Studies on the Synergistic Effect of Piperonyl Butoxide and Isobutylundecyleneamide on Pyrethrins and Allethrin

Abstract

Experiments are described to compare the toxicity of natural pyrethrins and allethrin, the completely synthetic homologue of cinerin I, and to show the effect of the two synergists, piperonyl butoxide and iaobutyl undecyleneamide (IN 930) on both these active ingredients, using a measured‐drop technique with Mucca domestiur L. the housefly, and a residual‐film technique with Cimex lectularius L. the bed bug. In the conditions of the experiment, pyrethrins were shown to be twice as toxic as allethrin to flies, and 5.5 times as toxic as allethrin to bugs. The two synergists were tested at several ratios to the two insecticides, ranging from 1 : 1 to 20 : 1. The results were plotted as series of log. concentration/probit regression linea. These were parallel for the bug tests; but in the fly tests, the slope of the line increased with a rise in the proportion of Synergist to insecticide. The estimated median lethal concentrations indicated, in all cases, that the toxicity increased with a rise in the ratio of synergist to insecticide, at least up to 20 : 1. However, the enhancement of toxicity was greatest for the smaller ratios and fell off as the ratio increased. Piperonyl butoxide was the more powerful synergist, increasing the potency of pyrethrins 5 times and allethrin 4 times to flies, and pyrethrins twice and allethrin 3 times to bugs, whereas IN 930 did not increase the potency of either ingredient more than twice to either test insect.The addition of piperonyl butoxide to residual films of pyrethrins greatly prolonged their effectiveness; but an experiment designed to investigate the effect of the synergist on the stability of this insecticide showed that this action, if it exists, must be slight.

Whole‐sediment toxicity identification evaluation tools for pyrethroid insecticides: I. Piperonyl butoxide addition

“…Not only do these higher concentrations raise concerns regarding toxicity of the PBO itself when used with H. azteca , they also carry a substantial risk of false‐positive responses. The increase in pyrethroid toxicity achieved is a function of the log of the PBO concentration [30]. The greater the PBO concentration, the less pyrethroid needed to see a PBO‐mediated enhancement in toxicity.…”

“…Therefore, some species may be inappropriate for use with the PBO addition method. Use of PBO with the oligochaete Lumbriculus variegatus in the presence of organophosphates did not cause the expected decrease in toxicity, presumably because of limited MFO biotransformation in this species [30]. Mollusks in general have relatively limited xenobiotic metabolism as well [34], making them useful for bioaccumulation studies but, potentially, not in TIEs with PBO addition.…”

Ecofriendly synthesis, antimicrobial and antispermatogenic activity of triorganotin(IV) complexes with 4′‐nitrobenzanilide semicarbazone and 4′‐nitrobezanilide thiosemicarbazone

“…The greater toxicity of the complexes than the bases can also be explained by the greater lipophilic character of the complexes. [57] It has also been observed www.interscience.wiley.com/journal/aoc that the toxicity of the ligands and their complexes decreases on lowering the concentration. From the data obtained it is evident that some of these complexes exhibit a good activity against the tested organisms but specially significant is the complex [(n-C 4 H 9 -) 3 Sn(L 2 )], which showed the highest activity among the complexes possibly due to the difference in sulfur content and highest lipophilic nature of tri-n-butyltin(IV) complex.…”

Whole sediment Toxicity Identification Evaluation tools for pyrethroid insecticides: I. Piperonyl butoxide addition

“…Not only do these higher concentrations raise concerns regarding toxicity of the PBO itself when used with H. azteca, they also carry a substantial risk of false-positive responses. The increase in pyrethroid toxicity achieved is a function of the log of the PBO concentration [30]. The greater the PBO concentration, the less pyrethroid needed to see a PBOmediated enhancement in toxicity.…”