US EPA

3055858 

Journal Article 

Prenatal particulate air pollution and neurodevelopment in urban children: Examining sensitive windows and sex-specific associations 

Chiu, YM; Hsu, HL; Coull, BA; Bellinger, DC; Kloog, I; Schwartz, J; Wright, RO; Wright, RJ 

2016 

1 

Environment International
ISSN: 0160-4120
EISSN: 1873-6750 

87 

56-65 

English 

26641520 

10.1016/j.envint.2015.11.010 

WOS:000368951700007 

BACKGROUND: Brain growth and structural organization occurs in stages beginning prenatally. Toxicants may impact neurodevelopment differently dependent upon exposure timing and fetal sex.

OBJECTIVES: We implemented innovative methodology to identify sensitive windows for the associations between prenatal particulate matter with diameter≤2.5μm (PM2.5) and children's neurodevelopment.

METHODS: We assessed 267 full-term urban children's prenatal daily PM2.5 exposure using a validated satellite-based spatio-temporally resolved prediction model. Outcomes included IQ (WISC-IV), attention (omission errors [OEs], commission errors [CEs], hit reaction time [HRT], and HRT standard error [HRT-SE] on the Conners' CPT-II), and memory (general memory [GM] index and its components - verbal [VEM] and visual [VIM] memory, and attention-concentration [AC] indices on the WRAML-2) assessed at age 6.5±0.98years. To identify the role of exposure timing, we used distributed lag models to examine associations between weekly prenatal PM2.5 exposure and neurodevelopment. Sex-specific associations were also examined.

RESULTS: Mothers were primarily minorities (60% Hispanic, 25% black); 69% had ≤12years of education. Adjusting for maternal age, education, race, and smoking, we found associations between higher PM2.5 levels at 31-38weeks with lower IQ, at 20-26weeks gestation with increased OEs, at 32-36weeks with slower HRT, and at 22-40weeks with increased HRT-SE among boys, while significant associations were found in memory domains in girls (higher PM2.5 exposure at 18-26weeks with reduced VIM, at 12-20weeks with reduced GM).

CONCLUSIONS: Increased PM2.5 exposure in specific prenatal windows may be associated with poorer function across memory and attention domains with variable associations based on sex. Refined determination of time window- and sex-specific associations may enhance insight into underlying mechanisms and identification of vulnerable subgroups. 

Air pollution; Prenatal exposure; Particulate matter; Neurodevelopment; Sensitive windows; Sex-specific associations