UCSF Studies of Second-Trimester Pregnant Women

Lab Collaboration

Analysis of flame retardants and other persistent chemicals in blood samples for studies of ethnically diverse, low-income pregnant women

Gloved hands in a laboratory, holding a test tube

The University of California San Francisco (UCSF) Studies of Second-Trimester Pregnant Women collected samples from 25 pregnant women seeking care at San Francisco General Hospital in 2008-09 and 36 pregnant women in 2011-12.  The study population consisted of ethnically diverse and predominantly low-income women in their second trimesters of pregnancy. These studies were a collaboration between Biomonitoring California laboratories and the UCSF Program on Reproductive Health and the Environment (PRHE).  The Program laboratories analyzed blood samples for persistent organic pollutants (polychlorinated biphenyls [PCBs], organochlorine pesticides, and polybrominated diphenyl ethers [PBDEs]), their metabolites (hydroxy-PCBs and hydroxy-PBDEs), and perfluorochemicals (PFCs). 

Study Findings

The first UCSF study of 25 women, sampled in 2008-09, found the highest PBDE levels ever reported among pregnant women world-wide.[1] The second UCSF study of 36 women, sampled three years later, showed a 39% decrease in PBDE levels, while the levels of hydroxy-metabolites of PBDEs decreased even more (by 86%).[2] [3]  In contrast, levels of legacy chemicals such as PCBs and hydroxy-metabolites of PCBs declined only slightly over the same time period.

Although PBDE levels appear to be dropping, Californians still have the highest measured levels in the world because of extensive past use of these flame retardant chemicals in consumer products.  California was the first state in the nation to legislate a ban on the commercial mixtures pentaBDE and octaBDE (AB 302 and later AB 2587; Health & Safety Code Section 108921 et seq.).  U.S. production of these two mixtures ended in 2006, and the last major PBDE mixture (decaBDE) was due to be phased out by the end of 2013.  Because of the PBDE bans and phase-outs, a further decline in PBDE levels is expected.  However, PBDEs are persistent in the environment and have entered the food supply, so some exposure will continue.



[1] Zota AR, Park J-S, Wang Y, Petreas M, Zoeller RT, Woodruff TJ. Polybrominated diphenyl ethers (PBDEs), hydroxylated PBDEs (OH-PBDEs), and measures of thyroid function in second trimester pregnant women in California. Environ Sci Technol 2011;45:7896-905. Free full text article

[2] Zota AR, Linderholm L, Park J-S, Petreas M, Guo T, Privalsky ML, Zoeller RT, Woodruff TJ. Temporal comparison of PBDEs, OH-PBDEs, PCBs, and OH-PCBs in the serum of second trimester pregnant women recruited from San Francisco General Hospital, California. Environ Sci Technol 2013. Free full text article

[3] Zota AR, Linderholm L, Park J-S, Petreas M, Guo T, Privalsky ML, Zoeller RT, Woodruff TJ. Correction to: A temporal comparison of PBDEs, OH-PBDEs, PCBs, and OH-PCBs in the serum of second trimester pregnant women recruited from San Francisco General Hospital, California. Environ. Sci. Technol. 2014; 48. 2512−2513.  Free full text article

 

Project Type: 

Laboratory collaboration

Project Status: 

Ongoing

Participants: 

25 pregnant women (2008-09) and 36 pregnant women (2011-12)

Sample Collection Date: 

2008 to 2012

Sample Collection Area: 

Northern California