Ed Darrell has been working his way through Steve Milloy’s 100 things about DDT. See if you can spot what Milloy did in number 10. Here’s Milloy:
[Rachel Carson wrote] “Quail into whose diet DDT was introduced throughout the breeding season survived and even produced normal numbers of fertile eggs. But few of the eggs hatched.” DeWitt’s 1956 article (in Journal of Agriculture and Food Chemistry) actually yielded a very different conclusion. Quail were fed 200 parts per million of DDT in all of their food throughout the breeding season. DeWitt reports that 80% of their eggs hatched, compared with the “control” birds which hatched 83.9% of their eggs.
And here’s the full quote from Carson:
quail into whose diet DDT was introduced throughout the breeding season survived and even produced normal numbers of fertile eggs. But few of the eggs hatched. “Many embryos appeared to develop normally during the early stages of incubation, but died during the hatching period,” Dr. DeWitt said. Of those that did hatch, more than half died within 5 days.
And here’s DeWitt’s abstract:
Egg production, fertility, and hatchability were relatively unaffected by inclusion of insecticides in diets fed breeding quail, but chicks from these matings showed high mortality rates even when reared on insecticide-free diets.
Go read Ed Darrell for the answer and more detail.