The ESPINA Cohort study has published preliminary findings on exposures to herbicides including 2,4-D, which are inconsistent with the existing weight of scientific evidence and regulatory decisions.
More than 4,000 peer-reviewed studies have been published on 2,4-D making 2,4-D one of the most studied active ingredients in the world. Health and safety regulators from many countries, including the US, have analyzed these studies and consistently found that 2,4-D meets stringent modern safety standards for human, animal and environment health. No regulatory agency in the world has concluded that 2,4-D causes adverse human health effects when used according to the label.
2,4-D has been the subject of state-of-the-art toxicology studies as well as many previous current and previous epidemiology studies. These studies and many others support that 2,4-D does not cause neurotoxic outcomes at levels humans are exposed to. The trace levels of 2,4-D that may be detected are consistently thousands of times lower than regulatory thresholds set to protect human health.
In its recent evaluation, EPA scientists found no evidence of ESPINA’s claims at levels humans are exposed to. 
Those looking for more information on 2,4-D can find it at 24d.org. Those looking for regulatory decisions supporting 2,4-D’s continued registration in the United States, Canada, and around the world may visit 24d.info. The 2,4-D Research Task Force is made up of companies holding technical registrations on the active ingredient in 2,4-D herbicides.
Secondary Exposures to Pesticides among Children and Adolescents (ESPINA) Study: Urinary Glyphosate, 2,4-D and DEET Biomarkers in Relation to Neurobehavioral Performance in Ecuadorian Adolescents in the ESPINA Cohort | Environmental Health Perspectives | Vol. 131, No. 10 (nih.gov)