The widespread use of pesticides in agriculture and gardening not only affects animals. Exposure to these toxins extends to humans, too.
Research led by scientists from Duquesne University in the United States has now discovered that exposure to low doses of the insecticide chlorpyrifos, one of the most used in agriculture in recent decades, negatively affects brain development in frogs.
The results of this study raise suspicions about the neurological risk -also in humans- associated with this type of organophosphorus products.
Chlorpyrifos is a crystalline organophosphorus insecticide commercialized worldwide since 1965 that inhibits acetylcholinesterase, causing poisoning by the collapse of the insect’s nervous system.
Chronic exposure to this substance marketed under names such as Brodan, Detmol UA, Dowco 179, Dursban, Empire, Eradex, Inaclor, Lorsban, Paqeant, Piridane and Scout, has been linked to neurological effects in humans, developmental disorders and autoimmune disorders, despite which it has been widely used in agriculture and gardening.
The widespread use of pesticides in agriculture and gardening not only affects the insects and herbs that it is intended to control but also frequently contaminates natural habitats and various organisms that are not the target of treatments.
Insecticides and herbicides can unintentionally affect various species, especially in aquatic environments, even at very low levels of concentration or indirect exposure, for example, animals that feed on contaminated plants.
The new research was carried out with tadpoles and adult specimens of leopard frog and the results published in the scientific journal show that exposure to this chemical can damage the northern leopard frog by inhibiting its brain development.
Authors indicate that the damage has been observed even in situations where the pesticide did not cause a decrease in the food source of the amphibians.
“Organophosphorus pesticides contaminate surface waters throughout the United States, exposing both animals and humans to these chemicals, often at very low levels.
This study shows that exposure to these pollutants, even at these low concentrations, affects the neurodevelopment of vertebrates,” said the study’s lead author, Professor Sara McClelland.
The leopard frog is a species of anuran amphibian of the Ranidae family. Its natural habitat extends from the south of Canada to the northeast of Mexico. It is also present in many other parts of the planet by human introduction or accidental expansion.