Risk Assessment of Copper and Molybdenum and Other Minerals in Feed Ingredients and Finished Feeds

This is a risk assessment for six mineral contaminants and four essential minerals. A total of 1,466 samples were collected from 18 product categories during 2010 to 2018. The 18 product categories were divided into 11 finished feed (689 samples) categories and seven feed ingredient categories (777 samples). Mineral and vitamin/minerals mixes (565 samples) were the predominant products in the seven feed ingredient categories, and beef cattle feed (351 samples) was the predominant product in the 11 finished feed categories. Samples from the 18 product categories were analyzed for up to 10 minerals: arsenic (As), cadmium (Cd), chromium (Cr), copper (Cu), lead (Pb), molybdenum (Mo), mercury (Hg), nickel (Ni), selenium (Se), and thallium (Tl). Cr, Cu, Mo, and Se are essential nutrients, and the other six are contaminants. The ratios of mean concentrations of the 6 inorganic contaminants across the 11 finished feeds were low compared to the seven feed ingedients categories. This implies that the risk of toxicity from the potential carryover of the six contaminants from feed ingredients to finished feeds is low. The mean Cu concentrations were high and the mean Mo concentrations were low in the four finished feed categories for ruminants (cattle, sheep, and goats). The ideal copper:molybdenum (Cu:Mo) ratio is >6:1 and <10:1 in the four finished feed categories for ruminants. The calculated Cu:Mo ratio of 26:1 shows a nutritional imbalance between Cu and Mo that may cause Cu toxicosis with long-term exposure.https://doi.org/10.21423/jrs-v07pos