the toxic truth - Greenpeace

the toxic truth
What is known about the waste
The waste present in the slop tanks arriving in
Abidjan consisted of an oily liquid layer (also
referred to as organic phase or hydrocarbon
phase) and an aqueous phase (also referred
to as the watery phase or spent caustic). The
oily liquid layer was on top of the aqueous
layer. The very bottom layer most probably
consisted of sediments, at least part of which
were not offloaded and dumped in Abidjan, as
the sediments remaining on board became
subject to a dispute one month later when
the ship was in Estonia. The total amount of
waste dumped in Abidjan has been estimated
to be approximately 516mt (528m 3 ). 6
The Netherlands Forensic Institute analyzed
samples taken from the oily liquid and
aqueous layer of the waste present in the
slop tanks when the Probo Koala was in
Amsterdam from 2 to 5 July in 2006. The NFI
analysis was completed by three laboratories
– Caleb Brett, Saybolt and Omegam.
The NFI identified the waste in the Probo
Koala’s slop tanks as “a combination of
an oily liquid and water, with a whole range
of impurities. The oily liquid consists of
a hydrocarbon mixture which, in terms of
composition, shows many similarities to
a naphtha-like product from the cracking
installation of a refinery. The composition of
the water shows a high degree of similarity to
spent caustic (a waste stream resulting, inter
alia, from washing of the naphtha stream from
refinery cracking installation):
» pH is 14
» Chemical Oxygen Demand (COD) of
720,000mg/l
» 10% sodium hydroxide
» 4.8% phenols (including thiophenols and
phenylmercaptans)
» 3.5% mercaptan-sulphur (including
phenylmercaptans or thiophenols)
» 0.5% hydrogen sulfide.” 7
The organic compounds in the watery phase
of the waste were found after acidification of
the samples with a hydrochloric acid solution.
Hydrogen sulphide, mercaptans, phenols and
thiophenols were detected in the acid form.
In the alkaline watery phase of the samples
these components appear in the basic form,
namely as sulphide, mercaptide, phenolate
and thiophenolate. 8
Despite over a period issuing public
statements suggesting that the waste
dumped in Abidjan was just ordinary ship’s
slops and not toxic, Trafigura have admitted in
documents obtained from the UK court that
the chemical composition showed the waste
was not ordinary ship’s slops.
On 3 December 2008, Trafigura responded
to amended requests for clarification of the
defence from Leigh, Day & Co by submitting a
list entitled “Likely Chemical Composition of
the Slops”, which it said was “based on the
NFI analysis”. 9 The list, which is reproduced
on page 208, essentially adopts the NFI
analysis and then applies the percentages to
the 379 metric tons of aqueous waste and the
137 metric tons of hydrocarbon waste with a
different composition.
In its defence in the case against the BBC in
November 2009, Trafigura again agrees that
the NFI analysis is the best available evidence
of the composition of the waste. It also states
that the sample taken by CIAPOL from the
Probo Koala waste on 21 August 2006 should
not be considered a reliable analysis. 10
The likely chemical composition of the
aqueous and hydrocarbon phases of the
slops, as accepted by Trafigura:
207
ANNEX I