Urinary concentrations of parabens and reproductive parameters in young men.

Parabens are a group of alkyl esters of p-hydroxybenzoic acid that are commonly added to personal care products, cosmetics, pharmaceuticals and beverage and food processing as antimicrobial preservatives. Parabens have been reported to show estrogenic effects and affect male reproduction function in animal models, but human epidemiologic studies are still scarce. The objective of this study was to examine associations between urinary concentrations of parabens and semen quality and reproductive hormone levels. This was a cross-sectional study with 215 young university students (18-23years old) recruited between 2010 and 2011 in Southern Spain (Murcia Region). All men provided a urine, blood and semen sample on a single day. Urinary paraben concentrations (methylparaben, ethylparaben, propylparaben and butylparaben) were measured by dispersive liquid-liquid microextraction and ultra-high performance liquid chromatography with tandem mass spectrometry detection. Semen quality was evaluated by measuring volume, sperm concentration, total sperm count (TSC), motility and morphology following WHO guidelines. Serum samples were analyzed for reproductive hormones, including follicle-stimulating hormone, luteinizing hormone, testosterone, inhibin B and estradiol using immunoassays. Associations between urinary concentrations of parabens and semen quality parameters and reproductive hormone levels were examined using linear regression, adjusting for potential covariates. Ninety-four percent of the men had detectable urinary concentrations of parabens. After taking into account important covariates, urinary concentrations of parabens or their molar sum were not significantly associated with any semen parameters or any of the reproductive hormone levels. Relative to men in the lowest quartile of sum of urinary paraben concentrations, the adjusted difference (95% CI) of TSC (millions) for men in the 2nd, 3rd, and 4th quartiles were 4.1% (-37.1;45.3), -1.6% (-41.9;38.8), and -9.8% (-52.5;32.8), respectively (P-trend=0.55). Our results suggest that, in young men, urinary parabens may not adversely impact reproductive function, but further research is warranted to confirm these findings in other male populations.

Adoamnei E ，Mendiola J ，Moñino-García M ，Vela-Soria F ，Iribarne-Durán LM ，Fernández MF ，Olea N ，Jørgensen N ，Swan SH ，Torres-Cantero AM ... -  《-》

Urinary concentrations of benzophenone-type ultra violet light filters and reproductive parameters in young men.

Benzophenone (BP)-type ultraviolet (UV) light filters are chemicals frequently added to personal care products, insect repellents, sunscreens, and beverage and food packaging to diminish the harmful effects of UV sunlight on human skin or foodstuffs. BP-type UV filters have shown negative effects on male reproduction function in in vitro and animal models, but human epidemiologic studies are limited. The goal of this study was to examine associations between urinary concentrations of BP-type UV filters and semen quality and reproductive hormone levels. This is a cross-sectional study with 215 young university students (18-23 years old) recruited between 2010 and 2011 in Southern Spain (Murcia Region). All men provided a urine, blood and semen sample on a single day. Urinary concentrations of 2,4-dihydroxybenzophenone (BP-1); 2,2',4,4'-tetrahydroxybenzophenone (BP-2); 2-hydroxy-4-methoxybenzophenone (BP-3); 2,2'-dihydroxy-4-methoxybenzophenone (BP-8) and 4-hydroxybenzophenone (4OH-BP) were measured by dispersive liquid-liquid microextraction and ultra-high performance liquid chromatography with tandem mass spectrometry detection. Semen quality was evaluated by measuring volume, sperm counts, motility and morphology. Serum samples were analyzed for reproductive hormones, including follicle-stimulating hormone (FSH), luteinizing hormone (LH), testosterone (T), inhibin B and estradiol (E2). Associations between urinary concentrations of BP-type UV filters and semen quality parameters and reproductive hormone levels were examined using linear regression, adjusting for potential confounders. Ninety-seven percent of the men had detectable urinary concentrations of at least one of the five BP-type UV filters quantified. After adjustment for important covariates (body mass index, smoking status and time of blood sample collection), there was a significant positive association between urinary BP-1 and BP-3 concentrations and serum FSH levels (β = 0.08, 95%CI: 0.009; 0.15 and β = 0.04, 95%CI: 0.0002; 0.08, respectively). Urinary BP-1 concentration was also significantly positively associated with T/E2 (β = 0.04, 95%CI: 0.002; 0.07) and negatively with inhibin b/FSH (β = -0.11, 95%CI: -0.21; -0.006) ratio. No significant associations were found between other urinary BP-type UV filters and other reproductive hormone levels or between any semen parameters and any of the urinary BP-type UV filters quantified. Our results suggest that, in young men, urinary BP-type UV filters may be associated with a modest alteration of some reproductive hormones, but the effects we report on reproductive function are likely to be small, and of unclear clinical significance. Further research is needed to replicate these findings in other male populations.

Adoamnei E ，Mendiola J ，Moñino-García M ，Vela-Soria F ，Iribarne-Durán LM ，Fernández MF ，Olea N ，Jørgensen N ，Swan SH ，Torres-Cantero AM ... -  《-》

Urinary bisphenol A concentrations are associated with reproductive parameters in young men.

Bisphenol A (BPA) is a pervasive environmental toxicant with known reproductive effects on sperm parameters and hormone levels. Several observational studies have investigated the associations between BPA exposure and male reproductive function, but findings are inconsistent. The objective of this study was to assess the associations between urinary BPA concentrations and semen quality and reproductive hormone levels in a cross-sectional study with 215 healthy young university students (18-23 years old), investigated between 2010 and 2011 in Southern Spain (Murcia Region). All subjects provided urine, blood serum and semen samples on a single day. Urinary BPA concentrations were measured by dispersive liquid-liquid microextraction and ultra-high performance liquid chromatography with tandem mass spectrometry detection. Semen quality was evaluated by measuring volume, concentration, motility, morphology and total sperm count (TSC). Serum samples were analyzed for reproductive hormones, including follicle-stimulating hormone (FSH), luteinizing hormone (LH), testosterone, inhibin B and estradiol. Relationships between urinary BPA concentrations and semen quality parameters and reproductive hormone levels were examined using linear regression, adjusting for potential confounders and covariates. Ninety-five percent of the men had detectable urinary BPA concentrations with unadjusted median (5th-95th) of 2.8 (0.16-11.5) ng/mL. After adjustment for important covariates, there was a significant positive association between urinary BPA concentrations and serum LH levels (β = 0.07, 95%CI: 0.02;0.12, p-value < 0.01). Urinary BPA concentration was also significantly and inversely associated with sperm concentration (β = - 0.04, 95%CI: - 0.07;- 0.02, p-value < 0.01) and TSC (β = - 0.05, 95%CI: - 0.08;- 0.02, p-value < 0.01). No significant associations were found between BPA and other semen parameters or reproductive hormone levels. Our results support the hypothesis that BPA exposure may be associated with a reduction in Leydig cell capacity (increased LH levels) and decreased sperm counts in young men.

Adoamnei E ，Mendiola J ，Vela-Soria F ，Fernández MF ，Olea N ，Jørgensen N ，Swan SH ，Torres-Cantero AM ... -  《-》

Final amended report on the safety assessment of Methylparaben, Ethylparaben, Propylparaben, Isopropylparaben, Butylparaben, Isobutylparaben, and Benzylparaben as used in cosmetic products.

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Urinary excretion of phenols, parabens and benzophenones in young men: Associations to reproductive hormones and semen quality are modified by mutations in the Filaggrin gene.

The filaggrin gene (FLG) encodes an epidermal protein, filaggrin, which is important for normal skin barrier functions. We previously showed that FLG loss-of-function mutation carriers have a higher internal exposure to some non-persistent chemicals such as certain phthalates and parabens, suggesting increased trans-epidermal penetration. Several groups of non-persistent chemicals are suspected endocrine disrupters with potential to affect testicular function. To investigate associations between exposure to non-persistent chemicals and testicular function in young Danish men with and without FLG mutations. We measured urinary concentrations of bisphenol A (BPA) and other simple phenols, parabens, and UV filters including benzophenones (BP-1, BP-3 and 4-HBP) in men genotyped for FLG R501X, 2282del4, and R2447X loss-of-function mutations; in total 65 mutation carriers and 130 non-carriers (controls) were included. Outcomes were markers of testicular function, assessed by serum reproductive hormones and semen quality. We found that associations between urinary chemical concentrations and outcomes were different in cases and controls. Within the group of FLG mutation carriers, higher urinary concentrations of BPA, BP-1 and BP-3 were associated with higher testosterone and estradiol serum levels and lower FSH. Similar trends in hormone levels were observed for FLG mutation carriers with measurable levels of 4-HBP compared to those who had no detectable levels of urinary 4-HBP. Furthermore, those in the highest urinary BPA quartile had lower sperm motility than those in the lower quartiles. None of these associations were evident in the control group. In the control group, however, lower sperm motility and sperm concentration were observed in the men with detectable urinary 4-HBP compared to the men non-detectable urinary 4-HBP. We found no association between any parabens and outcomes, nor for the other measured phenols or UV filters. Associations between male reproductive health parameters and urinary levels of BPA and benzophenones such as BP-3, BP-1 and 4-HBP were observed in FLG mutation carriers but not in controls from the same study population. This difference between FLG mutation carriers and non-carriers is not explained solely by differences in exposure levels of the examined compounds as e.g. BPA and 4-HBP urinary levels did not differ between the two groups. We hypothesise that effects of exposure to these compounds may be modulated in FLG mutation carriers by either different levels of co-exposures or by route of uptake, with a higher fraction of the uptake by dermal uptake.

Joensen UN ，Jørgensen N ，Thyssen JP ，Szecsi PB ，Stender S ，Petersen JH ，Andersson AM ，Frederiksen H ... -  《-》