body. Although Pb has been shown to be genotoxic to experimental animals and humans, the underlying mechanisms are still not understood. An indirect mechanism related to the inhibition of DNA repair systems by Pb has been suggested. Heavy metals can interfere with the activities of several proteins and gene expressions. Recent studies gathered in this review article demonstrated an altered expression of DNA repair genes due to Pb toxicity. However, their findings are conflicting. Furthermore, the interaction of Pb and epigenetic mechanisms regulating gene expression may have a crucial role in the inhibition of DNA repair systems. Therefore, additional studies are needed to evaluate these findings and to obtain a complete picture of the genotoxic properties of Pb and the underlying mechanisms that may have a crucial role in carcinogenesis.

Evaluation of DNA Damage and Expressions of DNA Repair Gene in Occupationally Lead Exposed Workers (Jodhpur, India)

Occupational exposure to lead (Pb) remains a significant concern for worker's health working in different factories. There are many discrepancies among the results regarding the studies of genotoxicity of Pb. The present study aimed to evaluate DNA damage and expressions of DNA repair genes (OGG1, XRCC1, and XPD) in occupationally Pb-exposed workers of Jodhpur, India. The study consisted of 100 occupationally Pb-exposed workers and 100 controls (non-exposed) with no history of occupational exposure. Pb levels were determined by atomic absorption spectrophotometry, serum 8-hydroxy-2-deoxyguanosine (8-OHdG) concentrations were measured by ELISA, and expressions of DNA repair genes (OGG1, XRCC1, and XPD) were estimated by RT-PCR. The results indicated significantly higher levels of Pb in the exposed group as compared with the non-exposed group (p < 0.0001). Serum 8-OHdG concentrations were significantly higher (p < 0.0083), and all three DNA repair genes were significantly downregulated (fold change: OGG1, 0.188; XRCC1, 0.125; XPD, 0.133) in the Pb-exposed group as compared with the non-exposed. In conclusion, the study findings suggest that Pb exposure is associated with increased DNA damage and reduced DNA repair capacity, which may lead to serious health issues in occupationally Pb-exposed workers.

Association between blood lead exposure and mental health in pregnant women: Results from the Japan environment and children's study

OBJECTIVE

Although environmental lead exposure has decreased, several studies have shown that low-level lead exposure can result in adverse psychological symptoms. However, few studies have examined lead neurotoxicity in pregnant women. We investigated the association between lead exposure and psychological symptoms in pregnant women, and between socio-economic status and blood lead levels.

METHODS

Blood lead levels were measured in 17,267 pregnant women in the Japan Environment and Children's Study. Odds ratios (ORs) for high blood lead levels were calculated using multinomial logistic regression. Psychological symptoms were assessed using the Kessler Psychological Distress Scale (K6). ORs for depression (K6 ≥ 13 or ≥5) were calculated using logistic regression with adjustment for potential confounders.

RESULTS

The geometric mean of whole blood lead levels was 0.58 μg/dl (range 0.14-6.75 μg/dl). Higher blood lead levels were associated with older age (OR 1.79, 9 5% confidence interval [CI] 1.46-2.19), unmarried status (OR 1.75, 95 % CI 1.31-2.33), lower household income (OR 1.76, 95 % CI 1.38-2.24), and lower educational attainment (OR 1.34, 95 % CI 1.20-1.48). The percentage of women with K6 scores ≥13 and ≥5 was 3 % and 28.2 %, respectively. There was no significant association between lead exposure and K6 score (K6 ≥ 13: OR 1.00, 95 % CI 0.76-1.32; K6 ≥ 5: OR 0.98, 95 % CI 0.88-1.09).

CONCLUSION

Our results indicate a small but significant association between higher blood lead levels and lower socio-economic status in a population with low blood lead levels, but no association between low-level lead exposure and psychological symptoms.

Health Problems Among Workers Who Recycle Electronic Waste in Southern Thailand

Objectives

This study evaluated the prevalence of adverse health effects among recycling facility workers, and described their socioeconomic situation, health symptoms and work characteristics.

Methods

A cross-sectional study was conducted by interviewing 71 workers in 20 electronic waste (e-waste) recycling facilities in southern Thailand. Data were collected by questionnaire. Risk factors were evaluated using multiple logistic regression analysis.

Results

Recycling facility workers with blurred vision were significantly associated with being male (p = 0.035), over 40 years old (p = 0.020), and having ≤ secondary school education (p = 0.017). Rash/itching was associated with being male (p = 0.011), over 40 years (p = 0.018), having ≤ secondary school education (p = 0.012). not using a cloth mask (p = 0.019), not using gloves (p = 0.028), not washing hands before lunch (p = 0.005), not cleaning clothes daily (p = 0.025), and not having established ventilation systems in the place of work (p = 0.018). Hand-and-feet numbness were associated with being male (p = 0.025), and being over 40 years (p = 0.023). Headaches were associated with being male (p = 0.028).

Conclusion

Personal hygiene is important for this occupational group, and it should be emphasized in education programs.

Smoking modify the effects of polycyclic aromatic hydrocarbons exposure on oxidative damage to DNA in coke oven workers

PURPOSE

Coke oven emissions containing polycyclic aromatic hydrocarbons (PAHs) are predominant toxic constituents of particulate air pollution that have been linked to increased risk of lung cancer. Numerous epidemiological studies have suggested that oxidative DNA damage may play a pivotal role in the carcinogenic mechanism of lung cancer. Little is known about the effect of interaction between PAHs exposure and lifestyle on DNA oxidative damage.

METHODS

The study population is composed by coke oven workers (365) and water treatment workers (144), and their urinary levels of four PAH metabolites and 8-hydroxydeoxyguanosine (8-OHdG) were determined. Airborne samples of exposed sites (4) and control sites (3) were collected, and eight carcinogenic PAHs were detected by high-performance liquid chromatography.

RESULTS

The median values of the sum of eight carcinogenic PAHs and BaP in exposed sites were significantly higher than control sites (P < 0.01). The study found that the urinary PAH metabolites were significantly elevated in coke oven workers (P < 0.01). Multivariate logistic regression analysis revealed that the risk of high levels of urinary 8-OHdG will increase with increasing age, cigarette consumption, and levels of urinary 1-hydroxypyrene, and P for trend were all <0.05. Smoking can significantly modify the effects of urinary 1-hydroxypyrene on high concentrations urinary 8-OHdG, during co-exposure to both light or heavy smoking and high 1-hydroxypyrene levels (OR 4.28, 95% CI 1.32-13.86 and OR 5.05, 95% CI 1.63-15.67, respectively).

CONCLUSIONS

Our findings quantitatively demonstrate that workers exposed to coke oven fumes and smoking will cause more serious DNA oxidative damage.