A field survey study  was conducted during the two successive winter seasons of 2016/2017 and 2017/2018 near the Factory ofNitrogen Fertilizers and Chemical Industries near Mansoura city, Dakahlia Governorate to investigate the effect of the factory wastes on nitrate and nitrite contents in  the edible parts of some vegetables, soil and water. The experimental design was randomized complete block design (RCBD) with three replications. Samples of three vegetable crops; i.e.; potato, sweet pepper and watercress, soil and water were taken from both sides of the main drainage channel  of wastes in three distances at (1, 3 and 5 km) from the factory, besides control treatment at the opposite direction from the factory.
The study revealed was significant differences in (NO₃^-) and (NO₂^-) contents in the edible parts of vegetables, soil and water as follows:

The highest values of (NO₃^-) in potato tubers contents were (16.65 and 15.72 ppm) and (NO₂^-) were (0.477 and 0.500 ppm) at the highest distance (5 km) from the factory during the both seasons of study, respectively . In fruits of sweet paper, the highest contents of (NO₃^-) were (39.19 and 36.45 ppm) and (NO₂^-) were (1.223 and 1.457 ppm) at the longest distance  (5 km)  during the both seasons. The highest contents in leaves of watercress of (NO₃^-) were(77.46 and 81.32 ppm) and (NO₂^-) were (4.95 and 5.56 ppm) during the both seasons of study at the highest distance(5 km), respectively.

At the farthest distance from the factory (5 km), the highest contents in soil of (NO₃^-) were(12.62 and 12.75 ppm) and (NO₂^-) were (1.120 and 1.180 ppm) respectively, during the both seasons. 
The highest contents of (NO₃^-) in water were (65.88 and 65.75 ppm) and (NO₂^-) were (2.687 and 2.727 ppm) at the intermediate distance    (3 km) from the factory during the both seasons of study, respectively.While, the lowest contents of (NO₃^- and NO₂^-) in the edible parts (potato tubers, fruits of sweet paper, leaves of waterc  ress), soil and water were obtained from the control treatment (the opposite direction of the pollution source) in both seasons.