Probabilistic risk evaluation for triclosan in surface water, sediments, and aquatic biota tissues.
Triclosan, an antimicrobial compound used in personal care products, occurs in the aquatic environment due to residual concentrations in municipal wastewater treatment effluent. We evaluate triclosan-related risks to the aquatic environment, for aquatic and sediment-dwelling organisms and for aquatic-feeding wildlife, based on measured and modeled exposure concentrations. Triclosan concentrations in surface water, sediment, and biota tissue are predicted using a fugacity model parameterized to run probabilistically, to supplement the limited available measurements of triclosan in sediment and tissue. Aquatic toxicity is evaluated based on a species sensitivity distribution, which is extrapolated to sediment and tissues assuming equilibrium partitioning. A probabilistic wildlife exposure model is also used, and estimated doses are compared with wildlife toxicity benchmarks identified from a review of published and proprietary studies. The 95th percentiles of measured and modeled triclosan concentrations in surface water, sediment, and biota tissues are consistently below the 5th percentile of the respective species sensitivity distributions, indicating that, under most scenarios, adverse affects due to triclosan are unlikely.
Lyndall
Jennifer
J
ENVIRON International Corporation, 13801 West Center Street, Suite 1, PO Box 405, Burton, Ohio 44021, USA. jlyndall@environcorp.com
Fuchsman
Phyllis
P
Bock
Michael
M
Barber
Timothy
T
Lauren
Darrel
D
Leigh
Katrina
K
Perruchon
Elyse
E
Capdevielle
Marie
M
D000821:Animal Feed / Q000032:analysis; D000818:Animals; D019985:Benchmarking; D058448:Biota; D054750:Ecotoxicology / Q000379:methods*; D004781:Environmental Exposure / Q000032:analysis; D020387:Food Chain; D019015:Geologic Sediments / Q000737:chemistry*; D008962:Models, Theoretical; D011336:Probability; D018570:Risk Assessment; D014260:Triclosan / Q000032:analysis / Q000378:metabolism / Q000633:toxicity*; D014867:Water / Q000737:chemistry*; D014874:Water Pollutants, Chemical / Q000032:analysis / Q000378:metabolism / Q000633:toxicity*
D014874:Water Pollutants, Chemical; D014867:Water; D014260:Triclosan