Comparison of population-level effects of heavy metals on fathead minnow (Pimephales promelas).
To evaluate the population-level effects of heavy metals (copper, zinc, cadmium, hexavalent chromium, nickel) on fathead minnow, Pimephales promelas, we first estimated the concentration-effect relationships between the metal concentrations and individual traits (juvenile survivability, hatchability, fertility) by using toxicity data collected from the literature. A Leslie matrix model of fathead minnow was used to calculate population growth rates from these relationships. The population threshold concentrations (PTCs) leading to zero net growth of the fish population were as follows: Cu, 27.4; Cd, 33.2; Zn (soft water), 81.5; Zn (hard water), 85.8; Ni, 504.8; Cr, 3251.6 (microg L(-1)). By comparing the PTCs with no observed effect concentrations (NOECs), we found that some PTCs were equivalent to or even lower than the corresponding NOECs. This result suggests that current ecological risk assessments based on the NOECs can be inadequate for protecting aquatic populations and more efforts on the population-level studies are needed.
Faculty of Environment and Information Sciences, Yokohama National University, 79-7, Tokiwadai, Hodogaya-ku, Yokohama, Kanagawa 240-8501, Japan. yuichiwsk@gmail.com
Yuichi
Y
Iwasaki
Takehiko I
TI
Hayashi
Masashi
M
Kamo
D000818:Animals; D003530:Cyprinidae / Q000254:growth & development*; D005260:Female; D005298:Fertility / Q000187:drug effects; D007928:Lethal Dose 50; D019216:Metals, Heavy / Q000032:analysis / Q000633:toxicity*; D008954:Models, Biological; D010063:Ovum / Q000187:drug effects / Q000254:growth & development; D011157:Population Dynamics; D018570:Risk Assessment; D014867:Water / Q000032:analysis; D014874:Water Pollutants, Chemical / Q000032:analysis / Q000633:toxicity*
D019216:Metals, Heavy; D014874:Water Pollutants, Chemical; D014867:Water