The truth about hormones in beef
Prof EC WebbHead: Department of Animal & Wildlife Sciences, University of Pretoria
Email: Edward.webb@up.ac.za
The truth about hormones in beef is comparable to the simplest oxygen hydride in nature which is often the cause of severe damage, disease or financial loss to humans and the environment. H2O, commonly referred to as water is also vital to virtually all forms of life. Similarly, hormones occur naturally in all biological organisms in varying quantities, including animals and animal products, plants, seeds and extracted fats and oils. Hormones also occur in products from animal origin like meat, milk and eggs. It is accepted that hormones or hormone-like substances (phyto-hormones and even endocrine disrupting compounds) are present in many other food sources and water. Vegetables, fruits, grains and oils extracted from sources like soya and sunflowers contribute a major portion of the dietary hormones ingested by humans.
Beef generally provide a relatively small concentration of six important hormones in the human diet. Three of these are produced naturally in animals notably testosterone, esatradiol-17beta and progesterone, while trenbolone acetate, zeranol and melengesterol acetate are xenobiotic compounds. Commercial forms of these hormones are registered growth enhancing compounds in South Africa, USA and many other countries in the world, excluding the European Union (EU). Most of these substances are only available as subcutaneous implants in the ear which slowly release a small and safe concentration of the hormone to the animal. Antibiotics are no longer used as growth enhancers in South Africa, while the non-steroidal repartitioning agents that are included in the feed are quite popular. It is important to note that it is not economical to overdose any hormone because there is now benefit in terms of animal growth and efficiency.
The safety of meat from treated animals is assessed based on the acceptable daily intake and maximum residue limit in tissues. The results of various studies indicate that there are extremely low concentrations of these substances in meat from hormonally treated animals. It was scientifically established that 250g steaks from steers treated with oestradiol-17beta contain about 5ng of the hormone compared to steaks from steers not implanted with the hormone that contained about 2,5ng. A more practical example is that the hormone content of one beer (340ml) is equivalent to about 10 steaks of similar weight each.
It is clear from a number of these scientific studies that there are major concerns about the EU ban on hormonal implants in livestock production as a “precautionary principle”. Unfortunately this ban adversely affected the perception of the quality of meats produced outside the EU. This prompted a number of local producers and chain-stores to market “hormone-free” meats, but the differences are negligible. These meats are obviously not free of hormones, although the hormonal content is marginally lower compared to hormonally treated animals.
The most important point though is that the hormone levels of even hormonally treated cattle is about 1% of that synthesised in pre-pubertal males or females, which relates to extremely low levels. Consequently the Codex Alimentarius Commission determined that meat from hormone-treated cattle according to good practice is perfectly safe for human consumption. The hormone content of normal eggs, milk and certain oils like soya oil are appreciably higher compared to that in beef. South African beef produced according to acceptable procedures still provides one of the best and safest sources of high quality proteins.
