May Webinar: Title: The Hokkaido Study on Environment and Children’s Health: Overview and children’s chemical exposure assessment
May 17 @ 7:00 pm - 8:00 pm
The Hokkaido Study on Environment and Children’s Health is an ongoing study consisting of two birth cohorts of different sizes, the Sapporo cohort and the Hokkaido cohort, which were established in 2001. This presentation provides an update on the progress, summarize recent results, and suggest future directions. Prenatal environmental exposure to chemicals such as polychlorinated biphenyls (PCBs) and dioxins, organochlorine pesticides, per-and polyfluorinated compounds (PFAS), and phthalates has been measured. Cord blood biomarkers, such as adiponectin, leptin, thyroid, and reproductive hormones were also measured. Information on physical growth, neurodevelopment, allergy and infections, and onset of puberty has been collected to analyze health outcomes. In this webinar, results of children’s chemical exposure are focused. When participating children of the Hokkaido cohort reached 7 years old, morning void urine samples were collected to investigate the current internal exposure levels of shorter half-life compounds or their metabolites: phthalates, phosphate flame retardants and plasticizers (PFRs), bisphenols, and nonylphenol (NP). Using same samples, we measured oxidative stress 8-hydroxy-2’-deoxyguanosine and lipid peroxidation biomarkers N-ε-hexanoyl-lysine (HEL) and trans-4-hydroxy-2-nonenal (HNE). The prevalence of asthma and allergies were also examined by ISAAC questionnaire. When comparing the levels of these chemicals in the urine collected from 2012 to 2017, increasing secular trend of PFRs and BPS was found, while decreasing trend in BPA and NP. Furthermore, the levels of phthalates did not show any secular trends during the study periods suggesting stable exposures. Mixture of PFR metabolites as well as NP were positively associated with levels of HEL and HNE, whereas phthalates metabolites and bisphenol levels did not show any clear associations with these markers. Finally, single metabolite as well as mixture of phthalates were positively associated with increased risk of wheeze and eczema of 7 years old children. For further examination and follow-up, we are now conducting face-to face health check-up with blood and urine sample collections at one’s adolescence.
Presenter: Dr. Atsuko Ikeda-Araki, Hokkaido University
Atsuko Ikeda-Araki, Ph.D, is Professor of Faculty of Health Sciences, and adjunct Professor of Center for Environmental and Health Sciences (CEHS) at the Hokkaido University (HU). Her major is environmental epidemiology and got her Ph.D. in Graduate School of Medicine, HU. Atsuko‚Äôs interests focus on exposure to environmental chemicals (such as phthalate esters, PFAS, organophosphate flame retardants, bisphenol) and their effects on children‚Äôs health. She has also experience in indoor environmental quality and inhabitants‚Äô health studies. HU-CHES has been designated as World Health Organization (WHO) Collaborating Centre (CC) for Environmental Health and Prevention of Chemical Hazards since April 2015 and Atsuko is in charge of promoting international cooperation and actively collaborates with WHO and other WHOCC. Atsuko is an active member of ISES since 2012, and she received Travel Award (ISES Diversity Award) in 2019. She is also a member of ISEE, serves on the Editorial Board of Environment International, and Associate Editor of Journal of Occupational Health.