Science Inventory

Chronic exposure to low levels of dibromoacetic acid, a water disinfection by-product, adversely affects reproductive function in male rabbits

Citation:

RAO VEERAMACHANENI, D. N., J. S. PALMER, AND G. R. KLINEFELTER. Chronic exposure to low levels of dibromoacetic acid, a water disinfection by-product, adversely affects reproductive function in male rabbits. JOURNAL OF ANDROLOGY. American Society of Andrology, Schaumburg, IL, 28(4):565-577, (2007).

Impact/Purpose:

To determine the extent to which chronic exposure to DBA affects reproductive function

Description:

Four groups (minimum of 10/dose group) of male Dutch-Belted rabbits were treated daily to dibromoacetic acid (DBA) via drinking water beginning in utero from gestation day 15 throughout life; target dosages were 1, 5, and 50 mg DBA /kg body weight. Developmental, prepubertal as well as postpubertal reproductive sequelae were evaluated. One (out of 22), 2 (out of 32), and 1 (out of 21) in 1, 5, and 50 mg DBA/kg groups were unilaterally cryptorchid. There were no significant differences in serum FSH, LH and testosterone (basal concentrations or in response to exogenous GnRH) in both prepubertal and adult rabbits. Chronic exposure to DBA adversely affected mating ability of some rabbits. Number of sperm produced was not affected but spermiogenesis was disrupted resulting in unique sperm acrosomal-nuclear malformations even at 1 mg dose level. Concentrations of SP22, a specific sperm membrane fertility protein, in detergent extracts of ejaculated sperm were significantly lower (p < 0.05) in all DBA-treated groups compared to controls. The conception rates following artificial insemination of a constant number of sperm for 1, 5, and 50 mg DBA/kg groups were, 55 (10/18), 65 (13/20), and 55% (9/16), respectively, vs. 85% (17/20) for control group. Histological lesions in testes characterized by spermatogenic arrest predominantly at round spermatid stage, pyknosis of differentiating germ cells, and ultimate degeneration and desquamation leaving focal vacuolation in seminiferous epithelium were evident in DBA-treated groups. Thus, a new low-effect-level of 1 mg DBA/kg was established on effects observed in multiple male reproductive parameters.

Record Details:

Record Type:DOCUMENT( JOURNAL/ PEER REVIEWED JOURNAL)
Product Published Date:07/01/2007
Record Last Revised:01/07/2008
OMB Category:Other
Record ID: 164586