When science students at Ithaca High School wondered if chemicals proposed for de-icing snow-covered hills in their hometown really were environmentally safer than road salt, they didn't take the word of manufacturers and government officials but began testing the chemicals themselves. Nearby, in Moravia, N.Y., high school students doubling as volunteer firefighters became concerned that foaming chemicals used to extinguish blazes might harm plants and animals. They, too, didn't take the official word but designed their own laboratory experiments.
Now, the experimental protocols tested by these high school students, in collaboration with Cornell University researchers and science educators, are available to students and teachers nationwide with the publication of the first curriculum in the Cornell Scientific Inquiry Series, "Assessing Toxic Risk."
"Too often, school sciences are presented as discrete fields with few interconnections," says Nancy M. Trautmann, a senior research associate in the Cornell Center for the Environment and lead author of the first in a planned series of four environment-related curricula. "We think toxicology provides a natural link between scientific disciplines – including biology, chemistry, environmental science and human health – to focus the students' attention on some real scientific questions in their own communities."
She adds, "Of course not all these students will go on to be professional scientists, but they will all be citizens. One of our goals in the Cornell Environmental Inquiry program is to help students become better decision-makers on scientific matters by developing an understanding of what the process of scientific inquiry entails. Learning how scientists assess toxic risk – which is something many adults and policy-makers don't fully understand – seemed like a good place to start." Development of the Scientific Inquiry Series, funded by the National Science Foundation's Instructional Materials Development Program and by Cornell University, began with Cornell researchers opening their laboratories to high school teachers and students from across New York state. Subsequent curricular publications in the series will help high school students conduct and interpret experiments in the ecology of invasive species, watershed science and the natural processes of decay and renewal. Materials are distributed through the publishing arm of the National Science Teachers Association, NSTA Press.
The experimental procedures taught to students are not costly to conduct, says Trautmann, mindful that most schools have limited budgets for laboratory equipment and supplies. For example, the bioassays recommended to assess toxicity of possible environmental threats, such as de-icing chemicals, involve inexpensive organisms such as lettuce seeds, water fleas called Daphnia and duckweed, a common aquatic plant that can be gathered from local ponds or ordered from biological supply companies.
Like laboratory rats, these organisms are exposed to different concentrations of toxic substances as students learn to conduct dose/response experiments and test the effect of environmental samples, such as the petroleum-laced runoff from parking lots. Professional toxicologists do the same thing, using some of the same bioassay techniques, Trautmann notes.
Another aspect of research is peer review by scientific colleagues, either to examine requests for public funding for research or to review scientific reports in academic journals. The Cornell Scientific Inquiry program provides similar peer review experiences for students, either in person or using a web-based system developed for anonymous exchange of critiques among students who have carried out bioassay experiments.
In many cases, the final step is reporting research results to the community. The Ithaca High School students who studied highway de-icing alternatives reported to the city department of public works that there is no easy solution – the chemical that proved the most environmentally friendly was also the least cost-effective means of melting highway ice.
The fire-fighting foam turned out to be relatively harmless, the Moravia High School students were able to tell their fire chief. Their teacher reported that the youthful volunteers were "fired up" by the chance to perform science experiments of relevance to the community.