Objective: Describe the possible adverse effects on population health and environment due to pesticide use in agricultural zones in Colombia, and implement the best agricultural practices (BAP) in tomato production. Materials and methods: A descript intoxicative study was carried out in the municipality of Merced-Caldas, consisting in three phases: a diagnostic phase, in which environmental and biological samples were collected, using a sample of 132 agricultural workers. In a second phase, BAP were implemented, and in the third phase, the results were evaluated. A univariate analysis was completed and posible associations were explored. Results: Average length of exposure to pesticides was 9 years. The central nervous system was the most affected (95.5%), followed by sensory organs (46.2%), the digestive system (33.3%), skin (21.2%) and others (19.7%). Organoclorides were found in 97.0% (128), inhibition of acetylcholinesterase enzyme was found in 43.1% (45); no metabolite ethylenethiourea was found. In the environmental samples, presence of organophosphates was found in tomatoes and soil. In water and mud samples, organochlorides were found. There was a statistically significant difference between BPA farms and traditional farms. (p=0,020). Conclusions: Risks due to pesticide use were demonstrated, and the need to strengthen vigilance on the potential effects of pesticide use.