Ministers and officials from 150 governments are meeting in May to advance global efforts to rid the world of some of the most hazardous chemicals produced by humankind; the talk are to spotlight nine new chemicals, alternatives to DDT and the challenges of a (Persistent Organic Pollutants) POPs-free futureThe conference runs from 4 to 8 May at the Geneva International Conference Center or CICG, 15 rue de Varembé, Geneva, Switzerland. The conference marks a new chapter in the history of the Stockholm Convention. For the first time, nine new chemicals are proposed for listing many of which are still widely used as pesticides, flame retardants and a number of other commercial uses.
These are Alpha hexachlorocyclohexane; Beta hexachlorocyclohexane; Hexabromodiphenyl ether and heptabromodiphenyl ether; Tetrabromodiphenyl ether and pentabromodiphenyl ether; Chlordecone; Hexabromobiphenyl; Lindane; Pentachlorobenzene; Perfluorooctane sulfonic acid, its salts and perfluorooctane sulfonyl fluoride.
While the POPs risk level varies, all of these chemicals share four properties: they are highly toxic; they are stable and persistent, often lasting for decades before degrading into less dangerous forms; they evaporate and travel long distances through air and water; and they accumulate in the fatty tissue of humans and wildlife.
Worldwide, every person carries traces of POPs in his or her body. POPs circulate globally through a process known as the "grasshopper effect". POPs released in one part of the world can, through a repeated process of evaporation and deposit, be transported through the atmosphere to regions far away from the original source.
Until now, the Stockholm Convention on Persistent Organic Pollutants (POPs) has targeted the so-called “dirty dozen”: 12 hazardous pesticides and industrial chemicals that are linked with human health impacts ranging from damage to the nervous and immune systems, cancer and reproductive disorders and the disruption of infant and child development.
“The risks posed by such chemicals are profound and these toxic substances leave chemical footprints around the globe. Farmers, pregnant women, young people, the unborn and certain remote communities such as those in the Arctic are particularly vulnerable,” said UN Under-Secretary General and UNEP Executive, Achim Steiner.
“In Geneva governments can make an important contribution to the poverty-related UN Millennium Development Goals as well as catalyzing a transition to a healthier, more sustainable Green Economy. I would urge them to take that opportunity and begin lifting another health threat from literally millions of peoples’ lives,” he added.
Fortunately, alternatives to POPs do exist. The problem has been that high costs, a lack of public awareness, and the absence of appropriate infrastructure and technology have often prevented the adoption of alternatives. The selection of any alternative will depend on the specific target chemical, the properties and use patterns of that chemical and each country's climatic and socio-economic conditions.
A key issue on the conference agenda will be an evaluation of whether countries that use DDT to combat mosquitoes carrying the deadly malaria parasite need to continue doing so. DDT - dichloro-diphenyl-trichloroethane - was developed as an insecticide in the 1940s, and was widely used during World War II to combat insect-borne diseases. While the Convention targets DDT for elimination, it recognizes that some countries must still use this pesticide to protect their citizens’ health.
Delegates will consider the endorsement of a business plan to promote effective alternatives to DDT. The meeting will also focus on expanding support to developing countries to clean up POPs worldwide and safer alternatives for human health and the environment.
Another issue is how to meet the challenges of a POPs-free future to minimize human suffering and the global cost of responding to the human health and environmental problems caused by POPs. This is particularly important to vulnerable populations which suffer the most exposure. There are four distinct challenges:
- Challenge #1: moving away from the production and use of POPs towards safer alternatives and to reach the goal of eliminating the release of unintentionally produced POPs.
- Challenge #2: identifying new POPs that put human health and environment at risk.
- Challenge #3: ensuring that technical and financial resources are made available for all countries to meet their obligations under the Convention.
- Challenge #4: continuing to ensure the Convention meets its goal of protecting human health and the environment from POPs.
Another issue is how to strengthen the efforts to phase out PCB use. A vital next step will be to consider the endorsement of a PCB elimination club to establish key data and to evaluate whether the use of PCBs is indeed declining.
PCBs - polychlorinated biphenyls - are synthetic (human-made) chemicals first produced in the late 1920s. They were used as cooling fluids in electrical equipment and machinery because of their durability and resistance to fire.
The meeting will also consider further steps for promoting the use of best available techniques, best available practices and best environmental practices to reduce or eliminate the unintentional releases of unintentionally produced POPs.
The Stockholm Convention
The Stockholm Convention on Persistent Organic Pollutants is a global treaty to protect human health and the environment from chemicals that remain intact in the environment for long periods, become widely distributed geographically and accumulate in the fatty tissue of humans and wildlife.
Exposure to Persistent Organic Pollutants (POPs) can lead serious health effects including certain cancers, birth defects, dysfunctional immune and reproductive systems, greater susceptibility to disease and even diminished intelligence. Given their long range transport, no one governing acting alone can protect is citizens or its environment from POPs.
In response, the Stockholm Convention, which was adopted in 2001 and entered into force 2004, requires Parties to take measures to eliminate or reduce the release of POPs into the environment. The Convention is administered by the United Nations Environment Programme and based in Geneva, Switzerland.
The nine new chemicals proposed for listing under the Stockholm Convention are:
- Alpha hexachlorocyclohexane to Annex A;
- Beta hexachlorocyclohexane to Annex A;
Although the intentional use of alpha- and beta-HCH as an insecticide was phased out years ago, these chemicals are still produced as an unintentional by-product of lindane. Approximately 6-10 tons of other isomers including alpha- and beta-HCH result from each ton of lindane produced. - Hexabromodiphenyl ether and heptabromodiphenyl ether to Annex A;
- Tetrabromodiphenyl ether and pentabromodiphenyl ether to Annex A;
Bromodiphenyl ether congeners are a group of brominated organic substances that inhibit or suppress combustion in organic material, which are used as additive flame retardants. Brominated diphenyl ethers are mainly manufactured as commercial mixtures where several isomers, congeners and small amounts of other substances occur. - Chlordecone to Annex A;
Chlordecone is a synthetic chlorinated organic compound, which was mainly used as an agricultural pesticide. It was first produced in 1951 and introduced commercially in 1958. Current use or production of the chemical is not reported. - Hexabromobiphenyl to Annex A;
Hexabromobiphenyl (HBB) is an industrial chemical that was used as a flame retardant, mainly in the 1970s. Based on existing data, HBB is no longer produced or used in most countries. - Lindane to Annex A;
Lindane was used as a broad-spectrum insecticide for seed and soil treatment, foliar applications, tree and wood treatment and against ectoparasites in both veterinary and human treatments. Lindane production has decreased rapidly in recent years and only a few countries still produce it. - Pentachlorobenzene to Annex A and C;
Pentachlorobenzene (PeCB) was used in PCB products, dyestuff carriers, as a fungicide, a flame retardant and a chemical intermediate such as the production of quintozene and it may still be used for this purpose. PeCB is also produced unintentionally during combustion in thermal and industrial processes. It appears as an impurity in products such as solvents or pesticides. - Perfluorooctane sulfonic acid, its salts and perfluorooctane sulfonyl fluoride to Annex A or B;
PFOS is both intentionally produced and an unintended degradation product of related anthropogenic chemicals. The current intentional use of PFOS is widespread and found in products such as in electric and electronic parts, fire fighting foam, photo imaging, hydraulic fluids and textiles. PFOS are still produced in several countries today.
The 12 initial POPs covered by the Convention include nine pesticides (aldrin, chlordane, DDT, dieldrin, endrin, heptachlor, hexachlorobenzene, mirex and toxaphene); two industrial chemicals (PCBs as well as hexachlorobenzene, also used as a pesticide); and the unintentional by-products, most importantly dioxins and furans.
No comments:
Post a Comment