The long haul to rid the world of POPs

In the early hours of 10 December, 122 country delegates meeting in Johannesburg reached a 13th hour agreement for an international legally binding agreement for the elimination of POPs (Persistent Organic Pollutants). Ministers will meet in Stockholm next May to sign the Convention, then the work to rid the planet of these insidious chemicals will begin in earnest. Mark Davis reports.

Most POPs are pesticides
Of the 12 chemicals agreed upon so far, nine are pesticides; these are aldrin, chlordane, DDT, dieldrin, endrin, heptachlor, hexachlorobenzene, mirex and toxaphene. The other POPs are the industrial electrolyte PCB and the industrial by-products dioxin and furan.
    The mere fact that the international community has made the effort to create a Convention aimed at stopping production and use of POPs demonstrates the high level of concern that exists about these chemicals. Nevertheless, signing a Convention does not physically remove the chemicals, and the road to an environment free of POPs is long and full of obstacles.
    Take, for example, the exemptions some countries are seeking for certain uses of some of the chemicals. There is common agreement that endrin and toxaphene can be done away with since there is no production or use of either chemical anywhere in the world. For all other POPs some exemptions are sought by some countries. The table opposite indicates the various remaining production and use of POP insecticides(1).
    The logic behind these exemptions is that in most cases very small amounts of the chemicals are involved, they may already be in use for example as impregnated telegraph poles or buried with cables and their removal would be too costly, or they are used in closed systems that do not allow release to the environment. Under the agreed convention text, these exemptions are now permitted, and it could be argued that the new POPs convention will actually make no difference to the status quo of POPs production and use. 
    Perhaps the Convention will raise political and public awareness that will lead to faster removal and replacement of POPs still in use. The Convention will also set dates for final expiry or review of these exemptions, but it remains to be seen whether these will be enforced.

Piles of POPs
While production and use of some POPs to some degree continues, the biggest problem lies in the identification, safeguarding and appropriate treatment of stockpiles of POPs. To begin with little is known about the location, size and condition of existing stockpiles. Efforts are being made by the UN Food and Agriculture Organisation (FAO) and Environment Programme (UNEP) to help countries to identify their stockpiles of POPs and other obsolete chemicals, but progress is slow and the data emerging from these exercises is not always accurate. 
    The emerging picture is one of a problem of overwhelming proportions, and as more data emerges, the bigger the problem becomes. FAO’s work to identify obsolete pesticide stocks in Africa and the Near East initially identified approximately 20,000 tonnes. That estimate has now grown to 47,000 tonnes(2). This total includes many pesticides that are not POPs, but it is irrational to pick out POPs for action and leave other obsolete and in many cases leaking pesticides in place. 
    In the CIS (Commonwealth of Independent States) region, work to complete inventories of obsolete pesticides and persistent organic pollutants (POPs) has been supported by UNEP Chemicals. Early indications suggest that very large stockpiles exist (see also pages 8-9). Anecdotal reports suggest that around 70-100,000 tonnes of obsolete pesticides are held in these countries(3), but it is not yet clear what proportion of these are POPs.
    In other regions such as Asia, little information is available at present, but work is progressing. 
In general it is estimated that 20-30% of all obsolete pesticide stockpiles are POPs. Virtually all developing countries and economies in transition hold obsolete pesticides stockpiles. Countries that previously operated centralized supply mechanisms tend to have larger stockpiles, often reaching tens of thousands of tonnes. In total it could be estimated that global obsolete pesticides stockpiles in developing countries and economies in transition amount to something in the order of 400,000-500,000 tonnes, of which 80,000-150,000 tonnes could be POPs. 
    None of this information takes account of PCBs which are stockpiled or continue to be used in electrical equipment around the world in volumes that dwarf those of obsolete pesticides. Russia alone estimates that it has something in the region of 4-500,000 tonnes of PCBs(4), and it is clear from preliminary country reports from other regions that the problem is equally serious elsewhere. 

Global elimination of POPs
The information available so far is sparse but significant:

• The problem is of gargantuan proportions, but cannot be quantified;

• The problem is global;

• Many of the chemicals are widely dispersed in the environment as products in use, stockpiles of unused chemicals or as residual contaminants;

• POPs are often present with other non-POP chemicals. Any solutions applied to POPs will almost certainly need also to be applied to these other chemicals;

• POPs in use need to be replaced with other pest management solutions – chemical or otherwise;

• solutions will be expensive and complex.

This list is enough to send donors and international fundholders running for cover in expectation of a black hole evolving that will swallow money and old chemicals endlessly. Fear of the problem is no bad thing, and action to develop, fund and implement solutions has already started.
    UNEP Chemicals is running a project aimed at determining the scope of the POPs problem on a regional basis, and a second project designed to assess the needs of developing countries in solving their POPs problems. FAO continues with its work on completing inventories of obsolete pesticides and the UN Institute for Training and Research (UNITAR) helps countries to assess their chemical management needs and prioritise issues for action. 
    A recent conference on obsolete pesticides held in Washington brought together donors, developing countries, industry and NGOs to discuss how this massive global problem could begin to be solved. Among a number of recommendations that focused heavily on preventing any recurrence of the problem in the future, there was widespread agreement that a system of prioritisation needs to be put in place. This would place demands on countries seeking support, requiring them to demonstrate that political and institutional support for solutions existed and that effective prevention measures were in place. Such measures might include regulatory controls and IPM policies(5).
    These processes will help to advance strategies and mechanisms, but they will not yet bring about the destruction of POPs or other waste chemicals. For this, appropriate technological solutions are needed. Existing technology does not offer appropriate solutions to the POPs problem. Most hazardous waste destruction equipment is based on incineration in some form. Incinerators convert chemicals in the presence of oxygen into other chemicals that may be harmless such as carbon dioxide or water, or may be extremely harmful such as dioxins and furans. Controls to prevent harmful emissions are not always effective. In addition, existing incinerators that are permitted to import waste for destruction are only present in Europe. This means that waste must be transported by sea to reach them, at high cost and with the risk of marine pollution.
    Using locally available facilities such as cement kilns, foundries, hospital incinerators or other installations will almost inevitably lead to incomplete destruction, creation of POP by-products and additional pollution. In effect, the problem will be made worse.
    Is it possible to destroy POPs without creating greater risks? It seems that the technology exists, for example in the form of base-catalyzed dechlorination or gas-phased hydrogenation technology, but it is expensive and does not have enough of a proven track record to give developing countries the confidence to allow its use on their land. There are also limitations such as infrastructure needs and economies of scale that may make it impractical to use certain technologies in many countries. 
    A new NGO initiated project supported by UNDP and implemented by UNIDO will explore the feasibility of using these non-incineration POP destruction technologies in developing countries. Many hope that the results will be positive, but the pilot projects will take a number of years to complete. Meanwhile the most widely used form of destruction for POPs and other chemical wastes will remain incineration.

Where do we go from here?
Existing financial and technological capacity for dealing with POPs will be overwhelmed unless an efficient system of prioritisation is developed. This prioritisation will need to account for risk assessment of the existing problems and also preparedness and commitment on the part of the countries wishing to solve their POPs problem. 
    Accounting for the fact that existing technology does not generally provide the best possible solution to the problem, much greater efforts need to be invested in developing and implementing better solutions based on emerging technology, avoiding long distance transportation of waste, and ensuring that a solution to one problem does not create another.
    Most importantly, the international community that is now struggling to solve this immense problem of POPs and obsolete pesticides must learn and act upon the lesson being taught: Complete reversal of the global environmental disaster that is POPs is nigh on impossible. Today we are called upon to deal with chlorinated POP chemicals. Perhaps in the near future we will need to address endocrine disrupting pesticides and plastics, and later still perhaps genetically modified organisms. Prevention is definitely better than struggling to cure a problem that has no real cure.

References
1. Preparation of an international legally binding instrument for implementing international action on certain persistent organic pollutants, Draft text by the Intergovernmental Negotiating Committee Chair, UNEP/POPS/INC.5/5, 3 August 2000.
2. Baseline Study on the Problem of Obsolete Pesticide Stocks, Mark Davis, On behalf of OECD Pesticides Working Group, FAO Obsolete Pesticides Project, UNEP Chemicals, Secretariat of the Basel Convention, August 2000.
3. Proceedings of the subregional expert meeting on technologies for treatment/destruction of PCBs and obsolete pesticides, Russian Federation 6-9 July 1999, UNEP Chemicals/CIP State Committee of the Russian Federation on Environmental Protection.
4. Ibid.
5. OECD/FAO/UNEP Conference on Obsolete Pesticides, Virginia, 13-15 September 2000.

[This article first appeared in Pesticides News No.50, December 2000, p6-7]