Buying organic food grown locally may sometimes be more damaging to the environment than nipping down to the supermarket for produce that has been driven hundreds of miles across the country, a new study suggests.

Research looking at the environmental impact of food from farm to the plate and beyond suggests that locally-grown food may not be as environmentally friendly as it’s said to be.

Similarly, long-distance transportation may not deserve the demonisation it has received for the emissions of carbon dioxide it generates. However, scientists questioned the growing use of aircraft to carry foods around the world.

The findings, from a study commissioned by the Department for Environment, Food and Rural Affairs to guide policy on which types of food production and consumption to encourage, prompted a furious response from the Soil Association, which promotes and certifies organic food.

The report concludes that so little is known about the overall environmental impact of any food produce that it is impossible to say which are the most environmentally friendly.

But while the merits of some organic products were recognised by the study, researchers pointed out that others cause more damage than non-organic items.

Academics from the Manchester Business School, at the University of Manchester, carried out an assessment of 150 of the best-selling foods for the survey, dubbed the Shopping Trolley Report. “There is no clear-cut answer as to whether purchasing an organic or a conventional trolley of goods has more or less impact environmentally,” they said.

“For many foods the environmental impacts of organic agriculture are lower than for conventionally-grown food.

“However, the evidence suggests that for some environmental themes organic agriculture has higher impacts than non-organic.”

They said that calculations of every aspect of a food product’s environmental impact — a life-cycle analysis — needs to be carried out to decide which forms of production are best.

Factors would include uses of land, water, fertiliser, transportation, packaging and refrigeration. The impact of organic milk was singled out for doubts about its environmental-friendliness because, while having higher levels of nutrients and needing less fertiliser, its production generates more carbon dioxide emissions. Additionally, it takes up 80 per cent more land.

Neither, said the researchers, was buying locally produced food a guarantee of being environmentally-friendly when considering the transportation system, particularly bulk haulage. They suggested that the best thing consumers could do to reduce the carbon footprint of food production and consumption was to leave their cars at home and walk or get public transport to the supermarket.

“The available data suggests that, looking at UK food transportation as a whole, the environmental impacts of car-based shopping are greater than those of transport within the distribution system itself,” the report said.

“The environmental impact of aviation are important for air-freighted products but such products are a very small proportion of food consumed.”

Professor Ken Green, who led the study, said: “If you are concerned about the carbon footprint of foods, there can be a good case for importing some of them even if they can be grown in the UK. The evidence available so far shows that local is not always the best option for the environment.”

The Soil Association criticised the authors for ignoring many of the benefits of organic production, such as improving biodiversity, and accused them of relying on an inapproporaite study which looked at a type of organic farming that is not used in Britain. It said: “Organic farming is much better for the environment than industrial methods.”

Buying organic food grown locally may sometimes be more damaging to the environment than nipping down to the supermarket for produce that has been driven hundreds of miles across the country, a new study suggests.

Research looking at the environmental impact of food from farm to the plate and beyond suggests that locally grown food may not be as environmentally friendly as it is said to be.

Similarly, long-distance transportation may not deserve the demonisation it has received for the emissions of carbon dioxide it generates. However, scientists questioned the growing use of aircraft to carry foods around the world.

The findings, from a study commissioned by the Department for Environment, Food and Rural Affairs to guide policy on which types of food production and consumption to encourage, prompted a furious response from the Soil Association, which promotes and certifies organic food.

The report concludes that so little is known about the overall environmental impact of any food produce that it is impossible to say which are the most environmentally friendly.

Although the merits of some organic products were recognised by the study, researchers pointed out that others caused more damage than nonorganic items.

Academics from the Manchester Business School, at the University of Manchester, carried out an assessment of 150 of the bestselling foods for the survey, called the Shopping Trolley Report. “There is no clear-cut answer as to whether purchasing an organic or a conventional trolley of goods has more or less impact environmentally,” they said.

“For many foods the environmental impacts of organic agriculture are lower than for conventionally grown food. However, the evidence suggests that for some environmental themes organic agriculture has higher impacts than nonorganic.”

They said that calculations of every aspect of a food product’s environmental impact — a life-cycle analysis — needed to be carried out to decide which forms of production were best.

Factors would include uses of land, water, fertiliser, transportation, packaging and refrigeration. The impact of organic milk was singled out for doubts about its environmental friendliness because, while having higher levels of nutrients and needing less fertiliser, its production generates more carbon dioxide emissions. Additionally, it takes up 80 per cent more land.

Neither, the researchers said, was buying locally produced food a guarantee of being environmentally friendly when considering the transportation system, particularly bulk haulage. They suggested that the best thing consumers could do to reduce the carbon footprint of food production and consumption was to leave their cars at home and walk or get public transport to the supermarket.

“The available data suggests that, looking at UK food transportation as a whole, the environmental impacts of car-based shopping are greater than those of transport within the distribution system itself,” the report said.

“The environmental impact of aviation are important for air-freighted products but such products are a very small proportion of food consumed.”

Professor Ken Green, who led the study, said: “If you are concerned about the carbon footprint of foods, there can be a good case for importing some of them even if they can be grown in the UK. The evidence available so far shows that local is not always the best option for the environment. The Soil Association criticised the authors for ignoring many of the benefits of organic production, such as improving biodiversity, and accused them of relying on an inappropriate study that looked at a type of organic farming that is not used in Britain. It said: “Organic farming is much better for the environment than industrial methods.”

Carbon costs

— CO2 emissions in chicken production (per kg) 4,570g nonorganic; 6,680g organic; 5,480g free-range, nonorganic

— Energy (megajoules) used in chicken production (per kg) 12mJ nonorganic; 16mJ organic; 15mJ free-range, nonorganic

— Energy used producing lamb and mutton(per kg) 23mJ nonorganic; 18mJ organic

Source: Shopping Trolley Report

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