July 13, 2005

Male fertility not harmed by phthalates-study

By Will Boggs, MD

NEW YORK (Reuters Health) - Contrary to earlier reports,
everyday exposure to phthalates -- chemical plasticizers used
extensively in household products and in certain medical
products -- may not have harmful effects on fertility in young
men, a new study shows.

Previous studies suggested that low levels of phthalate
exposure could adversely affect human semen, the authors
explain in a report in Epidemiology, a medical journal, but
high doses of phthalates are required to provoke male
reproductive toxicity in rats.

For their study, Dr. Bosse A.G. Jonsson from Lund
University Hospital, Sweden, and colleagues looked for
associations between phthalate metabolite levels in urine and
semen quality and reproductive hormone parameters in 234 young
Swedish men entering the military.

There was "no clear pattern of associations" between any of
the phthalate metabolites and any of the biomarkers of
reproductive function measured.

In fact, exposure to phthalic acid seemed to be associated
with improved reproductive function, as measured by several

"I do not think it is clear whether phthalate constitutes a
risk for the male fertility," Jonsson told Reuters Health.
"More studies must be performed."

"We plan to study biological samples stored in biobanks
from pregnant mothers and study the fertility in their grown-up
male children," Jonsson added.

SOURCE: Epidemiology, July 2005.