Skip Navigation

Final Progress Reports: University of Iowa: Assessment of Toxicity and Risk of Inhaled Environmental PCB Mixtures

Superfund Research Program

Assessment of Toxicity and Risk of Inhaled Environmental PCB Mixtures

Project Leader: Peter S. Thorne
Grant Number: P42ES013661
Funding Period: 2015-2020
View this project in the NIH Research Portfolio Online Reporting Tools (RePORT)

Project-Specific Links

Connect with the Grant Recipients

Visit the grantee's eNewsletter page Visit the grantee's eNewsletter page Visit the grantee's Twitter page

Final Progress Reports

Year:   2019 

The researchers are investigating adverse outcome pathways associated with in vivo inhalation of complex mixtures of polychlorinated biphenyls (PCBs) to gain insights on how molecular and cellular processes affect immune, neurologic, and developmental systems. In the last year, project researchers completed a 13-week chronic inhalation study to the School Air Mixture with added non-legacy PCBs (SAM+), a simulated PCB profile found in the indoor air of several East Chicago schools attended by participants enrolled in the Airborne Exposures to Semi-volatile Organic Pollutants (AESOP Study) Project. A wide array of adverse health outcomes that were measured focused on general health status (weight gain, body condition), organ histopathology, cytotoxicity, inflammation, immunotoxicity, oxidative stress, antioxidant status, thyroid hormone and reproductive hormone dysregulations, gene expression analyses, metabolomics profiles and neurobehavioral testing for learning, memory and anxiety-like behavior. The average exposure concentration was 45.5 ± 5.9 micrograms/meter3. This produced an estimated body burden of 485 microgram/kilogram. Evaluation of neurobehavioral changes (using Morris Water Maze) in exposed and control animals was also compared to a positive control (exposure to 1-bromopropane, 1-BP).

This chronic SAM+ exposure study demonstrated impairment in spatial learning and memory, induction of anxiety-like behavior, disruption of cytokine and chemokine expression in liver and lung, reduction of white blood cells including neutrophils and lymphocytes, disruption of some metabolites especially amino acids, alteration of gene expression in brain tissue, and decreases in dopamine turnover in the striatum region.

In the last quarter of the current grant cycle, project researchers began a perinatal inhalation toxicology study of exposure to a PCB mixture more enriched in lower chlorinated congeners. This model includes nose-only exposure to female rats seven days prior to mating and then exposure continuing on gestational day eight until the pups are born. Dams and pups will continue to be exposed via whole-body inhalation until postnatal day 12.

Back
to Top