Good news for new and soon-to-be moms! A mother's breast milk may not be as toxic for her baby as she once thought!

PCBs, or polychlorinated biphenols, are a group of industrial chemicals that were developed in the early 1920s and used as coolants and lubricants for various electrical equipment. But by the 1970s, most health organizations recognized PCBs are probable carcinogens that were damaging both to the environment and to human health. The use of PCBs was banned in Sweden in 1972 (PCBs have been banned in the U.S. since 1979) but traces remain in the environment due to the long degradation process. One place these traces have been showing up: a mother's breast milk. But good news is on the horizon..these traces may finally be declining.

In a recent study published in Sweden's Uppsala Nya Tidning (UNT), researchers analyzed the levels of PCBs, dioxins and several brominated flame retardants that were found in breast milk samples taken from 335 randomly selected women in Uppsala county who gave birth to children between 1996-2006.

The Swedish study found that levels of PCB declined by between 4-9% each year. For the dioxins PCDD and PCDF the levels declined by 5-7% per year. Results were less positive with regard to brominated flame retardants, as the study did not establish a decline in these levels.