Persistent Organic Pollutants in Marine Ecosystems Persistent Organic

Persistent Organic Pollutants in Marine Ecosystems

Persistent Organic Pollutants • Fate of Po. Ps • Mechanisms of Environmental Control • Characteristics • Main groups • Issues

pcwww. liv. ac. uk/aquabiol/BIOL 415_Web/

Tri-Butyl Tin • Nucella • Imposex

Halogenated Aromatic Hydrocarbons Chlorine Bromine Fluorine

Types of Po. P • Pesticides • Industrial Chemicals • By-Products

Associated Issues • Bioaccumulation – Biomagnification • Loss of higher predators • Adverse impacts on marine food chains • Fish eating – Gt Lakes of North America, Baltic & North Sea • Birth defects, reduced aptitude in new born babies • Endocrine Disruption

Stockholm Convention UNEP decided to convene an Intergovernmental Negotiating Committee (INC) to prepare an legally binding instrument on persistent organic pollutants (POPs). The INC completed work on the instrument, the Stockholm Convention on Persistent Organic Pollutants, in December 2000.

Stockholm convention The Convention entered into force on 17 May 2004. The first meeting of the Conference of the Parties took place from 2 -6 May 2005 in Punta del Este, Uruguay

Po. Ps in Swedish Breast Milk

Toxicity of Po. Ps • Related to structure • Related to ‘most toxic substance’ – 2, 3, 7, 8 tetrachloro dibenzo dioxin • Toxicity Equivalent - TEQ – Relative Factor of 1 for 2, 3, 7, 8 TCDD

Dioxins/Furans • 75 individual chlorinated dioxins • 135 individual chlorinated furans • Very stable & bind to soils and sediment

DDT • Old problem – Peregrine Falcons etc • Residues remain • DDE – oxidative environments • DDD – reducing environments • Mersey estuary and Irish Sea

PCBs – Major Problems • Baltic Sea & North Sea • Gt Lakes of North America • Hudson River • Local “difficulties” : – Mersey Estuary & Liverpool Bay

Poly Chlorinated Biphenyls • 209 Compounds - ca 100 in env

PCB • Congener 209 – Deca-choro biphenyl

Poly Chlorinated Biphenyls • • 209 Compounds - ca 100 in env Highly inert Introduced 1930 s Discovered in environment 1966 by Jensen in Sweden during analysis for DDT • 750, 000 tonnes manufactured

Poly Chlorinated Biphenyls • Banned by USEPA in new uses in 1979 • Manufacture completely banned in 1984

Poly Chlorinated Biphenyls • Technical Mixtures – Arochlor 1242 – Arochlor 1254 – Arochlor 1262

PCBs

Brominated Fire Retardents • Poly brominated diphenyl ethers (PBDEs) • 209 Congeners

Brominated FRs • Among the many BFRs used in the world the main commercial BFRs are the following: • TBBPA: Tetrabromobisphenol -A • HBCD: Hexabromocyclododecane • PBB: Polybrominated biphenyls Phased out in Europe

PBDEs • Deca-BDE (Decabromodiphenyl ether) • Octa-BDE (Octabromodiphenyl ether) - Phased out in Europe • Penta-BDE (Pentabromodiphenyl ether) - Phased out in Europe

Flame Retardents • Polybrominated diphenyl ethers

Other Brominated materials: • Brominated polymers such as brominated epoxy, brominated polystyrene, brominated polycarbonate, poly (brominated acrylate), and brominated polyols.

Mersey Estuary • High levels of BDEs especially : Deca. Bromo. Diphenyl. Ether 209 • On-going research

Po. Ps: Impacts of tissue residues Endocrine Disruption

Intersex Mersey Male Flounder Gonad Intersex Flounder

Endocrine Disruption • Molluscs –– TBT - IMPOSEX

Nucella