by Mr. Lansana Conté

CONTENTS

B) PROBLEMS OF MANAGEMENT OF PCBs IN GUINEA

BACKGROUND

Polychlorinated biphenyls, or PCBs, were generally put on the market in the 1930s, because of their remarkable technical, physical and chemical properties. They were manufactured under various commercial brand names:

* Pyralene

* Clophen

* Aroclor

* Apirolio

Since 1966, it has become apparent that these substances are only marginally biodegradable and have a strong tendency to be accumulated by living organisms along food chains. Several studies have shown the presence of PCBs in maternal milk. To this environmental phenomenon there has recently been added the discovery that PCBs can, in cases of fire, give rise to products that are suspected to be highly toxic. The economic consequences of accidents such as that of Binghampton in the United States or that of Reims in France have shown the urgency of reviewing the situation.

This is why, in consideration of the risks that PCBs may pose for man and for the environment and considering that restrictions in its use introduced in the 1970s have not entailed any noticeable decrease in pollution by these substances, the European directive 85/467/DEE dated 1 October 1985 banned, as from 1 July 1986, the sale and use of new equipment containing PCBs. The use of equipment in service at that date is authorized up to the time of their disposal or the end of their working life. The sale of second-hand equipment of this kind is banned.

It seems therefore to be important that we stress preventive methods to be implemented during the use and at the time of withdrawal of existing installations, together with their replacement.

CHARACTERISTICS

Commercial PCBs are mixes of isomers formed by two benzenic cycles substituted by atoms of chlorine that are variable in number. The main impurities indicated are polychloronaphtalene and polychlorodibenzofurans. They are presented in the form of a viscous liquid, colourless or pale yellow, with low vapour pressure. Their solubility in water is extremely low; they are however soluble in mineral oil and in most organic solvents. PCBs are characterised by their excellent dielectric qualities, their high chemical inertia, their non-inflammability and their thermal stability (up to 300^oC).

USE

PCBs can be used as dielectric insulators, grouped under the generic name of "askarels" as follows:

RISKS POSED BY THE USE OF PCBs

Electric equipment containing PCBs do not pose any danger of exposure to PCBs in normal operating conditions. However, they are liable to cause accidents, which can be divided into three categories:

CHEMICAL RISKS

TOXICITY OF PCBs

The specific effects of PCBs are difficult to distinguish because of the possible presence in them of impurities that are more toxic such as polychlorodibenzofurans (PCDF), the polychlorodibenzodioxins (PCDD), polychlorinated biphenylenes (PCBP), polychloropyrenes.

Their acute toxicity is very low. Their sub-acute and chronic toxicity is shown basically by chloracne, which is the main symptom appearing in workers that have been exposed to the chemical. Eczematiformes rashes may also result, as well as liver problems (enlarged liver, ASAT and ALAT amino acid transfers) and, occasionally, arterial hypertension.

TOXICITY OF THERMAL DECOMPOSITION PRODUCTS OF PCBs

Hydrogen chloride, which is the main risk factor, is a vapour that is corrosive for ocular respiratory and digestive mucous. In high concentrations it can cause bronchial spasm and pulmonary oedema.

WASTES CONTAINING PCBs

Wastes include:

• Polluted soil and building wastes;

• Liquids and rinse water

DIAGRAM

B. PROBLEMS OF MANAGEMENT OF PCBs IN GUINEA

However, in the context of addressing these problems of the environmental management of PCBs, the following efforts should be mentioned:

• The Ministry of Supply, through the National Environmental Office (FISC National Focal Point) has initiated a campaign to identify PCB sources and to evaluate efforts for the sound management of PCBs for the following mining companies:

(a) The Guinean Bauxite Company (CBG), a company which combines the mining and marketing of bauxite;

(b) FRIGUIA, a company that produces aluminium from bauxite. Its annual production ranges between 600,000 and 800,000 tons.

This programme was in connection with the installation of transformers of the electricity network of Kamsar and Sangaredi for which the dielectrics available at the time were pyralene oils.

In 1996, this replacement programme for transformers using PCBs was initiated. Between now and the year 2000, the CBG power division envisages the complete replacement of all transformers using PCBs. The replacement dielectrics to be used are: BP oil or UGILECT T

Disposal consists in storing scrapped transformers and other polluted materials (for example, polluted soil) and liquids to PECTREDI Treatment Centre, TREDI SAINT-VUL-BAS: Z.I. DE PLAINE DE L'AIN-BP 55 SAINT-VUL-BAS-01150 LAGNIEU, Tel: 74615355, Fax: 76 61 522 44 - FRANCE.

Since 1987, CBG has exported 108 tons of pyralene wastes to PECTREDI. For the storage of PCBs, CBG has installed a rehabilitation and storage workshop. The technique of upgrading transformers using PCBs in good condition is called "RETROFILLING", or fluid substitution. This technique consists of the draining of fluids based on PCBs, followed by decontamination down to 50 ppm and then filling the transformer with another dielectric. The stock of PCBs held by CBG, calculated in 1996, was 30,081 kg weight of dielectric.

At the time of the installation of transformers in the electricity network of Fria, the available dielectrics were pyralene oils. But after the discovery of the risks posed by pyralenes for man and the environment, Friguia established a replacement plan.

The large number of transformers (more than 100 in the factory) justified some delay in replacing all PCBs. Of the 1005 transformers presently used, 46 no longer use pyralene (i.e. 44%).

In the immediate future, Friguia envisages the following measures:

PCBs are used in transformers, auto-transformers and self-starters in the factory and in towns. An inventory made in January 1995 gave the status as follows:

The disposal of PCBs in FRIGUIA consists in the recovery of pyralene dielectrics, and storing them before transporting them to a specialized disposal centre.

Arrangements were made with PECTREDI regarding this issue. FRIGUIA, in its initial campaign, collected 55 drums of pyralene and 10 drums of contaminated soil which are awaiting dispatch to PECTREDI. They are stored in containers, thus avoiding any kind of pollution.

IDENTIFICATION OF THE PROBLEMS POSED BY POPs
QUESTIONNAIRE FOR PARTICIPANTS

Name of country: GUINEA

Name of substances:

Name of substances:

27. Are POPs exported from your country? x yes ¨ no ¨ don't know

Are POPs used in your country? x yes ¨ no ¨ don't know

Name of substances: PCB Approximate quantity: not estimated

Are chemical or non-chemical alternatives available?

YES

Have alternatives been chosen? ¨ after ¨ occasionally ¨seldom ¨never

Reasons why they have not been chosen ¨cost ¨effectiveness ¨other

Difficult technology

Name of substances: BP oil and UGILECT Approx. quantity: Not estimated

Are chemical or non-chemical alternatives available?

Yes, for PCBs

Have alternatives been chosen? x after ¨ occasionally ¨ seldom ¨never

Reasons why they have not been chosen: ¨cost ¨effectiveness ¨other

Name of substances: Approx. quantity:

Are chemical or non-chemical alternatives available?

Have alternatives been chosen? ¨after ¨occasionally ¨seldom ¨never

Reasons why they have not been chosen: ¨cost ¨effectiveness ¨other

Name of substances: Approx. quantity:

Are chemical or non-chemical alternatives available?

Have alternatives been chosen? ¨ after ¨ occasionally ¨ seldom ¨never

Reasons why they have not been chosen: ¨ cost ¨ effectiveness ¨other

28. Are POPs stored in your country? ¨ yes ¨ no ¨ don't know

Please specify if the product is stored as a product, recyclable material or wastes:

Substance PCB Quantity: Partially As: Dielectric

Are the storage areas known? x yes ¨ no

29. Are POPs released into the environment? ¨ yes ¨ no ¨ don't know

If so, what ways are they released?

Released into: ¨ water ¨ air ¨ ground

Origin of release:

¨ industrial activity

¨ crop treatment

¨ vector control

¨    others

30. Are people exposed to POPs? ¨ yes ¨ no x don't know

If so, how?

¨ professional exposure     ¨ consumer exposure

¨ residential area exposure     ¨ accidents and poisoning

31. What kind of monitoring takes place in your country?

¨ ambient/air ¨ surface water ¨ groundwater

¨ emission sources ¨ biological

Brief description:

32. Are there legal restrictions on the use of POPs? ¨ yes x no ¨don't know

What kinds of action have been adopted to control the use, production or importation of POPs?

¨ Health standards or regulations ¨ optional programme

¨ Environmental standards or regulations

¨ Directives

¨ Other: Preventive measures, risks to humans and the environment arise from two mining operations, namely, the replacement of transformers using PCBs and safety during their use and PCB waste disposal in a specialized centre in France