Uterotrophic and Hershberger Assays for Endocrine Disruption Properties of Plastic Food Contact Materials Polypropylene (PP) and Polyethylene Terephthalate (PET)

Abstract

Plasticizers or plastic materials such as phthalates, bisphenol-A (BPA), and styrene are widely used in the plastic industry and are suspected endocrine-disrupting chemicals (EDC). Although plastic materials such as polypropylene (PP) and polyethylene terephthalate (PET) are not EDC and are considered to be safe, their potential properties as EDC have not been fully investigated. In this study, plastic samples eluted from plastic food containers (PP or PET) were investigated in Sprague-Dawley rats using Hershberger and uterotrophic assays. In the Hershberger assay, 6-wk-old castrated male rats were orally treated for 10 consecutive days with plastic effluent at 3 different doses (5 ml/kg) or vehicle control (corn oil, 1 ml/100 g) to determine the presence of both anti-androgenic and androgenic effects. Testosterone (0.4 mg/ml/kg) was subcutaneously administered for androgenic evaluation as a positive control, whereas testosterone (0.4 mg/ml/kg) and flutamide (3 mg/kg/day) were administered to a positive control group for anti-androgenic evaluation. The presence of any anti-androgenic or androgenic activities of plastic effluent was not detected. Sex accessory tissues such as ventral prostate or seminal vesicle showed no significant differences in weight between treated and control groups. For the uterotrophic assay, immature female rats were treated with plastic effluent at three different doses (5 ml/kg), with vehicle control (corn oil, 1 ml/100 g), or with ethinyl estradiol (3 μg/kg/d) for 3 d. There were no significant differences between test and control groups in vagina or uterine weight. Data suggest that effluents from plastic food containers do not appear to produce significant adverse effects according to Hershberger and uterotrophic assays.

The amount and detection method of styrene in foods: A systematic review and meta-analysis

“…The Table 1 shows extracted data from published paper. International agency for research on cancer grouped styrene to 2B as possible human carcinogen ( Chung et al, 2013 ). Therefore, it is necessary to regularly monitor this compound in food.…”

“…Polystyrene is one of the most commonly used compounds for packaging of food ( Brandsch and Schuster, 2020 , Cao et al, 2018 ). Styrene is used in polystyrene, polyamide, and acrylonitrile–butadiene–styrene ( Chung et al, 2013 , Marć et al, 2015 ). In humans, exposure with styrene occurs through food and respiration ( Tang, Hemm, & Eisenbrand, 2000 ).…”

Multigenerational exposure to dietary zearalenone (ZEA), an estrogenic mycotoxin, affects puberty and reproduction in female mice

“…All mice were housed in polypropylene cages with free access to a casein-based phytoestrogen-free AIN-93G diet (Bio-Serv, Frenchtown, NJ) or a ZEA in AIN-93G diet and to water in polypropylene water bottles. Polypropylene containers were not significant sources for endocrine disruption [12]. Generally, ZEA levels in rodent diets were undetectable or very low (<30 ppb) [13, 14].…”

Comparative Cytotoxicity and Sperm Motility Using a Computer-Aided Sperm Analysis System (CASA) for Isomers of Phthalic Acid, a Common Final Metabolite of Phthalates

“…PAE produce reproductive and developmental toxicities, among other adverse health effects (Autian, 1973;Hill et al, 2003;Koo and Lee, 2005;Chung et al, 2013;Bhat et al, 2014;Guerra et al, 2014). Several in vitro and in vivo toxicological studies demonstrated a wide range of systemic and target organ toxicities (Filho Ido et al, 2013;Yoon et al, 2014).…”