Children’s products sold in South Africa could be contaminated with traces of persistent organic pollutants (POPs) — toxic chemicals banned globally years ago — according to new research that raises concerns about toxic substances re-entering consumer products through recycled electronic waste.
A new study by researchers at the University of Cape Town (UCT) found bromine and antimony, which are chemical markers consistent with legacy brominated flame retardants, in a range of children’s products, suggesting they might have been contaminated through recycled electronic waste.
The products include Rubik’s Cubes, toy cellphones, puzzle mats, sunglasses, toy vehicles and child car seats.
Published in the journal Heliyon, the research provides preliminary evidence that recycled plastics from waste electrical and electronic equipment might be carrying banned chemicals back into everyday products intended for children.
Brominated flame retardants (BFRs), including polybrominated diphenyl ethers and hexabromocyclododecane, were widely used for decades in electrical and electronic equipment, furniture and vehicles to reduce fire risk.
Between 2009 and 2017, they were listed for global elimination under the Stockholm Convention after being linked to harmful environmental and health effects, including endocrine disruption, developmental neurotoxicity and cancer.
The study, led by Rebecca Mlelwa as part of her PhD research under the supervision of professor Andrea Rother in UCT’s environmental health division, sought to determine whether children’s products in South Africa showed evidence of contamination by the legacy chemicals.
The researchers screened 138 new and second-hand children’s products using a handheld X-ray fluorescence (XRF) spectrometer, which measures bromine and antimony as proxy indicators for brominated flame retardants.
The products were deliberately selected because they were made from plastic materials that previous international research has associated with recycled plastics containing the chemicals.
Bromine was detected in 38% of the products analysed, with concentrations ranging from 10mg/kg to 7 223mg/kg. Antimony was present in 90% of the bromine-positive samples.
The highest bromine concentrations were found in Rubik’s Cubes, a toy cellphone and a puzzle mat. Other products showing evidence consistent with contamination included sunglasses, child car seats, toy cars, motorcycle toys, toy baskets and trolleys, toy stethoscopes and toy pistols.
The researchers found that the ratio of bromine to antimony matched that typically seen in commercial brominated flame-retardant formulations.
However, the concentrations were far below those normally required for a flame-retardant function, leading the authors to conclude that the chemicals were unlikely to have been intentionally added during manufacturing.
Instead, they suggest the contamination probably occurred because plastics from discarded electronic equipment containing legacy flame retardants had been recycled into new consumer products.
“The low concentrations observed in this study and the persistence of POPs-BFRs during recycling provide evidence of the incorporation of recycled plastics into new products,” the authors write.
Using estimated concentrations of one flame retardant, decabromodiphenyl ether (DecaBDE), the researchers found that about 85% of products containing bromine exceeded the Basel Convention’s lowest provisional threshold used to identify waste contaminated with POPs that requires careful management.
The findings add to growing international evidence that hazardous chemicals banned years ago continue to circulate through global recycling systems.
Previous studies have reported similar contamination in children’s products sold in countries including Belgium, the UK, US, China, France and Australia. The authors say, however, that comparable research has been lacking in South Africa.
The paper highlights what the researchers describe as a “vicious cycle” in the global circular economy. South Africa exports much of its waste electrical and electronic plastics for processing overseas because of limited domestic recycling capacity. The recycled plastics can then be incorporated into new products that are imported back into the country.
Among the bromine-positive products examined, about 65% of those whose origin could be identified had been manufactured in China, although the authors note that South Africa imports more than 90% of its toys from China and that many products lacked labels identifying their country of origin.
Children are particularly vulnerable to exposure because their organs and nervous systems arel developing, their bodies are less able to detoxify hazardous chemicals and they frequently handle and mouth plastic toys.
Previous research has shown exposure can occur through direct contact with contaminated products, mouthing toys, skin contact and the ingestion of contaminated household dust.
The authors argue that South Africa’s regulatory framework contains important gaps. Although the country has ratified the Stockholm Convention and introduced regulations to phase out POPs, there are no specific legal limits for the chemicals in children’s products or waste electrical and electronic equipment and no comprehensive monitoring programme for legacy brominated flame retardants in consumer products.
The findings highlight a growing challenge for the global shift towards a circular economy. While recycling reduces waste and conserves resources, the researchers argue that stronger controls are needed to prevent hazardous legacy chemicals from old electronic equipment being recycled into new consumer products intended for children.
They recommend stronger regulatory oversight involving the National Consumer Commission and the departments of health and forestry, fisheries and the environment, including routine screening of children’s products before they reach the market.
The researchers also suggest portable XRF screening technology could be used for spot checks at ports of entry and retail outlets.
The authors caution that their findings should be interpreted as indicative rather than definitive. The handheld XRF instrument detects bromine and antimony as indicators of brominated flame retardants but cannot directly identify or quantify individual banned chemicals.
They recommend further laboratory analyses using more advanced techniques to confirm the presence and concentrations of specific compounds in children’s products sold in the country.
Protecting children from exposure to legacy pollutants requires multisectoral action, Mlelwa said in a statement. “Regulatory oversight and product screening will be critical to preventing hazardous substances from continuing to circulate in new products.
“Transparency and improved public awareness can help people make informed choices when buying these products.”