Eminent organic chemist Goverdhan Mehta was recently refused entry to the USA two weeks because his chemical expertise was deemed a threat to US security. The refusal to grant Mehta a US visa comes at the most inopportune time diplomatically speaking, given President Bush's imminent visit to India. Mehta is on record as being humiliated, accused of "hiding things" and being dishonest, and told that his work is dangerous because of its potential applications in chemical warfare, the Washington Post reports. Needless to say, the debacle has also caused major embarrassment to Mehta's American scientific colleagues. The consulate told Mehta "you have been denied a visa" and invited him to submit additional information, according to an official at the National Academy of Sciences who saw a copy of the document. Ironically, Mehta is president of the International Council for Science, an organization based in Paris whose aim is to facilitate collaboration between scientists internationally. The ICSU says Mehta is not alone and countless less well-known scientists are being refused US entry needlessly.