Letters from the September 25, 2004, issue of Science News

More of less is more

The counterintuitive finding that atrazine is more likely to kill tadpoles when it is highly diluted (“Just a Tad Is Too Much: Less is worse for tadpoles exposed to chemicals,” SN: 7/10/04, p. 20: Just a Tad Is Too Much: Less is worse for tadpoles exposed to chemicals) reminds me of a similar phenomenon in the alternative health care practice of homeopathy.