(PAPs): Chemical Risk Assessment of Essential and Non-Essential Elements

Essential elements play a fundamental role in various metabolic, enzymatic and biochemical reactions that are part of animals’ physiological functions. According to European Regulations, conditions of use and maximum concentrations permitted were established for cobalt (Co), iron (Fe), copper (Cu), zinc (Zn), nickel (Ni),chromium (Cr) and manganese (Mn) as feed additives.

PAPs represent a potential alternative to common protein supplements, such as soy, and could be included as part of a strategic approach for establishing a circular economy.  In fact, the European Union’s Circular Economy Action Plan promotes the development of a model that emphasizes a more conscious use of non-renewable resources.

The study was conducted on 55 PAPs. Samples were collected between 2018 and 2019 according to guidelines included within the framework of official controls carried out by official authorities (CA). These samples were then stored at room temperature (25 ºC) and kept in the dark until used. The analyzed PAPs came from different plants within the EU (Italy, France, Spain and the United Kingdom) in accordance with current European regulations and were treated with different rendering processes.

The evaluation of the essential elements in PAP has shown high levels of Fe and Zn. Both of these elements are known to be naturally present in foods from plant, animal and environmental origins in high concentrations. It has been shown that an adequate supply of these elements could prevent iron deficiency anemia, as well as growth and immune system problems caused by zinc deficiency.      In addition, a high level of Zn requires a comparable concentration of Cu within feed in order to achieve the best synergistic action from these metals. Thanks to its fundamental role in protein synthesis and as a mediator of growth hormone, zinc is included as a supplement in bird diets because it positively influences bone formation and osteoblast production. Manganese (Mn) is an abundant element in the earth’s crust and plays an important role in bone mineralization, regulation of energy metabolism and protein metabolism.

  In 2016 EFSA (FEEDAP Panel) determined that manganese compounds can be considered safe for all animal species and their intake does not pose any toxicological risks. Chromium is an essential element when it is found in its trivalent form (Cr3+). It plays a fundamental role in carbohydrate metabolism, lipids, protein synthesis and growth enhancement. Instead,  when found in its hexavalent form (Cr6+) it is commonly used for pigment production or for stainless steel manufacturing and when in this form it is carcinogenic. Nickel was found in low concentrations within the investigated matrices and its toxicity depends on the exposure route.    

European Regulation represents an effective tool to measure and control different types of pollutants and elements of the environment. Their presence could often be attributed to human activity (agriculture, industry), as well as food processing or contamination.

   Preliminary data on essential and non-essential elements in PAPs from different origins establish a starting point for further investigation to be undertaken regarding these complex matrices and their chemical hazards. Considering the fact that they have been poorly investigated so far.

Thanks to their high protein content, PAPs represent an example of by-product recycling for the production of raw materials with added value. In addition, this study showed that these matrices do not seem to accumulate significant doses of inorganic contaminants, and instead are a good source of essential trace elements which play an important role in animal growth.

SOURCE: Elsevier.Processed animal proteins (PAPs) in animal nutrition: Assessment of the chemical risk of essential and non-essential elements 2022.