The ß-agonist clenbuterol and comparable substances such as cimaterol and salbutamol cause a shift from the production of fat to the production of muscle tissue in calves and other animals. The substances are not without danger for humans.
Clenbuterol
Hair sample testing
In addition to urine and livers, feeds and drinking water were regularly checked, in a more directed way, for the presence of ß-agonists. In the future even hair may be monitored. Hair has one big advantage: diverse substances such as clenbuterol remain present there for a very long time (up to 70 days after administration) and it is very easy to take hair samples. However the analysis of hair is relatively laborious and expensive thus far.
Beef farms
In addition to governmental inspections, the Cattle Quality Inspection also checks beef farms for the use of forbidden growth promoters such as hormones and ß-agonists. In 1997 the Cattle Quality Inspection service performed about 20,000 checks on beef farms, and found irregularities at only three farms.