Effects of sediment-associated phenanthrene on survival, development and reproduction of two species of meiobenthic copepods

Abstract

The lethal and sublethal toxlclty of phendnthrene (a polycyclic aromatic hydrocarbon, PAH) to 2 species of meiobenthic estuarine harpacticoid copepods (Schfzopera knabeni dnd Nitocra lacustrfs) was ~nvestlgated Individuals of different life stages ( n a u p l~u s copepodite, adult male and female) were exposed to sediment-associated phenanthrene In separate 10 d bioassays Overall A' lacustns (10 d LCj, values ranglng from 43 to 105 pg g ' d~y wt) was more sensitive than S knabeni (10 d LCSD values ranging from 84 to 349 pg g ' dry \vt) Signlflcant differences In life-stage-speclfic sensitivity wele observed for S knabeni, with the nauplll belng most seniltive tolloived by copepodltes and adults, adult males and females \Yere equally sensltlve For N Iacustris females wele significantly more sensltlve than all other stages no s i g n~f~c a n t d~tferences \yere evldent among the other stages Phenanthrene effects on offspring productlon were invest~gated In the adult 10 d b~oassay Significant decreases in offspring productlon occurred at sublethal concentratlons for S knabenl (as low as 22 1-19 g.' d r y wt) but d t concentratlons In the same lange as the 10 d LC5,values for A' ldcustr~s In addition phenanthrene slgnlficantly prolonged embryonic and larval development and decreased e g g hatching success for both species Our results suggest that PAHs have a negative effect on the reprod u c t~o n of melobenthic copepods at sublethal concentrations mostly due to a decrease In brood prod u c t~o n rate and impalrlnent of hatchlng Overall, deleterious effects were manifested in the same range of concentratlons for both species but deflnite specles-spec~flc differences In the pattern of responses were evident

Determining the ecotoxicological mode of action of toxic chemicals in meiobenthic marine organisms: stage-specific short tests with Tisbe battagliai

“…Lotufo (1997Lotufo ( , 1998 after exposing 2 meiobenthic copepod species to sediment-associated fluoranthene over 10 and 14 d, respectively, found that sublethal effects on feeding and impairments of embryonic development occurred at lower concentrations than those causing adult mortality. Lotufo & Fleeger (1997) studying toxic effects of sediment-associated phenanthrene on different life-stages of meiobenthic copepods also reported higher sensitivities for naupliar stages.…”

“…In particular, meiobenthic copepods were exposed to aqueous and foodassociated fluoranthene, cypermethrin and deltamethrin. Fluoranthene is a polycyclic aromatic hydrocarbon (PAH) that is a common contaminant in many coastal systems, usually associated with discharge of petroleum and atmospheric depositions of combustion by-products (Kenish 1992, Lotufo & Fleeger 1997, Lotufo 1998. Insecticide pyrethroids such as cypermethrin and deltamethrin occur in marine coastal areas usually associated with agricultural runoff (Chandler et al 1994).…”

Mixtures of metals and polynuclear aromatic hydrocarbons elicit complex, nonadditive toxicological interactions in meiobenthic copepods

“…Of additional concern, adult S. knabeni, such as those used in the present bioassays, are very tolerant of phenanthrene compared to earlier life history stages. For example, significant effects of phenanthrene on reproductive output were detected at concentrations as low as 22 mg/kg dry sediment [45]. Therefore, if Cd-phenanthrene combinations exert a strong synergistic effect on reproduction in S. knabeni, effects would be expected to occur at much lower concentrations than for adult lethality.…”

Perylene Toxicity in the Estuarine Environment of Ria de Aveiro (Portugal)

“…The chronic toxicity assays in juveniles showed however that survival, growth and reproduction were all negatively affected by the added perylene. Lotufo and Fleeger (1997) also found negative effects of sub-lethal concentrations of PAH on the reproduction of meiobenthic estuarine copepods, mostly due to decreased rate of brood production and impairment of hatching.…”