title: Recreational exposure to microcystins during algal blooms in two California lakes.
abstract: We conducted a study of recreational exposure to microcystins among 81 children and adults planning recreational activities on either of three California reservoirs, two with significant, ongoing blooms of toxin-producing cyanobacteria, including Microcystis aeruginosa (Bloom Lakes), and one without a toxin-producing algal bloom (Control Lake). We analyzed water samples for algal taxonomy, microcystin concentrations, and potential respiratory viruses (adenoviruses and enteroviruses). We measured microcystins in personal air samples, nasal swabs, and blood samples. We interviewed study participants for demographic and health symptoms information. We found highly variable microcystin concentrations in Bloom Lakes (<10 microg/L to >500 microg/L); microcystin was not detected in the Control Lake. We did not detect adenoviruses or enteroviruses in any of the lakes. Low microcystin concentrations were found in personal air samples (<0.1 ng/m(3) [limit of detection]-2.89 ng/m(3)) and nasal swabs (<0.1 ng [limit of detection]-5 ng). Microcystin concentrations in the water-soluble fraction of all plasma samples were below the limit of detection (1.0 microg/L). Our findings indicate that recreational activities in water bodies that experience toxin-producing cyanobacterial blooms can generate aerosolized cyanotoxins, making inhalation a potential route of exposure. Future studies should include collecting nasal swabs to assess upper respiratory tract deposition of toxin-containing aerosols droplets.
authors.affiliation: National Center for Environmental Health, Centers for Disease Control and Prevention, 4770 Buford Highway NE, MS F-57, Chamblee, GA 30341, USA. lbacker@cdc.gov
authors.forename: Lorraine C
authors.initials: LC
authors.lastname: Backer
authors.forename: Sandra V
authors.initials: SV
authors.lastname: McNeel
authors.forename: Terry
authors.initials: T
authors.lastname: Barber
authors.forename: Barbara
authors.initials: B
authors.lastname: Kirkpatrick
authors.forename: Christopher
authors.initials: C
authors.lastname: Williams
authors.forename: Mitch
authors.initials: M
authors.lastname: Irvin
authors.forename: Yue
authors.initials: Y
authors.lastname: Zhou
authors.forename: Trisha B
authors.initials: TB
authors.lastname: Johnson
authors.forename: Kate
authors.initials: K
authors.lastname: Nierenberg
authors.forename: Mark
authors.initials: M
authors.lastname: Aubel
authors.forename: Rebecca
authors.initials: R
authors.lastname: LePrell
authors.forename: Andrew
authors.initials: A
authors.lastname: Chapman
authors.forename: Amanda
authors.initials: A
authors.lastname: Foss
authors.forename: Susan
authors.initials: S
authors.lastname: Corum
authors.forename: Vincent R
authors.initials: VR
authors.lastname: Hill
authors.forename: Stephanie M
authors.initials: SM
authors.lastname: Kieszak
authors.forename: Yung-Sung
authors.initials: YS
authors.lastname: Cheng
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D002140:California; D002648:Child; D004781:Environmental Exposure / Q000032:analysis; D004784:Environmental Monitoring / Q000379:methods; D005260:Female; D005618:Fresh Water / Q000737:chemistry; D057097:Harmful Algal Bloom; D006801:Humans; D008297:Male; D052998:Microcystins / Q000009:adverse effects* / Q000032:analysis; D046931:Microcystis / Q000145:classification / Q000302:isolation & purification / Q000378:metabolism*; D008875:Middle Aged; D011998:Recreation / Q000502:physiology*; D014871:Water Microbiology; D014874:Water Pollutants, Chemical / Q000009:adverse effects* / Q000032:analysis; D055815:Young Adult
chemical_list: D052998:Microcystins; D014874:Water Pollutants, Chemical