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Temporal environmental hysteresis: A definition and implications for polybrominated diphenyl ethers
Ronald A Hites1, Daniel C Lehman1, Amina Salamova1
1O'Neill School of Public and Environmental Affairs, Indiana University, Bloomington, IN 47405, United States of America.
The Science of the Total Environment
|November 19, 2020
Summary
Environmental hysteresis causes a time lag in pollutant decline after use stops. This study shows polybrominated diphenyl ethers (PBDEs) exhibit this phenomenon, with concentrations persisting for years after market withdrawal.
Area of Science:
- Environmental Chemistry
- Atmospheric Science
- Toxicology
Background:
- Polybrominated diphenyl ethers (PBDEs) were widely used flame retardants in consumer products.
- PBDEs were phased out of the North American market in 2004 (Penta-BDE, Octa-BDE) and 2013 (Deca-BDE).
- Understanding the environmental persistence of PBDEs is crucial for assessing long-term risks.
Purpose of the Study:
- To define and investigate "temporal environmental hysteresis" for PBDEs.
- To quantify the time lag between PBDE market withdrawal and concentration decline in the atmosphere.
- To analyze atmospheric PBDE concentrations at urban sites in Chicago and Cleveland.
Main Methods:
- Analysis of approximately 700 atmospheric samples collected bi-weekly from 2005 to 2018.
- Focus on specific PBDE congeners: BDE-47, BDE-99, and BDE-209.
- Statistical analysis to determine the rate of concentration change and associated uncertainties.
Main Results:
- In Chicago, BDE-47 and BDE-99 half-lives were 5.9 ± 0.9 and 8.0 ± 1.4 years, respectively.
- In Chicago, BDE-209 concentrations doubled every 7.6 ± 1.8 years.
- In Cleveland, BDE-47 and BDE-99 half-lives were 5.1 ± 0.4 and 5.7 ± 0.5 years, respectively; BDE-209 half-life was 9.2 ± 1.6 years.
Conclusions:
- PBDEs exhibit significant temporal environmental hysteresis, with atmospheric concentrations persisting long after market withdrawal.
- The observed delays in concentration decline highlight the decadal-scale persistence of these flame retardants.
- Findings underscore the importance of considering environmental hysteresis in risk assessment and management of persistent pollutants.
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