Butylparaben multigenerational reproductive assessment by continuous breeding in Hsd:Sprague Dawley SD rats following dietary exposure

Abstract

Butylparaben (BP) is an antimicrobial agent utilized for decades as a preservative in numerous consumer products. The safety of parabens has recently come under scrutiny based on reports of estrogenic activity and suggested adverse effects upon the reproductive system. Due to the limited availability of studies that address the potential for BP exposure to induce reproductive toxicity, and clear evidence of human exposure, the National Toxicology Program conducted a multigenerational continuous breeding study to evaluate the impact of dietary BP-exposure at 0, 5000, 15,000, or 40,000 ppm on reproductive and developmental parameters in Hsd:Sprague Dawley SD rats. BP-exposure was not associated with adverse alterations of fertility, fecundity, pubertal attainment, or reproductive parameters in F0, F1, or F2 generations. Exposure-dependent increases in liver weights, and incidences of non-neoplastic liver lesions suggest the liver is a target organ of BP toxicity. No findings were observed that would support the purported mechanism of BP-induced endocrine disruption in perinatally-exposed rodents.

Keywords: Butylparaben; Development; Reproduction; Toxicity.

Fig. 1.

Representative diagram depicting overall RACB study design.

Fig. 2.

Summary of relative body weights (% control) of study animals measured across multiple generations/reproductive intervals, (A) F0 male/female, (B) F0 females during gestation intervals A, B, and C, (C) F0 females during lactation interval (litter C), and (D) F1c male/female pups prior to weaning.

Fig. 3.

Summary of relative body weights (% control) of study animals measured across multiple generations/reproductive intervals, (A) F1c male/female (post-weaning), (B) F1c females during gestation intervals A, B, and C, (C) F1c females during lactation interval (litter C), and (D) F2c male/female pups prior to weaning.