Study: Grandmaternal Perinatal Serum PCBs and Prevalence of Obesity in Adult Daughters and Granddaughters

A first-of-its-kind study from PHI’s Child Health and Development Studies that shows that a grandmother’s exposure to PCBs can result in a higher obesity risk for her daughter/s and granddaughter/s. 

The research, published in the journal Obesity and co-authored by PHI’s Dr. Barbara Cohn, examines the relationship of grandmothers’ perinatal serum polychlorinated biphenyl (PCB)—persistent pollutants stored in the fat of animals and humans—and obesity at reproductive age in a three-generation human cohort.

Polychlorinated biphenyls (PCBs) are synthetic organic chemicals that were once widely used in manufacturing for their non-flammability and electrical insulating properties, particularly in transformers, capacitors, and coolants. However, due to their environmental persistence and toxic effects, PCBs were banned in many countries starting in the late 1970s. Exposure to PCBs, whether through inhalation, ingestion, or skin contact, has been linked to a range of health problems, including cancer, immune system suppression, reproductive disorders, and developmental issues in children. Despite the ban, PCB contamination remains a concern in older equipment and manufacturing sites, posing ongoing risks to human health and the environment.

While earlier studies in the field have shown that environmental pollutants contribute to the rise of obesity, there is a lack of multigenerational human studies that begin in utero. From a human development perspective, this is an especially critical window for understanding exposures and susceptibility. This study looks at in utero exposures by using unique data from PHI’s Child Health and Development Studies cohort, which spans 60+ years of data from over 15,000 families—across 3 and sometimes 4 generations.

Researchers found that maternal pregnancy blood levels of three PCBs—already discovered to perturb fat composition in animals—were associated risk of living with obesity in daughters and granddaughters of reproductive age. Additionally, having obesity during pregnancy also contributed to having daughters with obesity so that the initial chemical exposure could have lasting effects for additional future generations. Findings include:

• Relative amounts of PCB 138, PCB 153, and PCB 180 in grandmaternal perinatal serum associated prospectively and independently with obesity in daughters and granddaughters of reproductive age.
• Grandmaternal and maternal obesity also independently associated with obesity in daughters and granddaughters of reproductive age.
• Susceptibility of the developing fetus to environmental obesogens and a cycle of subsequent maternal obesity could explain and perpetuate increasing prevalence of obesity.

These findings could help explain the current obesity epidemic and can enhance discovery of new prevention opportunities. Authors suggest that finding ways to interrupt this obesity cycle is a critical research and public health priority.

Originally published by Obesity Research Journal