As the detailed information given in the previous chapter shows, there are MB alternatives that are cheaper, others that are more or less equal and still others that are more expensive than MB. Many factors influence local prices. The facts from chapter 3 allow, however, the identification of alternatives that are economically viable under varying conditions.
Examples of treatments that are more expensive than MB include chemicals like Dazomet in Colombia (over 3 times more expensive) and mixtures containing chloropicrin and several other pesticides in the USA (2-2.5 times more expensive) (Prospect Consulting, 1997).
Cheaper alternatives are solarisation for tomato es in Italy (one third of the cost of MB treatment) and in Florida, composting and IPM for cut flower production in Colombia (about 72 % cheaper), alternative pesticides for strawberries in the Netherlands (about 80 % cheaper), and rock wool for cucumberscucumber cucumber in the Netherlands (about 90 % cheaper) (Prospect Consulting, 1997).
In most cost comparisons of quarantine treatments, only costs of MB fumigation itself are taken into consideration. It should not be forgotten, however, that additional hidden costs may be involved especially in cases where correct use is neglected. These costs include losses due to reduction in the quality of fruit and vegetables after MB fumigation or costs associated with redirecting produce that is not accepted on the original target market because of damage related to MB treatments (Lay-Yee, 1997). In such cases, several alternatives prove to be cheaper than MB fumigation.
It is highly probable that the fine-tuning of alternatives for commodity and structural treatments will cause future decreases in price. Many alternatives will thus become competitive that nowadays are still more expensive than MB.
Changes in yields have frequently been reported in connection with MB alternatives. In some cases decreases occur, but many alternatives do not affect yields or contribute to considerable increases that outweigh higher application cost in some cases.
Decreases in yields have been reported from California in tomato es and strawberries treated with 1,3-D and other chemical substitutes for MB (Prospect Consulting, 1997). Equal or increased yields are described for many non-chemical alternatives in the production of strawberries, tomato es, cucurbits 2 and other vegetables. These alternatives include soilless culture, solarisation and various IPM schemes in the EC, the USA and Nordic countries. Yield increases may vary from about 20 % to 100 % (Prospect Consulting, 1997).
Some alternative post-harvest treatments for perishable perishables perishables commodities increase shelf life and enhance fruit quality like controlled atmospheres for certain fruits.
Estimates of the economic impact of the MB phase-out vary widely. Ristaino & Thomas (1997) compare economic loss figures given for the USA by the National Pesticide Impact Assessment Program (NAPIAP) and the Environmental Protection Agency (EPA). Whereas NAPIAP estimated annual economic losses of 1.3 to 1.5 billion USD if a ban on MB occurred in the USA, EPA estimated a benefit of 1.2 to 2.3 USD in the case of an MB phase-out. Positive effects on human health are not included in the EPA figure.
There is strong evidence that some alternatives for soil treatment like, for example, solarisation plus IPM present considerable net benefits for many crops in warm climates. Examples include the production of tomato es and other vegetables in the EC and the USA. In greenhouses, increases in profits of about 15-20 USD/m² have been reported for cucumberscucumber cucumber and strawberries (Prospect Consulting, 1997).
The economic facts listed in chapter 3 and sections 4.1 - 4.3 demonstrate that MB is a red herring in the discussion relating to the competition. For example, the two leading cut flower exporting nations, the Netherlands and Colombia, have largely eliminated MB application whereas the Government of Kenya, the third biggest exporter, still resists a rapid phase-out. These economic facts encourage GTZ to strongly support the efforts of A5 countries to phase out MB as soon as possible (cf. also chapter 8).
Many of the alternatives in soil treatment are more labour-intensive than the use of MB and thus may have a positive impact on rural labour markets. Additionally, new service and job opportunities will arise, for example in the supply of growth substrates or compost, monitoring, diversification of pest control services, production of biological control agents and training and consulting services.
Furthermore, switching from production systems dependent on imported MB to labour-intensive systems using local resources would have the positive effect of stabilising the national economies of A5 countries.
The detrimental effects of MB described in chapter 1 cause high costs that must be carried by society. These costs include cases of diseases associated with exposure to UV-B radiation and damage in agriculture, forestry, fishery and building materials. A study commissioned by the Canadian Government calculates these costs excluding health damage to be 459 billion USD for the period from 1987 to 2060 (ARC, 1997). It can be concluded that about 5-10 % of these costs are associated with MB use by man.
Other externalised costs relate to environmental impacts of MB application in the soil (including residues and metabolites) on beneficial organisms like earthworms and disease-inhibiting microorganisms and occasionally phytotoxic effects on crops. Some of the consequences are increases in Pythium and Fusarium wilt levels, mycorrhizal deficiencies and reduction of enzymatic activities of soil microorganisms like Nitrosomonas and Nitrobacter that leads to nitrogen leaching. Effects of residues and metabolites in water and food as well as air contamination are poorly understood and in spite of strict regulations in industrialised countries excessive levels have repeatedly been reported (Prospect Consulting, 1997).
Hidden costs are often neglected in economic considerations concerning MB alternatives. Food produced with MB is actually more expensive than it appears if market prices are taken as a basis. Reduction of hidden costs through the substitution of MB may make government funds available for further support of research on and implementation of alternatives.
The results of the study commissioned by the Canadian Government (ARC, 1997) indicate clearly the overall benefits of the MP. The findings leave no doubt that the MP has significant net benefits. The costs have been precisely determined by an international panel of experts and the part of the benefit that can be safely assessed amounts to 224 billion USD for the period between 1987 and 2060. This calculated net benefit underrates actually the value of the MP as human health and some other benefits have not been identified.
Taking into account the proportion of anthropogenic MB in ozone depletion it can be estimated that 5-10 % of the total benefit is related to the substitution of this gas. This corresponds to an amount of 11 to 22 billion USD plus human health benefits for the period between 1987 and 2060. Due to the short-term benefits of MB substitution mentioned in chapter 2, the economic benefits would ensue faster than with CFCs and some other ozone-depleting substances.
