Introduction: Today, health of agricultural crops throughout the world is exposed to the excessive use of chemical pesticides and toxicants. Use of pesticides by farmers is associated with various factors. On this basis, the present study is aimed to investigate the farmers' practice in optimal use of toxicants and pesticides in city of Sari based on a behavioral theory. Methods: The present cross-sectional study was conducted on 300 farmers living in Sari region, who were selected via random sampling method, in 2017. The data collection tool was composed of three parts. Accordingly, the first part included demographic information and agricultural characteristics, the second was focused on farmers' knowledge and practice of using chemical pesticides, and finally the last part embraced the TPB constructs (including attitude, subjective norms, perceived behavioral control, and behavioral intention). Once data collection was completed, they were analyzed using statistical methods. Results: The mean score of knowledge and practice was lower than 50% of the total achievable score, while the mean score of the TPB constructs was higher than 50% of the total achievable score. The regression results indicated that the subjective norms and perceived behavioral control were significant predictors of the framers' behavioral intention for controlling the overuse of pesticides (P<0.001). Furthermore, the multivariate linear regression showed that TPB constructs and the "knowledge"explained 31% of the variance of the framers' behavioral intention. Conclusion: Observing the obvious importance of some of the constructs) over other constructs can serve as a guideline for policy-makers in terms of planning for the projects which aim to reduce agricultural toxicants use.
