Bisphenol A and phthalate metabolite urinary concentrations: Daily and across pregnancy variability.

Phthalates and bisphenol A (BPA) are high production volume and ubiquitous chemicals that are quickly metabolized in the body. Traditionally, studies have relied on single spot urine analyses to assess exposure; ignoring variability in concentrations throughout a day or over a longer period of time. We compared BPA and phthalate metabolite results from urine samples collected at five different time points. Participants (n=80) were asked to collect all voids in a 24 h period on a weekday and then again on a weekend before 20 weeks of pregnancy. During the second and third trimesters and in the postpartum period, single spot urines were collected. Variability over time in urinary concentrations was assessed using intraclass correlation coefficients (ICCs) and the sensitivity to correctly classify a single sample as high or low versus the geometric mean (GM) of all samples was calculated. We found low reproducibility and sensitivity of BPA and all phthalate metabolites throughout pregnancy and into the postpartum period but much higher reproducibility within a day. Time of day when the urine was collected was a significant predictor of specific gravity adjusted exposure levels. We concluded that, if the interest is in average exposures across pregnancy, maternal/fetal exposure estimation may be more accurate if multiple measurements, collected across the course of the entire pregnancy, rather than a single spot measure, are performed.

Maternal and infant exposure to environmental phenols as measured in multiple biological matrices.

BACKGROUND: Results of recent national surveys have shown the high prevalence of exposure to bisphenol A (BPA) and triclosan (TCS) among the general population; however biomonitoring data for pregnant women and infants are limited. METHODS: Women (n=80) were recruited from early prenatal clinics and asked to collect urine samples multiple times during pregnancy and once 2-3 months post-partum. Samples of infant urine and meconium as well as breast milk and infant formula were also collected. Biospecimens were analyzed by GC-MS/MS for BPA, TCS and triclocarban (TCC). RESULTS: Triclosan was detected in over 80% of the maternal urines (geometric mean (GM): 21.61 µg/L), 60% of the infant urines (GM: 2.8 µg/L), 46% of the breast milk and 80% of the meconium samples. Triclocarban was rarely detected in any of the biospecimens. Median total BPA concentrations were 1.21 and 0.24 µg/L in maternal and infant urines, respectively. Free BPA was detected in only 11% of infant urine samples. The meconium of female infants had significantly higher concentrations of total BPA and TCS than those of males, while no differences were observed in infant urine concentrations by sex. CONCLUSIONS: We found widespread exposure among pregnant women and infants to environmental phenols, with large inter-individual variability in exposure to triclosan. These data will contribute to the risk assessment of these chemicals, especially in susceptible sub-populations.

Phthalates in cosmetic and personal care products: concentrations and possible dermal exposure.

Phthalates are multifunctional chemicals that are used in a variety of consumer products including cosmetic and personal care products. This study aims at determining phthalate levels in cosmetic and personal care products obtained from the Canadian market. Overall 252 products including 98 baby care products were collected at retail stores in several provinces across Canada in year 2007. These products included fragrances, hair care products (hair sprays, mousses, and gels), deodorants (including antiperspirants), nail polishes, lotions (body lotions and body creams), skin cleansers, and baby products (oils, lotions, shampoos and diaper creams). Samples were extracted with different organic solvents, depending on the types of the products, followed by gas chromatography-mass spectrometry (GC-MS) analysis. Of the 18 investigated phthalates, diethyl phthalate (DEP), dimethyl phthalate (DMP), diisobutyl phthalate (DiBP), di-n-butyl phthalate (DnBP) and di(2-ethylhexyl) phthalate (DEHP) were detected. The detection frequencies were in the following order: DEP (103 out of 252 products)>DnBP (15/252)>DiBP (9/252)>DEHP (8/252)>DMP (1/252). DEP was detected in almost all types of surveyed products with the highest levels (25,542 µg/g, equal to 2.6%) found in fragrances. DnBP was largely present in nail polish products with the highest concentration of 24,304 µg/g (2.4%). DnBP was also found in other products such as hair sprays, hair mousses, skin cleansers and baby shampoos at much lower concentrations (36 µg/g and less). Levels of other detected phthalates were generally low in the products. Based on these values, daily dermal exposure dosage to five phthalates was estimated for three age groups, female adults (60 kg); toddlers (0.5-4 years) and infants (0-6 months), through the use of cosmetic and personal care products. The exposure estimation, however, was based on existing products use pattern data, instead of probabilistic model based population use distribution. For female adults, the maximal daily exposure of 78 µg/kg bw/d was determined for DEP. The maximal daily exposure was much lower for the other four phthalates (DEHP, 0.82 µg/kg bw/d; DnBP, 0.36 µg/kg bw/d; and DMP, 0.03 µg/kg bw/d). The exposure for DiBP was not calculated due to its very low levels (<10 µg/g) in products. Toddlers and infants in this case had a maximal daily exposure to DEP of 20 and 42 µg/kg bw/d, respectively.

Low molecular weight cyclic volatile methylsiloxanes in cosmetic products sold in Canada: implication for dermal exposure.

Low molecular weight cyclic volatile methylsiloxane (cVMS) compounds have been used in a variety of cosmetics and personal care products and many other consumer products. The study provides information on the levels of cVMSs in cosmetics and personal care products sold in Canada with an attempt to estimate the consumer dermal exposure to cVMSs from these products. The levels of four cVMS compounds, hexamethylcyclotrisiloxane (D3), octamethylcyclotetrasiloxane (D4), decamethylcyclopentasiloxane (D5), and dodecamethylcyclohexasiloxane (D6) were determined in 252 cosmetics and personal care products collected from retail stores in several provinces in Canada. These products included fragrances, hair care products, deodorants and antiperspirants, nail polishes, lotions, skin cleansers and a variety of baby products (baby oils, baby lotions, baby shampoos, and diaper creams). Samples were extracted with different organic solvents depending on the nature of the products followed by gas chromatograph-mass spectrometry (GC-MS) analysis. D3, D4, D5 and D6 were found in 0.8%, 4.8%, 14.3%, and 9.1% of the products, respectively. D5 was the most predominant cVMS with the highest concentration of 680 mg/g in an antiperspirant. D5 was also found to have the highest concentration in baby products (150 mg/g in a diaper cream). Several approaches were used to estimate consumer dermal exposure to cVMSs. A wide range of exposure estimates were derived as a result of the uncertainty in adsorption efficiency and penetration rates of cVMSs in human skin as well as in the degree of evaporative loss during products use.