Researchers argue for new ecotoxicity guidelines
Researchers from Hanyang University have discovered that Butylparaben, a widely used chemical preservative found in cosmetics, medical supplies and even food, is potentially harmful to the human body.
The research team from Hanyang University Industry-University Cooperation Foundation, led by Myungchan Gye and colleagues from the Korean Institute of Science and Technology (KIST), performed tests on amphibian embryos and found that the chemical is actually toxic to them.
When the researchers inserted frog embryos into products containing Butylparaben, it resulted in serious deformations in the developing embryos. In addition to Butylparaben, herbicides and insecticides like Atrazine and Carbaryl, alkylphenols like octylphenol and nonylphenol were also found to have possible adverse effects on organisms.
Likewise, ecotoxicity test guidelines are criterion to analyze the effect of chemicals included in medical supplies, cosmetic products, and in aquatic ecosystems. The ecotoxicity test employs other living organisms other than humans, evaluating the influence of chemicals on reproductive cells. It is to find the side effects and possible influences such as teratogens, which can cause congenital malfunctions. The establishment of ecotoxicity test guidelines with Korean amphibian embryos, which are from the indigenous frog species the Oriental Fire-bellied toad (Bombina Orientalis), recently showed results after 10 years of study.
"It is meaningful that the ecotoxicity test subjecting amphibian species' embryos, the highest organisms in this kind of research models was first done in Korea. Currently, most of the evaluation of manufactured products and quality of water are done only by following the physicochemical criteria. This kind of research can profoundly contribute to public health and hygiene," commented Gye.
There are two advantages to adopting this standard: drawing applicable data for the human body, and improving the conditions for experiments in the field. In the past, the majority of ecotoxicity tests were conducted through following the guidelines subjecting algae, fish, or water fleas. As such, there have been limitations in applying the test results to higher organisms like vertebrates.
Moreover, as the amphibian embryos initially are produced outside the body and also externally develop limbs and other crucial organs, they are easy to observe when conducting biological research. Worldwide, there are several eco-toxicity test guidelines established using amphibians. As the representative species, the frogs classified as Xenopus, tongueless frogs native to Africa, are most frequently used in the field.
The team established the ecotoxicity test guideline by analyzing microarray platform based on Oriental fire-bellied toad's genome sequence gained by employing degenerative PCR (polymerase chain reaction) and cDNA (complementary DNA) library. Not only that, the team carried out the research by analyzing and following protocols used in OECD TGs (test guideline) and the FETAX(Frog Embryo Teratogenesis Assay Xenopus) to standardize the results and ensure that skills needed can be uniform throughout nations. The newly invented technologies include standardized breeding technology of the Oriental fire-bellied toads and procedures to induce over-ovulation to four times per year to control the individual organisms.
The result of the study were published in Chemosphere in 2010, and were presented at several international academic conferences. Plus, two related patent applications are on the process. "Regarding the insufficient research made in this academic area in Korea and considering the importance in real life, there is need for a lot more effort. To keep up with advanced ecotoxicity test models which are used in the field, further investment and research effort is needed. With the developed guidelines and research technologies, our team will broaden the research find relations to public health and hygiene related with the aquatic environment; testing and evaluating the streams and rivers in Korea following the biological standards," said Gye.
Provided by Hanyang Univiversity
