Growing up, I was always instructed to eat fruits and vegetables because they are healthy. I was also told by my parents to carefully wash those fruits and vegetables. Eating healthy is not so simple because of all of the chemicals that are sprayed on the foods that we eat. These chemicals are pesticides, which are used to destroy insects that are harmful to plants. Traces of pesticides are also found in household products, in the air we breathe and even in health care facilities. It has been estimated that only one percent of the four million tons of pesticides used annually actually reaches the target pests. Three million severe poisoning cases and 220,000 deaths are attributed annually to pesticide poisoning. The presence of pesticides can have a wide range of repercussions and detrimental effects on the human genome.
Pesticides are so dangerous because they commonly contain organophosphates, which are highly soluble in lipids. Because of this, they are easily absorbed into the skin and accumulate in adipose tissue, remaining in our bodies for a long time. The presence of organophosphates inhibits acetylcholinesterase, the enzyme involved in the transmission of nerve impulses. Thus the presence of pesticides can prevent proper neural transmission.
The Environmental Protection Agency has found that almost all the pesticides utilized in the United States are not directly genotoxic. However, environmental exposure to several classes of pesticides is associated with a variety of symptoms, including, skin and eye irritation, mental disorders, neurodegenerative diseases such as Parkinson’s disease, neurodevelopmental effects, reproductive dysfunctions such as birth defects or infertility and certain cancers. It has been suggested that pesticides act on the human body through epigenetic mechanisms, meaning they can be non-genetic influences on gene expression.
Agricultural workers are most at risk to the effects of pesticides because they are exposed to these chemicals on a daily basis. A study of Mexican soybean workers found DNA damage caused by pesticide exposure. Researchers found that the organophosphates, pyrethroids, organochlorines and carbamates found in pesticides are genotoxic. They react with the cell membrane and initiate lipid peroxidation, the break-down of lipids crucial to membrane integrity. They also interfere with cell regulation and induce oxidative stress, which can cause oxidative DNA damage, trigger the stimulation of cell growth, inhibit DNA repair systems and deregulate cell proliferation.
Pesticide exposure is also a known factor in the development of neurodegenerative diseases, most of which are multifactorial and caused by an interaction between environmental factors and genetic predisposition. An experiment with adult rats found that low-level exposure to organophosphates triggered the neuronal apoptosis and axonal transport deficits associated with the development of ALS and Alzheimer’s. Furthermore, a study of the brains of Parkinson’s patients found significant levels of a particular pesticide called Dieldrin which is banned in developed countries.
There is a clear correlation between pesticide exposure and genetic damage. This damage can manifest as minor health issues such as skin irritation, or major ones, such as cancer, neurodegenerative diseases and diabetes. Although the EPA has banned many of these toxic chemicals, traces remain in the soil and the air we breathe. Studies suggest that vitamin C has a protective effect against pesticides, encouraging their degradation. So make sure to eat your fruits and vegetables, but wash them well first.