Evaluation of the environmental impact of heavy metals concentration from industrial by-products that could be used as feed additives in poultry diets

The food industry by-products come in large amounts worldwide, reaching up to 50% of the total waste produced in some countries. This is both an economic, social and environmental problem. On the other hand, the compound feeds are the main cost factor for farmers, reaching up to 80% of the production cost for poultry. Any proper use of low input feeds improves the poultry production performance, but it remains to evaluate the environmental impact of these by-products. The paper presents the environmental and animal health impact of 22 vegetal by-products in terms of their heavy metals load. The environmental impact of these industrial by-products was considered in the circumstance of their storage on the soil. There were determined the concentration of cadmium, cobalt, total chromium, copper, nickel, lead and zinc. The evaluation of potential risky by-products for animal health was done by comparison of the analytical results with the regulations regarding the quality and salubrity for feeds and feed additives. The results show that seven by-products samples exceed the upper admitted levels of heavy metals concentration. In the poppy meal exceeded Cd concentration (1.88 mg Cd / kg vs legally allowed value of 1.0 mg/ kg) and Cu concentration (60.0 mg Cu / kg vs legally allowed value of 35.0 mg / kg). Also, the sesame meal exceeded the Cu concentration (59.7 mg Cu / kg vs legally allowed value of 35.0 mg/ kg). In the germ meal wheat exceeded the Zn concentration (273 mg Zn / kg vs legally allowed value of 250 mg/ kg). In other 4 samples (poppy meal, sesame meal, sunflower meals, nuts meal) exceeded the Cu concentration. The following analyzed by-products showed to be safe for animal health and for the environment: soybean meal, meal of mustard, buckthorn meal, flax meal, apple mash, full fat mixed sites, marc and leftover vegetables.