Predictors of erythrocyte cadmium levels in 454 adults in Florence, Italy

A comprehensive review on immobilized microbes - biochar and their environmental remediation: Mechanism, challenges and future perspectives

The environment worldwide has been contaminated by toxic pollutants and chemicals through anthropogenic activities, industrial growth, and urbanization. Microbial remediation is seen to be superior compared to conventional remediation due to its low cost, selectivity towards particular metal ions, and high efficiency. One key strategy in enhancing microbial remediation is employing an immobilization technique with biochar as a carrier. This review provides a comprehensive summary of sources and toxic health effects of hazardous water pollutants on human health and the environment. Biochar enhances the growth and proliferation of contaminant-degrading microbes. The combined activity of biochar and microbes in eliminating the contaminants has gained the researcher's interest. Biochar demonstrates its biocompatibility by fostering microbial populations, the release of enzymes, and protecting the microbes from the acute toxicity of surrounding contaminants. The current review complies with the immobilization technique and remediation mechanisms of microbes in pollutant removal. This review also emphasizes the combined utilization, environmental adaptability, and the potential of the combined effect of immobilized microbes and biochar in the remediation of contaminants. Challenges and future outlooks are urged to commercialize the immobilized microbes-biochar interaction mechanism for environmental remediation.

Does the environment affect menopause? A review of the effects of endocrine disrupting chemicals on menopause

Endocrine disrupting chemicals are widely distributed in our environment. Humans are exposed to these compounds not only through their occupations, but also through dietary consumption and exposure to contaminated water, personal care products and textiles. Chemicals that are persistent in the body and in our environment include dioxins and polychlorinated biphenyls. Non-persistent chemicals including bisphenol A, phthalates and parabens are equally as important because they are ubiquitous in our environment. Heavy metals, including lead and cadmium, can also have endocrine disrupting properties. Although difficult to study due to their variety of sources of exposures and mechanisms of action, these chemicals have been associated with early menopause, increased frequency of vasomotor symptoms, altered steroid hormone levels and markers of diminished ovarian reserve. Understanding the impacts of these exposures is important given the potential for epigenetic modification, which can alter gene function and result in multi-generational effects. This review summarizes findings in humans and animals or cell-based models from the past decade of research. Continued research is needed to assess the effects of mixtures of chemicals, chronic exposures and new compounds that are continuously being developed as replacements for toxic chemicals that are being phased out.

Serum heavy metals and breast cancer risk: A case-control study nested in the Florence cohort of the EPIC (European Prospective Investigation into Cancer and nutrition) study

BACKGROUND

Chronic exposure to heavy metals is of concern for its potential carcinogenic effect. An association with increased breast cancer (BC) risk was hypothesized, but literature data are conflicting and the question remains unresolved. We aimed to investigate the association between heavy metals and BC risk in a case-control study nested within the Florence section of the EPIC (European Prospective Investigation into Cancer and nutrition) cohort.

METHODS

We included 150 BC cases and an equal number of controls individually matched to cases by age and year of enrolment. In order to avoid confounding by smoking, the study was restricted to never smokers. Serum levels of six heavy metals (Cd, Co, Cr, Mn, Pb, and Tl) were quantified in pre-diagnostic samples using inductively coupled plasma mass spectrometry. Odds ratios (ORs) and corresponding 95 % confidence intervals (CI) were calculated via multivariable conditional logistic regression models.

RESULTS

Serum levels of cobalt were inversely associated with BC risk (OR for the comparison of 3rd vs. 1st tertiles: 0.33, 95 % CI 0.12-0.91, p-value 0.033). None of the other heavy metals under study was significantly associated with BC risk in multivariable models. For Cd, Cr, and Tl, over half of the study participants had serum levels below the limit of quantitation.

CONCLUSIONS

Our results do not support the hypothesis that exposure to heavy metals is associated with an increased BC risk among never smokers from the general population. The inverse association between cobalt serum levels and BC risk requires confirmation in future studies.

Bloodlettings in Hemochromatosis Result in Increased Blood Lead (Pb) Concentrations

Hemochromatosis is a hereditary disorder, most often associated with mutations of the HFE (High FErrum) gene. If left untreated, it can result in severe parenchymal iron accumulation. Bloodletting is the mainstay treatment. We have previously shown that treatment of hemochromatosis by repeated bloodlettings may induce changes in the serum levels of several trace elements. The aim of this work was to evaluate if whole blood concentrations of the environmental pollutants lead (Pb), mercury (Hg), and cadmium (Cd) could be affected by bloodlettings. We recruited 28 patients and 21 healthy individuals (control group). Whole blood and urine levels of Pb, Hg, and Cd were measured before the start and after the completion of treatment using inductively coupled plasma mass spectrometry, together with serum iron and liver function tests. Concentrations of blood Pb, but not Hg or Cd, were significantly increased after treatment. The increase in Pb was higher in C282Y homozygous patients than in the other patients, and it was positively correlated with the serum concentration of alkaline phosphatase. Bloodlettings in hemochromatosis result in an increase in the blood concentration of Pb. Augmented absorption due to iron loss or Pb mobilization from bone may contribute to the higher blood Pb level.

Levels and determinants of urinary cadmium in general population in Spain: Metal-MCC-Spain study

BACKGROUND

Cadmium is a ubiquitous and persistent metal, associated with different harmful health effects and with increased morbidity and mortality. Understanding the main sources of exposure is essential to identify at risk populations and to design public health interventions.

OBJECTIVE

To evaluate cadmium exposure in a random-sample of general adult population from three regions of Spain, assessed by the urinary cadmium (U-Cd) concentration, and to identify its potential determinants and sex-specific differences, including sociodemographic, lifestyle and dietary factors.

MATERIALS AND METHODS

We measured U-Cd (μg/g creatinine) in single urine spot samples from 1282 controls enrolled in the multicase-control study in common tumors in Spain (MCC-Spain) with inductively coupling plasma-mass spectrometry equipped with an octopole reaction systems (ICP-ORS-MS). The association between sociodemographic, lifestyle, and dietary characteristics and U-Cd concentrations was evaluated using geometric mean ratios (GMR) estimated by multiple log-linear regression models.

RESULTS

Overall, geometric mean U-Cd concentration was 0.40 (95%CI: 0.38, 0.41) μg/g creatinine. Levels were higher in women than in men (GMR]: 1.19; 95%CI: 1.07, 1.32), and increased with age in males (p_trend< 0.001). Cigarette smoking was clearly associated to U-Cd levels (GMR_{former vs non-smokers}: 1.16; 95%CI: 1.05, 1.29; GMR_{current vs non-smokers}: 1.42; 95%CI: 1.26, 1.60); the relationship with secondhand tobacco exposure in non-smokers, was restricted to women (p_interaction = 0.02). Sampling season and region also seemed to influence U-Cd concentrations, with lower levels in summer (GMR_{summer vs average}: 0.79; 95%CI: 0.71, 0.88), and higher levels in North-Spain Asturias (GMR_{Asturias vs average}: 1.13; 95%CI: 1.04, 1.23). Regarding diet, higher U-Cd concentration was associated with eggs consumption only in men (p_interaction = 0.04), just as rice intake was associated in women (p_interaction = 0.03).

CONCLUSION

These results confirmed that tobacco exposure is the main modifiable predictor of U-Cd concentrations, and remark that the role of dietary/sociodemographic factors on U-Cd levels may differ by sex.

Cadmium and lipid balance in outdoor workers exposed to urban stressor

The aim of our study was to evaluate the association between levels of blood and urinary cadmium and lipid balance in a group of outdoor workers. The study was conducted on a group of 146 individuals (average age 45,1 ± 8,5). Blood and urinary samples were collected for the detection of total cholesterol, HDL cholesterol, LDL cholesterol, triglycerides, blood cadmium and urinary cadmium. We divided the group of workers into two subgroups according to the task:75 traffic policemen and 71 police drivers. Gender differences were found. The Pearson correlation coefficient showed a positive association between blood and urinary cadmium levels and total cholesterol, LDL and triglycerides levels. Total cholesterol, LDL cholesterol and triglycerides were significantly higher in the group of traffic policemen than in police drivers. In conclusion, the results suggest a statistically significant association between blood and urinary cadmium levels and lipid balance contributing to an increase of the cardiovascular risk.

Relationship between ambient PM2.5 exposure and blood cadmium level in children under 14 years in Beijing, China

Ambient PM_2.5 pollution is a global environmental problem. PM_2.5 can act as a carrier of heavy metals. However, the relationship between PM_2.5 exposure and blood cadmium (Cd) level in children was less understood. Based on the data of hourly collected PM_2.5 and blood Cd level of 13,626 children aged 0-14 years from Apr. 2008 to Feb. 2013 in Beijing of China, we investigated the short-term effects of PM_2.5 exposure on blood Cd level. Generalized linear mixed models (GLMMs) were utilized to explore the potential association between PM_2.5 exposure and blood Cd level of children. The results showed that the mean blood Cd level was 0.64 μg/L. There was a significant association between PM_2.5 exposure and blood Cd level (P < 0.05). Age was negatively associated with blood Cd level (P < 0.05), and the younger children were more sensitive to Cd from PM_2.5 exposure. There wasn't a significant difference in PM_2.5 concentration between heating and non-heating seasons in winter (P > 0.05); there was also no gender difference of children on blood Cd level (P > 0.05). The present study demonstrates the importance of controlling the PM_2.5 bound Cd exposure, and environmental countermeasures should be implemented stringently to reduce their impact on children's health.

Effects of lead and cadmium on the immune system and cancer progression

In our daily life, we are surrounded by harmful pollutants, including heavy metals that are not visible in the macroscopic view easily. Heavy metals can disrupt different aspects of human health, such as the immune system which has gained a lot of attention in recent decades. This had led to its rapid progression and new insights into its alterations in different diseases especially cancer. Heavy metals are non-biodegradable materials that exist in different parts of the food cycle, such as fruits and vegetables as commonly consumed foods and also unexpected sources such as street dust, that exists in the streets that we pass every day, soil, air, and water. These heavy metals can enter the human body through respiratory, cutaneous, and gastrointestinal pathways and then accumulate in different organs, leading to their encountering with various parts of the body. These sources and natural characteristics of heavy metals facilitate their interaction with the immune system. In this review, we investigated the effect of lead and cadmium, as pollutants that exist in many different parts of the human environment, on the immune system which is known to have a key role in the pathophysiology of cancer.

Cadmium toxicity: effects on human reproduction and fertility

Background Cadmium (Cd) is a non-essential toxic heavy metal, an environmental toxicant, and toxic at a low concentration, and it has no known beneficial role in the human body. Its exposure induces various health impairments including hostile reproductive health. Objective The present review discusses the information on exposure to Cd and human reproductive health impairments including pregnancy or its outcome with respect to environmental and occupational exposure. Methods The present review provides current information on the reproductive toxic potential of Cd in humans. The data were collected using various websites and consulting books, reports, etc. We have included recent data which were published from 2000 onward in this review. Results Cd exposure affects human male reproductive organs/system and deteriorates spermatogenesis, semen quality especially sperm motility and hormonal synthesis/release. Based on experimental and human studies, it also impairs female reproduction and reproductive hormonal balance and affects menstrual cycles. Based on the literature, it might be concluded that exposure to Cd at low doses has adverse effects on both human male and female reproduction and affects pregnancy or its outcome. Further, maternal prenatal Cd exposure might have a differential effect on male and female offspring especially affecting more female offspring. Hence, efforts must be made to prevent exposure to Cd. Conclusion Cd affects both male and female reproduction, impairs hormone synthesis/regulation and deteriorates pregnancy rate or its outcome even at lower doses.

Determinants of Erythrocyte Lead Levels in 454 Adults in Florence, Italy

Background: Lead exposure, even at low levels, is associated with adverse health effects in humans. We investigated the determinants of individual lead levels in a general population-based sample of adults from Florence, Italy. Methods: Erythrocyte lead levels were measured (using inductively coupled plasma-mass spectrometry) in 454 subjects enrolled in the Florence cohort of the European Prospective Investigation into Cancer and Nutrition (EPIC) study in 1992⁻1998. Multiple linear regression models were used to study the association between demographics, education and working history, lifestyle, dietary habits, anthropometry, residential history, and (among women) menstrual and reproductive history and use of exogenous sex hormones, and erythrocyte lead levels. Results: Median lead levels were 86.1 μg/L (inter-quartile range 65.5⁻111.9 μg/L). Male gender, older age, cigarette smoking and number of pack-years, alcohol intake, and residing in urban areas were positively associated with higher erythrocyte lead levels, while performing professional/managerial or administrative work or being retired was inversely associated with lead levels. Among women, lead levels were higher for those already in menopause, and lower among those who ever used hormone replacement therapy. Conclusions: Avoidable risk factors contribute to the lead body burden among adults, which could therefore be lowered through targeted public health measures.

Association between dietary cadmium intake and early gastric cancer risk in a Korean population: a case-control study

PURPOSE

Foods such as grains and vegetables are the dominant sources of exposure to cadmium, which has been classified as a carcinogen by various public health agencies. Cadmium exposure is a growing concern due to its associations with numerous harmful health effects, including gastric cancer risk. The objective of this study was to investigate the association of dietary cadmium intake and the consumption of cadmium-contributing foods with early gastric cancer risk.

METHODS

A case-control study including 1245 subjects (cases, 415; controls, 830) was conducted in Korea. The dietary cadmium intake and the consumption of cadmium-contributing foods were assessed using a semi-quantitative food frequency questionnaire.

RESULTS

After adjustment for covariates, the gastric cancer risk was increased for participants in the highest tertile of cadmium intake [odds ratios (ORs) 1.33, 95% confidence intervals (95% CIs) 0.94-1.88], but there was no significance. Both female (ORs 2.71, 95% CIs 1.37-5.36) and male (ORs 1.63, 95% CIs 1.07-2.50) participants in the highest tertile of rice consumption had a higher gastric cancer risk than did those in the lowest tertile. Men in the highest tertile of crab consumption had a gastric cancer risk 2.23 times greater than that of men in the lowest tertile (ORs 2.23, 95% CIs 1.21-4.13), but a difference was not seen in women.

CONCLUSIONS

Future studies examining the causal effects of dietary cadmium intake and the consumption of cadmium-contributing foods on early gastric cancer risk in large-scale prospective cohorts are recommended.