RESUMEN

Informal electronic waste (e-waste) dismantling activities contribute to releasing hazardous compounds in the environment and potential exposure to humans and their health. These hazardous compounds include persistent organic pollutants (POPs), polycyclic aromatic hydrocarbons (PAHs) and heavy metals. This review searched papers addressing hazardous compounds emitted from e-waste recycling activities and their health effects in Vietnam. Based on the keywords searched in three electronic databases (PubMed, Psych Info, and Google scholar), we found 21 relevant studies in Vietnam. The review identifies extensive e-waste dismantling activities in Vietnam in the northern region. To measure the environmental exposure to hazardous compounds, samples such as e-waste recycling workshop dust, soil, air, and sediments were assessed, while human exposure levels were measured using participants' hair, serum, or breast milk samples. Studies that compared levels of exposure in e-waste recycling sites and reference sites indicated higher levels of PBDEs, PCBs, and heavy metals were observed in both environmental and human samples from participants in e-waste recycling sites. Among environmental samples, hazardous chemicals were the most detected in dust from e-waste recycling sites. Considering both environmental and human samples, the highest exposure difference observed with PBDE ranged from 2-48-fold higher in e-waste processing sites than in the reference sites. PCBs showed nearly 3-fold higher levels in e-waste processing sites than in reference sites. In the e-waste processing sites, age-specific higher PCB levels were observed in older recycler's serum samples. Among the heavy metals, Pb was highly detected in drinking water, indoor soil and human blood samples. While high detection of Ni in cooked rice, Mn in soil and diet, Zn in dust and As in urine were apparent. Exposure assessment from human biomonitoring showed participants, including children and mothers from the e-waste processing areas, had higher carcinogenic and non-carcinogenic risks than the reference sites. This review paper highlights the importance of further comprehensive studies on risk assessments of environmentally hazardous substances and their association with health outcomes at e-waste processing sites.

RESUMEN

The article draws attention to the problem of the presence of metals: germanium (Ge), tellurium (Te), thallium (Tl), and others (Cd, Ba, Co, Mn, Cr, Cu, Ni, Pb, Sr, and Zn) in selected waste of electrical and electronic equipment (WEEE). As a result of the growing demand for new technologies, the global consumption of TECs has also been increasing. Thus, the amount of metals in circulation, of which the impacts on the environment have not yet been fully understood, is constantly increasing. Due to the low content of these metals in WEEE, they are usually ignored during e-waste analyses. The main aim of this study was to determine the distribution of Ge, Te, and Tl (and other elements) in ground sieve fractions (1.0, 0.5, 0.2, and 0.1 mm) of selected electronic components (solar lamps, solar cell, LED TV screens, LCD screens, photoresistors, photodiodes, phototransistors) and to determine the possible tendency of the concentrations of these metals in fractions. This problem is particularly important because WEEE recycling processes (crushing, grinding, and even collection and transport operations) can lead to dispersion and migration of TCE pollutants into the environment. The quantitative composition of e-waste was identified and confirmed by ICP-MS, ICP-OES and SEM-EDS, and XRD analyses. It was found that Ge, Te, and Tl are concentrated in the finest fractions of ground e-waste, together with Cd and Cr, which may favor the migration of these pollutants in the form of dust during storage and processing of e-waste.

RESUMEN

Flame retardants (FRs) from electronic waste (e-waste) are a widespread environmental concern. In our study, in vitro physiologically based extraction tests (PBETs) for FRs were conducted in three different areas where dust remained after processing of e-waste to identify the bioaccessible FRs and quantify their bioaccessibilities of gastrointestinal tract for human as well as to assess the exposure via ingestion of workers in e-waste processing workshops. All 36 FRs were measured and detected in indoor dusts. Among the FRs, the mean concentrations of polybrominated diphenyl ethers (PBDEs) in the floor dust and settled dust were highest, 65,000 ng/g, and 31,000 ng/g, respectively. In contrast, phosphorus-containing flame retardants (PFRs) presented the highest mean concentration in the workplace dust samples, 64,000 ng/g. However, the highest bioaccessible concentrations in workplace dust, floor dust, and settled dust were observed for PFRs: 5900, 1600, and 680 ng/g, respectively. This study revealed that the higher bioaccessibility of PFRs versus other compounds was related to the negative correlation between FR concentrations and log KOW (hydrophobicity) values. The fact that hazard indices calculated using measured bioaccessibilities were less than 1 suggested that the non-cancer risk to human health by the FRs exposure via dust ingestion might be low.

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RESUMEN

Crude or primitive recycling practices are often adopted in material resource recovery from E-waste in developing nations. Significant human health and environmental impacts may occur because of such practices. Literature on metal(loid)s pollution during E-waste processing is fragmented. Here, I review the health and environmental impacts of E-waste recycling operations and transport pathways of metal(loid)s, dispersed during operations. This paper is organised into five sections. Section 1 relates to the background of global E-waste generation and legal/illegal trade, citing specific cases from Ghana and other developing nations. Section 2 provides a brief information on sources of metal(loid)s in E-waste. Section 3 describes characteristics of informal E-waste recycling operations in developing nations. Section 4 examines the health and environmental impacts in E-waste recycling while section 5 evaluates major transport pathways of metal(loid)s contaminants.

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