Potential arsenic exposures in 25 species of zoo animals living in CCA-wood enclosures

• Published in: The Science of the total environment 2016-05, Vol.551-552, p.614-621
• Main Authors: Gress, J., da Silva, E.B., de Oliveira, L.M., Zhao, Di, Anderson, G., Heard, D., Stuchal, L.D., Ma, L.Q.
• Format: Article
• Language: English
• Subjects: Animals; Animals, Zoo - metabolism; Arsenates - metabolism; Arsenic - metabolism; Biomarkers - metabolism; Birds; Callithrix; Chromated copper arsenate; Crocodilian; Endangered species; Environmental Exposure - analysis; Environmental Exposure - statistics & numerical data; Hazardous Substances - metabolism; Housing; Marmosets; Wood - chemistry; Zoo animals
• ISSN: 0048-9697; 1879-1026
• DOI: 10.1016/j.scitotenv.2016.02.065

Animal enclosures are often constructed from wood treated with the pesticide chromated copper arsenate (CCA), which leaches arsenic (As) into adjacent soil during normal weathering. This study evaluated potential pathways of As exposure in 25 species of zoo animals living in CCA-wood enclosures. We analyzed As speciation in complete animal foods, dislodgeable As from CCA-wood, and As levels in enclosure soils, as well as As levels in biomarkers of 9 species of crocodilians (eggs), 4 species of birds (feathers), 1 primate species (hair), and 1 porcupine species (quills). Elevated soil As in samples from 17 enclosures was observed at 1.0–110mg/kg, and enclosures housing threatened and endangered species had As levels higher than USEPA's risk-based Eco-SSL for birds and mammals of 43 and 46mg/kg. Wipe samples of CCA-wood on which primates sit had dislodgeable As residues of 4.6–111μg/100cm2, typical of unsealed CCA-wood. Inorganic As doses from animal foods were estimated at 0.22–7.8μg/kg bw/d. Some As levels in bird feathers and crocodilian eggs were higher than prior studies on wild species. However, hair from marmosets had 6.37mg/kg As, 30-fold greater than the reference value, possibly due to their inability to methylate inorganic As. Our data suggested that elevated As in soils and dislodgeable As from CCA-wood could be important sources of As exposure for zoo animals. [Display omitted] •Daily inorganic As dose from zoo animal foods was 0.22–7.8μg/kg bw/day.•Total As concentrations in soils of zoo animal enclosures were 1.0–110mg/kg.•Endangered zoo animals live in soils with As above USEPA Eco-SSLs for avian and mammal species.•Dislodgeable As on CCA-wood beams where primates sit was 4.6–111μg/100cm2.•Marmoset hair had 6.37mg/kg As compared to a reference value of 0.21mg/kg.