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Phthalate-organophosphate interactions: Toxicity, penetration, and metabolism studies with house flies

  • Mahdiy S. Al-Badry
  • Charles O. Knowles
Article

Abstract

Seventeen phthalates were not toxic to female house flies,Musca domestica L., when applied at high dosages topically or by injection. An antagonistic interaction was observed upon simultaneous application of di-2-ethylhexyl phthalate (DEHP) or di-n-butyl phthalate with 21 organophosphates. However, a synergistic interaction was apparent when house flies were pretreated with DEHP by topical application or injection 30 min prior to topical application of organophosphates. Penetration andin vivo andin vitro metabolism studies using DEHP and chlorpyrifos (O,O-diethyl0-(3,5,6-trichloro-2-pyridinyl) phosphorothioate) as model compounds indicated that DEHP, when applied topically to house flies, penetrated extremely slowly and was metabolized very slowly. DEHP also was shown to exert an inhibitory effect on chlorpyrifos metabolismin vitro andin vivo. Chlorpyrifos alone penetrated extremely rapidly and was rapidly metabolized. The antagonistic interaction may be due at least in part to the fact that both DEHP and chlorpyrifos are lipophilic, and the increase in the total lipophilic pool by the DEHP resulted in internal levels of toxicant below the toxicity threshold. A plausible explanation for the synergistic interaction is as follows. Chlorpyrifos penetrated slowly in DEHP pretreated house flies; however, the rate was not as slow as that observed when the two compounds were applied simultaneously. This coupled with the inhibition of chlorpyrifos metabolism by DEHP permitted a slow but lethal accumulation of toxicant.

Keywords

Toxicity Phthalate Model Compound DEHP Chlorpyrifos 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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References

  1. Carson, N. B., and G. W. Eddy: Preliminary evaluation of materials as synergists with pyrethrum against the body louse. J. Econ. Entomol.42, 694 (1949).Google Scholar
  2. Graham, P. R.: Phthalate ester plasticizers—why and how they are used. Environ. Health Persp.3, 3 (1973).Google Scholar
  3. Hoffman, R. A., T. L. Hopkins, and A. W. Lindquist: Tests with pyrethrum synergists combined with some organic phosphorus compounds against DDT-resistant flies. J. Econ. Entomol.47, 72 (1954).Google Scholar
  4. Hopkins, T. L., and R. A. Hoffman: Effectiveness of Dilan and certain candidate synergists against DDT-resistant house flies. J. Econ. Entomol.48, 146 (1955).Google Scholar
  5. Hutacharern, C., and C. O. Knowles: Toxicity and action of chlorpyrifos and other organophosphates in the eastern subterranean termite. J. Econ. Entomol.67, 721 (1974).Google Scholar
  6. Hutacharern, C., and C. O. Knowles: Metabolism of chlorpyrifos-14C in the eastern subterranean termite. Bull. Environ. Contam. Toxicol.13, 351 (1975).Google Scholar
  7. Jaeger, R. J., and R. J. Rubin: Plasticizers from plastic devices: extraction, metabolism and accumulation by biological systems. Science170, 460 (1970).Google Scholar
  8. Jaeger, R. J., and R. J. Rubin: Migration of phthalate ester plasticizer from polyvinyl chloride blood bags into stored human blood and its localization into human tissues. New Engl. J. Med.287, 1114 (1972).Google Scholar
  9. Knowles, C. O., and J. E. Casida: Mode of action of organophosphate anthelmintics. Cholinesterase inhibition inAscaris lumbricoides. J. Agr. Food Chem.14, 566 (1966).Google Scholar
  10. Mayer, F. J., Jr., D. L. Stalling, and J. L. Johnson: Phthalate esters as environmental contaminants. Nature238, 411 (1972).Google Scholar
  11. Mes, J., E. Coffin, and D. S. Campbell: Di-n-butyl and di-2-ethylhexyl phthalate in human adipose tissue. Bull. Environ. Contam. Toxicol.12, 721 (1974).Google Scholar
  12. Nazir, D. J., A. P. Alcaraz, B. A. Bierl, M. Beroza, and P. P. Nair: Isolation, identification and specific localization of di(2-ethylhexyl)phthalate in bovine heart muscle mitochondria. Biochem.10, 4228 (1971).Google Scholar
  13. Ogner, G., and M. Schnitzer: Humic substances: fulvic acid-dialkyl phthalate complexes and their role in pollution. Science170, 317 (1970).Google Scholar
  14. Sanders, H. O., F. L. Mayer, and D. F. Walsh: Toxicity, residue dynamics, and reproductive effects of phthalate esters in aquatic invertebrates. Environ. Res.6, 84 (1973).Google Scholar
  15. Sen Gupta, A. K., and C. O. Knowles: Metabolism ofN′-(4-chloro-o-tolyl)-N,N-dimethylformamidine by apple seedlings. J. Agr. Food Chem.17, 595 (1969).Google Scholar
  16. Stalling, D. L., J. W. Hogan, and J. L. Johnson: Phthalate ester residues-their metabolism and analysis in fish. Environ. Health Persp.3, 159 (1973).Google Scholar
  17. Taborsky, R. G.: Isolation studies on a lipoidal portion of the bovine pineal gland. J. Agr. Food Chem.15, 1073 (1967).Google Scholar
  18. Thomas, J. A., T. D. Darby, R. F. Wallin, P. J. Garvin, and L. Martis: A review of the biological effects of di-(2-ethylhexyl)phthalate. Toxicol. Appl. Pharmacol.45, 1 (1978).Google Scholar
  19. Weiden, M. H. J.: Insecticidal carbamoyloximes. J. Sci. Food Agri. Suppl. 19 (1968).Google Scholar
  20. Whitten, C. J., and D. L. Bull: Comparative toxicity, absorption, and metabolism of chlorpyrifos and its dimethyl homologue in methyl parathion-resistant and -susceptible tobacco budworms. Pesticide Biochem. Physiol.4, 266 (1974).Google Scholar

Copyright information

© Springer-Verlag New York Inc. 1980

Authors and Affiliations

  • Mahdiy S. Al-Badry
    • 1
  • Charles O. Knowles
    • 1
  1. 1.Department of EntomologyUniversity of MissouriColumbia

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