Retailers, in particular, are taking a far too simplistic view. 'Greenness' is very marketable, and a convenient way to promote the supermarkets' 'environmental conscience'. However, the majority of leading multiples are missing the point.

Reducing greenhouse gas emissions is a priority, but focusing on fuel and carbon foot prints is not necessarily the best way to do it.

"Transport and CO² emissions are too simple a theory because these areas cannot be viewed in isolation," says Randi Dalgaard, research graduate at Aarhus University, Denmark. She has been studying Life Cycle Assessments (LCAs) for food products since 2001.

"Producing food and getting it to consumers involves far more than just transportation. How the food is produced and the sustainability of the processes used is the real issue and it's these areas which need to be addressed," she explains.

Randi Dalgaard - food miles involves far more than just transportation

Her studies show that 44 per cent of the emissions created by Danish pig production are from Nitrous oxide. CO² accounts for 36 per cent, Methane 19 per cent with the rest are other marginal gases (1%).

"If you only consider Carbon dioxide emissions then you do get the wrong picture. Other elements are equally significant and have a greater impact on the environment. Nitrous oxide is a significant greenhouse gas and it is three times more damaging than CO²," explains Ms Dalgaard.

Her investigations show that the fuel burned as food miles is marginal compared with the energy used elsewhere in the production chain. Her findings are also supported by studies at the Cranfield Institute in the UK.

For Danish pork, transportation only contributes around 1.5 per cent to the overall greenhouse gas emissions produced by the entire production chain (farm to plate). So, environmentally conscious buying decisions should really reflect the wider picture, says Ms Dalgaard.

"Just because a food has been produced locally or in the same country does not mean it is more environmentally friendly. You need to evaluate the whole production system; how much energy is used here; how much nitrate and phosphorus are produced. Imported food products may be more efficiently produced in terms of their environmental impact, because the systems used are more environmentally efficient," she explains.

Key information

Her department has recently completed investigations for the Danish Meat Association (DMA) to assess the environmental impact and resource use of Danish pigmeat production - key information for an industry founded on exports.

The studies show that transporting pork, whether within national borders or by hundreds of miles across the globe, is not as damaging to the environment as the methods used to actually rear the pigs. Denmark's pig industry is striving to reduce its environmental foot print. However, the systems used on many Danish units can inflict more environmental damage than the transport logistics used to export the pork produced.

As with most intensive livestock systems, most of the greenhouse gases attributed to pig production are produced from growing the grain and soya used as feed. Manure is also a significant contributor, followed by the energy used in the rearing accommodation and at the slaughterhouse. In total, the equivalent of 3.5kg of CO² is released to the environment for every kg of Danish pork produced - around the same as a nine-kilometre car journey. But more than 2kg of this CO² relates to the feed.

Efficiency equals better environmental control

Production models suggest that increasing efficiency at farm level would have a significant impact on reducing greenhouse gases. The economics also stack up because more efficient systems require fewer inputs. The Danish pig sector is driving for increased productivity and greater feed conversion. Producers here are already on target to raise the number of pigs weaned per sow per year from 26 to at least 28 by 2015. They also want to cut overall feed use by more than 10 per cent.

This will go some way to improve sustainability, but for Denmark's industry the main environmental hotspot is manure handling and disposal.

Danish farmers are subject to tight restrictions on slurry spreading. Regulations are a-kin to the UK's IPPC rules and water protection laws. However, new legislation now dictates that farmers with more than 120 animal units (four sows and piglets) must own at least 30 per cent of the land required to spread their manure. Nutrient leeching and acidification are key concerns in Scandinavia, but the use of reduced protein feeds and better manure handling is helping livestock farmers to control the problem.

The environmental profile of Danish pork has improved during the past 13 years and further improvements can be expected if they achieve their efficiency targets.

A significant reduction in the amount of greenhouse gas emissions produced by livestock industries across the world can only be achieved if environmental hotspots are identified throughout the production chain and addressed.

The logistics needed to transport inputs to the farm, and then move end products to market, do have an environmental impact, but proportionally they are small compared to the detrimental effects that some resources, production techniques and husbandry factors can generate.

To comply with legislation producers will need to alter their production methods, But retailers and the public also have a responsibility. They too must understand the real dynamics of sustainability and support it. Only then can agriculture make a significant difference in cutting down greenhouse gas emissions and reduce its impact on the global environment.

For details on the Life Cycle Assessment methodology go to: www.LCAfood.dk

Read more about Danish pig production here

July 2007