OBJECTIVE: We investigated associations between OPE exposures as measured in house dust and emotional and behavioral problems in young children.
METHODS: We used data from the CHILD Cohort Study (n = 601), a prospective birth cohort recruited in 5 cities across Canada (2008-2012). OPEs were measured in house dust at 3-4 months postpartum, and parents completed the Child Behavior Checklist (CBCL), which measures emotional and behavioral problems when their child was 5 years. We used logistic regression to examine associations between OPE Z-scores (individual and summed chlorinated [ΣOPECl] and non-chlorinated [ΣOPENCl]) and CBCL problem scale scores (borderline and clinical T-scores ≥60 and normal <60).
RESULTS: Tris(2-chloroethyl) phosphate (TCEP) showed strong, positive associations with CBCL Total and Externalizing scores at or above the clinical cutoff, meaning children with higher levels of TCEP in house dust postpartum had higher odds of developing clinically relevant behavioral problems in early childhood compared to children with lower levels (Total ORadj: 1.37, 95% CI: 1.01, 1.87; Externalizing ORadj: 1.36, 95% CI: 1.00, 1.85). Similarly, 4-isopropylphenyl diphenyl phosphate, a Firemaster 550 component, had a strong, positive association with Internalizing scores (ORadj: 1.24, 95% CI: 1.02, 1.51). We observed a weak association between ΣOPECl and Total scores (Odds Ratio [OR] adjusted: 1.14, 95% Confidence Intervals [CI]: 0.97, 1.33) and null associations for ΣOPENCl. Associations were generally stronger among boys (ΣOPECl Total ORadj: 1.31, 95% CI: 1.02, 1.68). Visual summary of this manuscript, created with Microsoft PowerPoint.
IMPACT: Organophosphate esters (OPEs) are common aspects of our built environment and increasingly recognized as developmental neurotoxicants. Using data from a large Canadian birth cohort, we investigated associations between OPE exposures as measured in house dust postpartum and emotional and behavioral problems in children. We found that levels of two OPE compounds (tris(2-chloroethyl) phosphate and a component of Firemaster 550) were associated with increased odds of clinically relevant behavioral problems in early childhood. This important work underscores the urgent need for public health policies to limit the use of certain OPEs in consumer products to reduce children's exposure to harmful chemicals.
METHODS: We searched for publications that contained specific words regarding methanol poisoning in Scopus database.
RESULTS: A total of 912 articles, with 8,317 citations and with an average of 9.1 citations per document, were retrieved on methanol poisoning, and the bulk of the articles were published from the USA (20.9%), followed by Spain (4.4%), Canada (4.3%), India (3.1%), and France (3.0%). The articles were published belonging to 57 countries. No data related to methanol poisoning were published from 155 (73.1%) out of 212 countries. Twenty-one documents (2.3%) were published in Clinical Toxicology, whereas 18 (2.0%) were published in The Lancet.
CONCLUSIONS: Scientific production related to methanol poisoning is increasing. articles have been published in a wide range of journals with a variety of subject areas, most notably clinical toxicology; and the country with the greatest production was the USA.
OBJECTIVES: This study investigated DNAm differences associated with prenatal nitrogen dioxide (NO2) exposure (a surrogate measure of traffic-related air pollution) at birth and 1 y of age and examined their role in atopic disease. We focused on regions showing persistent DNAm differences from birth to 1 y of age and regions uniquely associated with postnatal NO2 exposure.
METHODS: Microarrays measured DNAm at birth and at 1 y of age for an atopy-enriched subset of Canadian Health Infant Longitudinal Development (CHILD) study participants. Individual and regional DNAm differences associated with prenatal NO2 (n=128) were identified, and their persistence at age 1 y were investigated using linear mixed effects models (n=124). Postnatal-specific DNAm differences (n=125) were isolated, and their association with NO2 in the first year of life was examined. Causal mediation investigated whether DNAm differences mediated associations between NO2 and age 1 y atopy or wheeze. Analyses were repeated using biological sex-stratified data.
RESULTS: At birth (n=128), 18 regions of DNAm were associated with NO2, with several annotated to HOX genes. Some of these regions were specifically identified in males (n=73), but not females (n=55). The effect of prenatal NO2 across CpGs within altered regions persisted at 1 y of age. No significant mediation effects were identified. Sex-stratified analyses identified postnatal-specific DNAm alterations.
DISCUSSION: Regional cord blood DNAm differences associated with prenatal NO2 persisted through at least the first year of life in CHILD participants. Some differences may represent sex-specific alterations, but replication in larger cohorts is needed. The early postnatal period remained a sensitive window to DNAm perturbations. https://doi.org/10.1289/EHP13034.