WASHINGTON — The Environmental Protection Agency is setting the first federal drinking water standard for a toxic rocket fuel ingredient linked to thyroid problems in pregnant women and young children, the Obama administration announced on Wednesday.

Environmental Protection Agency administrator Lisa Jackson said that setting the standard will protect public health and spark new technologies to clean up drinking water. Based on monitoring conducted from 2001 to 2005, 153 drinking water sources in 26 states contain perchlorate. The standard could take up to two years to develop, the EPA said.

Perchlorate is also used in fireworks and explosives. In most cases, water contamination has been caused by improper disposal at rocket testing sites, military bases and chemical plants.

"As improved standards are developed and put in place . clean water technology innovators have an opportunity to create cutting edge solutions that will strengthen health protections and spark economic growth," Jackson said in a statement.

Jackson is expected to make that case before a Senate panel Wednesday, where she will likely face opposition from Republicans who plan to take on the EPA over air pollution regulations, controls on the gases blamed for global warming, and other regulations. Oklahoma Sen. James Inhofe, the top Republican on the environment panel, will bring forward legislation Wednesday to strip the agency of its ability to control heat-trapping gases under the Clean Air Act. House Energy and Commerce Chairman Fred Upton, R-Mich., will release an identical draft bill.

Democrats, who have pushed for the EPA to regulate perchlorate, say the decision shows the administration standing up for rules that protect public health, even if they burden business. President Barack Obama recently announced a review of all regulations to reduce barriers to economic growth and investment.

The perchlorate standard is eight years in the making. In 2002, an EPA draft risk assessment found that 1 part per billion should be considered safe. Six years later, the Bush administration decided not to regulate the chemical, instead recommending that concentrations not exceed 15 parts per billion. At the time, federal scientists estimated that 16.6 million Americans could be exposed to unsafe levels through their drinking water.

California and Massachusetts in the meantime have set state-level drinking water standards.

Sen. Barbara Boxer, D-Calif., who has sponsored legislation to require the EPA to set a standard, said in a statement Wednesday that she was pleased the government was "finally going to protect our families from perchlorate." California has the most water supplies affected — 58, according to the 2001-05 data. Many of the others are in Texas.

"I will do everything I can to make sure this new protection moves forward," Boxer said.

Pentagon officials have spent years questioning the EPA's assessment of perchlorate's risk but have denied influencing the agency's decisions. The military could face liability for tainting water during rocket and missile testing, since the standard will force water agencies around the country to clean up the pollution.

• EPA's perchlorate website: http://tinyurl.com/EPAperchlorate