Air pollution is one of the biggest threats to human life, not only in big cities but even in rural areas. We all know that air pollution causes numerous diseases from asthma to chronic obstructive pulmonary disease (COPD), lung cancer and even hearth attacks. However, a disturbing new study showed that breathing in polluted air may send soot far beyond a pregnant woman's lungs, all the way to the womb surrounding her developing baby.

The study, conducted in Belgium, examined samples of placenta from a pregnant woman and discovered black carbon embedded within the placenta cells. The amount of black carbon in the placenta correlated with the woman's air pollution exposure, which was estimated based on emissions of black carbon near her home.

The discovery suggested that the residue from air pollution harms babies' development and causes various diseases even when the baby is still in its mother's womb. These developmental problems also have been tied to an inflammatory response to air pollution in a mother's body, including inflammation within the uterus.