Synchrotron speciation of umbilical cord mercury and selenium after environmental exposure in Niigata

Monica Weng; Natalia V Dolgova; Linda I Vogt; Muhammad Qureshi; Dimosthenis Sokaras; Thomas Kroll; Hisashi Saitō; John L O'Donoghue; Gene E Watson; Gary J Myers; Tomoko Sekikawa; Ingrid J Pickering; Graham N George

doi:10.1016/j.neuro.2023.12.011

Synchrotron speciation of umbilical cord mercury and selenium after environmental exposure in Niigata

Neurotoxicology. 2024 Jan:100:117-123. doi: 10.1016/j.neuro.2023.12.011. Epub 2023 Dec 20.

Authors

Affiliations

¹ Department of Geological Sciences, University of Saskatchewan, 114 Science Place, Saskatoon, Saskatchewan S7N 5E2, Canada.
² Calibr - California Institute for Biomedical Research, Scripps Research, 10550 North Torrey Pines Road, La Jolla, CA 92037, USA.
³ Stanford Synchrotron Radiation Lightsource, SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, CA 94025, USA.
⁴ Kido Hospital, Niigata, Japan.
⁵ Department of Environmental Medicine, School of Medicine and Dentistry, University of Rochester, Rochester, NY, USA.
⁶ Department of Environmental Medicine, School of Medicine and Dentistry, University of Rochester, Rochester, NY, USA; Eastman Institute for Oral Health, School of Medicine and Dentistry, University of Rochester, Rochester, NY, USA.
⁷ Department of Environmental Medicine, School of Medicine and Dentistry, University of Rochester, Rochester, NY, USA; Departments of Neurology and Pediatrics, School of Medicine and Dentistry, University of Rochester, Rochester, NY, USA.
⁸ Department of Internal Medicine, Nuttari Clinic, 6-4-12 Nuttarihigasi, Chuo-ku, Niigata 950-0075, Japan.
⁹ Department of Geological Sciences, University of Saskatchewan, 114 Science Place, Saskatoon, Saskatchewan S7N 5E2, Canada; Toxicology Centre, University of Saskatchewan, Saskatoon, Saskatchewan, Canada; Department of Chemistry, University of Saskatchewan, Saskatoon, Saskatchewan, Canada.
¹⁰ Department of Geological Sciences, University of Saskatchewan, 114 Science Place, Saskatoon, Saskatchewan S7N 5E2, Canada; Toxicology Centre, University of Saskatchewan, Saskatoon, Saskatchewan, Canada; Department of Chemistry, University of Saskatchewan, Saskatoon, Saskatchewan, Canada. Electronic address: [email protected].

Abstract

The insidious and deadly nature of mercury's organometallic compounds is informed by two large scale poisonings due to industrial mercury pollution that occurred decades ago in Minamata and Niigata, Japan. The present study examined chemical speciation for both mercury and selenium in a historic umbilical cord sample from a child born to a mother who lived near the Agano River in Niigata. The mother had experienced mercury exposure leading to more than 50 ppm mercury measured in her hair and was symptomatic 9 years prior to the birth. We sought to determine the mercury and selenium speciation in the child's cord using Hg Lα1 and Se Kα1 high-energy resolution fluorescence detected X-ray absorption spectroscopy, the chemical speciation of mercury was found to be predominantly organometallic and coordinated to a thiolate. The selenium was found to be primarily in an organic form and at levels higher than those of mercury, with no evidence of mercury-selenium chemical species. Our results are consistent with mercury exposure at Niigata being due to exposure to organometallic mercury species.

Keywords: High-energy resolution fluorescence detected X-ray absorption spectroscopy; Mercury; Minamata; Neurotoxicology; Niigata; Selenium; Stem cell; Synchrotron light; Umbilical cord.

MeSH terms

Child
Environmental Exposure
Female
Humans
Mercury Poisoning*
Mercury* / analysis
Methylmercury Compounds*
Selenium*
Synchrotrons

Substances

Mercury
Selenium
Methylmercury Compounds