Greenhouse Gas Ban Could Push Up Food Prices

Food quality will fall, food costs will rise and stored food will be damaged. Historical relics may be lost to insect attack, rodent and insect infestations on public transport will swell, and fungal contamination of stored food will increase. According to a recent meeting of the Society of Chemical Industry (SCI) Pest Management Group, these may be the consequences of a worldwide phasing out of the crop protectant methyl bromide (MB).

The SCI Pest Management Group invited acclaimed speakers from across the world to discuss whether there are viable, economic alternatives to MB at the conference ‘Fumigants and soil sterilants: viable, economic alternatives to methyl bromide – myth or reality?’ held on 12 February 2002 at SCI Headquarters, London.

MB is a toxic greenhouse gas. The audience were told that the decision to ban it was political rather than technical – ensuring that one greenhouse gas is removed from the developed world by 2005 and from the developing world by 2015. Maurice Myers of Bromine and Chemicals Ltd, UK told the meeting that the worldwide MB market is valued at about US$600 million, but only a fraction of the amount released into the atmosphere is manufactured – decaying vegetation, primarily seaweed, produces the vast majority of emissions.

Independent consultant Del Norton covered the use of MB in agriculture and other areas. He described how MB removes alien, invasive species of insects, rodents and fungi from imported produce; protects historical memorabilia in museums and stately homes; removes living contaminants from stored fresh, processed and dried food; and exterminates cockroaches and rats on transport systems. Chris Bell of the Central Science Laboratory, UK and Chair of the meeting, argued that replacing MB in the non-agricultural sector may be more difficult because of its many diverse products and applications.

Legislation to reduce pesticide use, and the removal of MB will significantly lower the overall dose of pesticides used in any one country. ‘The economic impact of banning methyl bromide’ heard Jan Henfling describe how MB use in the Netherlands, at a maximum in 1985, is now zero. Agricultural systems supported by government funding have allowed this, but import controls protecting home-grown produce from cheaper produce grown in countries using MB is also necessary. David Heaton of K&S Fumigation in his session ‘Experiences in the UK’ said that there are no obvious alternatives to MB, because it works quickly, has a broad spectrum, leaves no chemical residues and is cheap. Experimental substitutes are being created, but are in the early stages of development.

In the USA, most MB is used on strawberries, tomatoes, peppers and melons. John Busacca of Dow Agrosciences, USA, told delegates that farmer investment in these crops is huge – Californian strawberry growers invest over $10,000 per acre before any fruit is picked. Loss of a valuable soil sterilant will cost the state hundreds of millions of dollars in lost sales. Joe Noling of the University of Florida, USA explained that to date, MB substitutes have been chemical, with no natural or biological agent matching the level of control of MB. To replace MB mixtures, more expensive and less effective compounds will be used, causing food quality to fall and food costs to escalate.

Lucca Lazzeri of the Institute of Industrial Crops (ISCI), Italy, explained that many plants naturally produce chemicals to protect themselves against insects and fungi. Using these plants as green manure, these toxicants can be ploughed into the soil where they act as soil sterilants. Eris Tjamos, Agricultural University of Athens, Greece continued, explaining that where there are long periods of sunshine this energy can be used to sterilise the soil (solarisation) but it takes time – weeks as opposed to days with methyl bromide. Giora Kritzman from the The Institute of Plant Protection, Israel gave details of the considerations for use of other toxins – formalin is under evaluation in Israel but very high use rates, a narrower spectrum and slower action count against it.

The conference concluded that there are no current groundbreaking solutions – but a lot of ongoing work. Horticultural crops will still be grown to a quality that is acceptable and a cost that we should be able to afford – as long as the seaweed emissions don’t overcome us first.

The SCI Pest Management Group is dedicated to all aspects of crop protection including the areas of animal and public health. The Group`s series of conferences and meetings explore many areas of crop protection including new technologies, environmental impact and the introduction of sustainable systems. The SCI Pest Management Group is also closely associated with SCI`s noted learned journal, Pest Management Science, where meeting proceedings are often published.