Ex­po­sure to di­luted bi­tu­men deadly for salmon, study finds

The Prince George Citizen - - News - Dirk MEISSNER

VIC­TO­RIA — A spill of di­luted bi­tu­men puts the sur­vival of young salmon at risk even if the fish end up in clean wa­ter fol­low­ing ex­po­sure to the oil prod­uct, says new re­search from the Univer­sity of Guelph.

Re­searchers said they made the con­clu­sions af­ter ex­pos­ing four groups of sock­eye salmon eggs to four dif­fer­ent amounts of wa­ter sol­u­ble di­luted bi­tu­men and ob­served the young fish af­ter the eggs hatched for up to eight months in clean wa­ter.

“We saw a lot of changes dur­ing the ex­po­sure,” said Sarah Al­der­man, a post-doc­tor­ate re­searcher at the Univer­sity of Guelph’s depart­ment of in­te­gra­tive bi­ol­ogy. “We found a whole suite of ef­fects from de­layed hatch­ing to in­creased mor­tal­ity, in­creased de­vel­op­men­tal de­for­mi­ties and changes in growth and en­ergy stores in the fish.”

The re­sults are based on the con­cen­tra­tions of poly­cyclic aro­matic hy­dro­car­bons mea­sured in the wa­ter, which are a ma­jor toxic com­po­nent of pe­tro­leum prod­ucts, said Al­der­man.

She said al­most 50 per cent of the salmon ex­posed to the high­est amount of bi­tu­men died dur­ing the first two months af­ter they were moved to clean wa­ter and ob­served for up to eight months.

“We found for about the first two months af­ter mov­ing them to clean wa­ter we had re­ally high mor­tal­ity even though they are not be­ing ex­posed to the dil­bit (di­luted bi­tu­men) any­more,” said Al­der­man. “We saw mor­tal­ity as high as 50 per cent dur­ing that two-month pe­riod. Ev­ery day there’s more dead and more dead.”

The re­search was pub­lished this month in the peer-reviewed jour­nal Aquatic Tox­i­col­ogy.

About 1,000 sock­eye eggs were used in each of the four ex­po­sure tests, with the amounts rang­ing from four mi­cro­grams of poly­cyclic aro­matic hy­dro­car­bons per litre of wa­ter to 35 mi­cro­grams per litre to 100 mi­cro­grams per litre, Al­der­man said. The fourth group of eggs was not ex­posed to the prod­uct.

Al­der­man said the largest ex­po­sure amount of 100 mi­cro­grams per litre re­flected the level of oil prod­ucts mea­sured along the shore­line of the Gulf of Mex­ico fol­low­ing the Deep Wa­ter Hori­zon spill in 2010.

She said mor­tal­ity among the un­ex­posed sock­eye eggs was less than two per cent.

In the ex­posed fish, the re­searchers also found changes in brain de­vel­op­ment and over­all per­for­mance lev­els in the young sock­eye that sur­vived the di­luted bi­tu­men ex­po­sure, said Al­der­man.

“It’s re­ally af­fect­ing mul­ti­ple body sys­tems in lots of dif­fer­ent ways.”

The re­sults from the study come as fed­eral and pro­vin­cial gov­ern­ments, First Na­tions, en­vi­ron­men­tal groups and en­ergy com­pa­nies are locked in a con­tentious de­bate over the en­vi­ron­men­tal and eco­nomic vi­a­bil­ity of the pro­posed ex­pan­sion of the Trans Moun­tain pipe­line from north­ern Al­berta to Burn­aby.

In a re­cent de­ci­sion over­turn­ing the ap­proval of the pipe­line ex­pan­sion, the Fed­eral Court of Ap­peal said the Na­tional En­ergy Board un­jus­ti­fi­ably ex­cluded the con­sid­er­a­tion of ma­rine ship­ping of bi­tu­men in its ap­proval process. The court said the board failed to con­sider its obli­ga­tions un­der the Species at Risk Act in re­la­tion to south­ern res­i­dent killer whales.

First Na­tions said dur­ing the en­ergy board’s hear­ings that there were re­search and in­for­ma­tion gaps about a spill of di­luted bi­tu­men in a ma­rine en­vi­ron­ment. The Fed­eral Court rul­ing said there was noth­ing in the ap­proval process that showed the gov­ern­ment ad­dressed those con­cerns.

Bi­tu­men has the con­sis­tency of crum­bling as­phalt and doesn’t flow freely like oil. It needs to be di­luted with an­other pe­tro­leum prod­uct to al­low it to flow through pipe­lines.

The fed­eral gov­ern­ment agreed last June to buy the ex­ist­ing pipe­line, the ex­pan­sion project and ter­mi­nals from Kinder Mor­gan Canada for $4.5 bil­lion af­ter the com­pany threat­ened to walk away from the Trans Moun­tain ex­pan­sion project in April.

Al­der­man said the ex­po­sure lev­els of di­luted bi­tu­men were mod­elled on prospec­tive amounts from a po­ten­tial pipe­line spill. She said the re­search shows the need to have clean up mea­sures in place.

“There’s a lot of dil­bit be­ing trans­ported in pipe­lines and most of it is trans­ported very safely,” Al­der­man said. “But as this in­dus­try ex­pands the po­ten­tial for spills in­creases. We’re work­ing to un­der­stand what to ex­pect if it does hap­pen.”


Spawn­ing sock­eye salmon are seen mak­ing their way up the Adams River in Roderick Haig-Brown Pro­vin­cial Park near Chase, B.C. in 2014. A spill of di­luted bi­tu­men puts the sur­vival of young salmon at risk even if the fish end up in clean wa­ter fol­low­ing ex­po­sure to the oil prod­uct, says new pipe­line pol­lu­tion re­search from the Univer­sity of Guelph.

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