MARBLES is focused on the environmental triggers that children are exposed to prenatally and post-partum. Information about each participant's environment is collected through a number of sources in order to obtain a comprehensive picture of the environment surrounding each pregnancy.

Information is gathered through the collection of blood, urine, and breast milk (if the mother is breast feeding). In addition, dust samples are collected from the participant's home in order to test for materials in the air that may be associated with the development of autism.

Finally, information is also obtained through interviews conducted with the mother, using standardized questionnnaires, and accessing medical records in order to uncover more information about any behavioral aspects or trends that may contribute to the development of autism.

• Exposures: viral or other illnesses, pesticides and environmental contaminants toxic to the immune and nervous systems, medications

• Lifestyle factors

• Immune system function

• Metabolism

• Behavioral markers