The periodontal health of lead-exposed children living in a shipyard industrial area

Association of individual and combined exposures of 10 metals with periodontitis: Results from a large population-based study

AIMS

To systematically investigate the association between individual and combined metal exposure and periodontitis.

METHODS

Data encompassing complete periodontal examinations and metal detection in blood and urine samples were procured from the National Health and Nutrition Examination Survey (NHANES) 2011-2014. Three statistical methods, namely weighted logistic regression, Bayesian kernel machine regression (BKMR), and weighted quantile sum (WQS) regression, were used to evaluate the independent and combined associations between metals and periodontitis.

RESULTS

Elevated concentrations of blood cadmium (odds ratio [OR]: 1.73, 95% confidence interval [CI]: 1.15-2.61) and blood lead (OR: 1.17, 95 %CI: 1.02-1.34) exhibited a positive association with periodontitis, even after adjusting for potential confounding factors. The BKMR and WQS regression suggested that the co-exposure of metals was also positively associated with periodontitis. Moreover, estradiol and albumin were identified as potential mediators in the relationship between the WQS index of the 10 metals in blood and periodontitis explaining 25.36% and 2.02% of the relationship, respectively. Furthermore, generally consistent patterns of associations between metals and periodontitis and mediating roles of estrogen and albumin were observed after a series of sensitivity analyses.

CONCLUSION

This study provides evidence of positive associations between elevated levels of cadmium, lead or metal mixture and periodontitis, which may be partially mediated by sex hormones and oxidative stress indicators.

Association between levels of blood trace minerals and periodontitis among United States adults

Aim

Evidence linking trace minerals and periodontitis is limited. To investigate the relationship between trace minerals (selenium, manganese, lead, cadmium, and mercury) and periodontitis, data from the National Health and Nutrition Examination Survey (NHANES) were analyzed after accounting for potential confounding factors. No known studies have explored the relationship between these five trace minerals and periodontitis.

Materials and methods

A total of 4,964 participants who had undergone a full-mouth periodontal examination and laboratory tests for five trace minerals were studied in a cross-sectional study. Clinical attachment loss (CAL) and periodontitis grading were used to measure periodontitis severity. Linear and logistic regression models were used to evaluate the association between trace minerals and periodontitis. Further subgroup analyses were performed.

Results

Blood lead and cadmium levels were positively associated with mean CAL, and blood selenium was negatively associated with mean CAL; however, blood mercury, blood manganese, and mean CAL were not significantly associated. The association between trace minerals and mean CAL was more significant in males, the elderly, and patients with diabetes. There was a threshold effect between blood cadmium levels and mean CAL. Among the Black population, the relationship between blood cadmium levels and mean CAL followed an inverted U-shaped curve. There was a saturation effect in the study of blood lead in people aged 45–59 years old.

Conclusion

Our study highlighted that blood selenium, lead, and cadmium levels were significantly associated with periodontitis in a nationally representative sample of United States adults.

Role of lead in dental diseases

Lead (Pb) is ubiquitous in our environment and causes many pathophysiological health effects, including dental diseases. Dental Pb levels are considered good biological indicators of environmental and occupational Pb exposure. Pb in blood and saliva causes imbalances in the growth of oral microflora. The pH of saliva decreases, interferes with and interacts with bone-seeking elements, changes oral inflammatory parameters, generates reactive oxygen species, causes oxidative damage, and delays the mineralization process, leading to dental diseases. Pb's dental diseases include periodontitis, enamel lesions and defects, fluorosis, Burton's line, and tooth loss. Environmental and physiological factors, including age, gender, tooth type and position, pregnancy and lactation, eating and drinking habits, smoking habits, and exposures from Pb-contaminated residential and occupational areas, affect the distribution of Pb in blood, bone, and saliva, which contributes to dental diseases. However, living and working in Pb free areas can prevent environmental and occupational Pb exposure. Healthy lifestyles and eating habits, prohibiting smoking and alcohol drinking, further help prevent Pb exposure. Also, the fluoridation of water, salt, and milk provide nutritional supplements of trace elements, which can help prevent teeth from absorbing Pb from the environment, thereby reducing the risk of dental diseases.

Children's Environmental Health in Thailand: Past, Present, and Future

Background:

There is increasing evidence of a link between environmental pollution and preventable diseases in developing countries, including Thailand. Economic development has generated several types of pollution that can affect population health. While these environmental health effects can be observed throughout life, pregnant women and children represent particularly vulnerable and sensitive groups.

Methods:

The published epidemiological literature investigating environmental chemical exposure in Thai children was reviewed, highlighting those that investigated associations between exposure and subsequent health outcomes.

Results:

The majority of the Thai epidemiological studies on environmental health in children were cross-sectional in design, with some demonstrating associations between exposure and outcome. The three main types of chemical exposure in Thai children were pesticides, heavy metals, and air pollution, which resulted from agricultural activities in countryside areas, industrial zones (both registered and unregistered establishments), mining, and traffic in inner cities. Major health outcomes included detrimental effects on cognitive function and cancer risk. Pesticide exposure was focused on, but not limited to, agricultural areas. The success of the Thai environmental policy to introduce lead–free petrol can be demonstrated by the decline of mean blood lead levels in children, particularly in urban areas. However, unregistered lead-related factories and smelters act as hidden sources. In addition, there is increasing concern, but little acknowledgement, about the effects of chronic arsenic exposure related to mining. Lastly, air pollution remains a problem in both dense city populations due to traffic and in rural areas due to contamination of indoor air and house dust with heavy metals, endotoxins and other allergens.

Conclusions:

The increasing number of published articles demonstrates an improved awareness of children’s environmental health in Thailand. Chemical hazards, including the improper use of pesticides, environmental contamination with heavy metals (lead and arsenic), and air pollution in inner cities and indoor air, continue to be growing issues.

Lead exposure may affect gingival health in children

Background

Several studies have reported the harmful effects of lead poisoning. However, the relationship between lead exposure and oral health of children has not been well defined. The aim of this study was to investigate the relationship between blood lead level (BLL) and oral health status of children.

Methods

A total of 351 children (aged 7–15 years) were recruited from the pilot data of the Korean Environmental Health Survey in Children and Adolescents, which was designed to examine environmental exposure and children’s health status in South Korea. Blood samples were taken to determine BLLs and oral examinations were performed to assess oral health parameters, including community periodontal index (CPI), gingival index (GI), and plaque index (PI). Information regarding socioeconomic status, oral hygiene behavior, and dietary habits was collected from parents and guardians.

Results

The participants were divided equally into four quartiles, with quartile I comprised of children with the lowest BLLs. There were significant differences for PI (p < 0.05) among the quartile groups. Using logistic regression models, we found a significant relationship between BLL and oral health parameters. The crude odds ratios for CPI, GI, and PI in the third quartile were 5.24 (95% CI: 1.48-18.56), 4.35 (95% CI: 1.36-13.9), and 4.17 (95% CI: 1.50-11.54), respectively, while the age and gender-adjusted odds ratios were 7.66 (95% CI: 1.84-31.91), 6.80 (95% CI: 1.80-25.68), and 3.41 (95% CI: 1.12-10.40), respectively. After adjustments for age, gender, parent education level, and frequency of tooth brushing, the adjusted odds ratios were 7.21 (95% CI: 1.72-30.19), 6.13 (95% CI: 1.62-23.19), and 3.37 (95% CI: 1.10-10.34), respectively.

Conclusions

A high BLL might be associated with oral health problems in children, including plaque deposition and gingival diseases.