body burden of PBDEs in Americans correlates well with the level of PBDEs measured in swabs of their hands, likely picked up from dust.[55][56] Dust exposure may occur in the home, car, or workplace. Levels of PBDEs can be as much as 20 times higher in vehicle dust as in household dust, and heating of the vehicle interior on hot summer days can break down flame retardants into more toxic degradation products.[57] However, blood serum levels of PBDEs appear to correlate most highly with levels found in dust in the home.[56] 60-80% of exposures are due to dust inhalation or ingestion.[50][51]. In addition to this, 20% to 40% of adult U.S. exposure to PBDEs is through food intake as PBDEs bioaccumulate in the food chain. High concentration can be found in meat, dairy and fish with the remaining exposure largely due to dust inhalation or ingestion[50][51]. Individuals can also be exposed through electronic and electrical devices. Young children in the United States tend to carry higher levels of flame retardants per unit body weight than do adults.[59][60] Infants and toddlers are particularly exposed to halogenated flame retardants found in breast milk and dust. Because many halogenated flame retardants are fat-soluble, they accumulate in fatty areas such as breast tissue and are mobilized into breast milk, delivering high levels of flame retardants to breast-feeding infants.[51] PBDEs also cross the placenta, meaning infants are exposed in utero. Mothers thyroid hormone (T4) level can be disrupted and exposure in utero in rat studies has been demonstrated to alter motor control, delay sensory development and puberty. Another reason for high levels of exposure in young children are due to aging consumer products age, small particles of material become dust particles in the air and land on surfaces around the home, including the floor. Young children crawling and playing on the floor frequently bring their hands to their mouths, ingesting about twice as much house dust as adults per day in the United States.[58] Children also have a higher food intake per kilogram of bodyweight compared to adults. Young children are also exposed to flame retardants through their clothing, car seats and toys. The introduction of these chemicals came about after the tragic death of children wearing brushed rayon fabric that would ignite easily. The U.S enacted the Flammable Fabrics Act passed in 1953 after which, flame retardants were mandated to be added to many