TY - JOUR
T1 - Passive dosing of polycyclic aromatic hydrocarbon (PAH) mixtures to terrestrial springtails
T2 - Linking mixture toxicity to chemical activities, equilibrium lipid concentrations, and toxic units
AU - Schmidt, Stine N.
AU - Holmstrup, Martin
AU - Smith, Kilian E.C.
AU - Mayer, Philipp
PY - 2013
Y1 - 2013
N2 - A 7-day mixture toxicity experiment with the terrestrial springtail Folsomia candida was conducted, and the effects were linked to three different mixture exposure parameters. Passive dosing from silicone was applied to tightly control exposure levels and compositions of 12 mixture treatments, containing the polycydic aromatic hydrocarbons (PAlis) naphthalene, phenanthrene, and pyrene. Springtail lethality was then linked to sum chemical activities (Sigma a), sum equilibrium lipid concentrations (Sigma C-lipid eq.), and sum toxic units (Sigma TU). In each case, the effects of all 12 mixture treatments could be fitted to one sigmoidal exposure response relationship. The effective lethal chemical activity (La-50) of 0.027 was well within the expected range for baseline toxicity of 0.01-0.1. Linking the effects to the lipid based exposure parameter yielded an effective lethal concentration (Sigma C-lipid eq. 50) of 133 mmol kg(-1) lipid in good correspondence with the lethal membrane burden for baseline toxicity (40-160 mmol kg(-1) lipid). Finally, the effective lethal toxic unit (Sigma TU50) of 1.20 was rather close to the expected value of 1. Altogether, passive dosing provided tightly controlled mixture exposure in terms of both level and composition, while Sigma a, Sigma C-lipid eq., and Sigma TU allowed baseline toxicity to be linked to mixture exposure.
AB - A 7-day mixture toxicity experiment with the terrestrial springtail Folsomia candida was conducted, and the effects were linked to three different mixture exposure parameters. Passive dosing from silicone was applied to tightly control exposure levels and compositions of 12 mixture treatments, containing the polycydic aromatic hydrocarbons (PAlis) naphthalene, phenanthrene, and pyrene. Springtail lethality was then linked to sum chemical activities (Sigma a), sum equilibrium lipid concentrations (Sigma C-lipid eq.), and sum toxic units (Sigma TU). In each case, the effects of all 12 mixture treatments could be fitted to one sigmoidal exposure response relationship. The effective lethal chemical activity (La-50) of 0.027 was well within the expected range for baseline toxicity of 0.01-0.1. Linking the effects to the lipid based exposure parameter yielded an effective lethal concentration (Sigma C-lipid eq. 50) of 133 mmol kg(-1) lipid in good correspondence with the lethal membrane burden for baseline toxicity (40-160 mmol kg(-1) lipid). Finally, the effective lethal toxic unit (Sigma TU50) of 1.20 was rather close to the expected value of 1. Altogether, passive dosing provided tightly controlled mixture exposure in terms of both level and composition, while Sigma a, Sigma C-lipid eq., and Sigma TU allowed baseline toxicity to be linked to mixture exposure.
U2 - 10.1021/es3047813
DO - 10.1021/es3047813
M3 - Journal article
C2 - 23473585
SN - 0013-936X
VL - 47
SP - 7020
EP - 7027
JO - Environmental Science & Technology
JF - Environmental Science & Technology
IS - 13
ER -