title: Early life low-level cadmium exposure is positively associated with increased oxidative stress.
abstract: Environmental exposure to cadmium (Cd) is known to induce oxidative stress, a state of imbalance between the production of reactive oxygen species (ROS) and the ability to detoxify them, in adults. However, data are lacking on potential effects in early-life. We evaluated urinary concentrations of 8-oxo-7,8-dihydro-2'-deoxyguanosine (8-oxodG), a recognized marker of oxidative DNA damage, in relation to Cd exposure in 96 predominantly breast-fed infants (11-17 weeks of age) in rural Bangladesh. Urinary 8-oxodG was measured using liquid chromatography tandem mass spectrometry and Cd in urine and breast milk by inductively coupled plasma mass spectrometry. Median concentration of 8-oxodG was 3.9 nmol/L, urinary Cd 0.30 μg/L, and breast-milk Cd 0.13 μg/L. In linear regression analyses, urinary 8-oxodG was positively associated with Cd in both urine (p=0.00067) and breast milk (p=0.0021), and negatively associated with body weight (kg; p=0.0041). Adjustment for age, body weight, socio-economic status, urinary arsenic, as well as magnesium, calcium, and copper in breast milk did not change the association between Cd exposure and urinary 8-oxodG. These findings suggest that early-life low-level exposure to Cd via breast milk induces oxidative stress. Further studies are warranted to elucidate whether this oxidative stress is associated with impaired child health and development.
authors.affiliation: Institute of Environmental Medicine, Karolinska Institutet, Box 210, SE-171 77 Stockholm, Sweden.
authors.forename: Maria
authors.initials: M
authors.lastname: Kippler
authors.forename: Mohammad Bakhtiar
authors.initials: MB
authors.lastname: Hossain
authors.forename: Christian
authors.initials: C
authors.lastname: Lindh
authors.forename: Sophie E
authors.initials: SE
authors.lastname: Moore
authors.forename: Iqbal
authors.initials: I
authors.lastname: Kabir
authors.forename: Marie
authors.initials: M
authors.lastname: Vahter
authors.forename: Karin
authors.initials: K
authors.lastname: Broberg
mesh_terms: D000080242:8-Hydroxy-2'-Deoxyguanosine; D001151:Arsenic / Q000633:toxicity / Q000652:urine; D001459:Bangladesh; D015415:Biomarkers / Q000652:urine; D002104:Cadmium / Q000633:toxicity / Q000652:urine*; D003430:Cross-Sectional Studies; D004249:DNA Damage; D003849:Deoxyguanosine / Q000031:analogs & derivatives / Q000652:urine; D004781:Environmental Exposure / Q000009:adverse effects* / Q000032:analysis; D004785:Environmental Pollutants / Q000633:toxicity / Q000652:urine*; D006801:Humans; D007223:Infant; D008895:Milk, Human / Q000737:chemistry; D018384:Oxidative Stress / Q000187:drug effects*; D012424:Rural Population
chemical_list: D015415:Biomarkers; D004785:Environmental Pollutants; D002104:Cadmium; D000080242:8-Hydroxy-2'-Deoxyguanosine; D003849:Deoxyguanosine; D001151:Arsenic