Owen Jennings: Driving a stake through the steak

You are in your favourite restaurant. You have narrowed down the choices to two fillet steaks. They are both grassfed from New Zealand.

One is proudly claimed to be from a farm that uses management techniques to help lower methane emissions. That has to be a plus, surely. The other steak makes no such claim. You are almost ready to order when you meekly check – “what are these ‘management techniques’ that lower methane emissions?”

After all, you know full well that New Zealand has the lowest carbon footprint of any food producing country in the world. You are also know that all Kiwi farmers are contributing a miniscule four millionths of a degree of warming per year according to the country’s leading climate scientist. You are even smart enough to know from your primary school science that farmers use CO2 to grow grass. They have some hotly debated methods for measuring methane emissions with a growing number claiming New Zealand numbers are massively exaggerated.

So, you are pretty comfortable eating a steak from a New Zealand farm. So, what’s the deal with these ‘management techniques’ that are claimed to reduce methane emissions?

Being a discerning gastronome you only eat where the chefs know their stuff. They are able to describe in some detail what the ‘management techniques’ are that your menu boasts.

“It means the farmer involved has been forced to use a tribromomethane (bromoform) product on his beef animals by the company who process his stock. Bromoform is found in some seaweeds, algae and plankton.

It is harmful if swallowed, inhaled, or absorbed through the skin, and may damage the liver, kidneys, and nervous system. Long-term exposure is linked to cancer risk in animal studies. It’s now mostly a lab chemical or a research interest, not a common consumer product.

Some experimental cattle feeds (e.g., Asparagopsis taxiformis seaweed) are being studied to reduce methane emissions from ruminants. These feeds contain high natural levels of bromoform, which can end up in meat and milk in small quantities. The product is banned from use in dairy stock.

Bromoform is ozone-depleting, classified as a volatile organic compound (VOC), and in some jurisdictions like the USA, is banned from use in all livestock destined for human consumption. Even in New Zealand, these products are restricted from use in breeding or dairy cattle.

By now you are sitting up and listening even more querulously. “How does this toxic substance end up in a farm animal”, you ask, a little stunned.

Farmers round their animals up every few months and with great difficulty and danger to themselves and their workers, force a large bolus down their throats and very minor amounts of bromoform are gradually eroded from that bolus to restrict the production of methane. It alters the natural processes of digestion.

High doses can harm rumen microbes or disrupt digestion as the bromoform can be absorbed into the bloodstream and leave trace residues in milk and meat if levels are too high. Chronic exposure might cause toxicity in the animal if not carefully managed.

“Excuse me waiter. I’ll have the steak that doesn’t come with the ‘management techniques’, thank you”.

Former MP.Owen Jennings, a former Member of Parliament and President of Federated Farmers, maintains a keen interest in ensuring agricultural policies are sensible and fit for purpose.