ENVIRONMENTAL HEALTH GUIDE LEAD SOURCES IN THE HOME - WHAT TO AVOID

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1 ENVIRONMENTAL HEALTH GUIDE LEAD SOURCES IN THE HOME - WHAT TO AVOID WHAT IS LEAD? Lead is a naturally occurring metal found within the earth s crust and is a soft greyish-blue colour. SOURCES OF LEAD Lead is found in: rechargeable batteries solder weights or sinkers bullets and pellets printing materials (printer s ink, typesetting materials) glazes (especially pottery) and glass petrol pigments, including some cosmetics paints (particularly industrial paints) certain herbal preparations In addition, contamination of air, food and water can arise from: lead mining and production activities lead smelting activities (none exist in WA) industries that use lead or lead-containing materials sites contaminated by previous industrial activities motor vehicle emissions home maintenance or hobbies using lead materials IS IT POISONOUS? When absorbed into the body, lead is retained for a long time. On repeated exposure to low levels, lead will accumulate in the body and may cause pain and illness. Lead interferes with the production of haemoglobin in the blood which may cause tiredness and shortness of breath on exertion. Lead may also affect the kidneys and liver. Children are likely to absorb up to five times more ingested lead than adults with relatively low levels of lead having the potential to affect a child s intellectual development and behaviour. As children are smaller and still developing, this higher absorption rate is of particular concern. However, severe lead poisoning is now rare in Australia. Lead can easily cross the placenta and accumulate in, and may affect, the developing foetus. It is particularly important that pregnant women and children under five years of age avoid exposure to lead from any source as they are most sensitive to lead contamination. People with iron and calcium deficiency tend to ingest more lead. A single exposure to a high concentration of lead, e.g. eating flakes of leaded paint, can cause significant elevated blood lead levels for several weeks.

2 SYMPTOMS OF LEAD EXPOSURE Symptoms of lead exposure can be difficult to recognise. The family doctor should be consulted if lead exposure is suspected. The Significance of Various Blood Lead Levels (μg/dl*) Blood Lead Levels Health Effects Children Adults more than70 more than 80 Severe toxicity (coma, convulsions, death) less than 45 Less than 60 Usually no symptoms - 60 (30 for females of reproductive capacity) Maximum level permitted for occupational exposure NHMRC goal less than 6 less than 6 90% of blood lead results in 1995 national survey NHMRC Recommended Response for Children s Blood Levels Blood Lead (μg/dl*) Response more than 55 Urgent specialist paediatric assessment and advice regarding chelation more than 25 Medical examination including nutritional & developmental status more than 15 Exposure evaluation and remediation * micrograms/decilitre or micrograms/100ml. EXPOSURE TO LEAD Lead can enter the body through the mouth, lungs or skin. Exposure may occur at home or at work. For information on exposure at work, contact WorkSafe Western Australia, telephone (08) INGESTION (EATING) OF LEAD Children under five years old are more at risk of ingesting lead than others because of their tendency to place any object in their mouths, suck their fingers and generally swallow dust and soil. Food The Australian Market Basket Surveys indicate that the amount of lead in food is decreasing. Water Water from reticulated water supplies is unlikely to be a major source of lead, except in very old houses with lead plumbing. Domestic lead water pipes have not been installed in Western Australia for at least 40 years. Water from some hot water urns has been found to contain lead. However, unless coffee, tea and other hot drinks are the major source of water, the amounts of lead ingested from this source are unlikely to be excessive, particularly for children under five. Crystal glassware Some forms of crystal contain lead and are usually labelled as such. New lead crystalware contains a layer of lead particles loosely bound to the glass surface. Acidic liquids and alcoholic beverages stored in new lead crystalware can contain high levels of lead.

3 Glazed Pottery Some glazes contain lead which can leach into food stored in pottery containers for any appreciable time. Paint State legislation prohibits the use of paints containing more than 0.1% lead on any toys, furniture, fences and on interior or exterior surfaces of non-industrial premises. During renovations of older houses, layers of paint containing lead can often become exposed. People (mainly children) who have swallowed flakes of lead paint have suffered lead poisoning. Paints manufactured for industrial use, including motor vehicle and marine paints, may contain more than 0.1% lead, but must carry strict warning labels on the containers. However, lead-contaminated fumes and dust may be generated when working with fresh paints or restoring painted surfaces. Contaminated Clothing Lead-contaminated clothing from work or hobbies is a major source of exposure to people who handle or come into contact with it (e.g. laundry operators). It is also a major source of lead contamination in some homes. Children in particular can be at risk if allowed to play amongst the contaminated clothing. Contaminated Soil Soil around the house may be contaminated from lead waste generated by current or past activities carried out on the premises or in the neighbourhood. These activities include battery recycling, radiator maintenance, soldering, removing paint, spray painting cars and boats, and various hobbies that use lead or materials that contain lead. Children under five years old are particularly at risk of ingesting lead from this source. INHALATION OF LEAD IN AIR Lead in the air contributes, in some cases appreciably, to contamination of soil, water and food. Levels of lead in Perth s air have been consistently below the National Health and Medical Research Council (NHMRC) guidelines since However, lead air concentrations in and around the house may occasionally be higher while doing some of the activities described below. A number of do-it-yourself activities and hobbies can produce dangerous levels of lead fumes and dust which can be inhaled or contaminate the house and garden. Such activities include car engine maintenance, making lead sinkers, panel beating or other body work on cars and boats, sanding or stripping old paint, spray painting cars and boats, and heating, burning, flame cutting, melting, grinding or sanding any other products which contain lead. Up to 90% of lead in air comes from the exhaust fumes of cars using leaded petrol. A large proportion of cars in Australia still run on leaded fuel. Intentional or unintentional inhalation of leaded petrol fumes can also be a major source of lead intake. Burning old wood painted with lead-based paints will release lead into the air Some industries such as lead mining, smelting and those that use lead or products containing lead contribute to airborne lead if adequate pollution control measures are not in place. In Western Australia, there is only one small lead mine but many industries where lead or products containing lead are used.

4 SKIN ABSORPTION Absorption of lead through the skin from contaminated materials (clothing, soil etc.) is minimal. However, certain solvents in petrol may increase the absorption of lead through the skin. ARE WE OVEREXPOSED TO LEAD? Most adults who do not work with lead are not overexposed to lead. Adult intake of lead from food, water and air sources is estimated to be below the NHMRC (1990) Provisional Tolerable Weekly Intake for lead. However, some children may be overexposed. The most recent recommendation of the NHMRC is that lead exposure should be minimised as far as possible to reduce blood lead levels particularly in children. The NHMRC in 1993 set a specific goal for all Australians to have a blood lead level of below ten micrograms per decilitre (10 μg/l or 0.48 micromoles per litre), with a particular urgency in reaching this level in children aged one to four years. In a national survey completed in 1995 more than 90% of Australian children had blood lead levels less than 6 μg/dl, well below the target. WHAT SHOULD YOU DO? Pregnant women and young children should keep well away from areas which may be contaminated with lead and avoid activities which generate fumes or dust that is contaminated with lead. Avoid contaminating your house and garden when working at home with lead or products which could contain lead. Use an area which can be isolated and readily cleaned. When heating, welding, flame cutting or burning products which could contain lead, work in a well ventilated area and wear a respirator fitted with suitable lead filters. Filters are available which protect from dust or fumes; choose the one appropriate for the task. Keep children well away from these activities. Thoroughly clean areas contaminated with paint flakes and/or dust when renovating flaking paint surfaces on older properties. Use an industrial vacuum cleaner fitted with high efficiency filters, or a wet rag or mop. Use chemical paint strippers instead of blow torches or sandpaper when removing old paint which might contain lead. Chemical paint strippers can themselves be very toxic, so read the label and follow all safety directions. Do not burn painted wood. Wash hands before eating, drinking, smoking or touching children when working with lead or materials containing lead. If working at home with lead or materials which may contain lead, thoroughly wash any home-grown vegetables or fruit before eating. Do not take contaminated work clothes home. If you have to, remove as much dust as possible from them and keep them in a plastic bag until they are washed. Avoid touching or playing with children when wearing contaminated clothing. Buy foods in welded rather than soldered cans, as lead can be present in the solder. New lead crystal glassware or glazed pottery, to be used for storing food or drink, should be cleaned by soaking in vinegar for at least 24 hours to remove lead which could leach into beverages or food.

5 Avoid using petrol as a solvent. Wear non-absorbent gloves when handling petrol or servicing motor vehicles. Do not dispose of your waste petrol or oils in the backyard. Check whether your car will run on unleaded petrol. Contact your garage or local automobile club to find out. Children who are at risk of exposure to lead should have their blood tested for lead levels. The family doctor can do this. DISPOSAL OF ITEMS WHICH CONTAIN OR ARE CONTAMINATED WITH LEAD Items which contain lead or are contaminated with lead should not be discarded with general household refuse or be buried in the backyard. Some products which contain lead such as old car batteries, radiators, lead flashing, can be recycled. Further information regarding recycling and safe disposal options is available from your local government waste management department. Further information contact Toxicology Branch of the Environmental Health Directorate on Telephone: (08)