Scientists are calling for stricter pesticide bans to lower deaths from deliberate pesticide ingestion. The request for this toxic pesticide ban follows a University of South Australia study detailing discrepancies in World Health Organization (WHO) classifications of pesticide hazards that rely on animal rather than human data, reports an article on Beyond Pesticides.

Earlier studies showed an increased risk of developing depression among people using toxic pesticides. Acute exposure to chemicals, including organophosphate and carbamate pesticides can put regular uses at increased risk of suicide than the general population.

This research highlights the significance of assessing pesticide toxicity and health effects using human data rather than animals to understand health effects resulting from pesticide exposure. Society tends to rank mental health risks second to physical health. However, pesticide poisonings account for one in five suicides globally.

The study’s scientists note, “The human data for acute toxicity of pesticides should drive hazard classifications and regulation. We believe that a global benchmark for registration of pesticides should include a less than 5% case fatality after self-poisoning, which could prevent many deaths and have a substantial effect on global suicide rate.”

The study found individuals suffering from pesticide exposure face a disproportionate risk of developing various health adversaries, including impaired neurological function leading to psychiatric disorders. Exposure to agricultural pesticides puts exposed people at six times greater risk of depressive symptoms, including chronic anxiety, irritability, restlessness, and sadness.

Pesticide exposure from farms or commercially-managed fields threatens residential (non-occupational) populations living nearby who are more likely to have high depressive symptoms.

Exposure to organochlorines and fumigants (gaseous pesticides) heighten an individual’s risk of depression by 90% and 80%, respectively. Organochlorines are a chemical of concern as it induces a myriad of health problems, including reproductive dysfunction, endocrine disruption, cancer, and fetal defects.

Though the U.S. bans the use of many organochlorines, these chemicals can still expose individuals to volatile concentrations as they are highly persistent in the environment. Fumigants are a human health concern as many fumigants are gases that can cause acute toxicity upon inhalation and ingestion. 

This study finds that WHO needs to address discrepancies in hazardous pesticide classifications to ensure pesticides are not a means of purposeful death.

The study is not the first to support a call to enact toxic pesticide bans. A WHO-funded study detailing such a ban can reduce annual suicides in developing countries by 28,000 people. Furthermore, it is less costly to rid of pesticides than to treat pesticide-mediated mental health disorders.