Toxic chemical container

Source: Benelux Press


THE PROBLEM

In this present report it is shown that there are few environmental problems in Europe that cannot be traced back to some sort of excessive loading of chemicals. Economic development has been driven to a considerable extent by progress and innovation achieved by the chemical industry. This process has led to the marketing and use in different applications of ever-increasing numbers and quantities of chemical substances. More than 10 million chemical compounds (natural or man-made) have been identified. Of these, about 100 000 are produced commercially (200 to 300 new chemicals enter the market each year) and are potential subjects of concern. Estimates suggest that the current world production of chemicals is about 400 million tonnes (Lönngren, 1992). Many chemicals are applied directly to the environment or are discharged after use. Adequate toxicological and ecotoxicological data have been produced for only a very small fraction of the chemicals, and data on environmental pathways and ecotoxicological effects are even more sparse (see Chapter 17).

From being regarded mainly as a potential risk to humans, chemical impact on the environment became of increasing concern from the 1960s. Before then there was little appreciation of the atmosphere and hydrosphere having limited capacity to assimilate the ever-increasing releases of chemicals. The bioaccumulation of certain chemicals in the food-chain and its consequences for the normal function of ecosystems and for human welfare were not well understood either. Apart from a few early signs of chemical threats to the environment (eg, mercury pollution as evidenced by the Minamata disease in Japan, high levels of mercury in game and fish in Sweden, lake eutrophication, PCB and DDT pollution) it was only relatively recently recognised that chemicals which enter the environment can, in general, cause serious detrimental effects in all environmental compartments and to human health whether they be released through normal operation or as a result of accidents. Accidental discharges of chemicals and their environmental effects are treated in detail in Chapter 30.

The human-generated sources of dangerous chemicals which enter the air are widespread. The smokestacks of factories, power-generating stations, waste incinerators, motor vehicles and smelter discharge emit sulphur dioxide, nitrogen oxides, carbon monoxide, hydrocarbons and other combustion products often contaminated with substances such as heavy metals, dioxins, furans, etc.

In highly industrialised or populated areas, chemicals are often released into waterbodies in exceptionally large volumes through industrial discharge pipes and municipal sewage. Apart from large volumes of chemicals entering the environment in such areas, the environmental danger comes from the fact that these releases contain significant amounts of many types of chemicals which are commercially used.

The release of highly toxic chemicals (often as contaminants in high-volume production chemicals) also causes serious problems. Well known examples for these substances are chlorinated hydrocarbons, heavy metals and hydrocarbons (see Chapter 14). Once a chemical is emitted to the air it is usually deposited with rainwater and snow and eventually ends in runoff into rivers and seas. Another main source of chemicals in the environment is from the agricultural use of pesticides, which contain potentially dangerous chemicals that can leach into groundwater. Some non-degradable (heavy metals) and very slowly degradable substances (PCBs, dioxins) can be transformed into more toxic intermediate compounds (DDE from DDT or methylmercury from mercury). On the other hand, bioaccumulation may take place in the food-chain, which can result in concentrations toxic to biota, especially top predators.

Natural transport from one compartment to the next further accelerates the dispersion of a given substance through the ecosystem (Figure 38.1). This eventually leads to accumulation of a substance and harmful effects in another compartment than that to which it was originally released. Most of the chemical compounds released to the environment are subject to biotic and/or abiotic degradation but some are persistent and therefore accumulate in the environment, leading to long-term exposure of organisms. Depending on the toxicity and persistence of the substance, exposure can lead to disorders, genetic mutation, adverse effects on reproduction, cancer, mortality and adverse effects on the nervous and immune systems. It may also cause effects on ecosystems.

A great variety of environmental perturbations caused by chemicals are considered in this report. In particular, the concentrations, trends and effects of chemicals in three environmental compartments: air, water (fresh and marine) and soil are thoroughly treated in Chapters 4 to 7. The human activities which promote the release of chemicals are described in Chapters 19 to 26, and the resulting loads to air and water with problem chemicals are the subject of Chapter 14. The health aspects and environmental impacts of a selection of chemicals considered to be particularly harmful are treated in Chapters 11 and 17. The environmental problems considered in this chapter of the report which relate to human activities and the emission of chemicals include: climate change, stratospheric ozone depletion, loss of biodiversity, major accidents, tropospheric photochemical oxidants, acidification and eutrophication.

To overcome the specific environmental problems caused by an identified chemical, remedial, preventative or legislative measures are taken in many industrialised countries (for example, controls on heavy metals, CFCs, PCBs, DDT, pentachlorophenol, etc). In the last few years, however, it has been generally recognised that such an approach is not sufficient. There must be an integrated concept which addresses the impact of all chemicals that may cause detrimental effects in the environment. However, such an integrated and systematic risk assessment approach is faced with a number of inherent difficulties, the most important being:

  1. the large number of new and existing chemicals which have to be considered;
  2. frequent lack of data which are needed for comprehensive risk assessment;
  3. the possibility that initially innocuous chemicals may react in the environment and be converted to more toxic compounds and cause unforeseen secondary impacts;
  4. the potential danger of almost any chemical to any kind of organism or ecosystem;
  5. dangerous contaminants as by-products in synthesised chemicals produced in large quantities;
  6. frequent lack of regional and global coordinated control measures; and
  7. time delays between regulatory measures and beneficial effects.
GOALS

The overall goal in chemicals control is to reduce the amount of toxic substances in the environment and the risk of exposure of humans and ecosystems to a level where only negligible risks are to be expected (Figure 38.2).

The aim should be to reduce the concentration of each chemical to this level. To ensure this, the continuous monitoring and testing of each chemical released should be encouraged. When evidence arises of potential negative impacts, the exposure of the target environment has to be reduced by individual initiative and/or legislative measures.

Achievement of this overall goal of chemical risk control typically involves specifying the following subgoals, as proposed in the EC's Fifth Environmental Action ­ Programme (CEC, 1993):

  1. Data collection on new and existing chemicals. This should include:
    1. an effective notification procedure for all new chemicals containing a dossier of information about the chemicals' characteristics, hazards, uses and disposal, as well as a risk assessment;
    2. an inventory of existing chemicals, concentrating on high-volume production chemicals and those substances considered to be most dangerous and in need of strict control; and
    3. improved international coordinated data collection for chemicals.
  2. Classification and labelling: the objective of classification is to identify all the physico-chemical, toxicological and ecotoxicological properties of chemicals. Having identified any hazardous property, the dangerous chemical is then labelled to indicate the hazard in order to protect the user, the general public and the environment, including water, air, soil and living organisms. The label provides the general public and persons at work with easy access to the identity of a dangerous chemical, its hazard and what to do in case of emergency.
  3. Risk assessment: to combine information gathered from the classification procedure and knowledge obtained from research to provide assessment of dose/response effects and exposure to humans or ecosystems. This requires data about the level of exposure, the target populations, the biological, toxicological and ecotoxicological effects of a certain amount of pollutant, the threshold level. With this information the risk is defined and an evaluation made concerning the sustainable use of the substance.
  4. Risk management: this has the overall aim of controlling emissions by banning highly hazardous chemicals, limiting the use of dangerous products, substituting dangerous with less dangerous products, limiting selling of dangerous chemicals to authorised purchasers, as well as informing consumers about hazardous chemicals and their alternatives.

To make these goals operational it is important to realise their interconnectedness (Figure 38.3); tight international cooperation between scientists, environmental managers, policy makers and international organisations is absolutely crucial to improve environmental conditions by reducing the ambient load of chemicals.

STRATEGIES

The potential of chemicals to cause harm to life, health, the environment or property has few limits. Hazard control, therefore, aims to eliminate or reduce the levels of hazardous chemicals that can cause harm to humans or the environment, or that can trigger a fire or an explosion. Industry has gradually developed a risk management approach that takes into account the full life-cycle of chemicals. The manner in which these are handled determines whether their effects are beneficial or harmful. Strategies implemented by regulations, programmes and policies already exist internationally and within the European region (see Box 38A).

Policy coverage

Traditionally, risk containment regulations were restricted to chemical substances classified as dangerous. This changed, however, in the 1970s. In principle, two general strategies are available for addressing the control of chemical risk in the environment: a voluntary collaboration between industries and official institutions, or an approach based on legal obligations of industry. The first strategy has been practised by the UNEP and OECD, and, during its development, the EU legislative chemicals control system, which is detailed below, has drawn upon the programmes and experience gathered by these organisations.

Measures and initiatives from official bodies and industries exist in the following areas:

The UNCED (Rio de Janeiro, 1992) also decided in Chapter 19 of Agenda 21 (UNCED, 1992):

  1. to expand and accelerate international assessment of chemicals;
  2. to harmonise the classification and labelling of chemicals;
  3. to exchange information on toxic chemicals and chemical risks;
  4. to establish risk reduction programmes;
  5. to strengthen the national capabilities and capacities for management of chemicals; and
  6. to prevent the illegal international traffic in toxic and dangerous products.

It was underlined that a successful implementation of these six programme areas is dependent on intensive international work and improved coordination of ongoing international activities, as well as on the identification and application of technical scientific, educational and financial means. Collaboration on chemical safety between UNEP, ILO (International Labour Organisation) and WHO in IPCS (International Programme of Chemical Safety ­ for details see Chapter 17) should form the core for international cooperation on environmentally sound management of chemicals. In this field, Agenda 21 also stressed the need for cooperation between international programmes of IPCS, OECD and the EU (see Box 38A) and other regional and environmental programmes, as well as the involvement of NGOs.

An initiative in the USA has had an important impact on the use of chemicals. Here, companies with nine or more employees have to report on the use and disposal of 313 listed toxic substances. The report has to contain the release of these substances to air, water, or underground wells. This toxic release inventory (TRI) has now become an important source of public information, and introduction of this system has led to a rapid reduction of emission of these substances by one third in three years. Now a process of re-evaluating the TRI has started, since as currently formulated it incorporates only the amount of waste to the environment and not the hazardous material incorporated into the product. Furthermore, the list of toxic substances itself is incomplete. Several European countries (see Chapter 17) have recently adopted a similar approach for reducing chemical risk. Moreover, OECD/IPCS/UNEP/USEPA have initiated the pilot phase of a Pollutant Release Transfer Register based on the TRI.

Chemical control in the EU

The basic legislation on the control of chemicals in the EU is EC Council Directive 67/548/EEC on the labelling, packaging and classification of dangerous substances ­ the first of a growing number of directives aimed at protecting human health and the environment. During the 1970s and early 1980s the Community's chemicals control legislation was basically a 'command and control' approach. This has developed considerably and the EC's Fifth Environmental Action Programme now makes it clear that future legislation should be based on a partnership between regulators, industry and the general public towards the attainment of sustainable development. Thus, the EC Regulation 93/1836/EEC, allowing voluntary participation by companies in a Community eco-management and auditing scheme, will be implemented as from June 1995. It aims to promote environmental performance improvements at industrial sites by committing them to establish environmental policies, programmes and management systems, to undertake environmental audits and supply information to the public. It provides the counterpart for product ecolabelling procedures which were introduced by EC Regulation 92/880/EEC.

Ecolabelling means the labelling with an EU-logo of products which have a reduced environmental impact compared with usual products, and is based on the development of a set of ecological criteria for groups of consumer products considered to raise significant environmental problems (eg, detergents, paper, washing machines, paints and packaging material). For products to qualify for the EU-logo they must comply with a set of specific ecological criteria. These are drafted to take account of the product's environmental impact at all stages of its life-cycle, from raw material through manufacture, distribution, use and final disposal. Currently, five Member States (Denmark, Germany, France, Italy and the UK) have started product life-cycle analysis of paper, detergents, paints, hair sprays, refrigerators and washing machines.

The main elements of chemicals control in the EU are shown in Figure 38.5, which indicates that legislation draws a line between 'existing' and 'new' chemicals. Existing chemicals are those which were on the EC market before 18 September 1981. The Commission made up an inventory listing these substances known as the European Inventory of Existing (commercial) Chemical Substances (EINECS). A chemical substance is 'new' and must be notified if it cannot be found among the 100 116 substances listed in EINECS. Substances in EINECS are exempt from notification, but if they are dangerous they must be classified and labelled by the manufacturer or importer.

Council Directive 92/32/EEC (Seventh Amendment of 67/548/EEC) regulates the testing and notification procedures for any new chemical put on the market in the EU. More than 800 chemicals have been notified by the EU since 1983 based on this system.

With the legal basis for the notification having been harmonised to a large extent within the EU, the chief goal for the years to come is to harmonise the assessment. This is done by the Risk Assessment Directive, 93/67/EEC, which requires an assessment of the chemical risks to humans/environment to be carried out, and establishes a 'Technical Guidance Document' which assists member countries to implement the environmental risk assessment of notified chemicals.

In contrast to these 'new' chemicals, many of the more than 100 000 chemicals in the EINECS inventory have never been tested for their effects on human health and the environment. To set up a long-term strategy to tackle this problem the EU adopted Council Regulation 93/793/EEC designed to identify and lead to the control of risks from some of the existing chemicals. According to this programme the main goal is the collection of basic information about existing chemicals, including their uses and characteristics, environmental fate and pathways, toxicity and ecotoxicity. This is to be reached through a three-step approach:

  1. The initial phase (June 1993­June 1994) included the assessment of approximately 1800 chemicals produced or imported in amounts above 1000 tonnes per year. Fewer data are required for chemicals manufactured or imported in quantities between 100 and 1000 tonnes per year.
  2. Phase two, beginning in 1994, aims to publish at regular intervals a priority list of substances 'requiring immediate attention because of their potential effects on human health and the environment' involving a cooperative procedure among the Member States. Special attention will be given to substances having chronic effects, those toxic to reproduction, and mutagens.
  3. The third step includes risk assessment and the development of a control strategy. The priority chemicals will be divided up among Member States in order to perform individual risk assessment. The country acting as rapporteur for a particular chemical is able to ask for additional information from industry or from the importer before preparing the risk assessment. Based on this work, the rapporteur will propose and report a control strategy. The European Commission will make sure that the individual reports are comparable before final publication. On the basis of these reports the European Commission may propose restrictions on the use of the chemicals.

A further step in a chemical risk control strategy is to strengthen environmental research with the aim of improving, among other things: the understanding of the multitude of processes whereby chemicals are distributed in the different environmental compartments, their fate once there, how they affect the structure and functioning of ecosystems, the search for ways to prevent pollution effects, to restore damaged ecosystems, and to develop safer industrial and agricultural production processes. Equally important is research into the development of computer software for assessing the toxic properties of chemicals and for making maximum use of current information in mathematical models (eg, QSAR techniques; see Chapter 17) simulating environmental dispersion, fate and consequences of chemicals.