The Dirty Dozen

Barriers to Pollution Prevention ( The Dirty Dozen ) There are numerous reasons why more businesses are not reducing the wastes they generate. The following dirty dozen are common disincentives ... 

Reduced wa.ste-treatment co.sts. As discussed in reason no. 5 of the dirty dozen, the increasing costs of traditional end-of-pipe waste-management practices are avoided or reduced through the implementation of pollution-prevention programs. 

A list of hazardous environmental chemicals, sometimes referred to as the dirty dozen, has been drawn up by the United Nations Environment Programme (UNEP). These are ... 

Chlorinated micropoUutants are harmful for man and environment due to their toxicity, persistence, and bioaccumulation. Persistent compounds are very stable and difficult to get metabolized and mineralized by biological and chemical processes in the environment, and as a result, they have become ubiquitous in water, sediments, and the atmosphere bioaccumulation is the result of the lipophilicity of these compounds. Polychlorinated dibenzodioxins and -furans (PCDD/F) are not produced purposely like many of other chlorinated technical products, such as chlorinated biocides DDT, lindane, and toxaphene. The production and use of persistent organic pollutants (POPs), the dirty dozen has now been banned worldwide by the Stockholm protocol. It should be mentioned that about 3000 halogenated products have now been isolated as natural products in plants, microorganisms, and animals," but the total amount of these products is much smaller compared to xenobiotics. 

These two positions were in conflict in 2001 when representatives from 127 nations met in Stockholm to consider a universal ban on 12 TOCs, commonly known as the "dirty dozen." The dirty dozen includes aldrin, chlordane, dieldrin, DDT, endrin, heptachlor, hexachlorobenzene, and Mirex. After extended discussion and debate, representatives adopted a final document now known as the Stockholm Convention on Persistent Organic Pollutants. The document was signed on May 22, 2001, and entered into force on May 17, 2004, at which point the required minimum of 50 nations had ratified the treaty. 

The POP protocol elaborated on occasion of the Stockholm Convention in 2001 contained 12 compounds, known as the dirty dozen aldrin, chlordane, DDT, dieldrin, endrin, heptachlor, HCB, mirex, PCBs, pol veil I orod i be nzo-/ -d i ox ins. polychlorodibenzofurans and toxaphene. After several years of implementation other compounds, were also included HCHs, PAHs, certain brominated flame retardants, perfluorooctanesulfonic acid (PFOS) and pentachlorobenzene (http // www.chem.unep.ch/pops/). This protocol is aimed to control, reduce and/or eliminate discharges, emissions and spills of POPs into the environment. 

The Stockholm Convention is a global treaty committing the international community to protecting human health and the environment from the potentially harmful effects of POPs (UNEP Chemicals, 2005). The United Nations Environment Programme (UNEP) has identified 12 most toxic POPs (the Dirty Dozen ) for control under the Convention, including 10 intentionally produced POPs pesticides/industrial chemicals (aldrin, chlordane, DDT, dieldrin, endrin, heptachlor, hexachlorobenzene (HCB), mirex, toxaphene and polychlorinated biphenyls (PCBs)) and two unintentionally produced POPs by-products (polychlorinated dibenzo-/ -dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs)). In implementing the Convention, Parties to the Convention will take measures to restrict the trade, production and use of the intentional POPs and to reduce and, where possible, to ultimately eliminate the production and release of the unintentional POPs by-products. 

The global POPs agreement initially covers the dirty dozen, which includes nine pesticides (aldrin, chlordane, DDT, dieldrin, endrin, heptachlor, hexa-chlorobenzene, mirex, and toxaphene), and three industrial chemicals (PCBs) and unintentional by-products (dioxins and furans) of industrial and combustion... 

Fig. 2.2 The dirty dozen of persistent organic pollutants (POPs) and effects of photo-initiated processes (and of AOPs/AOTs in general) generating a convenient sink.

Member of the Dirty Dozen (see chapter 1.2) 2> Solvent, technical fluids 3> Synthetic polymer 4> X-ray contrast media s> Pharmaceutical... 

Fig. 2 Molecular structures of the Dirty Dozen. 1 - Polychlorinated dibenzo-p-dioxines, PCDD 2 - Polychlorinated dibenzofuranes, PCDF 3 - Polychlorinated biphenyls, PCB 4 - Hexachlorobenzene, HCB 5 - 2,2-Bis(4-chlorophenyl)-l,l,l-trichloroethane, DDT 6 - Toxaphene 7 - Aldrin 8 - Dieldrin 9 - Endrin 10 -Chlordane 11 - Heptachlor 12 - Mirex.

The environmental relevance of the POPs leads to the ban of the most important representatives, the Dirty Dozen, by the Stockholm Convention in May 2001 (see also http Wwww.pops.int ). Prior to the prohibition of production and emission of these Dirty Dozen numerous scientific investigations considering the occurrence and fate of these compounds especially in the aquatic environment were performed (see also Jones and Voogt 1999). 

In 1972, the U.S. Environmental Protection Agency announced that DDT could no longer be used in the United States because of the risk it posed for human health and the environment. A number of other developed nations soon followed the EPA s action. In 2001, a conference sponsored by the United Nations, called the Stockholm Convention on Persistent Organic Pollutants, adopted a statement calling for the eventual elimination of a dozen pesticides, known as the dirty dozen, including DDT. Because of its effectiveness against malaria and other infectious diseases, DDT was given a waiver for use by public health officials in nations where the compound had not been banned. 

Demise of the Dirty Dozen , Global Pesticide Campaigner, 1995, Vol.5 No.3 Somalia... 

The EPA provides a list of twelve particularly persistent organic pollutants to watch out for. The list includes aldrin, chlorodane, dichlorophenyl trichloroethane (DDT), dield-rin, endrin, heptachlor, hexachlorobenzene, mirex, toxaphene, polychlorinated biphenyls, polychlorinated dibenzo-p-dioxins, and polychlorinated dibenzofurans. The EPA has colloquially named this group of compounds as the dirty dozen. ... 

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