POLLUTION AND WASTE MANAGEMENT To efficiently overcome pollution, we could use engineered microorganisms with altered biochemical or metabolic pathways to degrade environmentally toxic compounds. Enhanced phytoreme- diation of toxic and heavy metals from the environment, through the assistance of engineered microorganisms, could facili- tate the treatment of polluted soil and water on a large scale. Bipin Singh Center for Computational Natural Sciences and Bioinformatics (CCNSB), International Institute of Information Technology (IIIT), Hyderabad, Hyderabad, Telangana, 500032, India. Email: bipin.singh@research.iiit.ac.in When a chemical has risk potential, chem- ists can formulate similar chemicals without negative health and environmental implica- tions. Disposal of a chemical must involve a regenerative cycle rather than a destination, lest that destination become dangerously close in proximity to our living spaces. Rose Joy Crocker Adelaide, South Australia, 5022, Australia. Email: rose.crocker@me.com Scientists have proposed the use of molec- ular sponges to purify land and sea vehicle emissions, to filter the emissions of large- scale industry, and to passively generate water using the humidity and temperature differences between day and night. Timothy Easun School of Chemistry, Cardi University, Cardi, CF10 3AT, UK. Email: easuntl@cardi.ac.uk The inside of factory pipelines can be coated with chemical materials to react with the waste moving through them and produce environmentally friendly materials. Water treatment with suitable chemical materials can allow water to be 886 20 MAY 2016 • VOL 352 ISSUE 6288 sciencemag.org SCIENCE PHOTO: SEAN PAVONE/ISTOCK PHOTO INSIGHTS INGENUITY: NEXTGEN’S VISION Edited by Jennifer Sills LETTERS Full speed ahead to the City on the Hill We asked young scientists from a variety of fields this question: According to the United Nations (http://esa.un.org/unpd/wup/), more than two-thirds of the human population will live in cities by 2050. How can scientists in your field help society prepare for an increasingly urbanized world? Excerpts of our panel’s proposed contributions follow, catego- rized by the challenges they address. For responses that span categories, we have printed the author’s name with the first excerpt and initials thereafter. Read the full responses, and many more, at scim.ag/UPInGen. Follow Science’s InGenuity on Twitter with the hashtag #InGenSci ONLINE Published by AAAS on May 19, 2016 http://science.sciencemag.org/ Downloaded from