Introduction: some toxic-environmental factors are frequently related to malignant hematological diseases, which have increased in recent years. Objective: to describe the frequency of appearance of toxic-environmental factors in patients diagnosed with hematological neoplasms. Method: a study was conducted cross-sectional descriptive study in patients diagnosed with hematological pathologies in the year 2020, a structured interview was applied to them looking for toxic-environmental factors, occupation, contact with toxic substances, origin, drinking water, toxic habits, diet, among others. Patients who used pesticides were given a second interview that collected: the type of substance, exposure time, time since last exposure, history of poisoning, protection measures, knowledge and application of the same. Results: patients with lymphoma predominated. non-Hodgkin (25, 5 %), ages between 61-80 years (50 %), farmers (31 %), rural origin (57 %), those who had contact with toxins (64, 4 %). The most used toxin was pesticides, the average exposure time was 14 years, the last contact 9, 2 years, protection measures are used only sometimes, their need is unknown and 90% do not know any protection measure. Conclusions: according to the results it is necessary to create strategies to guide the population about this risk and how to modify it.