The largest study to date that quantifies and compares medical and illegal use of fentanyl in the United States suggests that illicit use is more than twice as common as medically based use. The analysis also shows the risk of a nonfatal overdose is up to three-fold higher in illicit users compared to patients exposed to fentanyl in a medical setting or through a prescription. Overall, the study found that illicit-source fentanyl exposure is linked to a significantly higher risk of opioid-related harmful outcomes than medical-source exposure.

Prenatal exposure to certain insecticides used in agriculture does not appear to be linked to social communication problems and other traits related to autism, a new study shows.