Related Experiment Video
Updated: May 21, 2026

Micro-dissection of Enamel Organ from Mandibular Incisor of Rats Exposed to Environmental Toxicants
Published on: March 29, 2018
Low-dose fluoride and lead co-exposure alters bone mineral density in youth: A nationally representative
Chunxiang Li1, Zeyuan Niu1, Yuhui Du2
1Department of Occupational and Environmental Health, School of Public Health, Zhengzhou University, Zhengzhou, Henan 450001, PR China.
Purpose:
Both lead and fluoride can accumulate in the skeleton and cause skeletal damage; however, it remains unclear whether their co-exposure exacerbates the impacts on bone tissue. This study aims to investigate the relationship between co-exposure to fluoride and lead and changes in bone mineral density (BMD) among children and adolescents.
Methods:
Data were derived from 2378 participants in the National Health and Nutrition Examination Survey (2013-2016). Laboratory professionals measured the concentrations of plasma and water fluoride, whole blood and urine lead, BMD of the lumbar spine, pelvic, left and right legs. Linear regression, interaction and restricted cubic spline models were used to analyze the relationship between fluoride and lead exposure and BMD.
Results:
Plasma and water fluoride showed U-shaped associations with BMD, while blood and urinary lead demonstrated inverse nonlinear relationships with lumbar spine BMD-initially steep decline followed by an attenuated decrease (P-overall < 0.05, P-nonlinear < 0.05). Furthermore, the BMD of the pelvis and legs decreased as lead levels increased (P < 0.05). The interaction model of plasma fluoride and blood lead showed that, for every 1-unit increase in the interaction term, the BMD of the lumbar spine, left and right legs decreased by 1.679, 3.104, and 3.068 (P < 0.05), respectively.
Conclusions:
This study demonstrates that exposure to fluoride and lead is associated with changes in BMD among youth. Co-exposure to fluoride and lead exacerbates changes in BMD more than single exposure, suggesting synergistic effects on bone impairment.
Related Concept Videos
Essential Minerals for Bone Health
Calcium and Phosphorus
Calcium is a critical component of bones, especially in the form of calcium phosphate and calcium carbonate. Since the body cannot make calcium, it must be obtained from the diet. However, calcium cannot be absorbed from the small intestine without...
Bone Disorders
Bone deposition is also affected by the levels of sex hormones like estrogen and testosterone that promote osteoblast activity and bone matrix synthesis. When the level of these hormones decreases due to aging, it causes a reduction in bone deposition. As a result, bone resorption by osteoclasts...
Study Designs in Epidemiology
Observational studies are those where the researcher does not intervene but rather observes natural variations. They include cross-sectional, cohort, and case-control studies.
Minerals
Role of Vitamins in Maintaining Bone Health
Vitamin A
Vitamin A is involved in the process of bone remodeling. Retinoic acid, the active metabolite of Vitamin A, has nuclear receptors in osteoblasts and osteoclasts, which are involved in bone remodeling.
Vitamin B12
Vitamin B12 acts as a cofactor during the formation of osteoblast-related proteins, such as osteocalcin. Vitamin B12 plays a role...
Hormones and Bone Tissue
Hormones That Influence Osteoblasts and/or Maintain the Matrix
Several hormones are necessary for controlling bone growth and maintaining the bone matrix. The pituitary gland secretes growth hormone (GH), which, as its name implies, controls bone growth. This happens in several ways: first, it triggers chondrocyte...
