Control measures


At every stage in the recycling process there are measures that can be taken to prevent or reduce the release of lead. A detailed description of control measures is beyond the scope of this document but brief information is given here. Further information can be found in technical guidelines and a training manual published by the Basel Convention Secretariat and in technical guidelines published by the Commission for Environmental Cooperation (CEC). These provide practical advice and guidance to national authorities on the environmentally sound management of used lead-acid batteries (UNEP, 2003; UNEP, 2004; CEC, 2016). The US Occupational Safety and Health Administration provides information about engineering and other controls in its e-learning tool on secondary lead smelting (OSHA, 2002).

Battery collection, storage and transportation 

Measures that should be taken at battery collection and storage sites include the following (CEC, 2016; UNEP, 2003). Batteries should not be drained at the collection point. They should be stored securely and sheltered from the weather. The storage location should be well ventilated and the ground should be coated with acid-resistant concrete or other resistant material. Leaking batteries should be placed in acid-resistant containers. The number of stored batteries should be controlled. There should be prominent hazard warnings. Battery collectors should not sell their batteries on to unlicensed lead smelters. Used lead-acid batteries should be transported as hazardous waste. The batteries should be kept upright and separated by cardboard or other non-conducting material and then placed in sealed containers or otherwise secured, e.g. on pallets covered with shrink wrap, to prevent them moving about.

Battery recycling 

To minimize lead exposure and environmental contamination, lead battery recycling should only be conducted at adequately equipped and regulated facilities that have the requisite engineering controls, trained staff, provision of protective equipment, and environmental and occupational monitoring.

The most important and effective control measures are engineering and emission controls. However, work practice controls are also needed to protect the health of workers and reduce emissions to the outside (OSHA, 2002). Engineering controls include the use of fully automated and enclosed operations for the dismantling and separation of lead-acid batteries and the smelting and refining of lead. Fugitive emissions from the various stages of the recycling process can be reduced by the use of negative pressure enclosures, i.e. a sealed area where adequate ventilation is in place to create a negative pressure that is exhausted through an emission control device and/or a high‐efficiency particulate air (HEPA) filter to trap particles and dust. The use of hooding and exhaust ventilation over open areas of operation, e.g. battery saws and crushers, furnace feed conveyors and furnace charging points, will trap dusts and fumes. Keeping molten lead at lower temperatures will reduce the amount of fume. Dust and particle emissions should be trapped in a filter baghouse, by using a wet electrostatic precipitator or by other similar technologies (CEC, 2016). These traps should be regularly cleaned and the contents fed into the smelter to recover the lead. There should be an effluent treatment station to treat all water used in the recycling process and for cleaning (CEC, 2016). Rainwater run-off from roofs and other surfaces, which are likely to be contaminated with lead, should also be collected and treated (UNEP, 2003). Other techniques to reduce dispersion of dust include keeping all open operations wet, ensuring that batteries and slag are safely stored under cover and kept away from water, and ensuring that the whole operating area is kept clean using wet methods and HEPA vacuuming. There should be regular environmental monitoring to ensure that control measures are effective. In addition to providing adequate ventilation, workers’ exposure can further be reduced by the following measures (OSHA, 2002; UNEP, 2003; Kosnett et al., 2007; CEC, 2016): • training on the hazards of lead and measures to prevent exposure; • providing, and enforcing the use of, personal protective equipment (see below); • prohibition of smoking, eating or drinking in the workplace; • providing a segregated eating area well away from recycling operations; • providing a clean air room, maintained at positive pressure and with filtered air, for the removal of respirators; • providing, and enforcing the use of, facilities for workers to change into clean work clothing before starting work and to wash and change clothes at the end of the working day; • the implementation of a policy for regular blood lead testing, with a specified medical removal level to remove an over-exposed worker from working around lead, together with provisions for alternative employment or compensation.

Medical removal levels vary from country to country and are usually lower for women than for men. There is also a voluntary industry initiative among battery companies in a number of countries to maintain workers’ blood lead concentrations below 30 μg/dL (EUROBAT, 2013). Ensuring that workers wash and change before leaving the facility is important for protecting household members from take-home exposure to lead.

Personal Protective Equipment (PPE)

The required personal protective equipment will vary according to the specific tasks being carried out and the concomitant risk of exposure to lead and other hazards. Equipment may include: full-body coveralls, apron, gloves, hard hats, shoes or disposable shoe covers, respirators, face shields or vented goggles (OSHA, 2002; CEC, 2016). It is important that this equipment is regularly cleaned and maintained in good repair. It should be noted that respiratory protection is not a substitute for adequate ventilation and pollution controls in the workplace but can be used along with these other measures.

Informal recycling

It is clear from the above description of control measures that it is not possible for informal recycling to be carried out in an occupationally and environmentally sound way. Preventing informal recycling presents a number of challenges and it is important to take a holistic approach. Recycling is often carried out in a covert way, e.g. at night or in constantly changing locations. Therefore, identifying operations in order to close them down may be difficult. In addition, for people with limited employment opportunities, recycling may provide a critical source of family income with consequent repercussions if it is stopped and no alternative is provided. The Basel Convention Secretariat devotes a chapter of its training manual to the problem of controlling informal recycling and suggests a number of approaches (UNEP, 2004). These include determining the likely scale of operations through a market analysis of battery imports and sales, and identifying the points of interaction between the informal and formal sectors, as well as collecting information about recycling practices to determine where interventions can be targeted. The life-cycle of a lead-acid battery involves manufacturers, retailers, scrap dealers, secondary smelters and consumers. Each can play a part in preventing the supply of used lead-acid batteries to the informal recycling sector. Some suggested approaches include: • encouraging the collection of used batteries by licensed retailers when replacement batteries are being bought, for example by requiring a returnable

deposit or refund scheme that would price lead batteries at a level closer to the actual intrinsic value of the lead and more than the informal sector would be willing to pay; • requiring manufacturers to take back used lead-acid batteries in order to sell them to licensed recyclers (extended producer responsibility); • informing consumers about the value of recycling lead-acid batteries and the dangers of dumping or supplying batteries to unlicensed smelters; • informing the public at large about the health and environmental hazards of lead; • encouraging the technological development of lead-acid batteries to make them last longer; • prohibiting the sale of used lead-acid batteries to unlicensed smelters; • creating a role for the informal sector e.g. by developing the necessary infrastructure that encourages scavengers to take batteries to licensed smelters; and • sharing experiences between countries on approaches to controlling informal recycling (UNEP, 2004).

The problem of lead acid pollution

Lead is persistent and highly immobile in the environment and surface lead concentrations are unlikely to migrate to subsurface soils even after a prolonged period (Kabala & Singh, 2001). Sites where recycling activity has taken place will, therefore, continue to pose an exposure risk to local populations. Consideration should therefore be given to methods of mitigating exposure, for example through environmental remediation.

Policy measures

Enforcement of the control measures described above requires a national policy to be put in place for the sound management of used lead-acid batteries that encompasses standards for collection, recycling, emissions, and occupational safety (UNEP, 2003; UNEP, 2004). Relevant regulatory measures include landuse planning laws concerning the location of secondary smelters (e.g. distance from residential areas), environmental standards governing emissions and discharges, and occupational standards for workplace and worker monitoring (UNEP, 2004; van der Kuijp et al., 2013). For these measures to be successful there is also a need for adequate technical capacities, such as trained inspectors and laboratory facilities for the measurement of lead in biological and environmental samples, as well as appropriate enforcement measures. It is also important that the health sector, particularly at primary care level, is able to recognise possible lead poisoning and to initiate the necessary diagnostic and treatment interventions.

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