HEALTH NEWS

Study Title:

Prenatal Pesiticide Exposure and Obesity

Study Abstract

Objectives: To investigate the effect of prenatal exposure to polychlorinated biphenyls (PCBs) and dichlorodiphenyl-dichloroethylene (DDE) on weight, height and body mass index (BMI) in adult female offspring of the Michigan fisheater cohort examined between 1973 and 1991.

Methods: 259 mothers from the Michigan fisheater cohort were studied. Prenatal exposure to PCBs and DDE was estimated by extrapolating maternal measurements to the time that the women gave birth. 213 daughters aged 20–50 years in 2000 were identified and 83% of them participated in at least one of two repeated investigations in 2001/02 (n = 151) and 2006/07 (n = 129). To assess the effect of prenatal PCB and DDE exposure on anthropometric measurements, generalised estimating equations nested for repeated measurements (2001/02 and 2006/07) and for sharing the same mother were used. We controlled for maternal height and BMI and for daughters’ age, birth weight, having been breastfed and number of pregnancies.

Results: Maternal height and BMI were significant predictors of the daughters’ height, weight and BMI. Low birth weight (<2500 g) was significantly associated with reduced adult offspring weight and BMI. The weight and BMI of adult offspring were statistically significantly associated with the extrapolated prenatal DDE levels of their mothers. Controlling for confounders and compared to maternal DDE levels of <1.503 µg/l, offspring BMI was increased by 1.65 when prenatal DDE levels were 1.503–2.9 µg/l and by 2.88 if levels were >2.9 µg/l. Prenatal PCB levels showed no effect.

Conclusion: Prenatal exposure to the oestrogenic endocrine-disrupting chemical DDE may contribute to the obesity epidemic in women.

From press release:

Prenatal exposure to an insecticide commonly used up until the 1970s may play a role in the obesity epidemic in women, according to a new study involving several Michigan State University researchers.


More than 250 mothers who live along and eat fish from Lake Michigan were studied for their exposure to DDE – a breakdown of DDT. The study, published as an editor’s choice in this month’s edition of Occupational and Environmental Medicine, analyzed DDE levels of the women’s offspring.

Compared to the group with the lowest levels, those with intermediate levels gained an average of 13 pounds excess weight, and those with higher levels gained more than 20 pounds of excess weight.

“Prenatal exposure to toxins is increasingly being looked at as a potential cause for the rise in obesity seen worldwide,” said Janet Osuch, a professor of surgery and epidemiology at MSU’s College of Human Medicine, who was one of the lead authors of the study. “What we have found for the first time is exposure to certain toxins by eating fish from polluted waters may contribute to the obesity epidemic in women.”

Though DDT was banned in 1973 after three decades of widespread use, the chemical and its byproducts remain toxic in marine life and fatty fish. The study was funded by a $300,000 grant from the federal Agency for Toxic Substances and Disease Registry.

Osuch said the study’s findings can have a huge impact on how researchers treat – and seek to prevent – obesity. The research team has been awarded a $1 million grant from the same federal agency, the ATSDR, to assess the impact of pollutants and toxins on a wide variety of disorders by determining the importance of second- and third-generation health effects.

“This line of research can transform how we think about the causes of obesity and potentially help us create prenatal tests to show which offspring are at higher risks,” she said.

The mothers who were studied are part of a larger cohort of Michigan fish eaters along Lake Michigan who were recruited in the early 1970s. In 2000, Osuch and research partners approached the cohort and began to identify daughters aged 20 to 50 years old.

“These findings not only apply to the offspring of women in our cohort but to any woman who has been exposed to high levels of DDE when she was growing in her mother’s womb,” Osuch said. “Mothers with the highest DDE levels are women who have consumed a lot of fish or high-fat meats.”

Current recommendations for eating fish call for limiting it to two meals per week; including tuna fish sandwiches. The study also looked at the effects of a second pollutant, PCBs, but found no correlation with weight and body mass index.

Study Information

W Karmaus, J R Osuch, I Eneli, L M Mudd, J Zhang, D Mikucki, P Haan, S Davis.
Maternal levels of dichlorodiphenyl-dichloroethylene (DDE) may increase weight and body mass index in adult female offspring.
Occupational and Environmental Medicine.
2009 March
Departments of Surgery and Epidemiology, College of Human Medicine, Michigan State University, East Lansing, Michigan, USA.

Full Study

http://oem.bmj.com/cgi/reprint/66/3/143