Abstract
Frog embryo teratogenesis assay—Xenopus (FETAX) was utilized as a model system to evaluate the effects on embryo-larval development at various low boron (B) exposure levels in the culture media. Concentrations tested ranged from <1 to 5000 μg B/L. A statistically significant (P < 0.05) increase in malformations was observed at ≤ 3 μg B/L, but not at the greater concentrations. Abnormal development of the gut, craniofacial region and eye, visceral edema, and kinking of the tail musculature (abnormal myotome development) and notochord were observed. In subsequent studies, adult frogs were maintained for 28 d on two diets: (1) low B (LB, 62 μg B/kg) or (2) boric acid supplemented (BA, 1851 μg B/kg); the frogs were subsequently mated, and their offspring were cultured in media containing various levels of B. Results of the 28-d depletion studies indicated that frogs maintained under LB conditions produced a greater proportion of (1) necrotic eggs and (2) fertilized embryos, which abnormally gastrulated at a greater rate and were substantially less viable than embryos from frogs fed the BA diet. Malformations similar to those seen in the initial study were observed in embryos from the B-depleted adults maintained in an LB environment; 28 d on the LB diet enhanced the incidence of malformations associated with the LB culture media. These abnormalities were not observed in embryos cultured in ≥4 μg B/L from adults cultured on the BA diet. These studies showed that insufficient B reproducibly interfered with normalXenopus laevis development during organogenesis, substantially impaired normal reproductive function in adult frogs, and thus represent the first studies demonstrating the nutritional essentiality of B in an amphibian species.
Similar content being viewed by others
References
F. J. Murray, A human health risk assessment of boron (boric acid and borax) in drinking water,Reg. Toxicol. Pharmacol. 22, 221–230 (1995).
F. H. Nielsen, The saga of boron in food: from a banished food preservative to a beneficial nutrient in for humans,Curr. Top. Plant Biochem. Physiol. 10, 274–286 (1991).
F. H. Nielsen, Facts and fallacies about boron,Nutr. Today 23, 6–12 (1992).
F. H. Nielsen, Biochemical and physiological consequences of boron deprivation in humans,Environ. Health Perspect. 102, 59–63 (1994).
W. Mertz, Essential trace metals: new definitions based on new paradigms,Nutr. Rev. 51, 287–291 (1993).
C. D. Hunt, The biochemical effects of physiologic amounts of dietary boron in animal nutritional models,Environ. Health Perspect. 102, 35–43 (1994).
J. N. Dumont, T. W. Schultz, M. Buchanan, and G. Kai, Frog embryo teratogenesis assay: Xenopus-a short-term assay applicable to complex mixtures, inSymposium on the Supplication of Short-Term Bioassays in the Analysis of Complex Environmental Mixtures III, M. D. Waters, S. S. Sandhu, J. Lewtas, L. Claxton, N. Chemoff, and S. Nesnow, eds., Plenum, New York, pp. 393–405 (1983).
D. J. Fort, D. A. Dawson, and J. A. Bantle, Evaluation of the development of a metabolic activation system for the frog embryo teratogenesis assay:Xenopus (FETAX), Teratogen.Carcinogen. Mutagen. 8, 251–263 (1988).
D. A. Dawson, D. J. Fort, G. L. Smith, D. L. Newell, and J. A. Bantle, Comparative evaluation of the developmental toxicity of nicotine and cotinine with FETAX,Teratogen. Carcinogen. Mutagen. 8, 329–388 (1988).
D. J. Fort, B. L. James, and J. A. Bantle, Evaluation of the developmental toxicity of five compounds with the frog embryo teratogenesis assay:Xenopus (FETAX),J. Appl. Toxicol. 9, 377–389 (1989).
D. J. Fort and J. A. Bantle, Use of frog embryo teratogenesis assay—Xenopus (FETAX) and an exogenous metabolic activation system to evaluate the developmental toxicity of diphenylhydantoin,Fundam. Appl. Toxicol. 14, 20–733 (1990).
D. J. Fort and J. A. Bantle, Analysis of the mechanism of isoniazid-induced developmental toxicity with frog embryo teratogenesis assay—Xenopus (FETAX),Teratogen. Carcinogen. Mutagen. 10, 463–476 (1990).
D. J. Fort, J. R. Rayburn, D. J. DeYoung, and J. A. Bantle, Assessing the efficacy of an Aroclor 1254-induced exogenous metabolic activation system for FETAX,Drug Chem. Toxicol. 14, 143–161 (1991).
D. J. Fort, J. R. Rayburn, and J. A. Bantle, Mechanisms of acetaminophen-induced developmental toxicityin vitro, Drug Chem. Toxicol. 15, 329–350 (1992).
D. J. Fort, E. L. Stover, J. R. Rayburn, M. A. Hull, and J. A. Bantle, Evaluation of the developmental toxicity of trichloroethylene and detoxification metabolites usingXenopus, Teratogen. Carcinogen. Mutagen. 13, 35–45 (1993).
D. J. Fort, E. L. Stover, T. L. Propst, and J. A. Bantle, Evaluation of the developmental toxicities of theophylline, dimethyluric acid, and methylxanthine metabolites using FETAX,Drug Chem. Toxicol. 19, 267–278 (1996).
D. J. Fort, E. L. Stover, T. L. Propst, M. A. Hull, and J. A. Bantle, Evaluation of the toxicities of coumarin, 4-hydroxycoumarin, and 7-hydroxycoumarin using FETAX,Drug Chem. Toxicol
G. Greenhouse, The evaluation of toxic effect of chemicals in fresh water by using frog embryos and larvae,Environ. Contam. Toxicol. 20, 93–95 (1978).
D. A. Dawson and J. A. Bantle, Development of a reconstituted water medium and initial validation of FETAX,J. Appl. Toxicol. 7, 237–244 (1987).
J. A. Bantle, D. A. Dawson, and D. J. Fort, Identification of developmental toxicants using the frog embryo teratogenesis assay—Xenopus (FETAX),Hydrobiologia 188/189, 577–585 (1989).
D. A. Dawson, D. J. Fort, D. L. Newell, and J. A. Bantle, Developmental toxicity testing with FETAX: evaluation of five validation compounds,Drug Chem. Toxicol. 12, 67–76 (1989).
J. A. Bantle, D. J. Fort, J. R. Rayburn, D. J. DeYoung, and S. J. Bush, Further validation of FETAX: evaluation of the development toxicity of five known mammalian teratogens and non-teratogens,Drug Chem. Toxicol. 13, 267–283 (1990).
D. J. DeYoung, J. A. Bantle, and D. J. Fort, Assessment of the developmental toxicity of ascorbic acid, sodium selenate, coumarin, serotonin and 13-cis retinoic acid using FETAX,Drug Chem. Toxicol. 14, 127–143 (1991).
Standard Guide for Conducting the Frog Embryo Teratogenesis Assay—Xenopus (FETAX), American Society for Testing and Materials (ASTM), E1439-91 (1991).
J. A. Bantle, J. N. Dumont, R. A. Finch, G. Linder, and D. J. Fort,Atlas of Abnormalities: A Guide for the Performance of FETAX, 2nd Ed., Oklahoma State University Press, Stillwater, Oklahoma (1998).
T. D. Sabourin and R. T. Faulk, Comparative evaluation of a short-term test for developmental effects using frog embryos, Branbury Report 26: Developmental Toxicology: Mechanisms and Risk, pp. 203–223 (1987).
C. L. Courchesne and J. A. Bantle, Analysis of the activity of DNA, RNA, and protein synthesis inhibitors onXenopus embryo development,Teratogen. Carcinogen. Mutagen. 5, 177–193 (1985).
J. N. Dumont, T. W. Schultz, and R. G. Epler, The response of the FETAX model to mammalian teratogens,Teratology 27, 39a (1983).
J. A. Bantle, D. J. Fort, and D. A. Dawson, Bridging the gap from short-term teratogenesis assays to human health hazard assessment by understanding common modes of teratogenic action, inProceedings of the 12th Aquatic Toxicology and Hazard Assessment: 12th vol., STM STP 1027, U. M. Cowgill and L. R. Williams, eds., American Society for Testing and Materials, Philadelphia, pp. 46–58 (1988).
D. J. Fort and E. L. Stover, Effect of low-level copper and pentachlorophenol exposure on various early life stages ofXenopus laevis, inProceedings of the Fifth Environmental Toxicology and Risk Assessment, ASTM STP 1306, D. A. Bengton and D. S. Henshel, eds., American Society for Testing and Materials, Philadelphia, pp. 188–203 (1996).
D. J. Fort and E. L. Stover, Development of short-term, whole embryo assays to evaluate detrimental effects on amphibian limb development and metamorphosis usingXenopus laevis, inProceedings of the Sixth Environmental Toxicology and Risk Assessment, ASTM STP 1317, F. J. Dwyer, T. R. Doane, and M. L. Hinman, eds., American Society for Testing and Materials, pp. 376–390 (1997).
D. J. Fort, T. L. Propst, T. Schetter, E. L. Stover, P. L. Strong, and F. J. Murray, Teratogenic effects of insufficient boron, copper, and zinc inXenopus, Teratology,57, 252 (1998).
C. D. Hunt, Dietary boron deficiency and supplementation, inTrace Elements in Laboratory Rodents, R. R. Watson, ed., CRC, Boca Raton, FL, pp. 229–253 (1996).
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Fort, D.J., Propst, T.L., Stover, E.L. et al. Adverse reproductive and developmental effects inXenopus from insufficient boron. Biol Trace Elem Res 66, 237–259 (1998). https://doi.org/10.1007/BF02783141
Published:
Issue Date:
DOI: https://doi.org/10.1007/BF02783141