Risks of toxic ash from artisanal mining of discarded cellphones

The potential environmental and human health impacts of artisanal mining of electronic waste through open incineration were investigated. A market-representative set of cellphones was dismantled into four component categories-batteries, circuit boards, plastics and screens. The components were shredded, sieved and incinerated at 743-818 degrees C. The concentrations of 17 metals were determined using U.S. EPA methods 6010C (inductively coupled plasma-atomic emission spectrometry; 6020A (inductively coupled plasma-mass spectrometry, or 7471B and 7470A (cold-vapor atomic absorption). EPA Method 8270 (gas chromatography/mass spectrometry) was used to identify polyaromatic hydrocarbon compounds and polybrominated diphenyl ethers. EPA Method 8082A was used to measure polychlorinated biphenyls and EPA Method 8290 was used for dioxin/furans in the residue ash. The life cycle assessment model USEtox (R) was used to estimate impacts of the ash residue chemicals on human health and the ecosystem. Among metals, copper in printed circuit boards had the highest ecotoxicity impact (1610-1930 PAF m(3)/kg); Beryllium in plastics had the highest impact on producing non-cancer diseases (0.14-0.44 cases/kg of ash); and Nickel had the largest impact on producing cancers (0.093-0.35 cases/kg of ash). Among organic chemicals, dioxins from incinerated batteries produced the largest ecotoxicological impact (1.07E - 04 to 3.64E - 04 PAF m(3)/kg). Furans in incinerated batteries can generate the largest number of cancers and non-cancer diseases, representing 8.12E - 09 to 2.28E - 08 and 8.96E - 10 and 2.52E - 09 cases/kg of ash, respectively. The results reveal hazards of burning discarded cellphones to recover precious metals, and pinpoints opportunities for manufacturers to reduce toxic materials used in specific electronic components marketed globally. (C) 2014 Elsevier B.V. All rights reserved.