A new study has found that many pregnant women in the United States have a number of potentially toxic or cancer-causing chemicals in their bodies.

In the study involving 268 women, researchers at the University of California, San Francisco (UCSF) analyzed data from the Centers for Disease Control and Prevention.

Study results show that almost all participants had detectable levels of eight types of chemicals in their blood or urine, including flame retardants and perchlorates found in rocket fuel.

Other chemicals include pesticides, car exhaust pollution, PCBs (toxic industrial chemical banned in 1979), PFCs (used in non- stick cookware), and phthalates (used in many fragrances and plastics).

Some of the chemicals detected in the study have been linked to health problems in other studies, finds the study.

The findings were published on Friday by USA Today.

Many of these chemicals pass through the placenta and can concentrate in the fetus, said lead author Tracey Woodruff, director of the UCSF's Program on Reproductive Health and Environment.

Other researchers have found some of these chemicals in babies' umbilical cords, according to Woodruff.

She called on Congress to pass tougher environmental laws to reduce such exposure.

But the American Chemistry Council (ACC), an industry group, said the findings aren't a cause for concern.

"As part of daily life, our bodies naturally absorb organic and man-made chemicals from our environments, and analytical advances now allow researchers to measure exceedingly minute traces of such substances," ACC spokesman Scott Jensen said in remarks published by USA Today.

Even the Centers for Disease Control and Prevention noted that the "mere presence of a chemical in the body does not mean that it will cause effects or disease," he said.