MLTN Pollution

8/8/2019 MLTN Pollution

1/22

THE MARINE BIOLOGICAL ASSOCIATION OF THEUNITED KINGDOM

The Marine Life Information Network for Britain andIreland

Marine Life Topic Note

MARINE POLLUTIONPrepared by: Olwen Ager and Rebecca Jefferson

Last updated: October 2005

Definition -Marine pollution the introduction by man, directly or indirectly, of substances orenergy into the marine environment (including estuaries) resulting in such deleterious effectsas harm to living resources, hazards to human health, hindrance to marine activities includingfishing, impairment of quality for use of seawater, and reduction of amenities (GESAMP,1983).

INTRODUCTION

Pollution in British estuaries and coastal waters has been studied for over 100 years. Untilthe 1970s the major pollutant considered was organic waste (sewage). Improved sewagetreatment in the last 30 years and possibly increased use if chemicals in the marineenvironment have meant that the impacts of other pollutants have started to come to light(Matthiessen & Law, 2002). Marine pollution is a very broad topic, so we have divided thetopic into the following areas:

1. Sewage and other nutrients

2. Oil

3. Chemicals

4. Noise

General Links for further information

Ask a Scientist marine pollution http://oceanlink.island.net/ask/pollution.html

Department for Environment Foodand Rural Affairs

http://www.defra.gov.uk

Global Program of Action for theProtection of Marine Environmentfrom Land Based Activities

http://www.gpa.unep.org

Greenpeace http://www.greenpeace.org/international/

International MaritimeOrganisation http://www.imo.org

Marine Conservation Society http://www.mcsuk.org

Ocean Planethttp://seawifs.gsfc.nasa.gov/OCEAN_PLANET/HTML/peril_pollution1.html

Worldwide Fund for Nature(WWF)

http://www.wwf.org.uk/core/wildlife/fs_0000000040.asp


2/22

Marine Life Topic Note Marine Pollution

Visit the Learning Zone at http://www.marlin.ac.uk/learningzone

SEWAGE AND OTHER NUTRIENTS

History

For centuries, the seas have been viewed as a bottomless pit for human derived waste. Untilrecently, many coastal towns in the UK had little or no treatment of sewage and it was

common for raw sewage to be discharged directly into the marine environment (YorkshireWater, 2002). A more recent source of nitrification of the inshore waters is agricultural run-off, especially from application of fertilizers.

Importance

It is an unavoidable fact of nature that humans produce waste so there will always be a needto dispose of sewage. European legislation, public concern about public health and on thestate of beaches, and campaigning by such groups as Surfers Against Sewage has led toimproved treatment of sewage (SAS, 2002).

How is sewage treated?

Every day in the UK, 347,000 km of sewers (enough to go round the earth 9 times) collect 11billion litres of waste water (sewage). This waste is treated in over 9,000 sewage treatmentplants before being discharged to inland waters, estuaries and the sea (Defra, 2002).

The organic nature of sewage means that it is subject to break down by bacteria. Bacteriarequire oxygen to do this. If large amounts of untreated sewage are discharged into the sea,or water body of restricted circulation such as a river or estuary, the amount of dissolvedoxygen in water is reduced. In extreme cases, fish and other aquatic life will find it hard tosurvive. Therefore, sewage is treated to reduce the amount of organic substances and toprotect the environment against these effects (Defra, 2002) (Figure 1).

11%

55%

21%

13%

Preliminary / no treatment Primary treatmentSecondary treatment Tertiary treatment

Preliminary treatment:involves screening thesewage to remove largesolids, it may also include gritremoval.

Primary treatment: involvesthe removal of debris and theseparation of water andsludge.

Secondary treatment: usesbacteria to break downorganic material.

Tertiary treatment: mayinvolve ultra-violet treatmentsto reduce pathogenic bacteria

and viruses and/or nutrientremoval to preventeutrophication, and/or removalof specific toxic substances

Figure 1. Sewage treatment in the UK (MCS, 2002)

Sewage sludge

The sewage treatment process produces a large amount of sewage sludge. Historically onequarter of this sludge was dumped at sea. However, in 1998, this practice became illegaland alternatives have had to be sought. Sludge is most often used as a soil conditioner or as


3/22



a fertiliser on agricultural land. The Sludge (Use in Agriculture) Regulations 1989 regulatethe use of sewage sludge and a voluntary agreement (the Safe Sludge Matrix) ensures thatsludge is only used on certain crops. Studies have also shown that sludge can be made intobricks to build houses (New Scientist, 2002) and burnt as a fuel.

Problems

The breakdown of sewage by bacteria reduces the concentration of oxygen in the watermeasured as Biological Oxygen Demand (BOD) (Clarke, 1997). A high BOD can lead toplants and animals being starved of oxygen. Reduced oxygenation (hypoxia) can lead to achange in the infaunal benthic community, and in severe cases the death of many benthicinvertebrate species. Nutrient enrichment by sewage can stimulate the growth ofphytoplankton as well as opportunistic benthic seaweeds such as Enteromorpha, Cladophoraand Ulva, which can form dense mats. These mats can reduce the exchange of waterbetween the sediment and water column resulting in de-oxygenation of the sediments. Thefeeding areas for fish and birds may also be diminished if there is an extensive coverage ofalgal mats on intertidal sediments (Cole et al., 1999). Absence of solids but continuedpresence of high levels of nutrients, especially in enclosed areas, can result in blooms of

algae including some that are poisonous. An increased occurrence of paralytic and diureticshellfish poisoning may result from such increase in nutrients.

Unless sewage has had tertiary treatment (i.e. ultraviolet treatment or microfiltration) it cancontain a number of strains of human derived bacteria and viruses including those causinggastro-enteritis, botulism, hepatitis A and meningitis. Studies have found that the hepatitis Avirus can survive in salt water for approximately 100 days (SAS, 2002).

Filter feeding shellfish, such as mussels and oysters, grown in sewage contaminated watersmay cause food poisoning. Bacteria and viruses can become concentrated in the flesh of theorganism and are transferred to humans if they eat raw or inadequately cooked shellfish(Clarke, 1997).

LocationThe Good Beach guide produced annually by the Marine Conservation Society gives detailsof beaches that are not affected by inadequately treated sewage discharges (MCS, 2005).Yorkshire, Anglian and Welsh Water all treat their sewage to tertiary level, therefore removingthe majority of bacteria and viruses (Yorkshire Water, 2002; SAS, 2002).

Control Measures

European Bathing Water Directive (76/160/EEC).

EC Urban Waste Water Treatment Directive (91/271/EEC).

The Urban Waste Water Treatment (England and Wales) Regulations 1994

The Urban Waste Water Treatment (Scotland) Regulations 1994The Urban Waste Water Treatment Regulations (Northern Ireland) 1995

EU Nitrates Directive (91/67/EEC)

The Protection of Water against Agricultural Nitrate Pollution (England and Wales)Regulations 1996

Nitrate Pollution (Scotland) Regulations 1996

The Protection of Water against Nitrate Pollution (Northern Ireland) Regulations 2003

Sludge (use in Agriculture) Regulations 1989


4/22



The Food Safety (Fishery Products and Live Shellfish) (Hygiene) Regulations 1998

REFERENCES

Brina, G., & Pollard, S., 1999. Marine Conservation the UK Action Guide. Ross-on-Wye:Marine Conservation Society.

Clark, R.B., 1997. Marine Pollution (4th

Edn). Oxford: Clarendon Press.Cole, S., Codling, I.D., Parr, W. & Zabel, T., 1999. Guidelines for managing water quality

impacts within UK European Marine Sites. Natura 2000 report prepared for the UK MarineSACs Project. 441 pp.

Department for Environment Food and Rural Affairs (Defra), 2002. Sewage Treatment in theUK: UK Implementation of the EC Urban Waste Water Treatment Directive[on-line].London: Department for Environment Food and Rural Affairs, [cited 21/10/02]. Availablefrom:

GESAMP (1983). Report of the Thirteenth Session, Geneva, Switzerland, 28. February-4March 1983. IMO/FAO/UNESCO/WMO/WHO/IAEA/UN/UNEP Joint Group, of Experts onScientific Aspects of Marine Pollution. Reports and Studies (18):50p. WMO,Geneva,

Switzerland.

Marine Conservation Society (MCS), 2002. Sewage Treatment[on-line]. Ross on Wye:Marine Conservation Society, [cited 21/10/02]. Available from:

Marine Conservation Society (MCS), 2005. Good Beach Guide 2003[on-line]. Ross-on-Wye:Marine Conservation Society, [cited 30/04/04] Available from:

Matthiessen, P. & Law, R.J., 2002. Contaminants and their effects on estuarine and coastalorganisms in the United Kingdom in the late twentieth century. Environmental Pollution,120, 739-757.

New Scientist, 2002. Sewage sludge bulks up house bricks [on-line]. London: New Scientist,[cited 17/10/02]. Available from:

Nybakken, J.W., 1982. Marine Biology: an ecological approach. Cambridge: Harper & Row.

Surfers Against Sewage (SAS), 2002. The problem - what is the problem? [on-line]. StAgnes: Surfers Against Sewage, [cited 16/10/02]. Available from:

Yorkshire Water (2002), Coast care [on-line]. Bradford: Yorkshire Water, [cited 15/10/02].Available from:

LINKS

Bag it and Bin it http://www.bagandbin.org

Dept for Environment Farming & RuralAffairs

http://www.defra.gov.uk

Dept of Environment in Northern Ireland http://www.doeni.gov.uk

Environment & Heritage Service http://www.ehsni.gov.uk

Environment Agency http://www.environment-agency.gov.uk

Environmental Campaigns http://www.encams.org

Good Beach Guide http://www.goodbeachguide.co.uk


5/22




Ofwat http://www.ofwat.gov.uk

Scottish Environmental Protection Agency http://www.sepa.org.uk

Surfers Against Sewage http://www.sas.org.uk

Water UK http://www.water.org.ukWessex Water H2O zone http://www.wessexwater.co.uk


6/22



OIL

History

Oil pollution usually hits the headlines when a tanker breaks up or goes aground and there isa major oil spill. The worlds first major oil spill happened in March 1967 when the tanker,

Torrey Canyon, went aground off the Isles of Scilly and spilled around 119,000 tonnes of oil(IMO, 2002a). Other notable recent major oil spills around the UK were in January 1993when the Braerwent aground off Shetland spilling 85,000 tonnes of oil, and in February 1996when the Sea Empresswent aground off Milford Haven and spilt around 72,000 tonnes(Figure 2). Such spills make up less then 10% of the total amount of oil that enters our seas(MCS, 2002).

Figure 2. The Sea Empressoil spill at Dale, Milford Haven, Pembrokeshire. Image: Blaise Bullimore.

ImportanceOil and its products are fundamental to the lives of most of the worlds population. It is acritical element in world economies. The demand for oil is huge not only as a fuel for cars,ships and aircraft but also in the manufacture of plastics, road surfacing, cosmetics andthousands of other products. Some everyday products manufactured from oil or petroleumproducts include: rulers, crayons, contact lenses, cosmetics, deodorants, paint, CDs, videosand roofing tiles.

Inputs of oil to the sea

Natural seeps

Oil naturally gets into the sea through natural seeps and erosion of seabed sediments.

These seeps are natural springs that ooze oil and gas instead of water (GMOPIG, 2003a).

Land-based sources

Land-based sources include discharges of untreated sewage and storm water (urban run-off), waste water from coastal industries, operational discharges from coastal oil refineriesand vehicle exhausts (GMOPIG, 2003a). Improper disposal of car engine oil is also asource. The Environment Agency Oil Care Campaign is trying to publicise responsibledisposal of oil (www.oilbankline.org.uk).


7/22



Sea-based sources

Of the 3 billion tonnes of oil produced each year, approximately half is transported by sea(Clarke, 1997).

It is estimated that over 6 million tonnes of oil enter the sea each year, due to sea-basedactivities (GESAMP, 2000) (Figure 3). There are many sources of oil in the sea, the most

visible being large slicks from damaged tankers. This source accounts for only 2.5% of thetotal oil in the sea (Clarke, 1997). The largest sea based source of oil is from atmosphericemissions associated with transportation. Much of this is through evaporation of cargo oil intankers, or during loading and delivery. Another large input is from bilge waters and fuel oil,and steps have been taken to successfully, and substantially reduce this. Ballast water isrequired once a ship has unloaded its cargo, and seawater is pumped in to do this. Whenthe ballast is discharged back into the sea, it takes with it residual oil from the tanks. It isbecoming more common for tanks to be cleaned before ballast water is put in, thereforereducing the amount of oil entering the sea (IMO, 2002b).

Tanker operations

Tanker accidents

Bilge and fuel oil

Dry docking

Scrapping of ships

Non-tanker accidents

Atmospheric emissions

Coastal refineries

Offshore production

Marine terminals

Municipal wastes

Industrial wastes

Urban run-off

River run-off

Atmospheric fallout

Ocean dumping

Figure 3. Sea based sources of oil into the sea (source Clarke, 1997).

What happens when oil is spilled in the sea?

Oil is lighter than water, so if it is spilled in the sea it forms a thin slick on the surface. The

thickness of the slick and the speed at which it spreads is dependant on the sea temperatureand the nature of the oil (Clark, 1997). The composition of oil starts changing as soon as it isspilled. The light fractions evaporate, water soluble fractions dissolve and small drops of oilcan be suspended in the water column (emulsification). Water can also become emulsified inoil producing a brown low-density mass, often referred to as chocolate mousse.

Impacts of oil pollution

Birds

Almost every type of seabird has been found at some time covered in oil, including puffins,razorbills and guillemots. When a bird encounters an oil slick, its feathers become covered in


8/22



oil and its natural waterproofing is lost (Figure 4). The bird becomes waterlogged and usesvast amounts of energy to keep afloat. The feathers that provide insulation also becomedamaged so the bird gets very cold. The oiled bird becomes very ill through attempts toclean its plumage and ingesting the poisonous oil. Finally, because the bird is so busy tryingto stay afloat, keep warm and clean oil off itself, it has no time to feed. So if it does not drown,freeze, or get poisoned, it will probably starve (RSPB, 2003).

Figure 4. Dead, oiled gannet. Image: Keith Hiscock.

Cetaceans whales, dolphins and porpoises

Cetaceans may be able to avoid oil slicks but they may suffer from a decrease in availableprey (Brina & Pollard, 1999). They may inhale toxic oil vapour when they surface to breathe,damaging the airway and lungs. A dolphins eyesight may also be affected by oil (GMOPIG,2003b).

Seals

Seals come into contact with oil spills in two ways. Firstly, they spend a lot of the time at thesurface, as they need to breathe. Secondly, they frequently haul themselves out of the water

onto beaches that may also be covered in oil (Figure 5). Atlantic grey seals are particularlyvulnerable during the pupping season as pups remain ashore for several weeks. Theingestion of oiled food or the inhalation of oil droplets and vapours will attack exposedsensitive tissues. These include mucous membranes that surround the eyes and line themouth, throat and the respiratory surfaces. This can cause corneal abrasions, conjunctivitisand ulcers. Eating prey contaminated with oil could lead to the build-up of hydrocarbons intissues and organs (GMOPIG, 2003b).

Otters

Unlike seals, otters depend on their fur for insulation. If they are exposed to oil, this insulatingproperty is lost. During grooming the otter may inhale or ingest oil that can damage lungs,cause ulcers and result in liver and kidney damage (GMOPIG, 2003b).

Shellfish

Animals such as adult mussels are filter-feeding organisms. Oil can coat their feedingapparatus and gills eventually killing them (Brina & Pollard, 1999). For impacts on seabedspecies refer to the MarLINmatrix (http://www.marlin.ac.uk/baski/activity_factor.asp)


9/22



Figure 5. An oiled seal pup at Skomer during the Christos Betosspill on 19 October 1978. A fewhours later the seal was dead. Image: Keith Hiscock

Plants

Plants can be smothered by heavy fractions of oil that sink to the seabed, or coat seashores

(Brina & Pollard, 1999).Fish

Fish eggs may not hatch and young fish may die if they are exposed to oil. Adult fish canswim away from areas that are contaminated. However, if the oil is dispersed in the watercolumn, it may be taken up through their gills or eaten resulting in an accumulation in thestomach, gall bladder and liver (Environment Canada, 2003a). In commercial species thismay lead to the flesh having a tainted flavour making it inedible (Clark, 1997).

People

In the event of an oil spill, harbours marinas and tourist beaches are often closed. Fishingmay be temporarily stopped resulting in lost income for commercial fisheries. Oil can coatboats and fishing gear and extensive cleaning may be required. People fear that fish may betainted, resulting in a loss of income for fishermen and other local enterprises.

Rocky shore species

Rocky shores are a high energy environment. As waves crash against the shore, they washaway oil which may have been deposited following a spill. This reduces the amount of timethe oil is on rocky shores. Fresh oil contains toxic chemicals which are dangerous toanimals, so if oil arrives onshore soon after spillage, it will cause much more damage. Allanimals on the shore are vulnerable to the toxins of the oil. After a few days at sea, the oilloses these toxic properties. Old oil arriving on shore presents physical problems such assmothering. Filter feeding animals are particularly at risk. It takes around seven years forrocky shores to recover from oil spills (Figure 6).

Sandy shore species

The action of sand on sediment shores depends on the size of the sediments. On coarsersediments, oil will seep between the particles and become difficult to remove and slow tobiodegrade. On fine sediments, the oil cannot penetrate and will form a layer on thesediment. In this situation, the toxicity of the oil is slow to leach out and causes a longer termproblem. Organisms living in the upper layers of the sediment will be smothered as soon asthe oil settles. Many of these species are filter feeders or detritivores, which will be preventedfrom feeding by the presence of the oil. The recovery of populations can be slowed by thecontinued presence of toxins.


10/22


11/22



steam or dispersants can be used to clean rocks and harbour walls. Oil on rocky shores thathave boulders and stones of various sizes can be washed to the water line, for later recovery,by trickling water over it for a few days. Pebble or sand beaches are hard to clean, andphysical removal of the surface layers either by hand or bulldozer is required. Beachcleaning produces a large volume of oil-contaminated debris that is currently disposed of atrubbish dumps, but this is not a very satisfactory solution (Clark, 1997).

Control Measures

The International Convention for the Prevention of Pollution from Ships (MARPOL 73/78)Annex 1 prohibits deliberate discharges from ships of waste oils. The discharge of oil withinspecial areas is also prohibited and requires the provision of oil reception facilities at all ports.In 2001, northwest European waters were made a 'special area'. This area includes the NorthSea and its approaches, the Irish Sea and its approaches, the Celtic Sea, the EnglishChannel and its approaches, and part of the North Sea Atlantic, immediately to the west ofIreland.

The Merchant Shipping (Oil Pollution Preparedness, Response and Co-operationConvention) (Amendment) Regulations 2001, provide a framework for international co-

operation in dealing with major oil pollution incidents. It requires participants to establish anational contingency plan for handling marine pollution from shipping and offshoreinstallations (HMSO, 2001; Brina & Pollard, 1999).

The Merchant Shipping (Prevention of Oil Pollution) Regulations 1996 require that an oilrecord book is kept to log all discharges of oil to sea, to other ships or to shore basedreception facilities (Brina & Pollard, 1999; HMSO, 1996)

What can you do?

Report any oil slick at sea, or oil washing up on the coast to the Maritime and CoastguardAgency on 02380 3291000 including details of location and scale of the oil pollution

If you see any animals covered in oil contact the RSPCA 0870 5555 999 or in Scotland theSSPCA 0870 737 7722

If you see oil in any waterways contact the Pollution hotline on 0800 807060 (24 hours)

REFERENCES

Brina, G., & Pollard, S., 1999. Marine Conservation in the UK Action Guide. Ross-on-Wye:Marine Conservation Society.

Clark, R. B., 1997. Marine Pollution(4th Edn). Oxford: Clarendon Press.

Environment Canada, 2003a. Oil, Water and Chocolate Mousse - What About the Wildlifeand Fish? [on-line]. Ontario: EE publications cited [23/10/03]. Available from

Environment Canada, 2003b. Oil, Water and Chocolate Mousse - Chapter 5: Response [on-line].Ontario: EE publications cited [23/10/03]. Available from: http://www.ec.gc.ca/ee-ue/pub/chocolate/chpt5_e.asp

GESAMP (IMO/FAO/UNESCO-IOC/WMO/WHO/IAEA/UN/UNEP Joint Group of Experts onthe Scientific Aspects of Marine Environmental Protection). 2000. Report of the ThirtiethSession, Principality of Monaco, 2226 May 2000. Rep. Stud. GESAMP No. 69, 68 pp.[13/07/05] Available from


12/22



Global Marine Oil Pollution Information Gateway (GMOPIG), 2003a. Frequently askedquestions [on-line]. Stockholm: Global Marine Oil Pollution Information Gateway cited[23/10/03] Available from:

Global Marine Oil Pollution Information Gateway (GMOPIG), 2003b.Effects of oil on marinewildlife (species) [on-line]. Stockholm: Global Marine Oil Pollution Information Gatewaycited [20/10/03] Available from:

Her Majestys Stationery Office (HMSO), 2001. Statutory Instrument 2001 No. 1639 TheMerchant Shipping (Oil Pollution Preparedness, Response and Co-operation Convention)(Amendment) Regulations 2001 [on-line]. London: Her Majestys Stationery Office [cited21/10/03]- Available from: http://www.legislation.hmso.gov.uk/si/si2001/20011639.htm>

Her Majestys Stationery Office (HMSO), 1996. Statutory Instrument 1996 No. 2154 TheMerchant Shipping (Prevention of Oil Pollution) Regulations 1996 [on-line].London: HerMajestys Stationery Office [cited 21/10/03].Available from:

International Maritime Organisation (IMO), 2002a. IMOs 50th anniversary a record ofsuccess [on-line]. Geneva: International Maritime Organisation [cited 10/10/03].

Available from:

International Maritime Organisation (IMO), 2002b. Crude Oil Washing [on-line]. Geneva:International Maritime Organisation [cited 21/10/03].Available from:

Marine Conservation Society (MCS), 2002. Marine world oil pollution. Ross-on-Wye:Marine Conservation Society [cited 10/10/03]. Available from:

Royal Society for the Protection of Birds (RSPB), 2003. SOS save our seabirds [on-line].Sandy: Royal Society for the Protection of Birds:[cited 10/10/03].Available from:http://www.rspb.org.uk

Southward, A.J., 1979. Cyclic fluctuations in population density during eleven yearsrecolonisation of rocky shores in west Cornwall following the "Torrey Canyon" oil-spill in1967. In: Cyclic phenomena in marine plants and animals, Proceedings of the 13thEuropean Marine Biology symposium, Isle of Man, 27 September - 4 October 1978, (ed. E.Naylor & R.G. Hartnoll) pp.85-92. Oxford: Pergamon Press.

LINKS

Dept for Environment Food and RuralAffairs

http://www.Defra.gov.uk


Environmental Action Fund (Defra) http://www.defra.gov.uk/



Global Ballast Management Programme http://globallast.imo.org/index.asp

Global Marine Oil Pollution InformationGateway

http://oils.gpa.unep.org

International Maritime Organisation http://www.imo.org




13/22



United Kingdom Offshore OperatorsAssociation

http://www.ukooa.org.uk


14/22



CHEMICAL POLLUTION

Inputs of chemicals to the sea

There are approximately 60,000 organic pollutants in the marine environment. They enterthe marine environment via many sources including disposal of industrial effluents and waste,

run-off from agriculture land and urban areas and marine traffic (CEFAS, 2003).Land based sources

Current farming practices use lots of chemicals to prevent crop and livestock damage bypests and weeds. Runoff of pesticides and herbicides into surrounding rivers and streamswill eventually lead to the marine environment. Discharges from factories and chemicalproduction industries also add to chemical pollution.

Sea based sources

Chemicals are used when drilling for oil and gas. They are needed to lubricate drills, preventpipelines and machinery from corrosion, to stop unwanted growth of marine organisms and toseparate oil from water (UKOOA, 1998). Ships hulls are painted with antifoulants that stop

the growth of marine organisms. The weight and drag of the ship is increased if the hullbecomes covered with marine organisms and therefore more fuel is used to maintain thesame speed. In the early days of shipping compounds containing lime, arsenic, and mercurywere used as antifoulants. In the 1960s more effective chemicals were produced, usingmetallic compounds such as tributyltin (TBT); now banned for use on small boats.

Properties of chemicals

Many chemicals are toxic to marine life. Some chemicals are termed acutely toxic and killorganisms after a very short amount of time (Lincoln et al., 1998). Long term exposure tochronically toxic chemicals can interfere with the reproductive, developmental and immunesystems of an organism (Brina & Pollard, 1999).

A variety of chemicals do not break down easily in seawater and persist in the marineenvironment, or marine organisms. The risk of exposure to these chemicals is thereforeincreased (Brina & Pollard, 1999)

Synthetic chemicals that are fat-soluble, e.g. some pesticides such as DDT, organochloridesand polychlorinated biphenyls (PCBs), can build up in fatty tissues of marine species andconcentrate up the food web (Figure 8).

Effects on wildlife

Some chemicals that enter the environment disrupt the normal hormonal system of animalspecies. Such chemicals are termed endocrine disrupters. Endocrine disrupters, includingatrazine, bisphenol A, DDT, and TBT, can mimic or block natural hormones or interfere with

their production or metabolism (Linley-Adams, 1998).Cetaceans

Whales, dolphins and porpoises are at the top of the food chain and are therefore aresusceptible to pollution through food that has been contaminated with chemicals. Theanimals can become more liable to infection and their reproduction may be impaired (WWF-UK, 2004)


15/22



Effluent entering waterways contains very lowlevels of dangerous compounds.

Phytoplankton present in these waters will havelow contaminant levels of 0.025ppm.

Phytoplankton are grazed by zooplankton

increasing the level to 0.123ppm

Sand eels feed on zooplankton whichaccumulate contaminates to around 1.04ppm

Sand eels are consumed by large fish such as

cod, which accumulate contaminants to around4.83ppm.

Eggs of birds such as the herring gull, whichare scavengers and will encounter large fishspecies such as cod, have the highest levels ofcontaminants 124ppm. This is a 5000 foldincrease in the concentration of contaminants inphytoplankton.

Figure 8. Diagram of bioaccumulation along a simple marine food chain. Contaminant values fromhttp://www.epa.gov/glnpo/atlas/images/chart403.gif

Fish

Experimental studies have shown that endocrine disrupters affect both freshwater andmarine fish. Male flounder in the Tyne, Mersey and Solway estuaries were found to havesigns of feminisation, including egg-producing cells in testis, reduced testis growth rates andsize, female reproductive tracts and increased levels of vitellogenin (egg protein) (Linley-Adams, 1998).

Molluscs

The effects of TBT on dog whelks (Nucella lapillus) have been studied extensively andrepresent one of the best known examples of chemical pollution endocrine disruption.Female dog whelks grew a penis and sperm duct and were unable to reproduce resulting in asevere decline in population numbers (Brina & Pollard, 1999).


16/22



Seals

In the Wadden Sea (east coast of the North Sea) seals are having fewer pups and thepopulation is declining. In this area, the seals eat herring which has been contaminated withPCBs, and have half the breeding success of seal populations that eat North Atlantic herring.PCBs are known to stimulate production of enzymes which break down female hormonescausing miscarriages (WWF-UK, 2003).

Contaminants, especially in enclosed waters have most likely had a much greater adverseeffect on marine biodiversity or abundance that most measures indicate. For instance,although TBT expressed itself through dog whelks and oysters, the number of species in theupper Crouch estuary doubled after it was banned (Rees et al., 1999, 2001).

Control Measures

EU Directive 96/61/EE Integrated Pollution Prevention Control directive (IPPC)

Sustainable production and use of chemicals a UK strategy for hazardous substances,DETR, 1999.

OSPAR - Regulations governing the carriage of chemicals by ship are contained in the

International Convention for the Safety of Life at Sea (SOLAS) and the InternationalConvention for the Prevention of Marine Pollution from Ships, as modified by the Protocol of1978 relating thereto (MARPOL 73/78).

REFERENCES

Brina, G., & Pollard, S., 1999. Marine Conservation in the UK Action Guide. Ross-on-Wye:Marine Conservation Society:

Brown, V, 2003. Causes for concern: chemicals and wildlife [on-line]. Brussels: WWF [cited15/04/04]. Available from: .

Centre for Environment, Fisheries and Aquaculture Science (CEFAS), 2003. Endocrine

disrupters and European Marine Sites in England [on-line]. Lowerstoft: CEFAS [cited12/01/04]. Available from:

Lincoln, R., Boxshall, G. & Clark, P., 1998. A dictionary of ecology, evolution andsystematics(2nd edition). Cambridge: University Press.

Matthiessen, P., & Law, R. J., 2002. Contaminants and their effects on estuarine and coastalorganisms in the United Kingdom in the late twentieth century. Environmental Pollution,120, 739-757.

Rees, H.L., Waldock, R., Matthiessen, P. & Pendle, M.A., 1999. Surveys of the epibenthos ofthe Crouch Estuary (UK) in relation to TBT contamination. Journal of the Marine BiologicalAssociation of the United Kingdom, 79, 209-223.

Rees, H.L., Waldock, R., Matthiessen, P. & Pendle, M.A., 2001. Improvements in theepifauna of the Crouch estuary (United Kingdom) following a decline in TBTconcentrations. Marine Pollution Bulletin, 42, 137-144.

United Kingdom Offshore Operators Association (UKOOA), 1998. Chemical Discharges tothe Marine Environment [on-line]. Aberdeen: UKOOA cited [07/01/04].Available from:

WWF-UK, 2004. Dolphins [on-line]. Goldalming: WWF-UK [cited 15/04/03]. Available from:

WWF-UK, 2003. Chemicals and health in wildlife [on-line]. Godalming: WWF-UK [cited18/03/04]. Available from:


17/22



LINKS

Centre for Environment, Fisheries andAquaculture Science (CEFAS)

http://www.cefas.co.uk

Dept for Environment Food and Rural Affairs http://www.Defra.gov.uk


Environmental Action Fund (Defra) http://www.defra.gov.uk/environment/eaf/


Environment & Heritage Service NorthernIreland

http://www.ehsni.gov.uk

Greenpeace http://www.greenpeace.org.uk

International Maritime Organisation http://www.imo.org


Scottish Environmental Protection Agency http://www.sepa.org.ukUnited Kingdom Offshore Operators Association http://www.ukooa.org.uk

UNEP/GPA Persistent Organic Pollutants http://www.gpa.unep.org/pollute/organic.htm

Whale and Dolphin Conservation Society http://www.wdcs.org

WWF-UK http://www.wwf.org.uk


18/22



NOISE POLLUTION

History

The amount of noise in the ocean has steadily increased through the twentieth century ANDinto the twenty-first. Sources of underwater noise caused by humans include, oil rigs,

shipping (e.g. tankers and cargo vessels), seismic exploration, fishing vessels and militaryactivities (EIA, 2001).

Importance

There is little known about the effects of underwater sound on marine invertebrates (Vella etal., 2001) so they will not be covered in this topic page.

It is generally agreed that hearing plays a large part in the lives of whales and dolphins. Themajority of marine mammals rely on sound as they hunt for food, avoid predators and find amate. Sound of the same frequency used by whales and dolphins (cetaceans) may have adetrimental effect on them (NRDC, 1999).

Sources of underwater noiseNatural

There are many natural sources of noise underwater, at low frequencies events such asearthquakes and volcanoes produce significant amounts of noise. On the surface, breakingwaves, air bubbles and spray or rain hitting the water can generate large amounts of noise.Shrimps snapping create a sizzling noise over rocky areas in both temperate and tropicalwaters. Seals and cetaceans are very vocal and can emit powerful sounds. Fish also makea contribution to the background noise in the oceans (Gordon & Moscrop, 1996).

Shipping

Noise from ships comes from their propellers, from machinery and from the movement of the

hull through the water. Different types of ship produce different amounts of noise. Generallylarger ones are noisier than smaller ones and older, less maintained vessels are louder thannewer ones. It is thought that larger ships, which emit lower frequency noises, are within therange of hearing for baleen whales (including blue whale, minke whale, sei whale, northernright whale and humpback whale). Higher frequency sounds emitted by high-speed vesselsare more likely to affect dolphins and porpoises (Gordon & Moscrop, 1996).

Seismic exploration

Seismic surveys are carried out to build up a picture of the rock formations underneath theseabed. During a survey pulses of low frequency sound are released at regular intervals,these pulses pass through the water and seabed deep into the earth. The reflected echoesare recorded and analysed and the results are used to create a computer-generated image of

the geology far below the seabed (UKOOA, 2002).Offshore oil production

During oil production noise is produced by drilling, increased vehicle traffic, pipeline layingand seismic site surveys. During decommissioning of a rig, explosives may be used(Hammond et al., 2003).

Dredging

The noise produced by dredging depends on the characteristics of the dredger. Noise fromdredging can often be constant within a restricted area for days or weeks at a time. (Gordon& Moscrop, 1996).


19/22



Acoustic thermography

The speed of sound in water is determined by the temperature, therefore, measuring thespeed of sound through the sea can be used to measure water temperature. By measuringthe time it takes sound to travel across ocean basins the average temperature of the oceancan be measured.

SonarDepth sounders emit a high frequency beam towards the seabed and are fitted on mostvessels. Sonar used to find fish and for charting purposes is lower frequency. Powerfulsonars fill large volumes of the ocean with noise and so may have an effect over large areas(Gordon & Moscrop, 1996).

Military

Undersea warfare is highly dependent on acoustics, but the details of the equipment used isclassified. However, it is thought that military sources have a substantial input of noise to themarine environment (Simmonds et al., 2003).

Problems

Physical(Simmonds & Dolman, 1999)

Auditory

Damage to ears

Permanent hearing loss

Temporary hearing loss

Non Auditory

Damage to body tissues

The bends

Recent studies have suggested that noise may be a factor in major stranding incidents.Fourteen beaked whales were found stranded in the Canary Islands just 4 hours after anexercise using underwater military equipment was started. Bubbles were found in the tissuesand blood and it is thought that the whales were suffering from decompression illness knownby divers as the bends. It is unclear whether the sound waves caused the bubbles to beformed in the tissues or if a faster than normal ascent (to get away from the noise) wasresponsible (Jepson et al., 2003).

Perceptual

Stopping communication between animals of the same species

Masking biologically important noises

Interfering with the ability to acoustically interpret surrounding environment

Shifting range of vocalisations which can take a lot of energy

Masking important biological sounds such as sounds from prey, courtship sounds and thecommunication between calves and mothers, is likely to prevent animals from feeding, makethem more vulnerable to attack by predators, unable to socialise, reproduce or rear theiryoung properly (Simmonds, et al., 2003).

Behavioural(Simmonds & Dolman, 1999)

Interruption of normal behaviour


20/22



Modified behaviour

Displacement behaviour

Responses of whales and dolphins to noise pollution can be very subtle such as a change inbreathing rate, surfacing activity or dive time and changing direction or moving away from thesource of the noise (Gordon & Moscrop, 1996). Long-term effects have not been extensively

studied but may include the exclusion of animals from areas that are biologically important tothem, for example breeding, feeding or resting grounds (WDCS, 2003).

Chronic/stress

Reduced viability

Increased risk of disease

Sensitisation to noise

Habituation to noise

An animal may avoid an area where a particular source of noise is if it has been exposed to apainful level of noise causing sensitisation (Simmonds & Dolman, 1999). Animals may

become used to a noise even though it is damaging (habituation). Weilgart (1997) noted thatin the short-term it is very difficult to detect damage from sound in the marine environmentand that gradual deafness may be misinterpreted as a growing tolerance to noise.

Indirect effects(Simmonds & Dolman, 1999)

Decrease prey availability

Increased vulnerability

There may be indirect effects of noise on cetaceans. Seismic surveying has been shown toaffect fish distribution (Engas et al., 1996) and abundance. This in turn will affect the feedingof cetaceans (WDCS, 2003).

Control Measures

Under the EU Habitats Directive 92/43/EEC Article 12, member states are required toestablish a system of strict protection for the animal species listed in Annex IV, whichincludes all cetaceans. The Offshore Petroleum Activities (Conservation of Habitats)Regulations 2001 implements the EU Habitats Directive for all oil and gas activities within theUK Coastal Shelf. As part of these regulations, any company wishing to carry out a seismicsurvey must apply for consent from the Department of Trade and Industry (DTI). The JointNature Conservation Committee (JNCC) are consulted on whether consent should begranted for each individual seismic survey. If consent is granted, a standard condition is thatthe JNCC Guidelines for minimising acoustic disturbance to marine mammals from seismicsurveysare always followed. Another condition of a consent being granted to carry out a

seismic survey is that a report is submitted to the JNCC for each individual survey. Thisshould detail how the JNCC Guidelines were implemented, the marine mammals sighted, themethods used to detect them and any problems encountered. (JNCC, 1998, 2003).

Environmental Protection Act 1990 includes a provision for the control of noise as anuisance. The Wildlife and Countryside Act 1981 has reference to disturbance. This couldbe interpreted to protect wildlife from noise pollution (Brina & Pollard, 1999).

REFERENCES

Brina, G., & Pollard, S., 1999. Marine Conservation in the UK Action Guide. Ross-on-Wye:Marine Conservation Society:


21/22


22/22


Weilgart, 1997. Cited in Simmonds, M, Dolman, S, Weilgart, L. (eds.), 2003. Oceans ofNoise [on-line]. Chippenham: Whale and Dolphin Conservation Society [cited 31/10/03].Available from:

Whale and Dolphin Conservation Society (WDCS), 2003. The impacts of noise on cetaceans[on-line]. Chippenham: Whale and Dolphin Conservation Society [cited 28/10/03].Available from:

LINKS

Dept for Environment Food and RuralAffairs

http://www.Defra.gov.uk

Dept of Environment in Northern Ireland Http://www.doeni.gov.uk

Environmental Action Fund (Defra) http://www.defra.gov.uk/environment/eaf/



Joint Nature Conservation Committee http://www.jncc.gov.uk



Seawatch Foundation http://www.seawatchfoundation.org.uk

Whale and Dolphin Conservation Society http://www.wdcs.org

CITATION

Ager, O. & Jefferson, R., 2005. Marine Life Topic Note. Marine Pollution. Marine LifeInformation Network[on-line]. Plymouth: Marine Biological Association of the UnitedKingdom. Available from:

Funded by the Environmental Action Fund of Defra

Date post:	10-Apr-2018
Category:	Documents
Upload:	sai-prasad
View:	217 times
Download:	0 times

MLTN Pollution

Documents