The Human Early-Life Exposome (HELIX): Project Rationale and Design

http://dx.doi.org/10.1289/ehp.1307204



Table 1. Individual exposures.
Exposure group Entire cohorts
(n = 32,000)
HELIX subcohort
(n = 1,200)
Child Panel Study
(1 week in 2 seasons) (n = 150)
Pregnancy Panel Study
(1 week in 2 seasons) (n = 150)
Abbreviations: BP3, benzophenone-3; BPA, bisphenol A; BTEX, benzene, toluene, ethylbenzene, xylene; DBPs, disinfection by-products; DDE, dichlorodiphenyldichloroethylene; DEHP, di(2-ethylhexyl) phthalate; ETS, environmental tobacco smoke; HCB, hexachlorobenzene; Hg, mercury; NO2, nitrogen dioxide; OP, organophospate pesticides; Pb, lead; PBDE-47, polybrominated diphenyl ether–47; PCB-153, polychlorinated biphenyl–153; PFAS, perfluoroalkyl substances; PFBS, perfluorobutanesulfonic acid; PFHxS, perfluorohexane sulfonic acid; PFNA, perfluorononanoic acid; PFOA, perfluorooctanoic acid; PFOS, perfluorooctane sulfonic acid; TCS, triclosan; TMS, total metal spectrum.
aWhere measurements are available from previous studies, these will be used. bPooling of ≥ 2 urine samples when available.
PCB-153, DDE, HCB, PBDE-47 Biomarkers: in stored pregnancy blood samplesa and in newly collected child blood samples.
PFAS (PFOS, PFOA, PFBS, PFHxS, PFNA) Biomarkers: in stored pregnancy blood samplesa and in newly collected child blood samples. PBPK models for pregnancy and childhood.  
Metals (Hg, Pb, and TMS) Biomarkers: in stored pregnancy samplesa and in newly collected child samples: blood (Pb), urine (TMS), and hair (Hg).
Phthalates (13 metabolites) Biomarkers: in stored pregnancy urine samplesb and in newly collected child urine samples (last night and first morning void). Biomarkers: in daily repeat urine samples. Daily data on diet, cosmetics. PBPK model for DEHP. Biomarkers: in daily repeat urine samples. Daily data on diet, cosmetics. PBPK model for DEHP.
Phenols (BPA, parabens, TCS, BP3)   Biomarkers: in stored pregnancy urine samplesb and in newly collected child urine samples (last night and first morning void). Biomarkers: in daily repeat urine samples. Daily data on diet, cosmetics. Biomarkers: in daily repeat urine samples over whole week. Daily data on diet, cosmetics.
OP pesticides Biomarkers: in stored pregnancy urine samplesb and in newly collected child urine samples (last night and first morning void). Biomarkers: in daily repeat urine samples in two seasons. Daily data on diet and repellent use. Biomarkers: in daily repeat urine samples in two seasons. Daily data on diet and repellent use.
Water DBPs Estimates available from previous HiWATE project during and after pregnancy. New questionnaire in children on water consumption and swimming combined with water company data. Water consumption diaries. Water consumption diaries.
Indoor air: BTEX, NO2, PM2.5 Existing questionnaire data on indoor sources during and after pregnancy. New questionnaire in children on cooking, heating, cleaning, and ventilation. Passive BTEX and NO2 sampling in the home. Active PM2.5 sampling. Questionnaire on cooking, heating, cleaning, and ventilation. Passive BTEX and NO2 sampling in the home. Active PM2.5 sampling. Questionnaire on cooking, heating, cleaning, and ventilation.
ETS Existing questionnaire and cotinine data during and after pregnancy. New questionnaire in children. Biomarkers: cotinine measurement in newly collected child urine and/or hair samples. Questionnaire on ETS. Questionnaire on ETS.