Toxicokinetics and Toxicodynamics of Pyrethroid Insecticides in Fish

Abstract

The pyrethroid insecticides are extremely toxic to fish, with 96-h LC50 values generally below 10 pg/L and i.p. and i.v. LD50 values below 20 mg/kg. Corresponding LD5O values in mammals and birds are in the range of several hundred to several thousand milligrams per kilogram. This review examines pyrethroid toxicokinetics and toxicodynamics in fish as critical factors associated with species selectivity. Studies with permethrin, cypermethrin and fenvalerate have established that rates of metabolism and elimination in rainbow trout are significantly lower than those reported for birds and mammals. Comparatively low lethal brain pyrethroid concentrations and nonneural aspects of pyrethroid intoxication in fish suggest that variations in toxicodynamics are also crucial in evaluating pyrethroid selectivity.

Survival of Bluegill and Their Behavioral Responses During Continuous and Pulsed Exposures to Esfenvalerate, a Pyrethroid Insecticide

“…The responses among exposed bluegill in the present study were consistent with the behavioral aMeans are significantly different from the pulse 2 mean for that treatment. symptoms reported for rainbow trout exposed to esfenvalerate, including initial hyperexcitability followed by tonic seizures that included head shaking and violent whole-body contractions [20,21]. Body tremors were a highly sensitive indication of esfenvalerate toxicity in bluegill and occurred consistently among all treatments exposed to 0.025 pg/L and higher during pulsed exposures.…”

Genotoxic and oxidative stress‐inducing effects of deltamethrin in the erythrocytes of a freshwater biomarker fish species, Channa punctata Bloch

“…However, data are now accumulating on the toxic effects of pyrethroids including their mutagenic, teratogenic, and carcinogenic effects in mammalian and nonmammalian species (Chauhan et al, 2007;Herrera and Laborda, 1988;Patel et al, 2006;Toś-Luty et al, 2001). Pyrethroids have shown relatively higher toxicity in aquatic organisms (Bradbury and Coats, 1989;Paul et al, 2005;Sayeed et al, 2003;Smith and Stratton, 1986). Fish, in particular, appear to be highly sensitive to pyrethroids (Bradbury and Coats, 1989;Haya, 1989;Paul et al, 2005;Sayeed et al, 2003).…”

“…Pyrethroids have shown relatively higher toxicity in aquatic organisms (Bradbury and Coats, 1989;Paul et al, 2005;Sayeed et al, 2003;Smith and Stratton, 1986). Fish, in particular, appear to be highly sensitive to pyrethroids (Bradbury and Coats, 1989;Haya, 1989;Paul et al, 2005;Sayeed et al, 2003). One of the devastating effects of pyrethroids in fishes is the oxidative stress inducing effects causing peroxidative damages to vital tissues such as gills Sayeed et al, 2003).…”

Structure‐Toxicity Relationships for α, β‐Unsaturated Alcohols in Fish

“…19 and 20, Table 1) as non-reactive, narcotic chemicals, the toxicity for which were accurately predicted by the QSAR for narcosis [3]. Although Bradbury and Christensen [4] found that the allylic alcohols were activated in v i m , the reactivity of the metabolites was seemingly insufficient to cause measurable excess toxicity in vivo. Since the 3-hexene-1-01 isomers can be metabolized to aldehydes but not to a$unsaturated carbonyls, the in vitro enzyme inhibition [4] could be due to the carbonyl reactivity alone.…”

“…Although Bradbury and Christensen [4] found that the allylic alcohols were activated in v i m , the reactivity of the metabolites was seemingly insufficient to cause measurable excess toxicity in vivo. Since the 3-hexene-1-01 isomers can be metabolized to aldehydes but not to a$unsaturated carbonyls, the in vitro enzyme inhibition [4] could be due to the carbonyl reactivity alone. This would also be consistent with other observations that, as the hydrophobicity of aldehydes increases, the toxic effects in vivo more closely resemble those of narcotics than those of electrophiles [6].…”