In recent years, some companies have launched projects to reduce CO2 in fields with a view to "sustainable agriculture". But can agriculture that, while reducing atmospheric emissions, still makes use of pesticides truly be called sustainable?

Behind perfect, gleaming apples and peppers lies the pollution of water, soil, air and the human body. Pesticides, in fact, compromise the balance of the planet just as much as the balance of the human body. Even at concentrations lower than those used.

Two recent studies, one from the University of California and the other from the Fred Hutchinson Cancer Research Center in Seattle, focus on the health risks of pesticides. The first demonstrates how they increase the risk of developing Parkinson's disease, and the second how they promote endometriosis in women, a condition that, among its consequences, also leads to infertility.

Pesticides and Parkinson's: researchers have identified a number of widely used pesticides that increase the risk of Parkinson's disease. In a previous study, the same university had already discovered that exposure to the fungicide Benomil (now banned) increased this risk; the new research identifies a further 11 pesticides that act in the same way. In practice, these substances inhibit the enzyme aldehyde dehydrogenase (ALDH), thereby interfering with dopamine production — a chemical whose deficiency causes tremors, limb stiffness and loss of balance, signs typically associated with Parkinson's. The researchers also found that people with a common variant of the ALDH2 gene are particularly vulnerable to these pesticides. People with the variant are two to six times more likely to develop the disease when exposed to pesticides than those without the variant.

According to the study, the levels at which pesticides inhibit the enzyme are far lower than those normally used in agriculture. "We were very surprised to find that so many pesticides inhibit ALDH and at such low concentrations, which are well below those needed for pesticides to do their job," commented the study's author Jeff Bronstein, professor of neurology and director of movement disorders at the University of California Los Angeles. "These pesticides are found virtually everywhere — in our kitchen cupboards as well as in parks and golf courses, in pest control inside buildings and homes. So this significantly broadens the number of people at risk," he added.

Pesticides and endometriosis: the causes of this very complex chronic disease are somewhat clearer following the results of this study. Conducted on 248 women with endometriosis, it assessed the presence of two pesticides in the blood — Mirex and Beta-hexachlorocyclohexane, banned in the United States for 20 years but still present in the soil. The analyses revealed that women with the highest concentrations of Mirex face a risk of contracting endometriosis that is 50 per cent higher, compared with an increase of between 30 and 70 per cent for those with greater quantities of Beta-hexachlorocyclohexane. It is estimated that 3 million women in Italy are affected by this condition, which causes fertility problems and pain that compromises quality of life. The tests also made it clear that, despite restrictions or bans on the use of certain pesticides, these were nonetheless detected in the blood of the women examined and were linked to the increased risk of endometriosis, demonstrating that the action of pesticides persists over the years, even when used in the past.