title: Nitrate-nitrogen levels in rural drinking water: Is there an association with age-related macular degeneration?
abstract: We examined the association of nitrate-nitrogen exposure from rural private drinking water and incidence of age-related macular degeneration (AMD). All participants in the Beaver Dam Eye Study (53916 improvement plan code) completed a questionnaire and had an ocular examination including standardized, graded fundus photographs at five examinations. Only information from rural residents in that study are included in this report. Data from an environmental monitoring study with probabilistic-based agro-chemical sampling, including nitrate-nitrogen, of rural private drinking water were available. Incidence of early AMD was associated with elevated nitrate-nitrogen levels in rural private drinking water supply (10.0% for low, 19.2% for medium, and 26.1% for high nitrate-nitrogen level in the right eye). The odds ratios (ORs) were 1.77 (95% confidence interval [CI]: 1.12-2.78) for medium and 2.88 (95% CI: 1.59-5.23) for high nitrate-nitrogen level. Incidence of late AMD was increased for those with medium or high levels of nitrate-nitrogen compared to low levels (2.3% for low and 5.1% for the medium or high nitrate-nitrogen level, for the right eye). The OR for medium or high nitrate-nitrogen groups was 2.80 (95% CI: 1.07-7.31) compared to the low nitrate-nitrogen group.
authors.affiliation: Department of Ophthalmology and Visual Sciences, University of Wisconsin School of Medicine and Public Health, Madison, Wisconsin 53726-2336, USA. kleinb@epi.ophth.wisc.edu
authors.forename: Barbara E K
authors.initials: BE
authors.lastname: Klein
authors.forename: Jane A
authors.initials: JA
authors.lastname: McElroy
authors.forename: Ronald
authors.initials: R
authors.lastname: Klein
authors.forename: Kerri P
authors.initials: KP
authors.lastname: Howard
authors.forename: Kristine E
authors.initials: KE
authors.lastname: Lee
mesh_terms: D000328:Adult; D000367:Age Factors; D000368:Aged; D015331:Cohort Studies; D060766:Drinking Water / Q000032:analysis*; D004781:Environmental Exposure; D004784:Environmental Monitoring; D005260:Female; D060587:Groundwater / Q000032:analysis; D006801:Humans; D015994:Incidence; D008268:Macular Degeneration / Q000139:chemically induced / Q000453:epidemiology*; D008297:Male; D008875:Middle Aged; D009566:Nitrates / Q000032:analysis / Q000633:toxicity*; D009584:Nitrogen / Q000032:analysis / Q000633:toxicity*; D012307:Risk Factors; D012424:Rural Population; D014874:Water Pollutants, Chemical / Q000032:analysis / Q000633:toxicity*; D014922:Wisconsin / Q000453:epidemiology
chemical_list: D060766:Drinking Water; D009566:Nitrates; D014874:Water Pollutants, Chemical; D009584:Nitrogen