Transplacental passage of antimicrobial paraben preservatives.

Parabens are widely used preservatives suspected of being endocrine disruptors, with implications for human growth and development. The most common paraben found in consumer products is methylparaben. To date, no study has examined whether these substances cross the human placenta. A total of 100 study subjects (50 mother-child pairs) were enrolled at two medical institutions, serving primarily African-American and Caucasian women, respectively. A maternal blood sample was drawn on admission and a paired cord blood sample was obtained at delivery. Of the 50 mothers, 47 (94%) showed methylparaben in their blood (mean level 20.41 ng/l), and 47 in cords bloods (mean level 36.54 ng/l). There were 45 mother-child pairs where methylparaben was found in both samples. Of these, the fetal level was higher than the maternal level in 23 (51%). For butylparaben, only 4 mothers (8%) showed detectable levels (mean 40.54 ng/l), whereas 8 cord blood samples (16%) were positive (mean 32.5 ng/l). African-American mothers and infants showed higher prevalence of detectable levels (P=0.017). Methylparaben and butylparaben demonstrate transplacental passage. Additional studies are needed to examine potential differences in exposure by geography and demographics, what products are used by pregnant women that contain these preservatives, as well as any potential long-term effects in the growth and development of exposed children.

Early life triclocarban exposure during lactation affects neonate rat survival.

Triclocarban (3,4,4'-trichlorocarbanilide; TCC), an antimicrobial used in bar soaps, affects endocrine function in vitro and in vivo. This study investigates whether TCC exposure during early life affects the trajectory of fetal and/or neonatal development. Sprague Dawley rats were provided control, 0.2% weight/weight (w/w), or 0.5% w/w TCC-supplemented chow through a series of 3 experiments that limited exposure to critical growth periods: gestation, gestation and lactation, or lactation only (cross-fostering) to determine the susceptible windows of exposure for developmental consequences. Reduced offspring survival occurred when offspring were exposed to TCC at concentrations of 0.2% w/w and 0.5% w/w during lactation, in which only 13% of offspring raised by 0.2% w/w TCC dams survived beyond weaning and no offspring raised by 0.5% w/w TCC dams survived to this period. In utero exposure status had no effect on survival, as all pups nursed by control dams survived regardless of their in utero exposure status. Microscopic evaluation of dam mammary tissue revealed involution to be a secondary outcome of TCC exposure rather than a primary effect of compound administration. The average concentration of TCC in the milk was almost 4 times that of the corresponding maternal serum levels. The results demonstrate that gestational TCC exposure does not affect the ability of dams to carry offspring to term but TCC exposure during lactation has adverse consequences on the survival of offspring although the mechanism of reduced survival is currently unknown. This information highlights the importance of evaluating the safety of TCC application in personal care products and the impacts during early life exposure.

Hydraulic fracturing: paving the way for a sustainable future?

With the introduction of hydraulic fracturing technology, the United States has become the largest natural gas producer in the world with a substantial portion of the production coming from shale plays. In this review, we examined current hydraulic fracturing literature including associated wastewater management on quantity and quality of groundwater. We conclude that proper documentation/reporting systems for wastewater discharge and spills need to be enforced at the federal, state, and industrial level. Furthermore, Underground Injection Control (UIC) requirements under SDWA should be extended to hydraulic fracturing operations regardless if diesel fuel is used as a fracturing fluid or not. One of the biggest barriers that hinder the advancement of our knowledge on the hydraulic fracturing process is the lack of transparency of chemicals used in the practice. Federal laws mandating hydraulic companies to disclose fracturing fluid composition and concentration not only to federal and state regulatory agencies but also to health care professionals would encourage this practice. The full disclosure of fracturing chemicals will allow future research to fill knowledge gaps for a better understanding of the impacts of hydraulic fracturing on human health and the environment.