Oil Spill & Oil Pollution

Oil Spill & Oil Pollution

Chemistry, Ecotoxicology, Impact On Biodiversity & Ecosystems & Management

Image source: https://response.restoration.noaa.gov/training-and-education/educationstudents-and-teachers/how-do-spills-happen.html

Golam Kibria; 21 November 2018 Citation: Kibria, G. 2018. Presentation- Oil Spill & Oil Pollution- Chemistry, Ecotoxicology, Impact On Biodiversity & Ecosystems & Management. 114p. DOI: 10.13140/RG.2.2.14293.06885 https://www.researchgate.net/publication/329074954_Presentation_Oil_Spill_Oil_Pollution_Chemistry_Ecotoxicology_Impact_On_Biodiversity_Ecosystems_Management

GolamKibria_Oil spill_oil pollution_DOI: 10.13140/RG.2.2.14293.06886 21 Nov18

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Abstract The oil spill is a form of pollution and an environmental disaster and can happen accidentally (blow out, natural disaster), ships/tankers collisions/operational accidents; drilling rigs & wells accidents; and transport (road and rail) accidents etc. This presentation provides an overview of oil spill/oil pollution in the context of i) chemistry & ecotoxicology; ii) impacts on biodiversity and ecosystems (fish, plankton, seagrasses, corals, mangroves) and iii) management of oil spill/oil pollution

Summary i. Oil spill/oil pollution (chemistry & ecotoxicology) The oil spill is the release of liquid petroleum hydrocarbons, especially in the marine ecosystem. The spill can be crude oil or oil refined products like gasoline (petrol), diesel fuels, jet fuels, and kerosene. Crude oils are mixtures of hydrocarbon compounds (saturates -alkanes); aromatics (BTEX, PAHs); polar-high molecular weight polyaromatics (containing sulfur, nitrogen, or oxygen). The composition oil fraction includes 74% saturated hydrocarbons, 16% aromatic hydrocarbons, 10% polar hydrocarbons. Oils are classified into a) gasoline-like products-very light crude oils-API: >45; b) diesel like products/light crude oils-API: 35-45; c) medium crude oils-API: 17.5-35; and d) heavy crude oils API: 10-17.5) (API) [API=the American Petroleum Institute gravity scale; BTEX=benzene, toluene, ethylbenzene, xylene; PAH=Polycyclic aromatic hydrocarbons]. The oil spill is a form of pollution and an environmental disaster and can happen accidentally (blow out, natural disaster), ships/tankers collisions/operational accidents; drilling rigs & wells accidents; and transport (road and rail) accidents etc. The BTEX compounds are found naturally in crude oil, coal and gas. BTEX compound such as benzene is a known carcinogen (cancer-causing) whereas, toluene, ethylbenzene and xylenes are not recognized as carcinogenic. PAHs include acenaphthene, anthracene, naphthalene, phenanthrene, benzo[a]pyrene are often a result of environmental pollution by oil and oil spills. PAHs are non-polar and lipophilic. Larger PAHs are insoluble in water, whereas smaller PAHs (2 or 3 rings) are soluble & can contaminate drinking water. PAHs exposure can cause cancer, cardiovascular disease and poor fetal development. According to US Agency for Toxic Substances & Disease Registry (ATSRD), benzene (listed at 6), benzo(A)pyrene, PAH, benzofluoranthene (listed at 8,9,10 respectively) are harmful to human health and the environment. Log kow (hydrophobicity of chemicals) of the PAHs ranged from 3.37 to 8.0 [e.g. naphthalene 3.37; benzo(e)pyrene 6.04; chrysenes 8.0] and acute toxicity values (LC50) of PAHs ranged from 0.06 µg/L to 4870 µg/L [e.g. naphthalene 4870 µg/L; benzo(e)pyrene 7.6; chrysenes 0.06]. Crude oils are naturally occurring unrefined petroleum products. Crude oils are formed from the remains of plants and animals (zooplankton & algae) which died millions of years ago (“Fossil fuels”). Crude oils are made up of hydrogen and carbon atoms (HC compounds) (about 82 to 87% carbons by weight and 12 to 15% hydrogen by weight). Crude oils are refined to produce gasoline/petrol, diesel and various forms of petrochemicals. Asphaltenes are among the largest and heaviest components in a crude oil; high asphaltene oils are very susceptible to creating water-in-oil emulsions or chocolate mousses. As soon as the oil is spilled, its chemical & physical properties begin to change through a process known as weathering. It includes spreading, evaporation, dispersion, dissolution, biodegradation, photooxidation, emulsification, sedimentation. Oils are lighter than water, therefore, they float; lighter oils are very volatile, flammable, low viscous, spread & evaporate rapidly but highly acute toxicity to animals and plants. Heavy oils are more viscous than light oils low acute toxicity to biota but can cause long-term effects on biota and ecosystems via smothering or coating (birds), they likely sink, or remains as residues on or in sediments. Lighter oil is unlikely coat surfaces of animals but can be taken up by diffusion across gills by larger organisms (fish) or across the cutaneous/skin layer in smaller organisms (plankton). The Deep-water Horizon spill (the Gulf of Mexico, 10 April – 14 July 2010); and Exxon Valdez spill (23 March 1989, Alaska, USA) caused the most significant impact on biodiversity and ecosystems. During the Deepwater Horizon Oil spill (2010), the most abundant petroleum hydrocarbons detected were benzene, toluene, ethylbenzene, and total xylenes at concentrations up to78 μg/L. ii. Oil spill/oil pollution-impacts on biodiversity and ecosystems (fish, plankton, seagrasses, corals, mangroves) Oil exposure to fish caused edema (fluid accumulation), cardiac toxicity, tissue death, and abnormal development; phytoplankton and zooplankton accumulate oils rapidly via diffusion; oil can kill fish food (zooplankton) and can be accumulated in the food chain (algae-zooplankton-invertebrates-fish-birds) and can be transferred to humans via the food chain. Corals exposed to oil showed mortality, decreased growth rates, decreased lipid content, decreased survival of larvae, decreased gonadal development and increased bleaching. Seagrasses are sensitive to oil exposure leading to decreased growth rates, smothering (suffocating) of leaves, changes in the chlorophyll content of leaves and reduced photosynthetic ability. Mangrove plants may die from suffocation (reduced O2 flow), starvation, yellowing (chlorosis), increases rates of defoliation, reduced pneumatophores, reduced photosynthetic efficiency and other physiological/toxicological impact; oil physically can cover mangrove plants, their roots (pneumatophores); oil can kill mangrove plants within a few weeks to several months iii. Oil spill/oil pollution-management To reduce oil spill impacts the following techniques/methods can be applied a) booms and skimmers (to contain oil); b) dispersant (formation of smaller droplets & disperse by wind, wave and currents); c) offshore burning (to remove the large quantity of oil quickly); d) natural recovery (slow degradation, natural removal by waves, currents); e) manual oil removals (hand tools and manual labour); f) sorbents (peat, wood, cotton, straw, corncob, shredded sugarcane); g) vacuuming (to remove pooled oil or thick oil) and h) biodegradation by microorganisms. GolamKibria_Oil spill_oil pollution_DOI: 10.13140/RG.2.2.14293.06886 21 Nov18

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1. Chemistry & Ecotoxicology of Oil


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What is An Oil Spill? • the release of a liquid petroleum hydrocarbons This especially in the marine ecosystem

• a form of pollution • spill of crude oil/distilled products

presentation is mainly Focused on marine oil spill/marine oil pollution

• gasoline/petrol; diesel fuels; jet fuels; kerosene sto-dd-ard solvent (pain thinner-Spirit/white spirit) hydraulic oils; lubricating oils GolamKibria_Oil spill_oil pollution_DOI: 10.13140/RG.2.2.14293.06886 21 Nov18

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Causes of Oil Spill Oil spill is an environmental disaster Accidentally oil spill (blow outs, natural disasters) e.g. Deep-water Horizon spill, the Gulf of Mexico, 10 April - 10 July 14, 2010; Exxon Valdez spill, 23 March, 1989, Alaska, USA)

Ships/tankers collisions/operational accidents Spill of refined petroleum products (gasoline)

A blowout is the uncontrolled release of crude oil and/or natural gas from an oil well or gas well after pressure control systems have failed.

Spill of heavier fuels used by large ships bunker fuel

The Gulf War oil spill was one of Intentional oil spill (jet to avoid any major the largest oil disaster, Iraq War 1991) spills in history, resulting from Natural seeps- production sites/drilling sites/refineries the Gulf War in Drilling rigs & wells accidents 1991 Storage sites leakage of containers spilled ranged around Transportation: Road and rail accidents 11,000,000 US Pipeline failures (Baker 1985; Tewari and Sirvaiya, 2015) barrels 5 GolamKibria_Oil spill_oil pollution_DOI: 10.13140/RG.2.2.14293.06886 21 Nov18

Distribution of Global Oil Reserves in 2017

https://www.statista.com/statistics/237065/share-of-oil-reserves-of-the-leading-ten-countries/


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Commercial Crude Oil Supertanker AbQaiq The commercial oil tanker AbQaiq • up to 550,000 Deadweight tonnage (DWT); • Ultra Large Crude Carrier

https://en.wikipedia.org/wiki/Oil_tanker

Supertankers move large quantities of unrefined crude oil from its point of extraction to refineries

GolamKibria_Oil spill_oil pollution_DOI: 10.13140/RG.2.2.14293.06886 21 Nov18 Image source: https://commons.wikimedia.org/wiki/File:Oil_tanker_Abqaiq_in_2003.jpg

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An Oil Tanker Taking on Fuel, or “Bunkering

Bunker receiving ship

Bunker tanks:separate storage tanks for consumption in ship’s machinery.

Bunker supply ship


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Deep-Water Horizon Spill, 2010 The Deepwater Horizon oil spill released up to 627,000 tonnes of oil following the blowout Deepwater Horizon drilling rig prior to the incident.

Anchor handling tugs and platform supply vessels combat the fire on the Deepwater Horizon while the U.S. Coast Guard searches for missing crew.

Controlled burning of oil

spilled in the Deepwater Horizon disaster, Gulf of Mexico, May 6, 2010. The burning oil was contained by a length of boom

The Deepwater Horizon event led to an unprecedented discharge

of ∼4.1 million barrels of oil to the Gulf ofMexico Emulsified oil from the 2010 Deepwater Horizon/BP spill remains

Reddish-brown “chocolate mousse” formed

on, and pooled below, vegetation in Pass a Loutre, La., following a previous week's storm. Image shot on May 22, 2010. (NOAA)

Wildlife mortality


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Crude Oils (Unrefined Oils) (Fingas, 2018, page 2)

Crude oils (USA, Saudi Arabia, and Russia (leading producers of oil in the world). https://www.investopedia.com/terms/ c/crude-oil.asp

Residual fuel oil= heavy fuel oil; It is the remainder of the crude oil after gasoline and distillate fuel oils have been extracted through distillation. It fuels thermal power stations or robust

.

egines

Refining is the complex series of processes that manufactures finished petroleum products out of crude oil. While refining begins as simple distillation (by heating and separating) GolamKibria_Oil spill_oil pollution_DOI: 10.13140/RG.2.2.14293.06886 21 Nov18

Crude oils naturally occurring unrefined petroleum products (fossil fuels) Fossil fuels-formed from the remains of plants and animals (zooplankton & algae) which died millions of years ago (“Fossil fuels”) Crude oil made up of hydrogen and carbon atoms (HC compounds)

Refinery yield From a barrel of crude oil (1 barrel-159 L

• 82 to 87% percent carbon by weight • 12 to 15 percent hydrogen by weight https://www.britannica.com/science/crude-oil)

Crude oil Refined to produce Gasoline/petrol, diesel and various forms https://www.ceoe.udel.edu/oils pill/crudeoil.html

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Crude Oil Compounds Compounds

Saturates (Alkanes) CnH2n+2

The lightest hydrocarbon found as a dissolved gas is methane (CH4), the main component of natural gas. Saturated means carbon atom are saturated with hydrogen

Aromatics (BTEX, PAH) • • •

volatile organic compounds (VOCs); Light aromatic HC “Aromatic=“ because these compounds has a

pleasant smell/ fragnant • • •

aromatics are cyclic but unsaturated hydrocarbons with alternating double bonds The simplest aromatic hydrocarbon is benzene (C6H6). heavy crude oils usually contain more aromatics than light crudes.

Polar (high-molecular-weight polyaromatics contain several heteroatoms such as S, N, O)

Characteristics

Structure

• Saturated hydrocarbons • Linear, branched or cyclic • Single bond Less toxic & Readily biodegrade • Unsaturated HC • One benzene ring of six carbons • Double bonds • Most toxic to marine life. • BTEX (benzene, toluene, ethylbenzene, xylene); PAH (Polycyclic aromatic

alternating double bonds

hydrocarbons)

• Aromatics with sulfur, nitrogen, oxygen in their structure 11 GolamKibria_Oil spill_oil pollution_DOI:

Essential Component of Petroleum

Saturated HC

Unsaturated HC

https://www.e-education.psu.edu/fsc432/node/5


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BTEX (benze, toluene, ethylbenzene and xylenes)

The BTEX compounds are found naturally in crude oil, coal and gas deposits • Benzene (C6H6) • Toluene (C7H6) • Ethylbenzene (C6H5CH2CH3) • Xylene (C8H10) https://www.aeroqual.com/what-is-btex https://en.wikipedia.org/wiki/BTX_(chemistry)

• Benzene is a known carcinogen (cancer causing). • Toluene, ethylbenzene and xylenes are not recognized as carcinogenic • The Australian Drinking Water Guidelines (ADWG) for benzene in drinking 1 part per billion (ppb) . 1 ppb is equivalent to 1 micro gram per litre, or a teaspoon of liquid in an Olympic size swimming pool GolamKibria_Oil https://www.ehp.qld.gov.au/management/non-mining/btex-chemicals.html; https://www.e-education.psu.edu/fsc432/content/aromatic-hydrocarbons

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BTEX Sources Natural sources Man made sources

Crude oil Sea water close to natural gas, petroleum deposits Volcanoes and forest fires • motor vehicles, aircrafts, and cigarette smoke • processing of refined petroleum products and c oal,(paints, thinners, rubber products, adhesives, inks, cosmetics and ph armaceutical products https://www.ehp.qld.gov.au/management/coal-seam-gas/pdf/btex-report.pdf; https://www.ehp.qld.gov.au/management/non-mining/btex-chemicals.html

Australian Aquatic ecosystems Protection

Australian Drinking water

GolamKibria_Oil spill_oil pollution_DOI: 10.13140/RG.2.2.14293.06886 21 Nov18 https://www.ehp.qld.gov.au/management/coal-seam-gas/pdf/btex-report.pdf

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Toxicity & Eco-oxicity of BTEX Compounds (based on MSDS) Benzene Class 1 human carcinogen 930 mg/kg

Toluene Non-carcinogenic

Xylenes Non-carcinogenic

5580 mg/kg

2119 mg/kg

LC50 (Fish)

Rainbow trout: 5.3 mg/L

Fish (Blue Gill ): 17 mg/L

3.77 mg/l (rainbow trout)

Log kow

2.13

2.7

3.1

(Hydrophobic compounds have a log kow>3)

http://www.sciencelab.com/msds.php?msdsId=9927 339; https://fscimage.fishersci.com/msds/02610.htm https://pubchem.ncbi.nlm.nih.gov/compound/benze ne#section=LogP

http://www.sciencelab.com/msds.php?msdsI d=9927301

http://www.sciencelab.com/msds.php?msdsI d=9927646

Carcinogenicity LD50 (Rat)

https://www.slideshare.net/emksu84/hydrophobic-vs-hydrophilic


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https://fscimage.fishersci.com/msds/02610.htm

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Polycyclic Aromatic Hydrocarbons

(PAH)

• PAHs include acenaphthene, anthracene, naphthalene, phenanthrene, benzo[a]pyrene and are often a result of environmental pollution by oil and oil spills (Nugegoda & Kibria, 2017) • multiple aromatic rings (2 rings, 3 rings, 5 or 6 rings)

https://www.e-education.psu.edu/fsc432/content/polyaromatic-and-hydroaromatic-compounds

• non-polar & lipophilic • Heavy crude oils contain more aromatics than light crudes. • larger PAHs insoluble in water, smaller PAHs (2 or 3 rings) are soluble & contaminates drinking water • PAHs exposure can cause cancer, cardiovascular disease and poor fetal development. GolamKibria_Oil spill_oil pollution_DOI: 10.13140/RG.2.2.14293.06886 21 Nov18

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Polycyclic Aromatic Hydrocarbons

Two rings

Three rings

Three rings

Four rings

https://www.e-education.psu.edu/fsc432/node/5 GolamKibria_Oil spill_oil pollution_DOI: 10.13140/RG.2.2.14293.06886 21 Nov18

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USEPA list of 16 Priority PAHs 2005)

Two rings

Three rings

Four rings

(Lima et al.

Cancer causing PAHs

Two rings

Three rings

Four rings

Four rings

Five rings

Five rings

Five rings Five rings

Six rings

Six rings


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Priority PAHs (based on ATSDR 2017 Substance Priority List) (out of 275 hazardous substances)

Agency for toxic substances & disease registry 6,8,9, 10, 15 are priority PAHs (based on their immediate threat to human health and the environment) https://www.atsdr.cdc.gov/spl/index.html


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USA EPA Priority List of PAH and Potential for Cancer (Lima et al. 2005; Rubailoa et al. 2008)


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PAHs Frequently Found in Crude & Refined Petroleum (Their Log Kow & Acute & Chronic Toxicity) (Neff et al. 2005, p27)

Solubility and toxicity values are micrograms per liter (μg/L ppb). PAHs are hydrophobic (have low solubility in water)


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Heteroatom HC Compounds (S,N,O) • In the oils the proportions of carbon, sulfur, nitrogen, and oxygen compounds are higher at the expense of hydrogen content • Heavier crude oils also contain organometallic compounds of commonly nickel and vanadium • Sulfur is the most important heteroatom found in crude oil and refinery products petroleum as H2S •

https://www.e-education.psu.edu/fsc432/node/5

S compounds found in crude oil

N compounds found in crude oil


O & metallic compounds found in crude oil

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Case Study: Composition and Fate of Gas and Oil Released to the Water column During the Deepwater Horizon Oil spill (Reddy et al. 2012) Reddy, et al. 2012. Composition and fate of gas and oil released to the water column during the Deepwater Horizon oil spill. www.pnas.org/cgi/doi/10.1073/pnas.1101242108 PNAS ∣ December 11, 2012 ∣ vol. 109 ∣ no. 50 ∣ 20229–20234

Reddy et al. 2012 collected distinct samples directly above the Macondo well (MW) on June 21, 2010, and analyzed the gas and oil. The most abundant petroleum hydrocarbons larger than C1-C5 were benzene, toluene, ethylbenzene, and total xylenes at concentrations up to 78 μg/L


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Case study: Composition and Fate of Gas and Oil Released to the Water column During the Deepwater Horizon Oil spill (Reddy et al. 2012) Reddy, et al. 2012. Composition and fate of gas and oil released to the water column during the Deepwater Horizon oil spill. www.pnas.org/cgi/doi/10.1073/pnas.1101242108 PNAS ∣ December 11, 2012 ∣ vol. 109 ∣ no. 50 ∣ 20229–20234

The composition of the MW-1 oil fraction contained • 74% saturated hydrocarbons • 16% aromatic hydrocarbons • 10% polar hydrocarbons


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Case study: Composition and Fate of Gas and Oil Released to the Water Column During the Deepwater Horizon Oil Spill (Reddy et al. 2012) Gas and Oil Samples Collected using Isobaric gas-tight (IGT) Samplers Deployed from a Remotely Operated Vehicle (ROV) Images of (A) IGT sampler and (B) schematic of system used to collect and separate the contents of the IGTs.

The IGT sampler, located in the center of the picture, is held by a robotic arm seen on the right side of the image


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Aromatic= Petroleum compounds with ringed structures


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Characteristics of Oil Specific gravity Specific gravity (SG) of Oils & Water • SG: Crude oils/refined petroleum < 1.0 g/ml (The density relative to that of water) • SG of Fresh water SG: 1.0 g/ml; SG of Sea water 1.025 g/mL; Oils are lighter than water, therefore, float (weight of a substance (oil)/to the weight of water)

(Hook et al.,

2016)

API (The American Petroleum Institute) gravity scale (oils

API gravity scale for oils (four groups) • Group 1: light oils (API > 45o)

grouped) °API = (141.5/specific gravity) – 131.5

• Group 4: heavy oils (API 3) and some are highly toxic to aquatic organisms (LC50: 0.6 ug/L such as chrysenes) Impacts • oil exposure to fish caused by edema (fluid accumulation), cardiac toxicity, tissue death, and abnormal development; Oil can kill fish food (zooplankton) • oil can be accumulated in the food chain (algae-zooplanktoninvertebrates-fish-birds) and can be transferred to humans • Corals exposed to oil showed mortality, decreased growth rates; decreased lipid content; decreased survival of larvae, decreased gonadal development and increased bleaching • Seagrasses are sensitive to oil exposure leading to decreased growth rates, smothering (suffocating) of leaves, changes in the chlorophyll content ofGolamKibria_Oil leaves and reduced spill_oil pollution_DOI:photosynthetic ability 114 10.13140/RG.2.2.14293.06886 21 Nov18

Take Home Messages

Impacts • mangrove plants may die from suffocation (reducing O2 flow), starvation, yellowing (chlorosis), increases rates of defoliation, pneumatophores reduction, reduces photosynthetic efficiency and other physiological/toxicological impact; • Oil physically can cover mangrove plants, their roots (pneumatophores) Reducing oil spill impacts • booms and skimmers (to contain oil), • dispersant (smaller droplets, disperse by wind, wave, currents); • offshore burning (to remove the large quantity of oil quickly); • natural recovery (to slow degradation, natural removal by waves, currents), • manual oil removals (using hand tools and manual labour); • sorbents (using peat, wood, cotton, straw, corncob, shredded sugarcane), • vacuuming (to remove pooled oil or thick oil) GolamKibria_Oil spill_oil pollution_DOI: 115 • biodegradation (by microorganisms, such as bacteria) 10.13140/RG.2.2.14293.06886 21 Nov18