Pregnant women can expect to hear from their doctors about the risks of everything from smoking to drinking to eating the wrong kind of fish or cheese.

What they won't often hear from their obstetrician? Potential dangers from toxic substances like solvents in our clothes and furniture, and heavy metals and pesticides.

A survey published Wednesday in the journal PLOS ONE that surveys 2,500 obstetrician found that almost 80 percent of doctors surveyed said that counseling could reduce risks of environmental toxins, but only 20 percent reported talking to their patients about it.

Reasons why ranged from creating anxiety, uncertainty about the evidence for harmful effects of chemicals, and worries that patients don't have ways to significantly avoid the toxic substances anyway.

Recent research has linked chemical flame retardants to cancer and brain damage in children, among other ailments, and the Centers for Disease Control also recommend that pregnant women avoid heavy metals and solvents, which can cause miscarriage, birth defects and developmental delays.

But there are so many chemicals — 84,000 in all — that are found in everything from our clothes to the food that we eat, that some doctors aren't sure what to tell patients.

"Providers were saying, 'If I bring this up with patients … it's going to raise anxiety and questions that I don't know how to deal with,’ ” Naomi Stotland, a professor of obstetrics at the University of California, San Francisco, and lead author on the study, told NPR. "There's a sense that, yes, these things may be harmful, but I don't know how to tell her how to reduce her risk."

It's also unclear just how much exposure really causes harm — if smaller amounts in our water and air, for example, affect us, or if they accumulate in the body in harmful ways.

However, it is known that chemicals are accumulating in our bodies. According to research published by the Environmental Defense Fund, phthalates and PBDE flame retardants are found in 99 percent of pregnant women in America, and 232 toxic chemicals are found in the umbilical cord blood of U.S. newborns.

Low-income mothers can be especially at risk for exposure to environmental toxins and their effects. A study from the National Institute of Health connected poorer birth outcomes for low-income mothers with an increased likelihood of exposure to air pollution.

Still, Stotland told NPR that there are simple, inexpensive steps that pregnant women can take, such as washing fruits and vegetables, using non-toxic cleaners and avoiding reheating food in plastic containers. She also said that if doctors get more information on environemtal toxins, they might feel more confident about giving advice to their patients.

Email: laneanderson@deseretnews.com