Solvents are often a health hazard. There are three ways that solvents can enter the body:

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1 Page 1 of 35 A solvent is a substance used to dilute or dissolve another substance to create a solution. This solution can then be used as a medium to carry a desired component e.g. a pigment and allow it to be applied onto a surface as a coating e.g. an ink or paint. are also used to clean materials from surfaces to prepare them for further use or application. Water is the most common solvent, as many substances are easily soluble in water. But some substances are not water soluble, and require other chemicals as solvents. Many solvents used in industry are "organic", petroleum-based chemicals which have powerful properties to dissolve solids. They are often mixtures of several substances and can be extremely hazardous. Historically, the use of solvents is widespread across industry as a fuel, a carrier for other materials (e.g. inks, paints) or as a cleaning agent. There are many examples but just a few of the most common are: MEK methyl ethyl ketone White Spirit a mix of hydrocarbons Toluene, xylene, hexane Petrol, diesel fuel Methanol & ethanol, Isopropanol Methylene chloride (used in paint stripper) are often a health hazard. There are three ways that solvents can enter the body: Inhalation Most solvents are "volatile", that is, they evaporate into the air very quickly. The vapours that result can then be breathed in and can easily pass through the lungs into the blood stream. Ingestion Solvent droplets can form in the hairs and airways inside the nose, be sniffed in or swallowed. Mouth contact with contaminated hands, food & cigarettes can also result in ingestion. Skin Absorption can be absorbed through the skin by contact and enter the bloodstream directly.

2 Page 2 of 5 CHNICAL UPDATE Health Effects Different solvents have different health effects, depending on how the exposure happens, how much there is and for how long. There has been increasing attention on the damage to the nervous system from solvent exposures. This is called neurotoxicity. It may be short-term (usually high level exposure and rapidly reversible once exposure has ceased) or long-term. Chronic (or long-term) effects are caused by degeneration of parts of the nervous system because of repeated low-level exposures. Short-term exposure can cause: Dermatitis or skin problems (drying, cracking, reddening or blistering of the affected area) Headaches, drowsiness, dizziness Poor coordination, unsteady gait Nausea (feeling sick), euphoria These effects can take place very quickly. In cases of exposure to very high concentrations of solvent vapour, unconsciousness and even death can occur. Repeated (long term) exposure to solvents may effect: The brain and the nervous system, including personality changes Irritability Sleep patterns The skin - causing dermatitis The liver - causing liver damage The blood-forming system (benzene is a proven blood cancer causing agent) The kidneys The fertility of both men and women The foetus in a pregnant woman Short term memory loss, reduced attention span Some solvents will have synergistic effects with other hazards and drugs. This means that the solvent will have greater health effects when exposure occurs in combination with another hazard. For example, the effects from the exposure to an organic solvent will be greater if you smoke cigarettes or drink alcohol soon afterwards. Excessive noise exposure can also have a greater effect on the auditory system when it occurs in conjunction with exposure to organic solvents. These synergistic effects have not been comprehensively identified or quantified for all potential combinations and there is still much to learn in this area.

3 Page 3 of 5 Sensitisation Another solvent related health effect is respiratory sensitisation. This is caused by exposure to specific substances, such as isocyanates, epoxy systems and rosin, which when inhaled can induce changes in the body's immune system. Sensitisation may occur as a result of repeated low-level exposure to particular substances, or to occasional short-term exposure to high concentrations, e.g. during maintenance or when materials are heated, sprayed or spilled. Recent scientific research also suggests that respiratory sensitisation to some sensitisers may be triggered by skin contact. Although the evidence is inconclusive, users should avoid skin contact with sensitisers where possible. TECHNICAL UPDATE This may mean that the next time a person is exposed to the sensitising substance, their body reacts dramatically, even if they have only been exposed to a very small amount of the substance, the person is said to have become sensitised. The result is that sufferers from this potentially life-threatening asthmatic type response may be unable to continue their job and some have become permanently incapacitated. Respiratory sensitisers are widely used in the spray painting and printing industries. Isocyanates are a widely used sensitising solvent found in adhesives, lacquers, primers and some printing inks or more commonly in 2-pack or epoxy paints used for spraying cars and other metal goods. It is not possible to predict who may become sensitised. A number of people may work with respiratory sensitisers under exactly the same conditions and some may become sensitised, while others may suffer no adverse health effects at all. Sensitisation can occur within a few weeks of being exposed to the substance but may not develop until after many years of symptom-free exposure. Sensitisation is all or nothing. You are either sensitised to a substance or you are not. It is also irreversible - you remain sensitised for life. People become sensitised to a particular substance. Symptoms usually only occur in response to that substance, although some people can have persistent asthma after exposure ceases. However, a person who has become sensitised to one substance may then be more likely to suffer adverse reactions to others in the same chemical class.

4 Page 4 of 5 Other Effects Large amounts of solvents are used simply for cleaning. Estimates are that offset printers in the European Union alone use around 100 million litres of organic solvents per year to clean their presses and between 60 and 90% of these petroleumbased solvents evaporate into the atmosphere. These volatile organic compounds (VOC s) in the atmosphere contribute to the thinning of the ozone layer and create smog at ground level; they can also be damaging in soil or water. So solvents are an environmental pollutant as well as a health hazard in industry. can be flammable or explosive, and exposing them to flame or hot surfaces can also form highly toxic decomposition products. Ignition sources such as welding torches, lit cigarettes and sparks should be kept away from solvent use and storage areas. In addition, some chemicals are incompatible with solvents and mixing will produce toxic gases, heat or fire. Oxidizers (e.g., sodium chlorate) and strong acids and bases (e.g. sulfuric acid, sodium hydroxide) should never come in contact with solvents. Clearly, there is a need for full awareness of the hazards and health issues associated with the use of solvents. All employers should perform a risk assessment of all chemicals used in their workplace. The basic information required for materials used can be found in the Material Safety Data Sheet (MSDS), which gives the relevant details on the ingredients, the health hazards and the controls required for safe use of the product. The MSDS can be sourced from the manufacturer or supplier of the material. Any personal protective equipment used must be of a type suitable for the particular chemicals in the solvent. Use of equipment that meets the requirements of the relevant Australian/New Zealand Standard will provide suitable protection in most cases. Persons spraying Isocyanates in 2-pack epoxy paints will need to use an air supplied respirator to minimise exposure levels. Monitoring and Exposure Control To determine whether the airborne concentrations of solvent vapours are significant, monitoring of the workforce is recommended. The solvent levels can be determined and appropriate measures identified. When using respiratory protection, the level of airborne solvent levels will be needed to assist in the determination of the types of respirators that will provide the protection levels needed to reduce these to an acceptable level.

5 Page 5 of 5 There are different ways and means to measure solvent levels, with advice and guidance from an occupational hygienist being valuable. This will ensure that workplace conditions, work patterns and appropriate sampling methods are used for the solvents involved. This information is valuable in providing scientifically based data to employees, unions, workplace inspectors etc. Control measures to prevent solvent exposures at work: Provide information and increase awareness of people who work with solvents. Store solvents in a cool place, away from any potential ignition sources. Ensure the storage area is well ventilated and firmly secured. Ensure solvent containers are labelled appropriately and follow the written advice. Contain spills or leak residues with appropriate absorbents. Do not allow spillages to enter drains or other waterways. Many solvents are flammable and suitable precautions need to be taken Reduce the amount you breathe in by: Avoiding the use of products with solvents in them. Making sure there is good ventilation in the work area where solvents are used. Using the minimum amount needed for the job and keeping lids closed. Wearing suitable respiratory protection - refer to Australian Standard AS/NZS1715. Take specific precautions if using solvents in confined spaces. Practice good hygiene by washing hands well before eating, drinking, smoking, etc. are a necessary and widely used class of chemicals throughout our modern industrialised society. However, they have associated health and safety hazards which need to be fully assessed and correct procedures created to ensure the health and safety of workers and others using these materials. Occupational Health and Environmental Safety Division 3M Australia Pty Limited Building A, 1 Rivett Road North Ryde NSW 2113 Phone: TechAssist Helpline: techassist@mmm.com Website: Occupational Health and Environmental Safety Division 3M New Zealand Ltd PO Box Takapuna, North Shore City 0740 Tech Helpline: innovation@nz.mmm.com Website: