Towards a Safe and Sustainable Materials Sector

Reg GreenICEM

ICEM World Conference for the Materials SectorBrussels, 17-18 November 2005

The Industries

The Materials sector of the ICEM covers a number of industries including:

THE GLASS INDUSTRYTHE CERAMICS INDUSTRYTHE CEMENT INDUSTRY

ALTERNATIVE FUELS(ASBESTOS)

The Glass Industry

• Chromium, cobalt, cadmium, manganese, nickel and selenium used as colouring agents.

• Lead (also an issue in the ceramic sector)• Sulphuric and hydrochloric acids. • Polycyclic aromatic hydrocarbons (from fumes

generated by oil-fired furnaces and from mineral oils used for lubricating moulds).

The Glass Industry hazards

• Salts of chromium, cobalt, cadmium, manganese, nickel and selenium are used as colouring agents. Chromium, for instance, is a well known irritant and cause of lung cancer. One study has shown that the death rate from lung cancer for exposed workers is 29 times that for average members of the population

• Arsenic and antimony salts are employed to remove bubbles from molten glass. Exposure to fumes or dusts of pure arsenic or its compounds causes chronic poisoning. These fumes and dusts can cause rashes and darkening of the skin, and can irritate the nose, leading to nosebleeds and perforation of the inner nose. Eye irritation can lead to corneal damage. Dust and fume exposure can lead to lung cancers which may appear 20 years or more after exposure.

• Industrial poisoning from antimony is not a clear-cut illness because workers are exposed simultaneously to arsenic, which is present as an impurity of antimony. Most studies of antimony toxicity are of acute poisoning, and different levels of toxicity are found in industries where exposure levels vary.

• Calcium fluoride may be added to accelerate melting. It can be fatal if inhaled or ingested. In the industrial context it is more likely to cause chronic illness. Its irritating properties can cause bronchitis, chemical pneumonia, and even pulmonary oedema or excessive accumulation of fluids in the lung. Repeated exposure to low doses leads to increased deposition of fluorides in the bones and ligaments. This condition called fluorosis, has no symptoms at first, but the bones and teeth become dense – something that shows up on x-rays. Continued exposure can lead to brittle bones, spontaneous fractures, and deposits that can cause painful arthritis.

• Barium salts may be used to increase electrical resistivity and optical refractivity. The primary health effect of exposure to barium in industry is baritosis, which results from dust trapped in the lungs. More serious reactions may occur from exposures to fine dusts of barium compounds during grinding operations. These compounds stimulate all the muscles and nerves, causing muscle spasms, and pain. The blood vessels also narrow and heart beats irregularly. It may beat so rapidly that it can no longer pump effectively.

• Thorium and rare earth metals such as lanthanum may be used to improve optical properties and these are all industrial irritants.

• Lead (represents about 30% in the production of heavy crystal glass, and 10% in semi-crystal glass) and is an important source of occupational exposure within the materials sector. Inorganic lead is a well established poison. The first symptoms of exposure to inorganic lead poisoning are inability to sleep, fatigue and constipation. If severe exposure is continued, anaemia, colic, and neuritis will develop. The colic may be so painful that it has on occasion been misdiagnosed as appendicitis. Lead affects the blood-forming tissues in the bone marrow, producing anaemia. All lead workers should be given regular blood examinations to check for blood disease. After many years of exposure, a person may develop kidney complications that lead to high blood pressure and even to complete kidney failure.

• Sulphuric and hydrochloric acids is used for chemical polishing and matting of glass surfaces. Sulphuric acid is quite volatile when concentrated and gives off sulphur trioxide gas and sulphuric acid mist, both strongly irritating to the respiratory tract. In fact sulphur trioxide has asphyxiating properties. In solution, sulphuric acid is corrosive to the skin and teeth. Lung scarring (pulmonary fibrosis) and emphysema may follow acute reactions. Chronic effects of long-term exposure are not known

• Hydrochloric acid has a detectable odour at the threshold limit. It is highly corrosive in solution, and the vapour is extremely irritating to all parts of the respiratory tract. It is usually so irritating to the upper air passages that people leave the vicinity to avoid further exposure. However, severe lung damage (pulmonary edema) may result from short high-level exposures. Prolonged exposure to moderately high concentrations of the gas can cause tooth erosion, ulcers of the mouth, skin, and gums, and perforation of the nasal septum (the cartilage separating the nostrils.

• Polycyclic aromatic hydrocarbons result from fumes generated by oil-fired furnaces and from mineral oils used for lubricating moulds. Aromatic hydrocarbons are compounds derived from benzene (benzol). Many of them have similar effects on the body but they vary greatly in toxicity. All the liquids in this group are irritants and can cause dermatitis after prolonged skin contact. The vapours are irritating, and inhalation can lead to damage to other organs. Although, as their name implies, the aromatics have distinctive odours, the nose soon loses the ability to discern them, so that their smell cannot be relied upon as a warning against excessive exposure.

• Asbestos in the past, asbestos was used as a thermo-insulator in hot structures, as well as in protective clothing). In some countries this may still be the case. The dangers of asbestos are now very well documented and the number of workers who have died been disabled and continue to suffer form exposure are legion.

The hazards:

• ASBESTOSIS this is a disabling and usually fatal scarring of the lungs; the main symptom is a shortness of breath, which gets progressively worse as more of the lung becomes scarred and useless

• LUNG CANCER painful and often fatal; workers who are exposed to asbestos and who also smoke face a much, much higher risk of lung cancer than other exposed workers

• MESOTHELIOMA a rapidly fatal and painful cancer of the lining of the lung or stomach nearly always due to asbestos exposure. This disease is killing more relatively young workers

• OTHER CANCERS asbestos has been linked to many other cancer types, particularly cancer of the larynx

• There is no cure for either mesothelioma or asbestosis. The victims usually feel no ill effects until they suddenly find themselves short of breath. The worst affected waste away and eventually die in an agonising choking spasm.

The Ceramics Industry

• Paints and varnishes (glycol ethers and solvents). The solvents contained in such products are quickly absorbed via the bloodstream.

• Silica. Inhaling the free, finely divided dusts of silicon dioxide causes a form of pneumoconiosis called silicosis.

• Lead (used in certain glazes).

• Heat (there are a number of aspects to consider):Heat strokeHeat exhaustion, heat fainting or “heat syncopeHeat shock Heat fatigue

The Ceramics Industry hazards

The more well known hazards to which workers in the Ceramics Industry are exposed include:

• Paints and varnishes (glycol ethers and solvents). The solvents contained in such products are quickly absorbed via the bloodstream. Once in the body, solvents are quickly absorbed via the bloodstream. They are then deposited in the fatty tissues surrounding different organs and released from there with potentially toxic effects on the organs themselves. Solvents can cause both short term (acute) and long term (chronic) effects on the body. A very serious health effect of many solvents is their anaesthetic effect - that is they make those exposed feel sleepy. With increasing exposure, solvents induce dizziness, drowsiness, feelings of intoxication, and nausea. If exposure continues unconsciousness will follow and possibly death. It is well known that those exposed to solvents can develop solvent dependency.

Skin contact may result in eczema or dermatitis, since solvents dissolve even the skin’s own fatty substances.

Long term effects result from frequent exposure over a long period, often involving smaller quantities than are needed to produce obvious effects in the short term. In the long term, certain solvents can have a toxic effect on just about every organ of the body.

• Silica. Inhaling the free, finely divided dusts of silicon dioxide causes a form of pneumoconiosis called silicosis. I will not dwell on silica in this presentation as following speakers will be speaking about it.

Inhaling the free, finely divided dusts of silicon dioxide causes a form of pneumoconiosis called silicosis. The smaller and more compact crystalline forms (quartz, tridymite) cause the greater lung scarring since they have the most dangerous particle size: 0.05 microns - 5 microns.

Silicosis may develop either rapidly or slowly. In rapid developing or acute silicosis, symptoms may appear as soon as 8 to 18 months after the first exposure. The course of slowly progressive or chronic silicosis is very similar to that of acute silicosis except that it arises after many years of exposure and may take many more years to become worse.

The physiological effect of exposure to silica dust is that there is lung scarring which results in shortness of breath and, if progressive, can lead to massive fibrosis - itself frequently accompanied by increased susceptibility to tuberculosis and other infections. Finally, the heart, which must pump blood through the stiff, inelastic lungs, becomes weakened and enlarged and fails to pump effectively.

• Lead (used in certain glazes). I have already addressed in the context of the glass industry, the principle hazards of lead.

Inorganic lead such as that usually found in lead or in grinding operations is a well established poison. The first symptoms of exposure to inorganic lead poisoning are inability to sleep, fatigue and constipation. If severe exposure is continued, anaemia, colic, and neuritis will develop. The colic may be so painful that it has been misdiagnosed as appendicitis. Lead affects the blood-forming tissues in the bone marrow, producing anaemia. All lead workers should be given regular blood examinations to check for blood disease. After many years of poisoning, a person may develop kidney complications that lead to high blood pressure and even to complete kidney failure.

• Heat (there are a number of aspects to consider):

Heat stroke - Heat stroke is characterised by a sharp rise in body temperature, confusion, angry behaviour, delirium, and even convulsions. There is no sweating and the skin is warm and dry. Unacclimatised workers who are moderately active in a hot environment can get heat stroke. It is more likely to happen to people who are older, who have pre-existing heart or circulatory disease, who are overweight, or begin with slight dehydration - as does a person who has had a lot of alcohol to drink.

Heat exhaustion, heat fainting - Heat exhaustion, heat fainting or “heat syncope”, is the mildest form of heat exhaustion. It can happen without any elevation of the body temperature and with only moderate heat exposure. People who are not used to heat, or who may be physically unfit as well, develop heat fainting.

Heat shock - Heat shock is a common form of heat exhaustion that occurs in healthy persons working in hot climates to which they are partially or totally unaccustomed, or unacclimatised. This reaction takes place when the body loses an excessive amount of fluid or salt because of insufficient sweating and inadequate fluid replacement. As a result of this loss, there is not enough fluid in the body to maintain circulation to all the organs.

Heat fatigue - Heat fatigue is less well defined by scientists than heat exhaustion or heat stroke. It is probably also the most common of the three disorders. It is the emotional reaction to a hot environment. A person with heat fatigue does not work as well, produces less, makes more mistakes, and has more accidents. The problem is worse if the fatigue is not relieved by rest.

The Cement Industry

• Dusts produced during the drilling and crushing. During the cement processing, the main hazard is dust.

• Explosions.• Road transport accidents• High ambient temperatures• High noise levels (120 dB) in the vicinity of ball

mills. • Diseases of the respiratory system, digestive

disorders, skin diseases, rheumatic and nervous conditions, hearing and visual disorders

• Wide variations in macro-climatic and micro-climatic conditions

Cement Industry hazards

The cement industry has a number of hazards including

In the quarries from which the clay, limestone and gypsum for cement are extracted, workers are exposed to the hazards of climactic conditions, dusts produced during the drilling and crushing, explosions and falls of rock and earth. Road transport accidents occur during haulage to the cement works.

• During the cement processing, the main hazard is dust. Dust levels may vary tremendously, depending on the nature of the plant and management attitudes to safety, In modern factories using the wet process, one would expect dust levels of no more than 15-20 mg/m3 of dust as maximum upper short term values. But in the past and in older plants with less attention paid to dust control, dust levels are frequently very much higher.

• In the quarries from which the clay, limestone and gypsum for cement are extracted, workers are exposed to the hazards of climactic conditions, dusts produced during the drilling and crushing, explosions and falls of rock and earth. Road transport accidents occur during haulage to the cement works.

• Other hazards encountered in cement works include high ambient temperatures, especially near furnace doors and on furnace platforms, and radiant heat and high noise levels (120 dB) in the vicinity of the ball mills. Carbon monoxide concentrations ranging from trace quantities up to 50 ppm have been found near limestone kilns.

• Pathological conditions encountered in cement industry workers include diseases of the respiratory system, digestive disorders, skin diseases, rheumatic and nervous conditions, hearing and visual disorders. Chronic bronchitis, often associated with emphysema, has been reported as the most frequent respiratory disease.

Normal Portland cement is not generally considered to cause silicosis because of the absence of free silica. However, workers engaged in cement production may be exposed to raw materials which present great variations in free silica content. Acid-resistant cement, used for refractory plates, bricks and dust contain high amounts of free silica and exposure to them involves a definite risk of silicosis. Some cases of severe pneumoconiosis have been found - most likely as a result of exposure to materials other than clay and Portland cement.

Skin diseases amongst cement workers have been said to account for about 25% or more of all the occupational skin diseases. Various forms have been observed. As early as 1947 it was suggested that 'cement eczema' might be due to the presence in the cement of hexavalent chromium. Although the raw materials used for cement do not usually contain chromium, possible sources of the chromium in cement include:

• volcanic rock (tuff)• the abrasion of the refractory lining of the cement kiln• the steel balls used in the grinding mills• different tools used for crushing and grinding the raw materials and the

clinker

High noise levels (120 dB) in the vicinity of ball mills can be a major hearing hazard. The loudness of sound is measured in units called decibels. For example, normal conversation is approximately 60 decibels, the humming of a refrigerator is 40 decibels, and city traffic noise can be 80 decibels.

Examples of sources of loud noises that cause noise-induced hearing loss (NIHL) are motorcycles, firecrackers, and firearms, all emitting sounds from 120 to 140 decibels. Sounds of less than 80 decibels, even after long exposure, are unlikely to cause hearing loss.

The wide variations in macro-climatic and micro-climatic conditions found in the cement industry are thought to favour the appearance of various disorders of the locomotor system (arthritis, rheumatism, spondylitis and various muscular pains) and the peripheral and nervous system (back pain, neuralgia, radiculitis of the sciatic nerves).

Hierarchy of controls (1)

• Technical risk control measures• Procedural risk control

measures• Behavioural risk control

measures

Hierarchy 1: Technical, procedural and behavioural

The first hierarchy I want to address is what is often called the technical, procedural and behavioural hierarchy, which has three categories:

● Technical risk control measures. These include machinery guarding, various forms of fencing, and the different types of ventilation. In general, these types of risk control measure can be designed and installed so that they have the minimum reliance on people doing what they are supposed to do.

● Procedural risk control measures. These include systems of work and the maintenance of plant, equipment, etc, in a safe condition. Where the procedures are well designed and their implementation effectively monitored, these risk control measures can be successful but they do rely on, for example, people keeping to work procedures and remembering – and being allowed - to carry out the necessary maintenance work.

● Behavioural risk control measures. These include information and training; measures that rely for their effectiveness on a number of things, including the appropriateness of the information or training, the extent to which it is understood, and the extent to which this understanding is put into practice.

Hierarchy of controls (2)

• Eliminate hazard at source • Reduce hazard at source • Remove person from hazard • Contain hazard by enclosure • Reduce employee exposure • Personal protective equipment

Hierarchy 2: From elimination to personal protective equipment

This hierarchy typically has six categories and they are listed here in order of importance, with the last being the least desirable and only to be used when other methods have been considered.

• Eliminate hazard at source, eg Using a non-hazardous substance instead of a hazardous one; not using a

noisy machine

• Reduce hazard at source, eg Using a substance less hazardous than the one used at present; replacing

a noisy machine with a quieter one

• Remove person from hazard, eg Undertaking all paint spraying by unattended robots; not allowing people

to work near noisy machines

• Contain hazard by enclosure, eg Undertaking all painting in a proper, enclosed painting bay; put

soundproofing round noisy machine

• Reduce employee exposure, eg Organising work such that, for instance, four people are exposed

for two hours each, rather than one person for eight hours. This applies in particular to exposure to substances or noise

• Personal protective equipment (PPE), eg Use of gloves, goggles and breathing apparatus for substances

and ear defenders for noise

Hierarchy of controls -A summary

• Eliminate risks • Combat risks • Minimise risk

The following is a summary of the preferred hierarchy of risk control principles:

• Eliminate risks by substituting the dangerous by the inherently less dangerous, eg:

Use less hazardous substances; substituting a type of machine which is better guarded to make the same product; avoiding the use of certain processes.

• Combat risks at source by engineering controls and giving collective protective measures priority, eg:

Separate the operator from the risk of exposure to a known hazardous substance by enclosing the process; protect the dangerous parts of a machine by guarding; design process machinery and work activities to minimise the release of, suppress or contain, airborne hazards; design machinery which is remotely operated and to which materials are fed automatically, thereby separating the operator from danger areas.

• Minimise risks, eg:

Designing suitable systems of work; using personal protective clothing and equipment – this should be only be used as a last resort.

The hierarchy reflects the fact that eliminating and controlling risk by using physical engineering controls and safeguards is more reliable than relying solely on people.

Alternative Kiln Fuels

• In certain circumstances the industrial waste used as cement kiln fuel can give rise to the production of dioxins and furans - two of the most toxic groups of chemicals known (especially when chemicals are incinerated at temperatures which do not ensure complete combustion)

• possibility of exposure of cement kiln operators to unknown chemical mixtures (i.e. of whose composition they know nothing and in whose handling they are wholly untrained).

A more recent occupational health and safety concern - as well as a high profile environmental issue, is the use of cement kilns for the burning of what would otherwise be industrial waste.

Such industrial waste is often referred to as 'alternative fuel', a term, which disguises some of its less palatable aspects. In some circumstances the industrial waste used as cement kiln fuel can give rise to the production of dioxins and furans - two of the most toxic groups of chemicals known. This is especially likely when certain chemicals are incinerated at temperatures which do not ensure complete combustion. In specialist incinerators, there are normally very stringent regulations governing the burning of such chemicals. However, the same chemicals burned in cement kilns may not be subject to such strict controls.

In addition, the 'alternative fuel' - better described as unwanted and often highly toxic chemical mixtures - has to be received by the kiln operator and subsequently introduced into the kiln. This gives rise to the obvious possibility of exposure of cement kiln operators to a chemical mixture of whose composition they know nothing and in whose handling they are wholly untrained. Given the high costs of 'normal' fuel and the energy intensive nature of cement kilns, there is an increasing tendency for kiln operators to turn to the 'alternative fuels' as a cheaper option.

ICEM Global Agreements

At the moment the ICEM has a global agreement with only one company in the materials sector; this is Lafarge. This particular global agreement has been signed with Lafarge jointly with the ICEM and the International Federation of Building and Woodworkers (IFBWW).

There is clearly scope for more such global agreements and the ICEM would welcome hearing from affiliates about any companies with whom they enjoy decent relations which could be the basis for exploratory discussions about additional global agreements.