§ Mr. William RossTo ask the Secretary of State for Northern Ireland if he will publish his Department's assessment of the dangers to health if chlorobutadine is inhaled or absorbed through the skin.
§ Mr. HanleyDanger to health from chlorobutadine depend on concentration and exposure time. At the levels encountered in industry it is of low toxicity. Exposure to the high levels can result in skin, eye and lung irritation and generalised toxic systemic effects. Gross overexposure, as in the case of many chemicals, can lead to fatalities. It should therefore be handled with care and in accordance with the manufacturer's instructions.
§ Mr. William RossTo ask the Secretary of State for Northern Ireland what is the chemical formula of the residues of the chlorobutadine spillage in the drainage system of the Du Pont site at Maydown, County Londonderry, and Lough Foyle; what effect such residues have on the environment; and whether they exceed environmental protection standards.
§ Mr. AtkinsThe chemical formula of the compound is 2-chloro-1, 3-butadiene (C4 H5 C1) (Chemical Abstract Service (CAS) No. 31900–55–7).
604WThe levels detected in samples collected in the week beginning 12 October 1992 were at or below the analytical detection limit. At such low levels it is considered that there has been no adverse effect, given that chlorobutadine is not known to bioaccumulate.
The median tolerance limit (TLM96) for the compound is 234 milligrammes/litre—the test species is the blue gill sunfish. This is the concentration at which 50 per cent. of the test species survive. Levels detected in samples were of the order of 10,000 times lower than this value.
§ Mr. William RossTo ask the Secretary of State for Northern Ireland when the warning equipment first denoted a fault in regard to the spillage of chlorobutadine at the Du Pont factory at Maydown, County Londonderry; what action was taken then; when the spillage was sealed off; when his Department was notified; and what steps he has taken to determine the extent of the damage and dangers to workers and persons resident near the plant and the environment.
§ Mr. AtkinsThe Department has been advised by Du Pont that the warning equipment at the Maydown factory first signalled a fault in the early hours on Tuesday 6 October 1992. This signal was misinterpreted by an employee as having been caused by fumes from a vat containing chlorobutadine which had been cleaned out. At 7 am it was discovered that a pump had failed and was allowing chlorobutadine to escape to the waste stream to Lough Foyle. A second alarm failed to go off because it was blocked by the substance.
The processing was stopped at once but Du Pont has advised the Department that it did not at first appreciate the scale of the spillage. It was not until further analysis had been made of the routine samples from the waste stream and the recovery system had been checked that it was realised on Thursday afternoon, 8 October, that some two to three tonnes could have been spilled.
The Department of the Environment was first advised by Du Pont of the spillage before lunchtime on Friday 9 October.
Arrangements were made at once to take water and shellfish samples from Lough Foyle and the Department of Health and Social Services (DHSS) immediately issued a warning against consuming fish or shellfish from the Foyle system. Subsequent analysis of the samples showed an increase in normal background levels, but samples taken later showed that the levels had fallen, with most slightly above or at the level of detection. On 14 October, DHSS withdrew the advice against eating fish and shellfish.
The Department of the Environment considers that the spillage has not resulted in any significant damage to water quality or aquatic life in Lough Foyle. Arrangements will be made for long-term monitoring but it is unlikely that any persistent effects will be found, as chlorobutadine is not known to bioaccumulate. The health and safety inspectorate of the Department of Economic Development has been inspecting the chemical plant to avoid a recurrence of this type of incident.
§ Mr. William RossTo ask the Secretary of State for Northern Ireland what are the exposure limits to the vapours of chlorobutadine; and whether those limits were exceeded in the recent spillage of chlorobutadine at the Du Pont factory at Maydown, County Londonderry.
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§ Mr. AtkinsExposure limits to vapours of chlorobutadine have been assigned in United Kingdom and in the United States at 10 parts per million over an eight-hour working day/40-hour week. There is no evidence to suggest that these limits were exceeded.
§ Mr. William RossTo ask the Secretary of State for Northern Ireland whether the storage of chlorobutadine is covered by the regulations set out in Statutory Rules of Northern Ireland 1992 No. 401.
§ Mr. AtkinsNo. These regulations—the Pollution of Waters by Dangerous Substances (Amendment) Regulations (Northern Ireland) 1992—do not relate to storage. They implement the requirements of a series of European Community directives on pollution caused by dangerous substances discharged into the aquatic environment. Chlorobutadine is not one of these substances.
§ Mr. William RossTo ask the Secretary of State for Northern Ireland if he will publish his Department's assessment of the dangers to human health and to the environment of chlorobutadine and the adequacy of a long-term exposure limit of 10 parts per million for this substance.
§ Mr. HanleyThe Department believes that the normal use of chlorobutadine within industry does not pose a significant risk to human health or to the environment. In terms of occupational exposure, the internationally accepted standard concentration in the air of 10 parts per million, calculated on the basis of an eight-hour day over a working lifetime, is considered to be safe.
§ Mr. William RossTo ask the Secretary of State for Northern Ireland if he will make a statement on the inspection carried out by his Department of the spill of chlorobutadine at the Du Pont site at Maydown, County Londonderry.
§ Mr. AtkinsMy Department's officials have inspected the neoprene plant at Du Pont and have had discussions with the company's staff. The company has reviewed its alarm systems and has instructed its staff, if there is any suspicion whatsoever of a spillage, to stop processing immediately and divert the waste stream to an emergency holding facility.
§ Mr. William RossTo ask the Secretary of State for Northern Ireland what assessment he has made of whether the storage and transport of dangerous substances at the Du Pont site at Londonderry meet the standards set out in current regulations.
§ Mr. AtkinsThe health and safety inspectorate of the Department of Economic Development inspects this plant606W regularly and is satisfied that the storage and transport of chlorobutadine meet the requirements of the current health and safety legislation.
§ Mr. William RossTo ask the Secretary of State for Northern Ireland what surveys he has carried out to discover how many persons or animals suffered or appeared to suffer discomfort as a result of the spillage of chlorobutadine at Du Pont's site at Maydown, County Londonderry, in early October.
§ Mr. HanleyNo specific public health surveys have been carried out. However, the Western health and social services board was alerted to the spillage and the incident was widely publicised throughout Northern Ireland. To date, there have been no reports of discomfort or illness to humans or animals as a result of the incident.
§ Mr. William RossTo ask the Secretary of State for Northern Ireland what assessment he has made of whether the precautions taken against static discharges of dangerous substances at the Du Pont site at Maydown, County Londonderry are adequate.
§ Mr. AtkinsDu Pont has a consent from the Department of the Environment for Northern Ireland DOE NI) under section 7 of the Water Act (NI) 1972 to discharge its trade effluent to Lough Foyle. All the effluent from the factory is discharged through a single outfall.
Prior to the recent incident, DOE (NI) had been reviewing the Du Pont discharge consent and was on the point of finalising new tighter consent conditions. Du Pont is an environmentally responsible company and has consistently complied with the consent conditions. Improvements over the years in the factory processes have made it possible to impose more stringent discharge standards.
§ Mr. William RossTo ask the Secretary of State for Northern Ireland what assessment he has made of whether the storage and transport of dangerous substances at the Du Pont site at Maydown, County Londonderry, presently meet the standards set out in the Environmental Protection Act 1990.
§ Mr. AtkinsThe provisions of the Environmental Protection Act 1990 have not yet been extended to Northern Ireland. The storage and transport of dangerous substances at the Du Pont site meet the standards applicable under current legislation.