Submitted November 23, 2004
Returned for revision January 14, 2005
Accepted April 27, 2005
Toxicology
In Utero and Lactational Exposure to an Environmentally
Relevant Organochlorine Mixture Disrupts Reproductive
Development and Function in Male Rats
Mohamed-Kheir Idris Anas ,
Christine Guillemette ,
Pierre Ayotte ,
Daria Pereg ,
Francine Giguère ,
and
Janice L. Bailey *
* To whom correspondence should be addressed. E-mail: janice.bailey{at}crbr.ulaval.ca.
Abstract
We hypothesized that in utero and lactational exposure of
male rats to a mixture of >15 organochlorines, resembling
that found in blubber from Northern Quebec seals, alters
reproductive development and function. Female rats were
gavaged with either corn oil (controls) or the
organochlorine mixture in increasing doses (low, medium,
high) for 5 weeks before mating and through gestation.
Developmental effects were monitored in the male offspring
from postnatal day (PND) 2 until PND90. The high dose
mixture reduced the number of pups per litter, percentage
of live offspring and pup weights (P<0.05). Because only
3 rats from the high dose treatment survived, data from
this group beyond PND2 were not included in the
statistical analyses. As assessed by the time of
preputial separation, puberty was delayed in the pups from
treated dams (P<0.05). Testes weights in the medium dose
group were greater than in controls on PND21 (P<0.05).
Ventral prostate weights were lower for the medium dose on
PND60 (P<0.05). On PND90, weights of the epididymis,
ventral prostate and seminal vesicle of the medium dose
rats were reduced compared to controls (P<0.05). PND90
sperm motility parameters assessed by computer-assisted
sperm analysis were altered in the low and medium dose
groups (P<0.05). Testis and epididymis morphology was
severely affected in rats exposed to the high dose of the
mixture. Serum testosterone, LH, FSH, prolactin and total
thyroxin levels did not differ due to organochlorine
treatment. Therefore, in utero and lactational exposure
to an environmentally relevant organochlorine mixture
adversely affects the reproductive system of male rats,
perhaps via antiandrogenic effects during testis
development, suggesting a possible reproductive health
hazard for humans and other species.
Key words:
Environment •
Male Reproductive Tract •
Toxicology •
Puberty •
Sperm
