Perfluoroalkyl substances in human bone: concentrations in bones and effects on bone cell differentiation

Area of Science:

• Environmental Science
• Toxicology
• Bone Biology

Background:

• Per- and polyfluoroalkyl substances (PFAS) are persistent environmental pollutants with known toxicological effects.
• Previous research indicated PFAS distribution in mouse bone and bone marrow.
• The presence and impact of PFAS on human bone tissue require further investigation.

Purpose of the Study:

• To investigate PFAS levels in human femoral bone samples.
• To explore the relationship between PFAS and human bone microarchitecture.
• To examine the effects of perfluorooctanoic acid (PFOA) on human osteoblast and osteoclast differentiation.

Main Methods:

• Analysis of PFAS concentrations in human femoral bone and bone marrow samples (n=18).
• PFAS analysis in soft tissue and bone biopsies from a human cadaver.
• In vitro studies on human osteoblasts and osteoclasts exposed to PFOA.

Main Results:

• PFAS, notably perfluorooctane sulfonate (PFOS) and PFOA, were detected in human dry bone and bone marrow.
• Highest PFAS concentrations were found in cadaver lung and liver tissues; bone marrow was PFAS-free.
• Perfluorononanoic acid (PFNA) was detected in bone, while PFOA and PFOS were absent.
• In vitro, PFOA did not affect osteogenic differentiation but increased osteoclast resorption at lower concentrations, with resorption ceasing at higher concentrations.

Conclusions:

• PFAS are present in human bone tissue.
• PFAS can impact human bone cells, specifically osteoclasts, at environmentally relevant concentrations.
• Further research is needed to fully understand the implications of PFAS on bone health.