Cadmium

Primary reference(s)

WHO, 2019. Preventing disease through healthy environments – Exposure to cadmium: A major public health concern. World Health Organization (WHO). Accessed 19 July 2024.

Annotations

Key relevant UN convention / multilateral treaty

The UNECE Convention on Long-range Transboundary Air Pollution.

Drivers

Cadmium contained in soil and water can be taken up by certain crops and aquatic organisms and accumulate in the food chain. Food constitutes the main environmental source of cadmium for non-smokers (see CH0601 Levels of Contaminants in Food and Feed). Highest cadmium levels are found in the kidney and liver of mammals when fed with cadmium-contaminated feed, and in certain species of oyster, scallop, mussel and crustacean (WHO, 2019). 

The tobacco plant naturally accumulates relatively high concentrations of cadmium in its leaves. Thus, smoking tobacco is an important source of exposure and – in the case of heavy smokers – daily intake may exceed that from food. Cigarette smoking can cause significant increases in the concentration of cadmium in the kidney, the main target organ for cadmium toxicity (WHO, 2019). 

Inexpensive jewellery, toys and plastics can be significant sources of exposure to cadmium, especially for children; however, many countries have moved to restrict or ban cadmium in such products (WHO, 2019). 

In terms of occupational exposure through industrial processes, principal uses are currently in nickel-cadmium batteries, pigments, coatings and plating, as a stabiliser in plastics and other materials (including non-ferrous alloys, semiconductors and photovoltaic devices). The highest potential occupational exposures occur in cadmium production and refining, nickel-cadmium battery manufacture, cadmium pigment manufacture and formulation, cadmium alloy production, mechanical plating, zinc smelting, brazing with silver-cadmium-silver alloy solder and polyvinylchloride compounding (WHO, 2019). 

Impacts

Impacts of cadmium exposure include environmental impacts (soil contamination, particularly near industrial sites; water pollution from leaching; and biodiversity loss); human health impacts (kidney damage from ingestion through food and water; bone damage; respiratory issues; and carcinogenic effects); and economic impacts (agricultural losses from reduced crop yields and quality; and healthcare costs for the human health impacts). Documented accidents involving cadmium have occurred in various industries and settings, leading to significant health and environmental impacts. 

One of the most well-known incidents involving cadmium occurred in the Jinzu River basin in Toyama Prefecture, Japan, during the mid-20th century. Widespread mining and industrial activities released cadmium into the river, contaminating rice paddies and water supplies. As a result, residents, particularly women, who consumed cadmium-contaminated rice and water developed severe renal and skeletal abnormalities, known as Itai-Itai Disease.  

In the 1910s and 1920s, industrial activities in Toyama Prefecture, Japan, led to the release of cadmium and other heavy metals into the environment, contaminating soil, water, and crops. This pollution resulted in widespread health problems among residents, including kidney damage and skeletal deformities. 

In 2003, in Bangalore, India, the Janaagraha organization discovered lead and cadmium contamination in groundwater sources used by local residents. The contamination was traced to a battery recycling plant in the vicinity. Residents, particularly children, were found to have elevated levels of lead and cadmium in their blood, leading to health concerns and protests against the plant's operations.  

Accidental releases of cadmium from industrial facilities, such as metal plating plants, battery manufacturing facilities, and electronic waste recycling operations, have led to localized contamination of air, soil, and water. These incidents can result in acute exposure to cadmium, causing respiratory problems, gastrointestinal issues, and other health effects among workers and nearby residents. (ATSDR, 2012)  

These documented accidents underscore the importance of monitoring and regulating cadmium exposure, implementing pollution control measures, and promoting safe handling and disposal practices to prevent adverse health and environmental impacts. 

Multi-hazard context

The figure below summarises common interactions between cadmium and other hazards. This information should be used with caution and not be solely relied upon in Disaster Risk Management, particularly as some interactions may not have been included. Note that hazardous events occurring together or locally in space or time may not necessarily cause, amplify or be otherwise related to each other. Specific examples of multi-hazard context can be found in the ‘Hazard drivers’ and ‘Impacts’ sections above.

Multi-hazard diagram

Risk Management

The WHO factsheet on preventing disease through healthy environments (WHO, 2019) includes the following risk mitigation recommendations: 

• Implement the WHO Framework Convention on Tobacco Control, including providing for protection from exposure to tobacco smoke in indoor workplaces, public transport, indoor public places and, as appropriate, other public places (WHO, 2003).
• Reduce, as far as is practicable, emissions of cadmium – particularly into surface waters – from mining and smelting, waste incineration, application of sewage sludge to the land, and use of phosphate fertilisers and cadmium-containing manure. Develop techniques for the safe disposal of cadmium-containing wastes and effluents.
• Washing fruit and vegetables and peeling roots and tubers can help reduce cadmium contamination.
• Promote safe and effective measures to increase recycling of cadmium and to restrict non-recyclable uses.
• Promote the elimination of use of cadmium in products such as toys, jewellery and plastics.
• Reduce cadmium exposure by, for instance, improving working conditions in the non-ferrous metal smelting industry and disseminating information on the proper selection of fertilisers (which sometimes contain high levels of cadmium).
• Raise global awareness on the importance of minimising waste discharges of cadmium.

Monitoring

The section and the table below offer an overview of monitoring cadmium. This information can be used for forecasting within a national early warning system (EWS). Since EWS capacities and processes differ across countries, the most current and specific information regarding EWS should be obtained from the appropriate national or regional agency/authority responsible for disaster management.