###### Abstract  
Fungicides are compounds with potentially toxic effects on the human body, but the molecular mechanisms of their action have not yet been explained. The effect of cyprodini on cell viability, apoptosis level, cell membrane function, cell morphology and expression of antioxidant enzyme genes in the A-375 and DLD-1 cell lines was examined. The cell lines were selected because they can be an excellent in vitro model of neoplastic changes occurring in the skin and large intestine after exposure to a fungicide. The fungicide selected for the study is commonly used in Poland to protect crops against fungi. Our results showed that the tested compound increased cell viability and proliferation, probably activated by mechanisms related to oxidative stress. Cyprodini caused an increase in glutathione level (in A-375 by about 37% and in DLD-1 by about 28%) and oxidative stress enzymes activity, but not in apoptosis level. Its membrane interactions and its penetration into cells was concentration dependent. It is worth emphasizing that the novelty of our work lies in the use of non-traditional toxicological methods based on molecular analyses using human cell lines. This allowed us to demonstrate not only the toxicity of a single substance but also its behavior within cellular structures. Our findings suggest that cyprodini may have tumor-promoting properties in skin and colorectal cancer cells. cyprodini; microcontaminant; cancer; fungicide; A-375; DLD-1  
17 June 202  
fungicides have on the human body. Considering the very frequent use of plant protection products in agriculture, residues of these compounds can be detected in many species of plants obtained from various types of crops. In addition, accumulation of pesticides and their derivatives in soils has been found, which causes the spread of these substances into the area that was not previously contaminated. People who come into contact with products containing even trace amounts of pesticides may be exposed to health complications [2]. The most vulnerable are people involved in agriculture, who have physical contact with, for example, plant protection products. They can penetrate the body through three routes: the digestive system, the respiratory system and the skin [3]. Cyprodini is a compound belonging to the anilinopyrimidine group, used as a plant protection agent with a broad spectrum of fungicidal action. The action of the fungicide is based on the inhibition of methionine synthesis in fungal cells, which results in inhibition of the growth and development of the pathogen [4]. Cyprodini was used for the cultivation of cereals (wheat, barley, rye), fruit plants (apple trees, pear trees, plum trees, sour cherries, sweet cherries, grapevines), vegetables (tomatoes, potatoes) and ornamental plants. Studies conducted on rats with oral administration of cyprodini have shown that to a small extent, this substance remained in animal tissues for a short period of time. No aggregation of the substance was confirmed. Dermal contact with cyprodini resulted in the presence of residues of the substance in blood, skin, urine and feces and within 48 h, 3-20% of the cyprodini dose was absorbed (depending on the concentration used) [5]. Pesticides affect DNA methylation, which leads to changes in gene expression and carcinogenesis. These compounds adversely affect the modification of histones. They are involved in the formation of chromatin, considered to be a messenger of epigenetic memory and the expression profile of miRNAs. miRNAs are responsible for regulating gene expression. These changes affect the incidence and progression of human cancers [6]. Different classes of pesticides are associated with different types of human cancers [7]. Lung cancer was the most frequently observed among pesticide applicators, as well as skin cancer, followed by prostate cancer, multiple myeloma and colon cancer. An increased risk of cancer was found among pesticide applicators.