Amy Ellis Nutt does a major take-out on the links between agricultural use of antibiotics and the emergence of antibiotic resistant strains of bacteria that can threaten human health. She chooses as a case in point the industrial-scale chicken growing operations of the Delaware-Maryland-Virginia peninsula. Growers of chickens and other animals use antibiotics not merely to treat disease outbreaks, but to promote growth and convert feed to meat more efficiently. Much of the antibiotics added to feed is not metabolized and ultimately excreted in feces. It ends up in the soil, water, and air. Nutt gives a graphic sense of the germ-laden dust which is part of the environment of a chicken farm -- by telling the stories of the chicken-catchers who work in the coops all day, and of their chronic illnesses. The account is a thorough and balanced one, citing numerous scientific studies and authorities both raising alarm about antibiotics and downplaying the immediacy of the threat. She raises the questions of whether consumers are told enough about antibiotics going into their food and whether the Food and Drug Administration is doing enough to monitor and regulate them. (See: http://www.nj.com/news/ledger/index.ssf?/base/news-12/1070863848273990.xml.)