foodconsumer.org: Reduced fertility linked to flame retardant exposure

Reduced fertility linked to flame retardant exposure
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admin on 01/29/2010 16:49:00
 
Women with high levels of flame retardants in their blood took longer to become
pregnant compared with those who had lower levels, a study by researchers at the
University of California Berkeley has found.
The study in the Jan 26, 2010 in the Journal Environmental Health Perspectives
showed each 10-fold increase in four types of polybrominated diphenyl ethers or
PBDEs was associated with a 30 percent decrease in the likelihood of becoming
pregnant each month.
Kim Harley, lead author of the study, said in a statement previous animal
studies have found exposure to PBDEs results in a wide spectrum of health
problems, but the current study is the first to find that these flame retardants
reduce fertility in child-bearing women.
PBDEs are a group of organobromine compounds that as flame retardants have found
all types of applications in household products including foam furniture,
electronics, fabrics, carpets ,plastics  and many others.
These flame retardants are successors to polychlorinated biphenyls or PCBs which
were banned in 1970 because of known toxicity.  Both types of flame retardants
are chemically similar in terms of their functions even though PBDEs are a
little less active than their counterparts.
PCBs were used as coolants and insulating fluids for transformers and
capacitors, pesticide extenders, cutting oils, flame retardants, hydraulic
fluids, sealants, adhesives, wood floor finishes, paints, de-dusting agents, and
in carbonless copy paper, according to wikipedia.
For the current study, the researchers measured PBDE levels in blood samples
collected from 223 Mexican women including those who were actively trying to
become pregnant.
Considered in the study were also menstrual cycles, frequency of intercourse,
pre-pregnancy body mass index, use of birth control pills in the year before
conception, smoking, and alcohol and caffeine consumption.
Women who had high levels of PBDEs were half as likely to conceive in any given
month as those who had low levels, the researchers found.
Fifteen percent of the women took longer than 12 months to become pregnant.
Two major flame retardants called Penta- and octaBD have been banned in some
states including California, but they are still found in products manufactured
before 2004.
It remains unknown exactly how these flame retardants affect the reproductive
system in females.  Animal studies showed that PBDEs can impair
neurodevelopment, reduce thyroid hormone, and change in levels of sex hormones.
By David Liu