The study was intended to collect data on children's exposure to household pesticides, and would have paid low-income families in Florida to record their use of pesticides and to videotape their children for purposes of later assessment.
The Environmental Protection Agency on Friday canceled a controversial study using children to measure the effect of pesticides after Democrats said they would block Senate confirmation of the agency's new head.
Stephen Johnson, as EPA's acting administrator, ordered an end to the planned study, a reversal from the agency's position just a day earlier when it said it would await the advice of outside scientific experts.
The aim of the study, Johnson said, was to fill data gaps on children's exposure to household pesticides and chemicals.
He suspended it last November after ethical questions were raised by scientists within the EPA and by environmentalists.
Over the study's two years, EPA had planned to give $970 plus a camcorder and children's clothes to each of the families of 60 children in Duval County, Florida, in what critics of the study noted was a low-income minority neighborhood.
EPA also had agreed to accept $2 million for the $9 million "Children's Health Environmental Exposure Research Study" from the American Chemistry Council, a trade group that represents chemical makers.
I am committed to ensuring that EPA's research is based on sound science with the highest ethical standards."
"I am very pleased that Mr. Johnson has recognized the gross error in judgment the EPA made when they concocted this immoral program to test pesticides on children," Boxer said.
On Thursday, the agency said it would await a report from a science advisory panel, a process that spokesman Rich Hood said could take until May, before deciding the study's fate.
The Senate Environment and Public Works Committee, which met on Wednesday to hear from Johnson, said Friday it would meet again next week to consider his nomination.