Emerging Synthetic Antioxidants are Emitted by E-waste Recycling

Every year, millions of electronic items such as televisions, laptops, and mobile phones are abandoned in Australia. In reality, e-waste is the most rapidly expanding component of municipal solid garbage. According to the Global E-Waste Monitor 2020, e-waste (discarded products with a battery or plug, such as computers and mobile phones) increased by 21% in the five years to 2019 and is expected to nearly double by 2030, driven by higher consumption rates, shorter lifecycles, and limited repair options.

To make plastics, rubbers, and other polymers endure longer, manufacturers add synthetic antioxidants. However, the health impacts of these substances, as well as how easily they migrate into the environment, are largely unclear. Researchers have discovered a wide spectrum of new synthetic antioxidants, known as inhibited phenol and sulfur antioxidants, in dust from electronic waste (e-waste) recycling factories, potentially posing dangers to the workers within.

Previous research found widespread contamination and human exposure to a family of chemicals known as low-molecular-weight synthetic phenolic antioxidants. Some of these chemicals proved hazardous to rats or human cells in laboratory tests. Manufacturers have created a new class of high-molecular-weight synthetic phenolic antioxidants, commonly known as hampered phenol antioxidants (HPAs), that have increased performance and migrate slower from products. In addition to HPAs, sulfur antioxidants (SAs) are frequently added as “helper” antioxidants to rubber and plastic polymers.

The researchers gathered 45 dust samples from three types of e-waste recycling businesses in an industrial park in Yichun City, China, in August 2020: wire and cable disassembly, electronic plastic processing, and general e-waste dismantling. Most of these novel chemicals’ toxicological effects and environmental prevalence remain unknown.

Lixi Zeng

Most of these novel chemicals’ toxicological effects and environmental prevalence remain unknown. As a result, Lixi Zeng and colleagues decided to look into the presence of growing HPAs and SAs in dust from e-waste recycling centers, which are workshops where vast volumes of abandoned electronics such as laptop computers, cell phones, tablets, wires, and cables are dismantled and processed.

The researchers gathered 45 dust samples from three types of e-waste recycling businesses in an industrial park in Yichun City, China, in August 2020: wire and cable disassembly, electronic plastic processing, and general e-waste dismantling. They then employed liquid chromatography/tandem mass spectrometry to look for 18 new HPAs and 6 new SAs. All 24 chemicals were found in the dust, 22 of them for the first time, and some at relatively high quantities when compared to other e-waste contaminants.

E-waste recycling emits emerging synthetic antioxidants

Although dust concentrations of SAs were similar across all workshop types, centers that removed wires and cables and processed electronic plastics had much higher levels of dust HPAs than centers that dismantled general e-wastes. Given the prevalence of developing HPAs and SAs in e-waste dust, the researchers believe that more research on their environmental behaviors, fates, toxicities, and hazards is required.

Improper e-waste disposal in landfills or other non-dumping areas poses major dangers to present public health and has the potential to harm ecosystems for future generations. Toxic chemicals are generated when electronics are incorrectly disposed of and wind up in landfills, affecting the earth’s air, soil, water, and, ultimately, human health.

When e-waste is informally disposed of by dismantling, shredding, or melting the components, dust particles or poisons, such as dioxins, are released into the environment, causing air pollution and harming respiratory health. E-waste of little value is frequently burned, however burning also acts as a method of extracting valuable metals from electronics, such as copper. Chronic diseases and cancers are more likely to arise when e-waste is burned because it emits small particles that can travel thousands of kilometers, posing severe health dangers to humans and animals.

Toxic components in electronic trash include mercury, lead, cadmium, polybrominated flame retardants, barium, and lithium, all of which are hazardous to human health. Toxins’ harmful health impacts on humans include damage to the brain, heart, liver, kidneys, and skeletal system. It can also have a significant impact on the neurological and reproductive systems of the human body, resulting in sickness and birth abnormalities. Improper e-waste disposal is extremely hazardous to the global ecosystem, which is why it is critical to raise awareness about this rising problem and its potentially disastrous consequences. To reduce the hazardous impacts of e-waste, it is critical to e-cycle goods effectively so that they can be recycled, refurbished, resold, or repurposed. The growing stream of e-waste will only worsen if not educated on the correct measures of disposal.