China has demanded that Canada suspend all meat exports after Chinese officials said they found traces of an additive banned in their country in a batch of pork products.

China鈥檚 decision is a bombshell for the Canadian meat industry, which exports hundreds of millions of dollars of meat products to Chinese consumers every year.

Here鈥檚 what you need to know about the banned substance, ractopamine.

WHAT IS RACTOPAMINE?

Ractopamine is a food additive that some farmers add to pigs鈥 feed about one month before they are slaughtered. The additive helps pigs put on more muscle, and is considered a cost-saving measure for farmers. It also means that the meat has a higher protein-to-fat ratio.

In Canada, the drug is sometimes given to pigs, turkeys and cattle.

IS IT SAFE FOR CONSUMPTION?

Health Canada says there is no evidence that the drug is unsafe for consumers. The U.S. has adopted the same stance. But China disagrees, and believes ractopamine and other drugs in the beta-agonist family are unsafe. Some reports suggest that the drug can have an effect on the cardiovascular system.

HAS ANYONE ELSE BANNED IT?

Yes. Ractopamine is not permitted in the European Union, Taiwan and Russia. the drug citing 鈥渨eaknesses鈥 in data.

IS IT COMMON IN CANADIAN PORK?

Not really, according to Food lawyer Glenford Jameson. He says Canadian farmers have limited their use of the growth-promoting drug due to the international bans.

鈥淚n Canada, the industry really led us to a point where most pork that鈥檚 produced in Canada doesn鈥檛 contain ractopamine, and that鈥檚 to access foreign markets,鈥 Jameson told CTV News Channel on Tuesday.

Glenford says the drug is more commonly used in the U.S., where it鈥檚 used in about 50 per cent of pork products.

HOW DOES THIS BAN AFFECT CANADA?

The ban could pose a major problem for Canadian farmers. China is the valued at $310 million, and third-largest export market for beef and veal, at around $63 million.

鈥淭his represents a very real economic threat to the stability of our food value chain,鈥 Jameson said.

IS THIS SPAT REALLY ABOUT A DRUG?

China鈥檚 abrupt announcement comes six months after the arrest of Huawei executive Meng Wanzhou in Vancouver 鈥 a move that infuriated Chinese officials. China later detained former diplomat Michael Kovrig and entrepreneur Michael Spavor in a move widely seen as a pressure tactic to release Meng. 

In March, China stopped importing Canadian canola seeds, citing the discovery of pests in two shipments. Earlier this month, Prime Minister Justin Trudeau accused China of 鈥渋nventing excuses鈥 to block Canada鈥檚 canola. Chinese officials have publicly maintained that the actions the country has taken against Canadian canola and meat are not connected to Meng鈥檚 arrest in any way. 

Agriculture Minister Marie-Claude Bibeau said Tuesday that the federal government stands 鈥渟houlder to shoulder鈥 with Canadian meat producers and defended the quality of the meat industry.