Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Household chemicals may be linked to infertility

02.02.2009
Researchers at the UCLA School of Public Health have found the first evidence that perfluorinated chemicals, or PFCs — chemicals that are widely used in everyday items such as food packaging, pesticides, clothing, upholstery, carpets and personal care products — may be associated with infertility in women.

Published online in Human Reproduction, Europe's leading reproductive medicine journal, the study found that women who had higher levels of perfluorooctanoate (PFOA) and perfluorooctane sulfonate (PFOS) in their blood took longer to become pregnant than women with lower levels.

The UCLA researchers used data from the Danish National Birth Cohort to assess whether levels of PFOS and PFOA in pregnant women's plasma were associated with a longer time to pregnancy. A total of 1,240 women were included in their analyses.

Blood samples were first taken between 4 and 14 weeks into the pregnancy so that concentrations of PFOS and PFOA could be measured. The researchers also interviewed the women at around the 12th week of pregnancy to find out whether the pregnancy was planned or not and how long it took them to become pregnant. Infertility was defined as a time to pregnancy of longer than 12 months or a situation in which infertility treatments were used to establish the pregnancy, and the results were adjusted for potential confounding factors such as age, lifestyle and socioeconomic status.

The level of PFOS in the women's plasma ranged from 6.4 nanograms per milliliter (ng/ml) to 106.7 ng/ml, and from less than 1 ng/ml to 41.5 ng/ml for PFOA.

The researchers divided the women's levels of PFOS/PFOA into four quartiles and found that, compared with women with the lowest levels of exposure, the likelihood of infertility increased by 70 to 134 percent for women in the higher three quartiles of PFOS exposure and by 60 to 154 percent for women in the higher three quartiles of PFOA exposure.

"Perfluorooctanoate and perfluorooctane sulfonate were considered to be biologically inactive, but recently, animal studies have shown that these chemicals may have a variety of toxic effects on the liver, immune system and developmental and reproductive organs," said UCLA researcher Chunyuan Fei, the study's first author. "Very few human studies have been done, but one of our earlier studies showed that PFOA, although not PFOS, may impair the growth of babies in the womb, and another two epidemiological studies linked PFOA and PFOS to impaired fetal growth."

"As far as we know, this is the first study to assess the associations between PFOA and PFOS levels in plasma with time to pregnancy in humans," said principal investigator Jørn Olsen, chair of the department of epidemiology at the UCLA School of Public Health. "We are waiting for further studies to replicate our findings in order to discover whether the chemicals should be added to the list of risk factors for infertility."

In addition to being found in household goods, PFCs, the class of chemicals to which PFOS and PFOA belong, are used in manufacturing processes involving industrial surfactants and emulsifiers. They persist in the environment and in the body for decades.

The researchers believe that although they measured the PFOS/PFOA levels after pregnancy was established, these levels probably did not change significantly from the time before pregnancy. Men's sperm quality could also be affected by PFCs and might, therefore, contribute to the associations between PFC levels and time to pregnancy, since couples would tend to be sharing the same lifestyles and have similar exposures. However, the researchers did not have data on PFC levels in fathers.

"Studies on sperm quality and PFOA/PFOS are certainly warranted," Olsen said.

The researchers say the biological mechanisms by which exposure to PFOS and PFOA might reduce fertility are unknown, but PFCs may interfere with hormones that are involved in reproduction.

"Our data showed that higher proportions of women reported irregular menstrual periods in the upper three quartiles of PFOA and PFOS, compared with the lowest, and so this could indicate a possible pathway," Fei said.

Sarah Anderson | EurekAlert!
Further information:
http://www.ucla.edu
http://www.ph.ucla.edu

More articles from Health and Medicine:

nachricht Team discovers how bacteria exploit a chink in the body's armor
20.01.2017 | University of Illinois at Urbana-Champaign

nachricht Rabies viruses reveal wiring in transparent brains
19.01.2017 | Rheinische Friedrich-Wilhelms-Universität Bonn

All articles from Health and Medicine >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Traffic jam in empty space

New success for Konstanz physicists in studying the quantum vacuum

An important step towards a completely new experimental access to quantum physics has been made at University of Konstanz. The team of scientists headed by...

Im Focus: How gut bacteria can make us ill

HZI researchers decipher infection mechanisms of Yersinia and immune responses of the host

Yersiniae cause severe intestinal infections. Studies using Yersinia pseudotuberculosis as a model organism aim to elucidate the infection mechanisms of these...

Im Focus: Interfacial Superconductivity: Magnetic and superconducting order revealed simultaneously

Researchers from the University of Hamburg in Germany, in collaboration with colleagues from the University of Aarhus in Denmark, have synthesized a new superconducting material by growing a few layers of an antiferromagnetic transition-metal chalcogenide on a bismuth-based topological insulator, both being non-superconducting materials.

While superconductivity and magnetism are generally believed to be mutually exclusive, surprisingly, in this new material, superconducting correlations...

Im Focus: Studying fundamental particles in materials

Laser-driving of semimetals allows creating novel quasiparticle states within condensed matter systems and switching between different states on ultrafast time scales

Studying properties of fundamental particles in condensed matter systems is a promising approach to quantum field theory. Quasiparticles offer the opportunity...

Im Focus: Designing Architecture with Solar Building Envelopes

Among the general public, solar thermal energy is currently associated with dark blue, rectangular collectors on building roofs. Technologies are needed for aesthetically high quality architecture which offer the architect more room for manoeuvre when it comes to low- and plus-energy buildings. With the “ArKol” project, researchers at Fraunhofer ISE together with partners are currently developing two façade collectors for solar thermal energy generation, which permit a high degree of design flexibility: a strip collector for opaque façade sections and a solar thermal blind for transparent sections. The current state of the two developments will be presented at the BAU 2017 trade fair.

As part of the “ArKol – development of architecturally highly integrated façade collectors with heat pipes” project, Fraunhofer ISE together with its partners...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Sustainable Water use in Agriculture in Eastern Europe and Central Asia

19.01.2017 | Event News

12V, 48V, high-voltage – trends in E/E automotive architecture

10.01.2017 | Event News

2nd Conference on Non-Textual Information on 10 and 11 May 2017 in Hannover

09.01.2017 | Event News

 
Latest News

Helmholtz International Fellow Award for Sarah Amalia Teichmann

20.01.2017 | Awards Funding

An innovative high-performance material: biofibers made from green lacewing silk

20.01.2017 | Materials Sciences

Ion treatments for cardiac arrhythmia — Non-invasive alternative to catheter-based surgery

20.01.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>