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Updated: Jul 3, 2026
07:39
A Murine Pancreatic Islet Cell-based Screening for Diabetogenic Environmental Chemicals
Published on: June 25, 2018
Dioxin cancer risk--example of hormesis?
Jouko Tuomisto1, Juha Pekkanen, Hannu Kiviranta
1Department of Environmental Health, National Public Health Institute, Kuopio, Finland. jouko.tuomisto@ktl.fi
Summary
This study investigated dioxins and PCBs in relation to soft tissue sarcoma risk. Lower dioxin body burden was linked to higher sarcoma risk, suggesting a potential J-shaped curve.
Area of Science:
- Environmental Health
- Toxicology
- Oncology
Background:
- A prior study indicated an inverse correlation between dioxin body burden and soft tissue sarcoma (STS) risk.
- This unexpected finding prompted further investigation into related lipophilic compounds like polychlorinated biphenyls (PCBs).
Purpose of the Study:
- To examine the association between dioxin-like PCBs (PCB 77, 126, 169) and STS risk.
- To re-evaluate the relationship between dioxins and STS risk, considering potential PCB co-exposure.
Main Methods:
- Case-control study involving 110 STS patients and 227 appendicitis controls.
- Analysis of dioxin and PCB concentrations in subcutaneous fat using high-resolution gas chromatography-mass spectrometry.
- Calculation of WHO-Toxic Equivalent Concentrations (WHO-TEq) for dioxins and PCBs.
Main Results:
- The highest STS risk was observed in the lowest WHO-TEq body burden group.
- Statistically significant differences in risk were noted between the lowest group and groups with higher burdens (septiles 2 and 6).
- Similar J-shaped dose-response patterns were observed in animal studies.
Conclusions:
- The findings suggest a potential J-shaped dose-response curve for dioxins and STS risk, contrary to initial expectations.
- Further research is warranted to confirm these results, especially at higher exposure levels.
- The study highlights the complexity of chemical exposures and their impact on cancer risk.
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