Human urinary excretion of non-persistent environmental chemicals: an overview of Danish data collected between 2006 and 2012

Abstract

Several non-persistent industrial chemicals have shown endocrine disrupting effects in animal studies and are suspected to be involved in human reproductive disorders. Among the non-persistent chemicals that have been discussed intensively during the past years are phthalates, bisphenol A (BPA), triclosan (TCS), and parabens because of their anti-androgenic and/or estrogenic effects. Phthalates are plasticizers used in numerous industrial products. Bisphenol A is the main component of polycarbonate plastics and epoxy resins. Parabens and TCS are antimicrobial preservatives and other phenols such as benzophenone-3 (BP-3) act as a UV-screener, while chlorophenols and phenyl phenols are used as pesticides and fungicides in agriculture. In spite of the widespread use of industrial chemicals, knowledge of exposure sources and human biomonitoring studies among different segments of the population is very limited. In Denmark, we have no survey programs for non-persistent environmental chemicals, unlike some countries such as the USA (NHANES) and Germany (GerES). However, we have analyzed the excretion of seven parabens, nine phenols, and the metabolites of eight different phthalates in urine samples collected over the past 6 years from four Danish cohorts. Here, we present biomonitoring data on more than 3600 Danish children, adolescents, young men, and pregnant women from the general population. Our study shows that nearly all Danes were exposed to the six most common phthalates, to BPA, TCS, and BP-3, and to at least two of the parabens. The exposure to other non-persistent chemicals was also widespread. Our data indicate decreasing excretion of two common phthalates (di-n-butyl phthalate and di-(2-ethylhexyl) phthalate) over time.

Effect of environmental phthalate exposure on pregnancy duration and birth outcomes

“…In addition, high-MWP (as the sum of molar concentrations of MEHP, MEHHP, MEOHP, MHiNP, MOiNP and MOP) and low-MWP (as the sum of molar concentrations of MEP, MiBP, MnBP, OH-MnBP and MBzP) were calculated. The selected phthalate metabolites were similar as in other studies and indicated the proxy of exposure to different types of products [1,12,[19][20][21][22].…”

“…Levels of most of the phthalate metabolites detected in the urine of pregnant women in Poland were in an order of magnitude similar to that observed among pregnant women in Denmark [27]. It is important to note that MEP levels were much lower in Poland (as well as in Denmark and Japan) compared to those observed in Spain, France, the Netherlands and US [10][11][12][27][28][29]. In addition, MBzP was detected only in 49% of Polish samples, which is similar to the results observed in Denmark (MBzP > LOD in 69% of the samples) but lower metabolites.…”

“…In the case of MBzP and MOiNP, in our study such values were lower and in the case of MHiNP they were on the same level. Levels of most of the phthalate metabolites detected in the urine of pregnant women in Poland were in an order of magnitude similar to that observed among pregnant women in Denmark [27]. It is important to note that MEP levels were much lower in Poland (as well as in Denmark and Japan) compared to those observed in Spain, France, the Netherlands and US [10][11][12][27][28][29].…”

“…While the majority of animal studies on DEP do not show reproductive and developmental toxicity [34,35], some of the human studies have found significant adverse associations [6]. than in the other mentioned studies (where MBzP was detected in 100% of the samples) [10][11][12][27][28][29].…”

“…In animal studies, phthalates induced a variety of adverse effects, among which most were related to reproductive and developmental outcomes. Phthalates are considered to be endocrine disrupting chemicals in many aspects, including estrogenic, anti-androgenic and anti-thyroid activities [19,33,34]. Pregnant rats exposed to phthalates had reductions in ovarian and uterine weight, progesterone levels and ovulatory follicles.…”