Overview: Pesticides & Human Health

This briefing by the Canadian Association of Physicians for the Environment summarizes three systematic reviews regarding the adverse human health effects of pesticide exposure. It details the types of pesticides, routes of exposure, and the specific risks posed to vulnerable populations, concluding that the health hazards of toxic pesticides outweigh the benefits of cosmetic use.

• Pesticides are categorized into several families with varying levels of environmental persistence. Organochlorines are highly persistent and now banned in Canada, while organophosphates (including glyphosate, the most used herbicide in Canada and globally), pyrethroids, carbamates, and thiocarbamates have intermediate or shorter persistence. Other families include phenoxy herbicides and triazines.
• Pregnant women, fetuses, and children are identified as the most vulnerable populations due to rapid cell division in embryos and the developing nature of children's brains and organs. Children face higher exposure risks because they breathe more frequently, have a higher skin-area-to-body-weight ratio, spend more time on the ground, and frequently put objects in their mouths.
• Acute pesticide poisoning in Canada is estimated to affect approximately 6,000 people annually, with children accounting for 47% of these cases. Acute symptoms can affect the eyes, skin, nervous system, respiratory system, cardiovascular system, and gastrointestinal tract.
• Systematic reviews have linked pesticide exposure to various cancers. A 2007 review found positive relationships with brain, prostate, and kidney cancers, leukemia, and non-Hodgkin lymphoma (NHL). A 2015 review provided 'good evidence' for associations with NHL, as well as childhood lymphoma, brain cancer, Ewing’s sarcoma, neuroblastoma, and leukemia.
• Pesticide exposure is associated with adverse reproductive and neurological outcomes. Evidence includes associations with birth defects (such as cleft palate, neural tube defects, and hypospadias), altered fetal growth (specifically birth weight and head circumference), and neurological conditions including Parkinson’s disease, ALS, and Alzheimer’s disease. In children, organophosphate exposure during pregnancy is linked to increased risks of ADHD and autism spectrum disorders.
• Respiratory impacts associated with pesticides include increased asthma and wheezing, particularly in children, pregnant women, and infants. While one review found no overall association across all studies, it did identify associations with COPD, hay fever, and allergic rhinitis in specific populations.
• The document argues that the health risks of toxic pesticides outweigh the benefits of their use on lawns and gardens. It advocates for the banning of non-essential cosmetic uses and the implementation of 'white lists' of safe alternatives, citing the Government of Ontario as an example of successful reduction.

APA

Arnold, I., Perrotta, K., & Sears, M. (2017). Overview: Pesticides & Human Health. Canadian Association of Physicians for the Environment. https://cape.ca/wp-content/uploads/2018/03/1.CAPE-Pesticides-Health-Backgrounder-Sept-22-2017.pdf

Chicago

Arnold, Ian, Kim Perrotta, and Meg Sears. Overview: Pesticides & Human Health. Canadian Association of Physicians for the Environment, 2017. https://cape.ca/wp-content/uploads/2018/03/1.CAPE-Pesticides-Health-Backgrounder-Sept-22-2017.pdf.

Wikipedia

{{cite report |last1=Arnold |first1=Ian |last2=Perrotta |first2=Kim |last3=Sears |first3=Meg |title=Overview: Pesticides & Human Health |publisher=Canadian Association of Physicians for the Environment |date=August 2017 |url=https://cape.ca/wp-content/uploads/2018/03/1.CAPE-Pesticides-Health-Backgrounder-Sept-22-2017.pdf |access-date=17 August 2026 |via=Climate Insights Directory}}

BibTeX

@techreport{arnold2017overview, author = {Arnold, Ian and Perrotta, Kim and Sears, Meg}, title = {{Overview: Pesticides \& Human Health}}, institution = {Canadian Association of Physicians for the Environment}, year = {2017}, month = aug, url = {https://cape.ca/wp-content/uploads/2018/03/1.CAPE-Pesticides-Health-Backgrounder-Sept-22-2017.pdf}, urldate = {2026-08-17}, note = {Indexed by Climate Insights Directory} }