[Correlations between HBCD and thyroid hormone concentrations in human serum from production source area]

Area of Science:

• Environmental Chemistry
• Toxicology
• Human Health Risk Assessment

Background:

• Hexabromocyclododecane (HBCD) is a brominated flame retardant with widespread environmental presence.
• Human exposure to HBCD is a growing concern, particularly in regions with HBCD production.
• Understanding the health implications of HBCD exposure is crucial for public health.

Purpose of the Study:

• To quantify HBCD levels in human serum from an HBCD production source region.
• To investigate the relationship between HBCD exposure and thyroid hormone abnormalities.
• To assess the potential health risks associated with HBCD in the exposed population.

Main Methods:

• Analysis of HBCD isomers (α-HBCD, γ-HBCD) in human serum using Ultra-Performance Liquid Chromatography-Electrospray Ionization-Tandem Mass Spectrometry (UPLC-ESI-MS/MS).
• Quantification of ∑ HBCD concentrations based on lipid weight in 80 serum samples.
• Statistical analysis to compare HBCD levels and thyroid hormone abnormality rates across demographic groups.

Main Results:

• Detected ∑ HBCD concentrations in serum ranged from not detectable to 2702.5 ng·g⁻¹ (lipid weight), with mean and median values of 104.9 ng·g⁻¹ and 5.9 ng·g⁻¹, respectively.
• γ-HBCD was the most abundant isomer in 42 samples, and α-HBCD in 26 samples.
• A significant association was found between the presence of HBCD in serum and a higher rate of thyroid hormone abnormalities (up to 33% in the study population).

Conclusions:

• Residents in HBCD production regions exhibit significant serum HBCD contamination.
• HBCD exposure is strongly associated with an increased probability of thyroid hormone abnormalities.
• Urgent measures are needed to mitigate HBCD exposure and protect public health in affected communities.