J
Methods Used To Estimate PAH Loadings to the Marine Environment

To understand the toxic effects of petroleum hydrocarbon releases to the coastal ocean, one has to examine the loading of the more toxic components of the hydrocarbon mixture. Since PAH are thought to be responsible for many of the biological effects of petroleum, the committee estimated PAH loads from various petroleum sources. This refinement of the 1985 National Research Council (NRC) report is a step toward a more rigorous risk assessment of petroleum releases to the coastal oceans. For many of the source types, including natural seeps, platforms (offshore andcoastal), pipelines (offshore and coastal), produced waters, vessel spills, vessel operations, aircraft dumping, two-stroke engines, vessels of less than 100 GT, and coastal facilities, PAH loadings were estimated as a fraction of the total petroleum hydrocarbon loadings, based on measured PAH content of crude oils and refined petroleum products. Environment Canada has measured the amount of a standard suite of PAH listed in Table J-1 in a variety of oils. These data were used to estimate the average total PAH amounts in five types of oils: crude oil, heavy distillates, light distillates, jet fuel, and lube oil (Table J-2). Additionally, the PAH content of gasoline was assumed to be negligible. The best estimates of petroleum hydrocarbon inputs to the sea by the sources discussed above were broken down into the six oil types (crude oil, heavy distillates, light distillates, jet fuel, lube oil, and gasoline), which were then multiplied by the appropriate fractions of PAH in the six types of oil to estimate the PAH contributions to the sea by source.

PAH loadings to North American coastal waters from the atmosphere were calculated for 21 individual PAH based on estimated PAH levels in the coastal atmosphere (Table 2-; see Chapter 3 and Appendix B for details). Because coastal waters are undersaturated with dissolved PAH relative to the overlying atmosphere, there is a significant net transfer of atmospheric PAH to the oceans. PAH loadings from land-based sources were estimated by assuming that the PAH load from each river is proportional to the estimated petroleum hydrocarbon loading (see Chapter 3 and Appendix I for details).

TABLE J-1 PAH Compounds Measured by Environment Canada

Naphthalene

C0-N

C1-N

C2-N

C3-N

C4-N

Phenanthrene

C0-P

C1-P

C2-P

C3-P

C4-P

Dibenzothiophene

C0-D

C1-D

C2-D

C3-D

Fluorene

C0-F

C1-F

C2-F

C3-F

Chrysene

C0-C

C1-C

C2-C

C3-C

Other PAH

Biphenyl

Acenaphthalene

Acenaphthene

Fluoranthene

Pyrene

Benz[a]anthracene

Benzo[b]fluoranthene

Benzo[k]fluoranthene

Benzo[e]pyrene

Benzo[a]pyrene

Perylene

Indeno[1,2,3cd]pyrene

Dibenz[a,h]nthracene

Benzo[hi]erylene



The National Academies | 500 Fifth St. N.W. | Washington, D.C. 20001
Copyright © National Academy of Sciences. All rights reserved.
Terms of Use and Privacy Statement



Below are the first 10 and last 10 pages of uncorrected machine-read text (when available) of this chapter, followed by the top 30 algorithmically extracted key phrases from the chapter as a whole.
Intended to provide our own search engines and external engines with highly rich, chapter-representative searchable text on the opening pages of each chapter. Because it is UNCORRECTED material, please consider the following text as a useful but insufficient proxy for the authoritative book pages.

Do not use for reproduction, copying, pasting, or reading; exclusively for search engines.

OCR for page 253
Oil in the Sea III: Inputs, Fates, and Effects J Methods Used To Estimate PAH Loadings to the Marine Environment To understand the toxic effects of petroleum hydrocarbon releases to the coastal ocean, one has to examine the loading of the more toxic components of the hydrocarbon mixture. Since PAH are thought to be responsible for many of the biological effects of petroleum, the committee estimated PAH loads from various petroleum sources. This refinement of the 1985 National Research Council (NRC) report is a step toward a more rigorous risk assessment of petroleum releases to the coastal oceans. For many of the source types, including natural seeps, platforms (offshore andcoastal), pipelines (offshore and coastal), produced waters, vessel spills, vessel operations, aircraft dumping, two-stroke engines, vessels of less than 100 GT, and coastal facilities, PAH loadings were estimated as a fraction of the total petroleum hydrocarbon loadings, based on measured PAH content of crude oils and refined petroleum products. Environment Canada has measured the amount of a standard suite of PAH listed in Table J-1 in a variety of oils. These data were used to estimate the average total PAH amounts in five types of oils: crude oil, heavy distillates, light distillates, jet fuel, and lube oil (Table J-2). Additionally, the PAH content of gasoline was assumed to be negligible. The best estimates of petroleum hydrocarbon inputs to the sea by the sources discussed above were broken down into the six oil types (crude oil, heavy distillates, light distillates, jet fuel, lube oil, and gasoline), which were then multiplied by the appropriate fractions of PAH in the six types of oil to estimate the PAH contributions to the sea by source. PAH loadings to North American coastal waters from the atmosphere were calculated for 21 individual PAH based on estimated PAH levels in the coastal atmosphere (Table 2-; see Chapter 3 and Appendix B for details). Because coastal waters are undersaturated with dissolved PAH relative to the overlying atmosphere, there is a significant net transfer of atmospheric PAH to the oceans. PAH loadings from land-based sources were estimated by assuming that the PAH load from each river is proportional to the estimated petroleum hydrocarbon loading (see Chapter 3 and Appendix I for details). TABLE J-1 PAH Compounds Measured by Environment Canada Naphthalene C0-N C1-N C2-N C3-N C4-N Phenanthrene C0-P C1-P C2-P C3-P C4-P Dibenzothiophene C0-D C1-D C2-D C3-D Fluorene C0-F C1-F C2-F C3-F Chrysene C0-C C1-C C2-C C3-C Other PAH Biphenyl Acenaphthalene Acenaphthene Fluoranthene Pyrene Benz[a]anthracene Benzo[b]fluoranthene Benzo[k]fluoranthene Benzo[e]pyrene Benzo[a]pyrene Perylene Indeno[1,2,3cd]pyrene Dibenz[a,h]nthracene Benzo[hi]erylene

OCR for page 253
Oil in the Sea III: Inputs, Fates, and Effects TABLE J-2 Oils or Refined Products Used to Calculate Amount of PAH in Different Petroleum Hydrocarbons Discussed in This Report Oil type References (see codes) Estimated PAH in oil Crude (average of heavy and light crudes) 0.013908 Heavy crudes Alberta Sweet Mix Blend (ASMB) a,b   Arabian Light c,d,e   Arabian Light (Mackay) c,d,e   Brent oil (British) b   Granite Point, Cook Inlet b,f,g   Trading Bay, Cook Inlet b,f,g   Swanson River, Cook Inlet b,f,g   Federated h,i   Gul1faks oil (Norwegian) b   Norman Wells j,k,l   Nipisi oil m   Northern Pipeline b   Middle Pipeline b   Southern Pipeline b   Sahara Crude from Norway b   Statfjord (Norwegian) b   Prudhoe Bay from biodegradation j,k,l   Osenberg j,k,l   Bent Horn j,k,l   Light crudes Arabian Medium Crude b   Hedrun Crude b   Hibernia j,k,l   Lloydminster oil j,k,l   Terra Nova j,k,l   Russia Komi after water correction b   Heavy distillates (average of Bunker C and fuel oil marine diesel) 0.024256 Bunker C ESD Bunker C b,s   Bunker C from biodegradation j,k,l   1998 Quebec spill Bunker C type t   Irving Whale oil u   Fuel oil marine diesel Bunker C and diesel mixture b,f,g   Motor Vessel (MV) Attona b   MV Western b   MV-Paean vessel reduced b   MV-Paean vessel b   Intermediate Fuel Oil-30 viscosity b   Valery Chkalov b   Light distillates 0.034441 Diesel No. 2 b,f,g   Diesel spill from Quebec 1998 o,p   Mobile burn 97 diesel q   Mobile burn 98 diesel r   Jet fuel 0.028373 Jet B fuel f,g   Lube oil 0.000118 Lube oil j,k,l,n   Reference codes: aWang et al. (1994); bWang et al. (1999a); cWang (1998b); dWang et al. (2000c); eWang et al. (in press); fWang et al. (1997a); gBlenkinsopp et al. (1997); hWang (1999); iWang et al. (2001); jWang (1994b); kWang (1994c); lWang et al. (1998a); mWang et al. (1998b); nWang (1994a); oWang (1998a); pWang et al. (2000b); qWang et al. (2000a); rWang (2000); sWang et al. (1997b); tWang et al. (1999b); uWang (1995)