Urinary and breast milk biomarkers to assess exposure to naphthalene in pregnant women: an investigation of personal and indoor air sources

Abstract

BackgroundNaphthalene exposures for most non-occupationally exposed individuals occur primarily indoors at home. Residential indoor sources include pest control products (specifically moth balls), incomplete combustion such as cigarette smoke, woodstoves and cooking, some consumer and building products, and emissions from gasoline sources found in attached garages. The study aim was to assess naphthalene exposure in pregnant women from Canada, using air measurements and biomarkers of exposure.MethodsPregnant women residing in Ottawa, Ontario completed personal and indoor air sampling, and questionnaires. During pregnancy, pooled urine voids were collected over two 24-hour periods on a weekday and a weekend day. At 2–3 months post-birth, they provided a spot urine sample and a breast milk sample following the 24-hour air monitoring. Urines were analyzed for 1-naphthol and 2-naphthol and breast milk for naphthalene. Simple linear regression models examined associations between known naphthalene sources, air and biomarker samples.ResultsStudy recruitment rate was 11.2% resulting in 80 eligible women being included. Weekday and weekend samples were highly correlated for both personal (r = 0.83, p < 0.0001) and indoor air naphthalene (r = 0.91, p < 0.0001). Urine specific gravity (SG)-adjusted 2-naphthol concentrations collected on weekdays and weekends (r = 0.78, p < 0.001), and between pregnancy and postpartum samples (r = 0.54, p < 0.001) were correlated.Indoor and personal air naphthalene concentrations were significantly higher post-birth than during pregnancy (p < 0.0001 for signed rank tests); concurrent urine samples were not significantly different. Naphthalene in breast milk was associated with urinary 1-naphthol: a 10% increase in 1-naphthol was associated with a 1.6% increase in breast milk naphthalene (95% CI: 0.2%-3.1%). No significant associations were observed between naphthalene sources reported in self-administered questionnaires and the air or biomarker concentrations.ConclusionsMedian urinary concentrations of naphthalene metabolites tended to be similar to (1-naphthol) or lower (2-naphthol) than those reported in a Canadian survey of women of reproductive age. Only urinary 1-naphthol and naphthalene in breast milk were associated. Potential reasons for the lack of other associations include a lack of sources, varying biotransformation rates and behavioural differences over time.

Urinary biomarkers of polycyclic aromatic hydrocarbons in pre- and peri-pubertal girls in Northern California: Predictors of exposure and temporal variability

“…We identified 24.6% of participants with 1-naphthol/2-naphthol > 2 (suggestive of likely carbaryl exposure (Meeker et al, 2007). This is similar to the proportion reported in other U.S. study samples (Castorina et al, 2010; Li et al, 2012b, 2016) and higher than the proportion reported in other non-U.S. study samples (Wheeler et al, 2014); to our knowledge, this is the first study to document this finding in a sample of children. A higher proportion of girls with likely carbaryl exposure were white, higher SES as defined by parent education or household income, and lived in San Francisco.…”

The concentration of polycyclic aromatic hydrocarbons (PAHs) in mother milk: A global systematic review, meta-analysis and health risk assessment of infants

“…The main characteristic of collected studies is shown in Table 1 s. The studies were done all over the world. The following rank order was obtained for study zones, namely Europe including Italy, Japan, and Canada (5 studies, 39%)> ( Kishikawa et al 2003 ) ( Del Bubba et al, 2005 , Yu et al, 2011 , Wheeler et al, 2014 , Ilo et al, 2017 ), Asia including Turkey, China, and India (4 studies, 30.7%) >( Madhavan and Naidu, 1995 , Cok et al, 2012 , Wang et al, 2018 , Asamoah et al, 2019 ), America including Mexico, the USA, and Louisville, KY (3 studies, 20%) and Africa including ( Kim et al, 2008 , Hunter et al, 2010 , Acharya et al, 2019 ) Egypt, (1 study, 7.2 %) ( Hegazy et al 2020 ). All articels were published between 1991 and 2020.…”

“…Yu et al (2014) reported that the concentration of PAHs including anthracene, fluoranthene , pyrene, benz[a]anthracene , chrysene, benzo[b]fluoranthene , and benzo[k]fluoranthene was 14.4, 50.9, 36.5, 3.97, 7.42, 20.5, and 8.62 ng/g in various samples of mother milk, respectively ( Yu et al 2015 ). In another study conducted by Wheeler et al (2014) in Canada, the detected concentration of naphthalene in the mother milk was 7.75 ng/g ( Wheeler et al 2014 ). There are many differences between our results and other reports concerning the contamination of PAHs in breast milk samples, which can be related to critical factors such as physicochemical properties of individual PAHs, women-specific metabolic activity, age of mother, and type food consumed before milk collection ( Forehand et al, 2000 , Zanieri et al, 2007 ).…”

Characterization of a High PM2.5 Exposure Group in Seoul Using the Korea Simulation Exposure Model for PM2.5 (KoSEM-PM) Based on Time–Activity Patterns and Microenvironmental Measurements

“…Although such measurements can yield accurate data, there are time and resource limitations. Most personal exposure monitoring studies have focused on specific groups of subjects, such as medical patients [7,8], children [9,10,11,12], seniors [13,14], and workers [11,15,16]. Thus, these studies are not generalizable to the general population.…”