Caspian Sea: State of the Environment 2019

The outcomes for samples taken from different areas of water are shown in Table 5.9. As the ta- ble demonstrates, changes in pollutant concen- trations are quite wide-ranging and bear little

Total petroleum hydrocarbons and concentra- tions of heavy metals (copper, nickel, chromi- um6+, manganese, zinc, lead and cadmium) in the bottom sediment samples were analysed.

Table 5.10: Organic pollutant content of bottom sediments of the north-western part of the Caspian Sea, 2012–2014.

September– October 2012

November– December 2012

September– October 2013

August– December 2014

Pollutant

Total PAH, µg/kg

2.4–242

17.3–699

<0.03–309

<0.03–531

Total PCBs, µg/kg

<0.03–6.70

0.35–10.8

<0.03–2.12

0.10–2.50

Hexachlorobenzene, µg/kg

<0.03–0.2

<0.03–0.25

<0.03–0.3

<0.03–0.40

Total DDT, µg/kg

<0.03–1.15

<0.03–4.72

0.11–1.74

<0.03–6.50

Total HCH, µg/kg

<0.05

<0.05

<0.05–0.21

<0.05–1.80

Phthalates, µg/kg

380–3,920

130–17,210

70–2,320

Source: Reviews of the state and pollution of the marine environment of the north-western part of the Caspian Sea in 2012–2014 (Monakhov 2014a; Monakhov 2014b; Monakhov 2015).

Table 5.11: Main indicators of sea bottomsediment contaminants around oil and gas fields (Filanovsky oilfield and Korchagin oilfield in 2017, compared with historical and contemporary background concentrations).

Concentration in 2017

Background concentration

Indicator

Filanovsky Field

Korchagin Field

Contemporary **

Historical *

1.37…12.7

0.4…11.1

0…57.0

0…68.0

Oil products, mg/kg

10.8…31.7

8.4…25.3

0…120

0.50...66.0

Surfactants, mg/kg

0…1.68

0…26.5

0…506

0…313

Total PAH, μg/kg

8.4…20.4

4.0…125

0…226

1.10…166

Zinc, mg/kg

5.70…19.2

5.6…41.0

0…48.0

3.30…54.0

Nickel, mg/kg

2.40…5.50

2.80…13.0

0…70.0

3.70…55.0

Copper, mg/kg

1.50…5.30

1.0…6.30

0.60…32.0

0…35.0

Lead, mg/kg

0.11…0.28

0.10…0.23

0.02...0.65

0…8.00

Cadmium, mg/kg

56…497

58…471

0…3,100

–

Barium, mg/kg

* LUKOIL data for 1998–2009 (LUKOIL-Nizhnevolzhskneft n.d.) ** Roshydromet data (Monakhov 2014a; Monakhov 2014b; Monakhov 2015) Source: Kuzin 2018.

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