Proportion of children aged 2 to 5 years displaying signs of hyperactivity – inattention, Canada, 2000 to 2006

Source: CICH graphic created using Government of Canada. The Well-Being of Canada’s Young Children. Government of Canada Report 2011. – accessed May 22, 2017.

In 2006, 6.2% of children from 2 to 5 years of age displayed signs of hyperactivity – inattention. This was 6.0% in 2000, 5.5% in 2002 and 6.6% in 2004.


Neurodevelopmental disorders among young children have been associated with exposure to environmental toxins.1,2

These are disorders that affect the neurological system and brain – for example attention-deficit/hyperactivity disorder (ADHD), autism, learning disabilities, intellectual disability, conduct disorders, cerebral palsy, and impairments in vision and hearing.

Lead, methylmercury, and polychlorinated biphenyls (PCBs) have been associated with negative effects on the developing brain and nervous system of the fetus and young children. This association has been shown in multiple studies. Exposure is widespread in Canada.1,2

Other environmental toxins have been identified as having potential concerns for the developing nervous system and brain – these have not been as widely studied, but young children are exposed to them in Canada.  They include the organophosphate pesticides, polybrominated diphenyl ether flame retardants (PBDEs),1 phthalates, bisphenol A (BPA), polycyclic aromatic hydrocarbons (PAHs), arsenic, and perchlorate.2

1Abelsohn AR and Sanborn M. Lead and children: Clinical management for family physicians. Canadian Family Physician June 2010 vol. 56 no. 6 531-535.
2Environmental Protection Agency. Children’s Health and the Environment Third Edition. 2013. -accessed July 24, 2017.