Polychlorinated dioxin and dibenzofuran levels in the environment and food from the republic of Bashkortostan, Russia

Chemosphere, Vol. 31, Nos 9-12, pp. 1699-1708, 1998 0 1998 Elsevier Science Ltd AH rights reserved. Printed in Great Britain W5-6535/98 $19.00+0.00

PII: SOO45-6535(98)00235-5

POLYCHLORINATED

DIOXIN AND DIBENZOFURAN

AND FOOD FROM THE REPUBLIC Valerie Maystrenko”,

Edward Rruglo?,

LEVELS IN THE ENWRONMENT

OF BASHKORTOSTAN,

RUSSIA

Zarema Amirova’ and Rustem Rhamitov3

‘Institute for Problems of Applied Ecology and Natural Resources Use of the Republic of Bashkortostan, 12/l, 8 Marta St., 450005, Ufa, Bashkortostan, Russia ‘Research Centre for Environmental Protection of the Republic of Bashkortostan, 147, October Av., 450075, Ufa, Bashkortostan, Russia 3Ministry of Emergencies and Environmental Safety of the Republic of Bashkortostan, 12/l, 8 Marta St,, 450005, Ufa, Bashkortostan, Russia

ABSTRACT The paper summarises systematic 5-year monitoring of the environment,

drinking water and food for PCDDs

and PCDFs levels in industrial centres and in rural areas of the Republic of Basbkortostan, presents

selected

data on dioxin concentrations

plants. The paper gives a comparative cities for Bashkortostan PCDDaPCDFs

in gas emissions

analysis of PCDDs/PCDFs

and for industrial countries

levels in the environment,

Russia. It also

of toxic waste incinerators

at chemical

daily intake by the population

of industrial

of Europe and North America. The results show that

drinking water and food in Bashkortostan

are approximately

equal

to those in other industrial countries. 01998 Elsevier Science Ltd. All rights reserved INTRODUCTION The Republic of Bashkortostan is located approximately with high concentration

is situated on the border of Europe and Asia. Ufa, the capital of the Republic,

1200 km east of Moscow,

west of the Ural Mountains.

Bashkortostan

of chemical and oil-refining plants. The majority of the plants are situated along the

Belaja river and they discharge their wastes right into the river and the atmosphere. large chlororganic The contamination

program

dibenzotirans

of the environment,

drinking water and food in Bashkortostan

was initiated

in the 1990s after the detection

in drinking water in Ufa5*6. At that time hazardous agents production

Bashkortostan

a program

launched

and human health.

by polychlorinated

dioxins

(PCDFs) was considered at symposiums on dioxins and related compoundslA.

involved in chlororganic

compounds

Among them there are

chemical plants. All this results in hazardous impact on the environment

(PCDDs) and dibenzoftuans research

is a region

in the environment.

of relatively high levels of dioxins and impact on the health of the workers

was also revealed ‘,‘. In 1993 the Parliament

“Dioxin”- the program

A

of monitoring

of the Republic of

dioxins and others chlorinated

During 1990-1996 more than 1000 samples of water, soil, air and food were 1699

1700 analyzed. The main items of the program are: - the detection of PCDDs/PCDFs

and the assessment

- the assessment of the dioxin contamination - the assessment of the population The dioxin analytic procedure PCDFs were extracted correction

of the environment;

health.

was carried out according

by organic

solvents.

of errors in the process

GC-MS determination

to the standard method EPA 1613. PCDDs and

‘3C-labelled dioxins and Ruans were added to samples for

of the extraction

procedure we used column chromatography the use of a high-resolution

of their emission;

and during clean-up

procedures.

For the clean-up

on silica gel, charcoal and ahnnina. Samples were analysed with

double-focusing

magnetic mass spectrometer

( MS VG-Autospec-Ultima).

For

of PCDDs and PCDFs we used a 60m capillary column containing a non-polar DB-5

stationary phase. EMISSION The main sources plants

of the environmental

“Khimprom”

chlororganic

contamination

in Ufa and “Kaustik”

by PCDDs/PCDFs

in Sterlitamak.

in Bashkortostan

are chemical

These plants have been producing

different

chemicals including pesticides 2,4-D and 2,4,5-T at various times for more than 40 years’-“. In

the process of production

of these chemicals the dioxins and dibenzofurans

are formed; further on they are

extracted by charcoal filters and the residual amounts are imported to biological water treatment installations. Residues in the form of sludge are stored at special disposal sites, For the period of “Khimprom” operation there has been accumulated

about 530 000 m3 of sludge with the dioxin content of 7-21 ppb (TEQ). The

plant territory and premises are also highly contaminated of dioxin emission.

with dioxins and dibenzofurans,

the secondary

sources

trichlorphenols

contains about 300 ppt of 2,3,7,8-tetrachlordibenzodioxin

premises of these installations 2,3,7,8-TCDD

Thus, the soil around the installations

than 40 years contamination

of operation

of the plants

of the environment

producing

chlororganic

in industrial centres of Bashkortostan

to these plants. The analytical data on dioxin and dibenzofuran incinerators

at “Khimprom”

PCDDs/PCDFs

and “Kaustik”

in 1990 at “Khimprom”

are given in Table

producing

2,4-D and

(TCDD). The lime plaster of the

contains more than 570 ppb of 2,3,7,8-TCDD.

are discharged into the atmosphere by exhaust-ventilation

and they are as well

The considerable

amounts of

fans - from 3 10 to 950 pg/m3. More chemicals

have resulted

in dioxin

and in agricultural regions adjacent

gas emissions

discharged

1. It was found

was about 900 g (total PCDDs/PCDFs).

by toxic waste

that the emission

of

At present the plant is

operating only periodically and according to the available information the dioxin emission is about 50 g per year (total PCDDs/PCDFs). Other dioxin emission

sources

(industrial

and domestic

considerable impact on the dioxin environmental America, the Republic of Bashkortostan dioxin

contamination

waste, metallurgical

contamination.

Unlike the industrial countries of Europe and

has no domestic waste incinerators

of the environment

in those

and cement plants) have no

countries.

It should

which are the main sources of be marked

that

considerable

1701 Table 1 The PCDDs/PCDFs content in gas emissions from chemical plants “Khimprom” in Ufa and “Kaustik” in Sterlitamak, pg/m3

Isomers

Chlororganic waste incinerator at “Kaustik”

Production of glycerol at “Kaustik”

52 50 57

10.3 33.8

2,3,7,8-TCDD 12 9 ,3 ,7 98-PeCDD 123478-HxCDD >>3, > 1,2,3,6,7,8_HxCDD 123789-HxCDD 1, , f > 1,2,3,4,7,8,9_HpCDD OCDD 2,3,7,8-TCDF 12 7 ,3 >7 98-PeCDF 2 73 94 ?7 98-PeCDF 123678-HxCDF >>>, 7 1,2,3,4,7,8_HxCDF 2,3,4,6,7,8-HxCDF 1,2,3,7,8,9_HxCDF 1,2 >3 ,4 76 17,8-HpCDF 1,2,3,4,7,8,9-HpCDF OCDF

TEQ

amounts of dioxins are discharged

Gas emissions at “Khimprom”

13 209 732 2765 2129 1106 2995 5157 103 624 44112 4141 37694

16.5 13.3 46.9

11.0 8.2 96

142 1060 286 136 379 284 103 265 334 242 108 96 19 7 435 75 513

243 1

10.6

970

into the atmosphere

by automobile transport.

Studies have shown that the

dioxin content in the air of Ufa highways is about 1 pg TEQ/m3 WATER Discharges

of dioxins with waste waters and gas emissions from Whimprom”

dioxin contamination

of open aquatic bodies and reservoirs.

and “Kaustik” resulted in

The first reports on dioxins and dibenzofurans

in

the water of the Belaja river and the Ufa river appeared in 1990. For the period of 1994- 1997 more than 250 samples

of drinking

PCDDs/PCDFs approaches

water

from

and ruial

regions

of Bashkortostan

levels. The studies have shown that the real PCDDs/PCDFs

the analytical detection

measurements

urban

exceeds

have been

analysed

for

content in the drinking water

limit or is even lower (Table 2). The toxic equivalent in none of 250

1 ppq (for the calculation

of the non-detectable

detection limit was used). In other places of Bashkortostan

PCDDs/PCDFs

isomers concentration concentrations

the one-half

are also within the

detection limit, except for OCDD (11.5 pgA). The tap water samples from the rural regions beyond the Ural may be considered these

samples

only OCDD

is detected

at the level of 0.3-0.5

as being background,

pgA. In the river water

samples

in the

1702 Table 2 The PCDDs/PCDFs content in the drinking water of Ufa and the background in the Republic of Bashkortostan, ppq. I

I

I

PCDDsJPCDFs

level

Ufa, n = 250, 1994-1997

Background,

I

n = 5, 1996

TCDD

ND* (0.1-0.3)

ND (0.06)

PeCDD HxCDD

ND (0,l - 0.4)

ND (0.09)

ND (0.3 -1.6)

ND(O.1)

HpCDD

ND (0.2 - 2.7)

ND (0.45)

OCDD

1.11-4.95

0,97

TCDF

ND (O.l)-3.2

ND (0.05)

PeCDF

ND (0.07) - 3.95

ND (0.05)

HxCDF

ND (0.6)-2.23

ND (0.04)

HpCDD

ND (O.l)-1.64

ND (0.3)

OCDF

ND (0.4) - 4.25

0.52

* Not detected

PCDDs/PCDFs

content is higher (Table 3) and reaches the value of 5 pg TEQ/I. The dioxins mainly come to

the river water with the air, and in spring-time

- with surface and ground

practically in all samples the share of mrans in the total concentration

waters.

It is interesting

that

is about twice as large as that of

dioxins. By dioxin content the samples represent two groups of rivers: the so-called “clean rivers” and those affected by contamination characteristics

sources.

The content

of PCDDs/PCDFs,

depending

on physical and chemical

of the substances suspended in the river water, amounts to 50-60 % of the total contamination

of the sample. The main results of the river water monitoring are as follows: - the analyses of PCDDs/PCDFs particles

in the samples of natural water both prepared and original with suspended

have shown, that the content

detecting limit of methods,

of toxicants

and the background

in rivers, lakes and rills in Bashkortostan

is at the

level is 1 pgA (TEQ) for the drinking water and < 6 pgA for

the river water; -the isomer profile of the PCDDs/PCDFs the main sources of contamination process into dioxin contamination

distribution in the rivers of Bashkortostan

due to limited data, but it is clear that the contribution of the waterways in Bashkortostan,

of the low content of Cl7 - and Cl8 - PCDDs/PCDFs -the analyses of the samples from downstream of technogenic

doesn’t allow to identify of the incineration

is of relatively low importance because

isomers, registered in all samples;

sites affected by industrial contamination

point to the sources

character, but the information only on water samples is not sufficient for their identification.

The available information

on the dioxin contamination

of water in various countries l1 also allows to make a

conclusion that: - in drinking water the PCDDs/PCDFs

were not often detected at the level of 1 ppq and above;

1703 Table 3 The PCDDs/PCDFs

content in the river water of the Republic of Bashkortostan, Place of sampling

River.

Belaja

ppq

CPCDD

CPCDF

EQ

24.4

40.0

4.9 2.6

On the border with the Tatarstan Republic

Uruzan

In the Ural Mountains

9.7

18.8

Ai

In the Ural Mountains

15.1

34.9

5.2

Ufa

In the Ural Mountains

10.8

18.4

2.9

Sakmara

On the border with Orenburg region

10.7

19.1

2.3

Zilair

Below Zilair city

18.4

17.7

2.3

Suren

On the border with Orenburg region

7.1

14.6

2.7

- the PCDDs/PCDFs

contamination

of unprepared

- in surface waters the concentration

water samples was higher than that of prepared ones;

of PCDDs/PCDFs

is increasing usually from tetra- to octa-chlorinated

groups and congeners. SOIL The analyses of the soil taken in Ufa and Sterlitamak urban territories concentrations

indicate that the dioxin concentration

in the soil of

is at the level of 1 to 20 ppt (TEQ) and does not exceed the norms for Russia. High of dioxins and dibenzofiuans

are detected only in industrial zones adjacent to chemical plants -

280-290 ppt (TEQ). In most of agricultural regions the dioxin content in the soil is 0.25 - 1.2 ppt (TEQ) and does not exceed the allowable level of 10 ppt (TEQ) (Table 4). The main source of dioxin ingress into the soil in agricultural regions of Bashkortostan

is 2,4-D in which the content of PCDDs/PCDFs

(TEQ). It should be noted that in European PCDDs/PCDFs chemicals

in the soil of industrial

content

scattering as compared waste

Bashkortostan

countries

in Bashkortostan

in these

there are no incinerators

the mean concentration

are apparently

sources (mainly chemical plants producing

to industrially developed

incinerators

American

regions is 3.8 - 8.1 ppt (TEQ) 11, Relatively

in the soil of urban territories

localization of the dioxin discharge

domestic

and North

European

countries

countries.

should

is 0.1-0.2 ppb

low levels of these

accounted

for by the

chlorine) and by their spatial

The emission of PCDDs/PCDFs

also be taken

into

consideration,

in

at all.

This is due to sufficiently lower application of chlorine-containing of Bashkortostan

from

while

The given data also show that the mean dioxin content in the soils of rural regions is at the background

the agriculture

of

as compared

to Germany

pesticides

(approximately

and the Netherlands.

level.

by 10 times) in

In the regions

pesticides are used at a larger scale some soil samples contain up to 1.2 ppt (TEQ) of PCDDs/PCDFs.

where

1704 Table 4 The mean PCDDsJPCDFs

content in the soil of industrial centres and agricultural regions, ppt

Isomers

Industrial centres

Farm regions

Natural reserves

2,3,7,8-TCDD

0.61

0.06

0.05

1,2,3,7,8-PeCDD

0.16

1,2,3,4,7,8HxCDD

0.74 0.19

0.22

1,2,3,7,8,9HxCDD

0.19

0.37

0.37

1,2,3,4,7,8,9_HpCDD

14.2

0.41

0.27

OCDD 2,3,7,8-TCDF

81.1

2.30

0.62

5.52

0.07

0.04

1,2,3,7,8-PeCDF

1.30

1,2,3,6,7,8HxCDD

2,3,4,7,8-PeCDF

1.48

1,2,3,6,7,8HxCDF

2.07

1,2,3,4,7,8HxCDF

0.09 0.34

0.12

0.62

0.19

2,3,4,6,7,8HSDF

1.40

0.21

1,2,3,7,8,9HxCDF

1.42

0.50

1,2,3,4,6,7,8_HpCDF

15.72

0.47

1,2,3,4,7,8,9_HpCDF

2.24

0.25

OCDF

38.6

1.91

0.31

TEQ

3.24

0.35

0.15

Data on vertical migration of dioxins was also obtained. They are mostly concentrated with the maximum concentration solvents and oil products,

at the depth of 40 cm. However,

0.09

in the upper soil layer

if the soil is contaminated

with organic

the dioxin migration increases. Thus in the territory of the industrial and domestic

waste disposal site in Ufa PCDDs/PCDFs

were detected at the depth of 8-10 m. AIR

There is not so much data on the content of dioxins in the air as compared to water and soil. It is defined that in the air of residential districts of industrial centres in Bashkortostan not exceed 0.15 pg TEQ/m3. However,

in the territory

the PCDDs/PCDFs

of “Khimprom”

concentration

does

and “Kaustik” this value is much

higher. When moving away from industrial zones the dioxin content in the air is rapidly decreasing. Thus if in the territory of “Kaustik” the dioxin concentration

in the air is 0.5 - 1.0 pg TEQ/m3 then at the distance of 5

km away from the plant it is 0.03 pg TEQ/m3. The dioxins fallout from the air to the soil is decreasing with the increase of the distance in the leeward direction according to the exponential law. Alongside with measurements into consideration.

of the dioxin concentration

In Bashkortostan

in the air the data of snow analyses were also taken

snow is lying from November

to March.

Owing to this fact the

1705 Table 5 The mean PCDDs/PCDFs

content in the air of residential districts of the Republic of Bashkortostan, World wide”

North America”

2,3,7,8-TCDD

0.0100

0.0107

0.004

co.01

1,2,3,7,8-PeCDD 1,2,3,4,7,8_HxCDD

0.0297

0.0316

0.0036

0.013

0.023 1

0.0246

0.0025

0.057

1,2,3,6,7,8_HxCDD

0.0350

0.0372

0.0050

0.020

1,2,3,7,8,9_HxCDD

0.0458

0.0489

0.003 1

0.013

1,2,3,4,7,8,9_HpCDD

0.5472

0.5828

0.0660

0.017

OCDD

2.655 1

2.8386

0.1598

1.813

2,3,7,8-TCDF

0.1128

0.1128

Isomers

Europe”

pg/m3

The Republic of Bashkortostan

1,2,3,7,8-PeCDF

0.0498

0.0498

2 13 ,4 >7 >8-PeCDF

0.0274

0.0287

0.0098

0.030

1,2,3,6,7,8_HxCDF

0.0548

0.0585

0.065 1

0.032

123478-HxCDF >, >>>

0.0604

2,3,4,6,7,8_HxCDF

0.0420

0.0604 0.0448

0.0039

0.046

1,2,3,7,8,9_HxCDF

0.0147

0.0157

0.0006

0.041

1,2,3,4,6,7,8_HpCDF

0.1995

0.2102

0.0542

0.084

1,2,3,4,7,8,9_HpCDF

0.0279

0.0019

0.012

OCDF

0.1597

0.0299 0.1686

0.0094

0.130

TEQ

0.0905

0.0948

0.0105

0.066

contamination

of the snow cover is an indicator of the atmosphere

the dioxin emission. Besides, determination in dioxins transportation.

0.024

0.065

contamination

and it allows to judge about

of the dioxin content in snow allows to clarify the role of rainfalls

In particular, the assessment

of the air contamination

close to “Khimprom” and in

places distant from it was made as a result of analysing the snow cover. It was detined that in the territory of “Khimprom” the dioxin contamination data on the levels Bashkortostan

of dioxin

of snow is by 2 orders higher than in residential districts. The available

concentration

in the air of residential

testily to the fact that they are comparable

districts

with the respective

in industrial

centres

of

values for industrial countries

of Europe and USA” (Table 5). FOOD First analyses of PCDDsiPCDFs with the assessment

content in foodstuffs of Bashkortostan

were made in 1993. It was connected

of the impact of dioxin emission from “Rhimprom” on the nearest plots of land where

people had been growing

fruits and vegetables.

The analyses data show that vegetables

and dill) contain from 118 to 812 ppq of dioxins and dibenzofkns

(tomato,

cabbage,

(TEQ). Since 1994 a program of dioxin

detection in animal food has been carried out. In 1996 some foodstuffs

were bought at various shops in Ufa:

1706

Table 6 The mean PCDDslPCDFs

content in food from the Republic of Bashkortostan

I

Food

I

I

Food

Content of PCDDslPCDFs

Content of PCDDs/PCDFs

weight basis

lipid basis

(TEQ), ppt

lipid basis

weight basis

Fish

9.20

0.26

Vegetable oil

Chicken

1.54

0.22

Whole milk

0.28

0.02

Chicken fat

Packed milk

3.32

0.11

Duck fat

1.46 0.80

Goose fat

1.1

0.63

Pork

0.98

0.30

Curds

Beef

0.90

0.12

Hard cheese

Mutton

0.18

Cream

1.14

0.17

Sour cream

1.33

0.29

1.13

0.32

0.09

Mayonnaise

Sausage

1.21

chicken, eggs, freshwater

0.44

0.10

Butter

0.43

and sea fish, beef, pork, mutton, vegetable oil, butter, duck and goose fats, pork

fat, smoked sausage, whole milk from farmers and packed milk, cream, sour cream, curds, hard cheese. The obtained results for some food are given in Table 6. While analyzing foodstuffs

we were interested

the levels of relative contamination Primarily we examined foodstuffs PCDDs/PCDFs Consequently

of food produced of vegetable

at the detectable

level except

countries

questionnaire.

of Europe

the isomer profile of dioxin sources. In foodstuffs in the process

leaves

we failed to find

(0.01-0.02

pg TEQlg).

were obtained from the State Regional The basic results

and North

is consumed with milk and meet. The PCDDs/PCDFs

is due to their formation

fruits. However,

in evaluating the dioxins intake with food. The data on

and from the sociological

industrial

and imported from other countries.

cabbage

with food per head in urban regions of Bashkortostan

close to that of other PCDDs/PCDFs

for unwashed

in urban and rural regions of Bashkortostan

Department

PCDDs/PCDFs

in Bashkortostan

origin: corn, vegetables,

this kind of food was not considered

the food consumption Statistical

not only in the absolute data on the dioxin content but also in

on daily intake

of

are given in Table 7. This quantity is America”.

quantity

of

isomer profile in milk corresponds

to

from Ufa 2,3,7,8-TCDD

of 2,4-D industrial production.

The largest

and 2,3,7,8-TCDF

prevail, what

In milk from Sterlitamak

most of

dioxin Cl6 - Cl8 - isomers are present. The daily intake of dioxins by resident population corresponds

of industrial cities amounts to 139 pg/day (TEQ), this

to 2.3 1 pg/kg for body weight per day (BW = 60 kg). For rural population these figures are 69

pg/day and 1.15 pg/kg for body weight, respectively. regions may be related to the consumption

The decrease

of the PCDDs/PCDFs

intake in rural

of the whole cow milk instead of packed one (the TEQ value of

the whole cow milk is 0.02 pg/g BW) and to the lower consumption

of factory-made

meat products

-

1707 Table 7 The daily intake of PCDDs/PCDFs

Dioxin source

by inhabitants of industrial cities for the Republic of Bashkortostan,

Consumption per head, g/day

TEQ

T

I

Beef

100

0.30

32.0

23.0

Pork

30

0.63

18.9

13.6

Mutton

10

0.12

0.8

Poultry

30

0.35

1.2 10.5

Animal fat

19

0.56

10.6

7.6

Smoked food

25

0.44

11.3

8.1

7.5

Vegetable oil

19

0.18

3.6

2.6

Butter

1.2

0.43

5.5

4.0

Eggs

22

0.03

0.6

0.4

Fish

26

0.26

Milk

4.8 21.2

140

0.21

6.7 29.4

Sour cream

7

0.29

2.0

1.5

Curds

7

0.09

0.6

0.4 0.4

Cream Sour milk food Mayonnaise Cheese

3

0.17

0.5

27

0.10

2.7

1.9

7

0.10

0.7

0.6

7

0.32

2.2

1.6

139

100

Total

sausage and smoked food. The diet of the people in Bashkortostan consumption

both of sea and freshwater

Table 7 illustrates the contribution regions of Bashkortostan.

is also characterised

by comparatively

low

fish.

of food to PCDDs/PCDFs

human exposure for the population

It is obvious, that about 97% of dioxins are consumed

of urban

with food, whereas with

water only 1.0 - 1.5 % (1.5 - 2.0 pg TEQ/day) and with the air - 1.5 - 2.0 % (2.0 - 2.8 pg TEQ/day). The PCDDs/PCDFs

isomer profile of women milk from Ufa and Sterlitamak

profile of food. This testifies to the property of PCDDs/PCDFs food consumption,

But the dioxins concentration

industrial centres have the concentration

also depends

also corresponds

accumulation

to the isomer

in human organisms through

on the place of living. Women living in

of dioxins in breast milk equal to 15-23 ppt (TEQ), whereas in rural

regions this value is 3-10 ppt. Women working at “Khimprom” and “Kaustik” have higher concentrations dioxins. However, this is caused not by food but by dioxin emission of these plants.

of

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as compared

levels in the blood

to controls,

Organohulogen

Compounds 9, 247-250 (1992). 2. A. Schecter and J.J. Ryan, Exposure PCDDs/PCDFs@lanar 3. R.Z. Khamitov

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